[Application of bone flap pedicled on retrograde branch of radial artery for treatment of old scaphoid bone fractures of type AO-B].

PubMed

Sun, Qing-peng

2015-05-01

To investigate application of the bone flap pedicled on the retrograde branch of radial artery for treatment of old scaphoid bone fractures of type AO-B. From October 2007 to October 2011,41 patients with old scaphoid bone fractures of type AO-B were treated by transplantation of the bone flap pedicled on the retrograde branch of radial artery including 26 males and 15 females with an average of (27.3±4.5) years old ranging from 16 to 43 years old. The courses before operation ranged from 6 to 22 months with an average of 11 months. All fractures belonged to the type B of AO classification, that is old wrist fracture of scaphoid bone. All patients' wrist function (pain, function, motion, grip strength) were evaluated by Cooney's modifiedwrist scoring system before and 6 months after operation,and the conditions of bone healing were observed during the follow-up time. Among them, 36 patients were followed up from 4 to 15 months with an average of 8.3 months. The wounds were healed well without other complications as infection appearing. X-rays or CT confirmed that all fractures were healed completely. The Cooney wrist score was improved from preoperative 53.61±13.97 to postoperative 81.81±8.71 (P<0.01). The operation of transplantation of the bone flap pedicled on the retrograde branch of radial artery is an effective method to treat old scaphoid bone fractures,which is scientific and has curative effects, and valuable for clinical application.

Arterial endothelial function measurement method and apparatus

DOEpatents

Maltz, Jonathan S; Budinger, Thomas F

2014-03-04

A "relaxoscope" (100) detects the degree of arterial endothelial function. Impairment of arterial endothelial function is an early event in atherosclerosis and correlates with the major risk factors for cardiovascular disease. An artery (115), such as the brachial artery (BA) is measured for diameter before and after several minutes of either vasoconstriction or vasorelaxation. The change in arterial diameter is a measure of flow-mediated vasomodification (FMVM). The relaxoscope induces an artificial pulse (128) at a superficial radial artery (115) via a linear actuator (120). An ultrasonic Doppler stethoscope (130) detects this pulse 10-20 cm proximal to the point of pulse induction (125). The delay between pulse application and detection provides the pulse transit time (PTT). By measuring PTT before (160) and after arterial diameter change (170), FMVM may be measured based on the changes in PTT caused by changes in vessel caliber, smooth muscle tone and wall thickness.

Measurement of radial artery contrast intensity to assess cardiac microbubble behavior.

PubMed

Sosnovik, David E; Januzzi, James L; Church, Charles C; Mertsch, Judith A; Sears, Andrea L; Fetterman, Robert C; Walovitch, Richard C; Picard, Michael H

2003-12-01

We sought to determine whether analysis of the contrast signal from the radial artery is better able to reflect changes in left ventricular (LV) microbubble dynamics than the signal from the LV itself. Assessment of microbubble behavior from images of the LV may be affected by attenuation from overlying microbubbles and nonuniform background signal intensities. The signal intensity from contrast in a peripheral artery is not affected by these artifacts and may, thus, be more accurate. After injection of a contrast bolus into a peripheral vein, signal intensity was followed simultaneously in the LV and radial artery. The measurements were repeated using continuous, triggered, low and high mechanical index harmonic imaging of the LV. Peak and integrated signal intensities ranged from 25 dB and 1550 dB/s, respectively, with radial artery imaging to 5.6 dB and 471 dB/s with ventricular imaging. Although differences in microbubble behavior during the different imaging protocols could be determined from both the LV and radial artery curves, analysis of the radial artery curves yielded more consistent and robust differences. The signal from microbubbles in the radial artery is not affected by shadowing and is, thus, a more accurate reflection of microbubble behavior in the LV than the signal from the LV itself. This may have important implications for the measurement of myocardial perfusion by contrast echocardiography.

Sharp Dissection versus Electrocautery for Radial Artery Harvesting

PubMed Central

Marzban, Mehrab; Arya, Reza; Mandegar, Mohammad Hossein; Karimi, Abbas Ali; Abbasi, Kiomars; Movahed, Namvar; Abbasi, Seyed Hesameddin

2006-01-01

Radial arteries have been increasingly used during the last decade as conduits for coronary artery revascularization. Although various harvesting techniques have been described, there has been little comparative study of arterial damage and patency. A radial artery graft was used in 44 consecutive patients, who were randomly divided into 2 groups. In the 1st group, the radial artery was harvested by sharp dissection and in the 2nd, by electrocautery. These groups were compared with regard to radial artery free flow, harvest time, number of clips used, complications, and endothelial damage. Radial artery free flow before and after intraluminal administration of papaverine was significantly greater in the electrocautery group (84.3 ± 50.7 mL/min and 109.7 ± 68.5 mL/min) than in the sharp-dissection group (52.9 ± 18.3 mL/min and 69.6 ± 28.2 mL/ min) (P =0.003). Harvesting time by electrocautery was significantly shorter (25.4 ± 4.3 min vs 34.4 ± 5.9 min) (P =0.0001). Electrocautery consumed an average of 9.76 clips, versus 22.45 clips consumed by sharp dissection. The 2 groups were not different regarding postoperative complications, except for 3 cases of temporary paresthesia of the thumb in the electrocautery group; histopathologic examination found no endothelial damage. We conclude that radial artery harvesting by electrocautery is faster and more economical than harvesting by sharp dissection and is associated with better intraoperative flow and good preservation of endothelial integrity. PMID:16572861

Combined Endovascular Treatment with Distal Radial Artery Coil Embolization and Angioplasty in Steal Syndrome Associated with Forearm Dialysis Fistula

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tercan, Fahri, E-mail: ftercan@yahoo.com; Koçyiğit, Ali, E-mail: alkoc@yahoo.com; Güney, Bünyamin

PurposeThe present study was performed to define the results of the endovascular treatment with angioplasty and distal radial artery embolization in ischemic steal syndrome associated with forearm arteriovenous accesses.MethodThe cases referred to our interventional radiology unit with symptoms and physical examination findings suggestive of ischemic steal syndrome were retrospectively evaluated first by Doppler ultrasonography, and then by angiography. Cases with proximal artery stenosis were applied angioplasty, and those with steal syndrome underwent coil embolization to distal radial artery.ResultsOf 589 patients who underwent endovascular intervention for dialysis arteriovenous fistulae (AVF)-associated problems, 6 (1.01 %) (5 female, 1 males; mean age 62 (rangemore » 41–78) with forearm fistula underwent combined endovascular treatment for steal syndrome. In addition to steal phenomenon, there were stenosis and/or occlusion in proximal radial and/or ulnar artery in 6 patients concurrently. Embolization of distal radial artery and angioplasty to proximal arterial stenoses were performed in all patients. Ischemic symptoms were eliminated in all patients and the AVF were in use at the time of study. In one patient, ischemic symptoms recurring 6 months later were alleviated by repeat angioplasty of ulnar artery.ConclusionIn palmar arch steal syndrome affecting forearm fistulae, combined distal radial embolization and angioplasty is also an effective treatment method in the presence of proximal radial and ulnar arterial stenoses and occlusions.« less

Optimal wrist angulation shortens time needed for radial artery catheterization: a prospective, randomized, and blinded study.

PubMed

Pandey, R; Ashraf, H; Bhalla, A P; Garg, R

2012-01-01

Optimal wrist position is essential for successful catheterization of the radial artery. We planned to study the success rate of radial artery catheterization at various degrees of wrist extension angulations. This prospective, randomized study was performed in 60 consenting patients aged between 18-65 years and undergoing variable surgeries where the anesthetic management required an arterial catheterization. All patients were randomized into three groups of 20 patients each, according to wrist angulation during radial artery catheterization : either 30 degrees (Group 30), 45 degrees (Group 45), or 60 degrees (Group 60). Three metallic angulated wrist boards with angles of 30 degrees, 45 degrees, and 60 degrees (angle measured with calipers) were prepared, on which patient's wrist was kept at the above-mentioned angles of extension. Radial artery catheterization success rate, catheterization time, and numbers of attempts were recorded. The catheterization time was minimal in group 45 (30.50 +/- 16.82 sec) as compared to 36.00 +/- 14.19 sec and 43.50 +/- 13.80 sec in group 30 and 60, respectively. Radial artery was catheterized at first attempt in 60% of Group 45 and Group 60 patients, and in 50% of Group 30 patients. The arterial catheterization was successful in 14/20 patients in Group 30, 19/20 patients in group 45, and 16/20 patients in group 60. We conclude that a wrist extension of 450 appears to be the optimal wrist joint extension for a successful radial artery cannula insertion.

Reconstructive surgery of true aneurysm of the radial artery: A case report.

PubMed

Erdogan, Sevinc Bayer; Akansel, Serdar; Selcuk, Nehir Tandogar; Aka, Serap Aykut

2018-01-01

True radial artery aneurysms are uncommon pathologies and have an organic cause, unlike trauma-induced false aneurysms. A 52-year-old man presented with a pulsatile mass at the anatomical snuff box area of his left hand. The aneurysm was repaired with reconstructive procedure. Although many posttraumatic and iatrogenic cases of false aneurysm of the radial artery have been reported; there are a few reported cases of a true idiopathic aneurysm. A case of reconstructive surgery for true idiopathic radial artery aneurysm is reported in this paper.

Topical nitroglycerin and lidocaine locally vasodilate the radial artery without affecting systemic blood pressure: a dose-finding phase I study.

PubMed

Majure, David T; Hallaux, Melanie; Yeghiazarians, Yerem; Boyle, Andrew J

2012-10-01

Small radial artery diameter (RAD) and vasospasm are barriers to radial artery cannulation. We performed this study to determine if topical nitroglycerin and/or nitroglycerin plus topical lidocaine increases RAD without affecting systemic blood pressure. This was a randomized, double-blind, placebo-controlled study. In the first visit, to determine the optimal dose of nitroglycerin, subjects were randomized to either 15 or 30 mg nitroglycerin on one wrist and placebo on the other. In visit 2, to assess for any effect of lidocaine on the vasodilator function of nitroglycerin, the same subjects were randomized to 20 mg lidocaine + 30 mg nitroglycerin vs 20 mg lidocaine + placebo, or 40 mg lidocaine + 30 mg nitroglycerin vs 40 mg lidocaine + placebo. In both visits, blood pressure and RAD using ultrasonography were measured for 2 hours. In visit 1, both nitroglycerin groups significantly increased RAD, with greater increases with 30 mg nitroglycerin (P < .01) and no significant increase in RAD in placebo wrists. In visit 2, increase in RAD was significantly greater with 20 mg lidocaine + 30 mg nitroglycerin vs 20 mg lidocaine + placebo (P < .001), and 40 mg lidocaine + 30 mg nitroglycerin vs 40 mg lidocaine + placebo (P < .001), indicating that lidocaine does not alter the effect of nitroglycerin. There were significant increases in RAD seen as early as 30 minutes. There were no significant change in RAD in lidocaine + placebo-treated wrists and no change in blood pressure in any group. Topical nitroglycerin and lidocaine significantly increase RAD within 30 to 60 minutes with no effect on contralateral radial artery or blood pressure, indicating a direct, local effect on the radial artery. (Clinicaltrials.gov number NCT00686231). Copyright © 2012 Elsevier Inc. All rights reserved.

Radial to femoral arterial blood pressure differences in septic shock patients receiving high-dose norepinephrine therapy.

PubMed

Kim, Won Young; Jun, Jong Hun; Huh, Jin Won; Hong, Sang Bum; Lim, Chae-Man; Koh, Younsuck

2013-12-01

The accuracy of arterial blood pressure (ABP) monitoring is crucial in treating septic shock patients. Clinically significant differences in central to peripheral ABP could develop into sepsis during vasopressor therapy. The aim of this study was to investigate the difference between radial (peripheral) and femoral (central) ABP in septic shock patients receiving high-dose norepinephrine (NE) therapy. This prospective observational study comparing simultaneous intra-arterial measurements of radial and femoral ABP was performed at a university-affiliated, tertiary referral center between October 2008 and March 2009. Patients with septic shock who needed continuous blood pressure monitoring and high-dose NE therapy 0.1 µg/kg per minute or greater to maintain mean arterial pressure (MAP) of 65 mmHg or greater were included. Statistical analysis was conducted using the Bland-Altman method for comparison of repeated measures. In total, 250 sets of systolic, mean, and diastolic femoral and radial ABP were recorded at baseline and after NE titration. Arterial blood pressure readings from the radial artery were underestimated compared with those from the femoral artery. Overall bias (mean difference between simultaneous measurements) between radial and femoral MAP was +4.9 mmHg; however, during high-dose NE therapy, the bias increased to +6.2 mmHg (95% limits of agreement: -6.0 to +18.3 mmHg). Clinically significant radial-femoral MAP differences (MAP ≥5 mmHg) occurred in up to 62.2% of patients with high-dose NE therapy. Radial artery pressure frequently underestimates central pressure in septic shock patients receiving high-dose NE therapy. Femoral arterial pressure monitoring may be more appropriate when high-dose NE therapy is administered.

A Fiber Bragg Grating Sensor for Radial Artery Pulse Waveform Measurement.

PubMed

Jia, Dagong; Chao, Jing; Li, Shuai; Zhang, Hongxia; Yan, Yingzhan; Liu, Tiegen; Sun, Ye

2018-04-01

In this paper, we report the design and experimental validation of a novel optical sensor for radial artery pulse measurement based on fiber Bragg grating (FBG) and lever amplification mechanism. Pulse waveform analysis is a diagnostic tool for clinical examination and disease diagnosis. High fidelity radial artery pulse waveform has been investigated in clinical studies for estimating central aortic pressure, which is proved to be predictors of cardiovascular diseases. As a three-dimensional cylinder, the radial artery needs to be examined from different locations to achieve optimal pulse waveform for estimation and diagnosis. The proposed optical sensing system is featured as high sensitivity and immunity to electromagnetic interference for multilocation radial artery pulse waveform measurement. The FBG sensor can achieve the sensitivity of 8.236 nm/N, which is comparable to a commonly used electrical sensor. This FBG-based system can provide high accurate measurement, and the key characteristic parameters can be then extracted from the raw signals for clinical applications. The detecting performance is validated through experiments guided by physicians. In the experimental validation, we applied this sensor to measure the pulse waveforms at various positions and depths of the radial artery in the wrist according to the diagnostic requirements. The results demonstrate the high feasibility of using optical systems for physiological measurement and using this FBG sensor for radial artery pulse waveform in clinical applications.

A novel approach to reduce radial artery occlusion after transradial catheterization: postprocedural/prehemostasis intra-arterial nitroglycerin.

PubMed

Dharma, Surya; Kedev, Sasko; Patel, Tejas; Kiemeneij, Ferdinand; Gilchrist, Ian C

2015-04-01

To evaluate whether administration of nitroglycerin through the sheath at the end of a transradial procedure might preserve the patency of the radial artery. Despite the increasing acceptance of transradial approach, radial artery occlusion (RAO) continues to be a vexing problem of transradial access and limits utility of the radial artery as an access site in the future. We conducted a multicenter, prospective, randomized, placebo-controlled, operator-blinded trial and enrolled 1,706 patients who underwent transradial catheterization in three experienced radial centers. Patients were randomized to receive either 500 µg nitroglycerin (n=853) or placebo (n=853), given intra-arterially through the sheath at the end of the radial procedure. The primary outcome was the incidence of RAO as confirmed by absence of antegrade flow at one day after the transradial procedure evaluated by duplex ultrasound of the radial artery. The use of nitroglycerin, as compared with placebo, reduced the risk of the primary outcome [8.3% vs. 11.7%; odds ratio, 0.62; 95% confidence interval (CI), 0.44-0.87; P=0.006]. From a multivariable analysis, duration of hemostasis was a predictor of RAO (odds ratio, (odds ratio, 3.11; 95% CI, 1.66 to 5.82; P<0.001). There were no significant differences between the groups with respect to the sheath size (P=0.311), number of puncture attempts (P=0.941), duration of hemostasis (P=0.379) and procedural time (P=0.095). The administration of nitroglycerin at the end of a transradial catheterization, reduced the incidence of RAO, examined 1 day after the radial procedure by ultrasound. Postprocedural/prehemostasis pharmacologic regimens may represent a novel target for further investigation to reduce RAO. © 2014 Wiley Periodicals, Inc.

[Role of endothelium-derived nitric oxide in sustained flow-dependent dilatation of human peripheral conduit arteries].

PubMed

Bellien, J; Joannidès, R; Iacob, M; Eltchaninoff, H; Thuillez, Ch

2003-01-01

Endothelial dysfunction is involved in the pathogenesis of cardiovascular diseases and is generally associated to the decrease in arterial nitric oxide (NO) availability. In humans, endothelial function can be evaluated by the post-ischaemic flow-dependent dilatation (FDD) of peripheral conduit arteries which is mainly mediated by the NO release when short duration of reactive hyperaemia are used (3 to 5 min ischaemia). However, recent studies suggest that the role of NO in this response decreases as the duration of the hyperaemic stimulation increases. The aim of the present study was thus, to evaluate, in healthy subjects, the role of NO in the FDD of conduct arteries in response to a sustained stimulation. Radial artery diameter (echotracking) and flow (Doppler) were measured, 7 cm under the elbow line, at baseline and during post-ischaemic hyperaemia (10 min wrist cuff inflation) in 10 healthy subjects (age: 24 +/- 1 years) in control period and after acute blockade of the endothelial NO-synthase by local infusion of NG-monomethyl L-arginine (L-NMMA, brachial artery, 8 mumol/min, 7 min). Endothelium-independent dilatation was studied by mean of sodium nitroprusside infusion (SNP: 5, 10 and 20 nmol/min, 3 min each dose before and after L-NMMA). L-NMMA administration decreased radial artery blood flow at base (Control: 14 +/- 2 vs L-NMMA: 10 +/- 1 ml/min, P < 0.05) and increased radial artery vasodilatation in response to SNP (P < 0.05) thus, demonstrating NO-synthase inhibition. Therefore, after L-NMMA there was a small decrease in radial FDD (Control: base: 2.52 +/- 0.05 mm, FDD: 11.3 +/- 0.6% vs L-NMMA: base: 2.51 +/- 0.04 mm: FDD: 9.0 +/- 0.9%; p < 0.05) without change in hyperaemia. In conclusion, our results demonstrate, in contrast to those obtained after short duration of hyperaemia, that the relative implication of NO in the flow-dependent vasodilatation of peripheral conduit arteries in humans decreases in response to sustained stimulation and suggest, in these experimental conditions, an associated flow-dependent vasodilating mechanism that is unaffected by the NO-synthase inhibition.

Comparison between ultrasound guided technique and digital palpation technique for radial artery cannulation in adult patients: An updated meta-analysis of randomized controlled trials.

PubMed

Bhattacharjee, Sulagna; Maitra, Souvik; Baidya, Dalim K

2018-06-01

Possible advantages and risks associated with ultrasound guided radial artery cannulation in-comparison to digital palpation guided method in adult patients are not fully known. We have compared ultrasound guided radial artery cannulation with digital palpation technique in this meta-analysis. Meta-analysis of randomized controlled trials. Trials conducted in operating room, emergency department, cardiac catheterization laboratory. PubMed and Cochrane Central Register of Controlled Trials (CENTRAL) were searched (from 1946 to 20th November 2017) to identify prospective randomized controlled trials in adult patients. Two-dimensional ultrasound guided radial artery catheterization versus digital palpation guided radial artery cannulation. Overall cannulation success rate, first attempt success rate, time to cannulation and mean number of attempts to successful cannulation. Odds ratio (OR) and standardized mean difference (SMD) or mean difference (MD) with 95% confidence interval (CI) were calculated for categorical and continuous variables respectively. Data of 1895 patients from 10 studies have been included in this meta- analysis. Overall cannulation success rate was similar between ultrasound guided technique and digital palpation [OR (95% CI) 2.01 (1.00, 4.06); p = 0.05]. Ultrasound guided radial artery cannulation is associated with higher first attempt success rate of radial artery cannulation in comparison to digital palpation [OR (95% CI) 2.76 (186, 4.10); p < 0.001]. No difference was seen in time to cannulate [SMD (95% CI) -0.31 (-0.65, 0.04); p = 0.30] and mean number of attempt [MD (95% CI) -0.65 (-1.32, 0.02); p = 0.06] between USG guided technique with palpation technique. Radial artery cannulation by ultrasound guidance may increase the first attempt success rate but not the overall cannulation success when compared to digital palpation technique. However, results of this meta-analysis should be interpreted with caution due presence of heterogeneity. Copyright © 2018 Elsevier Inc. All rights reserved.

A Rare Finding of the Superficial Palmar Arch-Developmental and Clinical Significance

PubMed Central

Saxena, Alok; Agarwal, Kishore Kumar; Ray, Biswabina; Pyrtuh, Samuel

2013-01-01

The ulnar artery provides a major blood supply to the hand in the form of the superficial palmar arch, with the assistance of the radial artery. A rare pattern of the superficial palmar arch was observed in a formalin fixed, male cadaveric left hand. The ulnar artery was only involved in the formation of this arch, which provided three common palmar digital arteries which ran into the second, third and the fourth spaces between the corresponding digits and one proper palmar digital artery which ran along the ulnar side of the little finger. The main trunk of the ulnar artery bifurcated to supply the thumb and the index finger. The superficial branch of the radial artery did not participate in the arch formation. The arch was completed by the radial artery proper on the dorsolateral surface of the hand, after joining the point of bifuracation of the ulnar artery. PMID:23730652

Gaussian fitting for carotid and radial artery pressure waveforms: comparison between normal subjects and heart failure patients.

PubMed

Liu, Chengyu; Zheng, Dingchang; Zhao, Lina; Liu, Changchun

2014-01-01

It has been reported that Gaussian functions could accurately and reliably model both carotid and radial artery pressure waveforms (CAPW and RAPW). However, the physiological relevance of the characteristic features from the modeled Gaussian functions has been little investigated. This study thus aimed to determine characteristic features from the Gaussian functions and to make comparisons of them between normal subjects and heart failure patients. Fifty-six normal subjects and 51 patients with heart failure were studied with the CAPW and RAPW signals recorded simultaneously. The two signals were normalized first and then modeled by three positive Gaussian functions, with their peak amplitude, peak time, and half-width determined. Comparisons of these features were finally made between the two groups. Results indicated that the peak amplitude of the first Gaussian curve was significantly decreased in heart failure patients compared with normal subjects (P<0.001). Significantly increased peak amplitude of the second Gaussian curves (P<0.001) and significantly shortened peak times of the second and third Gaussian curves (both P<0.001) were also presented in heart failure patients. These results were true for both CAPW and RAPW signals, indicating the clinical significance of the Gaussian modeling, which should provide essential tools for further understanding the underlying physiological mechanisms of the artery pressure waveform.

Energy harvesting from arterial blood pressure for powering embedded brain sensors

NASA Astrophysics Data System (ADS)

Nanda, Aditya; Karami, M. Amin

2016-04-01

This paper investigates energy harvesting from arterial blood pressure via the piezoelectric effect by using a novel streaked cylinder geometry for the purpose of powering embedded micro-sensors in the brain. Initially, we look at the energy harvested by a piezoelectric cylinder placed inside an artery acted upon by blood pressure. Such an arrangement would be tantamount to constructing a stent out of piezoelectric materials. A stent is a cylinder placed in veins and arteries to prevent obstruction in blood flow. The governing equations of a conductor coated piezoelectric cylinder are obtained using Hamilton's principle. Pressure acting in arteries is radially directed and this is used to simplify the modal analysis and obtain the transfer function relating pressure to the induced voltage across the surface of the harvester. The power harvested by the cylindrical harvester is obtained for different shunt resistances. Radially directed pressure occurs elsewhere and we also look at harvesting energy from oil flow in pipelines. Although the energy harvested by the cylindrical energy harvester is significant at resonance, the natural frequency of the system is found to be very high. To decrease the natural frequency, we propose a novel streaked stent design by cutting it along the length, transforming it to a curved plate and decreasing the natural frequency. The governing equations corresponding to the new geometry are derived using Hamilton's principle and modal analysis is used to obtain the transfer function.

Assessing mental stress from the photoplethysmogram: a numerical study

PubMed Central

Charlton, Peter H; Celka, Patrick; Farukh, Bushra; Chowienczyk, Phil; Alastruey, Jordi

2018-01-01

Abstract Objective: Mental stress is detrimental to cardiovascular health, being a risk factor for coronary heart disease and a trigger for cardiac events. However, it is not currently routinely assessed. The aim of this study was to identify features of the photoplethysmogram (PPG) pulse wave which are indicative of mental stress. Approach: A numerical model of pulse wave propagation was used to simulate blood pressure signals, from which simulated PPG pulse waves were estimated using a transfer function. Pulse waves were simulated at six levels of stress by changing the model input parameters both simultaneously and individually, in accordance with haemodynamic changes associated with stress. Thirty-two feature measurements were extracted from pulse waves at three measurement sites: the brachial, radial and temporal arteries. Features which changed significantly with stress were identified using the Mann–Kendall monotonic trend test. Main results: Seventeen features exhibited significant trends with stress in measurements from at least one site. Three features showed significant trends at all three sites: the time from pulse onset to peak, the time from the dicrotic notch to pulse end, and the pulse rate. More features showed significant trends at the radial artery (15) than the brachial (8) or temporal (7) arteries. Most features were influenced by multiple input parameters. Significance: The features identified in this study could be used to monitor stress in healthcare and consumer devices. Measurements at the radial artery may provide superior performance than the brachial or temporal arteries. In vivo studies are required to confirm these observations. PMID:29658894

Longitudinal changes in late systolic cardiac load and serum NT-proBNP levels in healthy middle-aged Japanese men.

PubMed

Tomiyama, Hirofumi; Nishikimi, Toshio; Matsumoto, Chisa; Kimura, Kazutaka; Odaira, Mari; Shiina, Kazuki; Yamashina, Akira

2015-04-01

We determined whether any significant association exists between change in late systolic cardiac load with time, estimated by radial pressure waveform analysis, and development of cardiac hemodynamic stress in individuals with preserved cardiac function. Brachial-ankle pulse wave velocity, radial augmentation index (rAI), first peak of the radial pressure waveform (SP1), systolic and pulse pressure at the second peak of the radial pressure waveform (SP2 and PP2), and serum levels of N-terminal fragment B-type natriuretic peptide (NT-proBNP) were measured at the start (first examination) and at the end (second examination) of this 3-year study in healthy Japanese men (n = 1,851). A stepwise multivariate linear regression analysis demonstrated that among the parameters of radial pressure waveform analysis and markers of arterial stiffness analyzed, only PP2 was significantly associated with serum NT-proBNP levels in study participants at both the first and second examinations. Furthermore, among the parameters analyzed, only change in PP2 was significantly correlated with the change in serum NT-proBNP levels during the study period (beta = 0.131, P < 0.001). Sustained late systolic cardiac load might be a more significant determinant of the development of cardiac hemodynamic stress than sustained early systolic cardiac load or arterial stiffening in individuals with preserved cardiac function. © American Journal of Hypertension, Ltd 2014. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Transfer function-derived central pressure and cardiovascular disease events: the Framingham Heart Study.

PubMed

Mitchell, Gary F; Hwang, Shih-Jen; Larson, Martin G; Hamburg, Naomi M; Benjamin, Emelia J; Vasan, Ramachandran S; Levy, Daniel; Vita, Joseph A

2016-08-01

Relations between central pulse pressure (PP) or pressure amplification and major cardiovascular disease (CVD) events are controversial. Estimates of central aortic pressure derived using radial artery tonometry and a generalized transfer function may better predict CVD risk beyond the predictive value of brachial SBP. Augmentation index, central SBP, central PP, and central-to-peripheral PP amplification were evaluated using radial artery tonometry and a generalized transfer function as implemented in the SphygmoCor device (AtCor Medical, Itasca, Illinois, USA). We used proportional hazards models to examine relations between central hemodynamics and first-onset major CVD events in 2183 participants (mean age 62 years, 58% women) in the Framingham Heart Study. During median follow-up of 7.8 (limits 0.2-8.9) years, 149 participants (6.8%) had an incident event. Augmentation index (P = 0.6), central aortic systolic pressure (P = 0.20), central aortic PP (P = 0.24), and PP amplification (P = 0.15) were not related to CVD events in multivariable models that adjusted for age, sex, brachial cuff systolic pressure, use of antihypertensive therapy, total and high-density lipoprotein cholesterol concentrations, smoking, and presence of diabetes. In a model that included standard risk factors, model fit was improved (P = 0.03) when brachial systolic pressure was added after central, whereas model fit was not improved (P = 0.30) when central systolic pressure was added after brachial. After considering standard risk factors, including brachial cuff SBP, augmentation index, central PP and PP amplification derived using radial artery tonometry, and a generalized transfer function were not predictive of CVD risk.

Comparison of a priori versus provisional heparin therapy on radial artery occlusion after transradial coronary angiography and patent hemostasis (from the PHARAOH Study).

PubMed

Pancholy, Samir B; Bertrand, Olivier F; Patel, Tejas

2012-07-15

Systemic anticoagulation decreases the risk of radial artery occlusion (RAO) after transradial catheterization and standard occlusive hemostasis. We compared the efficacy and safety of provisional heparin use only when the technique of patent hemostasis was not achievable to standard a priori heparin administration after radial sheath introduction. Patients referred for coronary angiography were randomized in 2 groups. In the a priori group, 200 patients received intravenous heparin (50 IU/kg) immediately after sheath insertion. In the provisional group, 200 patients did not receive heparin during the procedure. After sheath removal, hemostasis was obtained using a TR band (Terumo corporation, Tokyo, Japan) with a plethysmography-guided patent hemostasis technique. In the provisional group, no heparin was given if radial artery patency could be obtained and maintained. If radial patency was not achieved, a bolus of heparin (50 IU/kg) was given. Radial artery patency was evaluated at 24 hours (early RAO) and 30 days after the procedure (late RAO) by plethysmography. Patent hemostasis was obtained in 67% in the a priori group and 74% in the provisional group (p = 0.10). Incidence of RAO remained similar in the 2 groups at the early (7.5% vs 7.0%, p = 0.84) and late (4.5% vs 5.0%, p = 0.83) evaluations. Women, patients with diabetes, patients having not received heparin, and patients without radial artery patency during hemostasis had more RAO. By multivariate analysis, patent radial artery during hemostasis (odds ratio [OR] 0.03, 95% confidence interval [CI] 0.004 to 0.28, p = 0.002) and diabetes (OR 11, 95% CI 3 to 38,p <0.0001) were independent predictors of late RAO, whereas heparin was not (OR 0.45 95% CI 0.13 to 1.54, p = 0.20). In conclusion, our results suggest that maintenance of radial artery patency during hemostasis is the most important parameter to decrease the risk of RAO. In selected cases, provisional use of heparin appears feasible and safe when patent hemostasis is maintained. Copyright © 2012 Elsevier Inc. All rights reserved.

Comparison of the feasibility and effectiveness of transradial coronary angiography via right versus left radial artery approaches (from the PREVAIL Study).

PubMed

Pelliccia, Francesco; Trani, Carlo; Biondi-Zoccai, Giuseppe G L; Nazzaro, Marco; Berni, Andrea; Patti, Giuseppe; Patrizi, Roberto; Pironi, Bruno; Mazzarotto, Pietro; Gioffrè, Gaetano; Speciale, Giulio; Pristipino, Christian

2012-09-15

It remains undefined if transradial coronary angiography from a right or left radial arterial approach differs in real-world practice. To address this issue, we performed a subanalysis of the PREVAIL study. The PREVAIL study was a prospective, multicenter, observational survey of unselected consecutive patients undergoing invasive cardiovascular procedures over a 1-month observation period, specifically aimed at assessing the outcomes of radial approach in the contemporary real world. The choice of arterial approach was left to the discretion of the operator. Prespecified end points of this subanalysis were procedural characteristics. Of 1,052 patients consecutively enrolled, 509 patients underwent transradial catheterization, 304 with a right radial and 205 with a left radial approach. Procedural success rates were similar between the 2 groups. Compared to the left radial group, the right radial group had longer procedure duration (46 ± 29 vs 33 ± 24 minutes, p <0.0001) and fluoroscopy time (765 ± 787 vs 533 ± 502, p <0.0001). At multivariate analysis, including a parsimonious propensity score for the choice of left radial approach, duration of procedure (beta coefficient 11.38, p <0.001) and total dose-area product (beta coefficient 11.38, p <0.001) were independently associated with the choice of the left radial artery approach. The operator's proficiency in right/left radial approach did not influence study results. In conclusion, right and left radial approaches are feasible and effective to perform percutaneous procedures. In the contemporary real world, however, the left radial route is associated with shorter procedures and lower radiologic exposure than the right radial approach, independently of an operator's proficiency. Copyright © 2012 Elsevier Inc. All rights reserved.

Radial Artery Approach to Salvage Nonmaturing Radiocephalic Arteriovenous Fistulas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hsieh, Mu-Yang; Lin, Lin; Tsai, Kuei-Chin

2013-08-01

PurposeTo evaluate the usefulness of an approach through the radial artery distal to the arteriovenous anastomosis for salvaging nonmaturing radiocephalic arteriovenous fistulas.MethodsProcedures that fulfilled the following criteria were retrospectively reviewed: (1) autogenous radiocephalic fistulas, (2) fistulas less than 3 months old, (3) distal radial artery approach for salvage. From 2005 to 2011, a total of 51 patients fulfilling the above criteria were enrolled. Outcome variables were obtained from angiographic, clinical and hemodialysis records, including the success, complication, and primary and secondary patency rates.ResultsThe overall anatomical and clinical success rates for the distal radial artery approach were 96 and 94 %,more » respectively. The average procedure time was 36 {+-} 19 min. Six patients (12 %) experienced minor complications as a result of extravasations. No arterial complication or puncture site complication was noted. The postinterventional 6-month primary patency rate was 51 %, and the 6-month secondary patency rate was 90 %. When the patients were divided into a stenosed group (20 patients) and an occluded group (31 patients), there were no differences in the success rate, complication rate, or primary and secondary patency rates.ConclusionAn approach through the radial artery distal to the arteriovenous anastomosis is an effective and safe alternative for the salvage of nonmaturing radiocephalic arteriovenous fistulas, even for occluded fistulas.« less

Temporary cerebral revascularization using a radial artery in the hand-eyeshade posture: technical note.

PubMed

Hiramoto, Jun; Tanaka, Yuichiro

2014-06-17

Kamiyama introduced a unique method of temporary cerebral revascularization using a radial artery graft (RAG) in his technical review. We tried original method with Sugita frame, and pointed out some disadvantages that include to avoid taking instruments or hands in and out, stability of hands, and unrestricted usage of brain retractors during temporary bypass between radial artery and M2 potion of middle cerebral artery (RA-M2 bypass). To solve those disadvantages, especially for Sugita head frame users, we here present a modified Kamiyama's method of temporary cerebral revascularization with the forearm elevated over the face like as hand-eyeshade posture.

An avulsed radial artery with a high take-off.

PubMed

Rojas-Marte, Geurys; Chen, On; Verma, Shivani; Rao, Atul; Shani, Jacob; Ayzenberg, Sergey

2015-04-01

A 63-year-old female was diagnosed with severe aortic stenosis, who underwent a diagnostic coronary angiography via transradial approach prior an aortic-valve replacement. After imaging the left coronary system, entrapment of the diagnostic catheter was encountered as a result of spasm of the radial artery. An arteriogram of the arm revealed an anatomical variation in the radial artery (high take-off). Several attempts to remove the entrapped catheter resulted in avulsion of the artery, which was managed successfully with coil embolization. To our knowledge, no such complication has been reported. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Prevalence and characteristics of atherosclerosis and peripheral arterial disease in a Chinese population of Inner Mongolia.

PubMed

Wang, Y; Li, J; Zhao, D; Wei, Y; Hou, L; Hu, D; Xu, Y

2011-01-01

To investigate the relationship between brachial ankle pulse wave velocity (BaPWV), radial augmentation index (radial AI), ankle-brachial index (ABI), and carotid intima-media thickness (carotid-IMT), and to study the prevalence and characteristics of atherosclerosis and peripheral arterial disease in a Chinese population of Inner Mongolia. Participants were recruited from Inner Mongolia in China through cluster multistage and random sampling. BaPWV, radial AI, ABI, and carotid-IMT values were measured in each subject. A total of 1,236 participants from natural population of Inner Mongolia in China were included in this study. The average ABI value was 1.082 ± 0.093. The average values of common carotid, internal carotid, and carotid artery bifurcation IMT were 0.70 ± 0.21, 0.77 ± 0.24, and 0.78 ± 0.25 mm, respectively. The average value of BaPWV was 1450.5 ± 301.5 cm/s. The average value of radial AI was 78.9 ± 16.8 %. BaPWV, radial AI, and carotid-IMT values were positively correlated with ages significantly. BaPWV values were positively correlated with radial AI significantly. BaPWV values were positively correlated with values of common carotid, internal carotid, and carotid artery bifurcation IMT respectively. Radial AI values were positively correlated with the values of common carotid, internal carotid, and carotid artery bifurcation IMT respectively. A U-shaped relationship was observed that radial AI values were decreased at first and then increased as ABI values increased. The data suggests that BaPWV, radial AI, and carotid-IMT values are positively correlated with each other, and AI values are correlated with ABI values in a U-shaped curve in a Chinese population of Inner Mongolia.

Arterial stiffness estimation based photoplethysmographic pulse wave analysis

NASA Astrophysics Data System (ADS)

Huotari, Matti; Maatta, Kari; Kostamovaara, Juha

2010-11-01

Arterial stiffness is one of the indices of vascular healthiness. It is based on pulse wave analysis. In the case we decompose the pulse waveform for the estimation and determination of arterial elasticity. Firstly, optically measured with photoplethysmograph and then investigating means by four lognormal pulse waveforms for which we can find very good fit between the original and summed decomposed pulse wave. Several studies have demonstrated that these kinds of measures predict cardiovascular events. While dynamic factors, e.g., arterial stiffness, depend on fixed structural features of the vascular wall. Arterial stiffness is estimated based on pulse wave decomposition analysis in the radial and tibial arteries. Elucidation of the precise relationship between endothelial function and vascular stiffness awaits still further study.

A coincidental variation of the axillary artery: the brachioradial artery and the aberrant posterior humeral circumflex artery passing under the tendon of the latissimus dorsi muscle

PubMed Central

Konarik, Marek; Kachlik, David; Baca, Vaclav

2014-01-01

A case of anomalous terminal branching of the axillary artery was encountered and described in a left upper limb of a male cadaver. A series of 214 upper limbs of Caucasian race was dissected. A variant artery, stemming from the very end of the axillary artery followed a superficial course distally. It passed the cubital fossa, ran on the lateral side of the forearm as usual radial artery, crossed ventrally to the palm and terminated in the deep palmar arch. This vessel is a case of the brachioradial artery (incorrectly termed as the “radial artery with high origin”). Moreover, it was associated with another variation, concerning the aberrant posterior humeral circumflex artery passing under the tendon of the latissimus dorsi muscle. The anatomical knowledge of the axillary region is essential for radiodiagnostic, surgical and traumatologic procedures. The superficially located artery brings an elevated danger of heavy bleeding in all unexpected situations, its variant branching can cause problems in radial catheterization procedures and the anomalously coursing other arterial variant poses an elevated danger in surgical procedures concerning the surgical neck of humerus. PMID:25428677

Harmonic scalpel versus electrocautery for harvest of radial artery conduits: Reduced risk of spasm and intimal injury on optical coherence tomography

PubMed Central

Brazio, Philip S.; Laird, Patrick C.; Xu, Chenyang; Gu, Junyan; Burris, Nicholas S.; Brown, Emile N.; Kon, Zachary N.; Poston, Robert S.

2009-01-01

Objective Vasospasm is the primary obstacle to widespread adoption of the radial artery as a conduit in coronary artery bypass grafting. We used optical coherence tomography, a catheter-based intravascular imaging modality, to measure the degree of radial artery spasm induced by means of harvest with electrocautery or a harmonic scalpel in patients undergoing coronary artery bypass grafting. Methods Radial arteries were harvested from 44 consecutive patients with a harmonic scalpel (n = 15) or electrocautery (n = 29). Vessels were imaged before harvesting and after removal from the arm, with saphenous vein tracts serving as internal controls. Optical coherence tomographic findings for the degree of harvesting-induced injury were validated against histologic measures. Results Optical coherence tomographic measures of endovascular dimensions and injury correlated strongly with histologic findings. Mean luminal volume, a measure of vasospasm, decreased significantly less after harvesting with a harmonic scalpel (9% ± 7%) than with electrocautery (35% ± 6%, P = .015). Completely intact intima was present in 11 (73%) of 15 radial arteries harvested with a harmonic scalpel (73%) compared with 9 of 29 arteries harvested by means of electrocautery (31%, P = .011). Intraoperative flow measurements and patency rates at 5 days postoperatively were not significantly different among groups. Conclusions Optical coherence tomography provides a level of speed and accuracy for quantifying endothelial injury and vasospasm that has not been described for any other modality, suggesting potential as an intraoperative quality assurance tool. Our optical coherence tomographic findings suggest that the harmonic scalpel induces less spasm and intimal injury compared with electrocautery. PMID:19026820

Photoplethysmography using a smartphone application for assessment of ulnar artery patency: a randomized clinical trial

PubMed Central

Di Santo, Pietro; Harnett, David T.; Simard, Trevor; Ramirez, F. Daniel; Pourdjabbar, Ali; Yousef, Altayyeb; Moreland, Robert; Bernick, Jordan; Wells, George; Dick, Alexander; Le May, Michel; Labinaz, Marino; So, Derek; Motazedian, Pouya; Jung, Richard G.; Chandrasekhar, Jaya; Mehran, Roxana; Chong, Aun-Yeong

2018-01-01

BACKGROUND: Radial artery access is commonly performed for coronary angiography and invasive hemodynamic monitoring. Despite limitations in diagnostic accuracy, the modified Allen test (manual occlusion of radial and ulnar arteries followed by release of the latter and assessment of palmar blush) is used routinely to evaluate the collateral circulation to the hand and, therefore, to determine patient eligibility for radial artery access. We sought to evaluate whether a smartphone application may provide a superior alternative to the modified Allen test. METHODS: We compared the modified Allen test with a smartphone heart rate–monitoring application (photoplethysmography readings detected using a smartphone camera lens placed on the patient’s index finger) in patients undergoing a planned cardiac catheterization. Test order was randomly assigned in a 1:1 fashion. All patients then underwent conventional plethysmography of the index finger, followed by Doppler ultrasonography of the radial and ulnar arteries (the diagnostic standard). The primary outcome was diagnostic accuracy of the heart rate–monitoring application. RESULTS: Among 438 patients who were included in the study, we found that the heart rate–monitoring application had a superior diagnostic accuracy compared with the modified Allen test (91.8% v. 81.7%, p = 0.002), attributable to its greater specificity (93.0% v. 82.8%, p = 0.001). We also found that this application had greater diagnostic accuracy for assessment of radial or ulnar artery patency in the ipsilateral and contralateral wrist (94.0% v. 84.0%, p < 0.001). INTERPRETATION: A smartphone application used at the bedside was diagnostically superior to traditional physical examination for confirming ulnar patency before radial artery access. This study highlights the potential for smartphone-based diagnostics to aid in clinical decision-making at the patient’s bedside. Trial registration: Clinicaltrials.gov, no. NCT02519491. PMID:29615421

Manual Versus Mechanical Compression of the Radial Artery After Transradial Coronary Angiography: The MEMORY Multicenter Randomized Trial.

PubMed

Petroglou, Dimitrios; Didagelos, Matthaios; Chalikias, Georgios; Tziakas, Dimitrios; Tsigkas, Grigorios; Hahalis, Georgios; Koutouzis, Michael; Ntatsios, Antonios; Tsiafoutis, Ioannis; Hamilos, Michael; Kouparanis, Antonios; Konstantinidis, Nikolaos; Sofidis, Georgios; Pancholy, Samir B; Karvounis, Haralambos; Bertrand, Olivier Francois; Ziakas, Antonios

2018-06-11

The aim of this study was to compare manual versus mechanical compression of the radial artery after coronary angiography via transradial access regarding radial artery occlusion (RAO), access-site bleeding complications, and duration of hemostasis. Hemostasis of the radial artery after sheath removal can be achieved either by manual compression at the puncture site or by using a mechanical hemostasis device. Because mechanical compression exerts a more stable, continuous pressure on the artery, it could be hypothesized that it is more effective compared with manual compression regarding hemostasis time, bleeding, and RAO risks. A total of 589 patients undergoing diagnostic coronary angiography by transradial access with a 5-F sheath were randomized in a 1:1 ratio to receive either manual or mechanical patent hemostasis of the radial artery. Radial artery patency was evaluated by color duplex ultrasonography 24 h after the procedure. The primary endpoint was early RAO at 24 h. Secondary endpoints included access-site bleeding complications and duration of hemostasis. Thirty-six (12%) early RAOs occurred in the manual group, and 24 (8%) occurred in the mechanical group (p = 0.176). There were no significant differences between the 2 groups regarding access-site bleeding complications (hematoma, 52 [17%] vs. 50 [18%]; p = 0.749; bleedings, 8 [3%] vs. 9 [3%]; p = 1.000). Duration of hemostasis was significantly shorter in the manual group (22 ± 34 min vs. 119 ± 72 min with mechanical compression; p < 0.001). Manual and mechanical compression resulted in similar rates of early RAO, although the total duration of hemostasis was significantly shorter in the manual group. Copyright © 2018 American College of Cardiology Foundation. All rights reserved.

Photoplethysmography using a smartphone application for assessment of ulnar artery patency: a randomized clinical trial.

PubMed

Di Santo, Pietro; Harnett, David T; Simard, Trevor; Ramirez, F Daniel; Pourdjabbar, Ali; Yousef, Altayyeb; Moreland, Robert; Bernick, Jordan; Wells, George; Dick, Alexander; Le May, Michel; Labinaz, Marino; So, Derek; Motazedian, Pouya; Jung, Richard G; Chandrasekhar, Jaya; Mehran, Roxana; Chong, Aun-Yeong; Hibbert, Benjamin

2018-04-03

Radial artery access is commonly performed for coronary angiography and invasive hemodynamic monitoring. Despite limitations in diagnostic accuracy, the modified Allen test (manual occlusion of radial and ulnar arteries followed by release of the latter and assessment of palmar blush) is used routinely to evaluate the collateral circulation to the hand and, therefore, to determine patient eligibility for radial artery access. We sought to evaluate whether a smartphone application may provide a superior alternative to the modified Allen test. We compared the modified Allen test with a smartphone heart rate-monitoring application (photoplethysmography readings detected using a smartphone camera lens placed on the patient's index finger) in patients undergoing a planned cardiac catheterization. Test order was randomly assigned in a 1:1 fashion. All patients then underwent conventional plethysmography of the index finger, followed by Doppler ultrasonography of the radial and ulnar arteries (the diagnostic standard). The primary outcome was diagnostic accuracy of the heart rate-monitoring application. Among 438 patients who were included in the study, we found that the heart rate-monitoring application had a superior diagnostic accuracy compared with the modified Allen test (91.8% v. 81.7%, p = 0.002), attributable to its greater specificity (93.0% v. 82.8%, p = 0.001). We also found that this application had greater diagnostic accuracy for assessment of radial or ulnar artery patency in the ipsilateral and contralateral wrist (94.0% v. 84.0%, p < 0.001). A smartphone application used at the bedside was diagnostically superior to traditional physical examination for confirming ulnar patency before radial artery access. This study highlights the potential for smartphone-based diagnostics to aid in clinical decision-making at the patient's bedside. Trial registration: Clinicaltrials.gov, no. NCT02519491. © 2018 Joule Inc. or its licensors.

Nonenhanced MR angiography of the pulmonary arteries using single-shot radial quiescent-interval slice-selective (QISS): a technical feasibility study.

PubMed

Edelman, Robert R; Silvers, Robert I; Thakrar, Kiran H; Metzl, Mark D; Nazari, Jose; Giri, Shivraman; Koktzoglou, Ioannis

2017-06-30

For evaluation of the pulmonary arteries in patients suspected of pulmonary embolism, CT angiography (CTA) is the first-line imaging test with contrast-enhanced MR angiography (CEMRA) a potential alternative. Disadvantages of CTA include exposure to ionizing radiation and an iodinated contrast agent, while CEMRA is sensitive to respiratory motion and requires a gadolinium-based contrast agent. The primary goal of our technical feasibility study was to evaluate pulmonary arterial conspicuity using breath-hold and free-breathing implementations of a recently-developed nonenhanced approach, single-shot radial quiescent-interval slice-selective (QISS) MRA. Breath-hold and free-breathing, navigator-gated versions of radial QISS MRA were evaluated at 1.5 Tesla in three healthy subjects and 11 patients without pulmonary embolism or arterial occlusion by CTA. Images were scored by three readers for conspicuity of the pulmonary arteries through the level of the segmental branches. In addition, one patient with pulmonary embolism was imaged. Scan time for a 54-slice acquisition spanning the pulmonary arteries was less than 2 minutes for breath-hold QISS, and less than 3.4 min using free-breathing QISS. Pulmonary artery branches through the segmental level were conspicuous with either approach. Free-breathing scans showed only mild blurring compared with breath-hold scans. For both readers, less than 1% of pulmonary arterial segments were rated as "not seen" for breath-hold and navigator-gated QISS, respectively. In subjects with atrial fibrillation, single-shot radial QISS consistently depicted the pulmonary artery branches, whereas navigator-gated 3D balanced steady-state free precession showed motion artifacts. In one patient with pulmonary embolism, radial QISS demonstrated central pulmonary emboli comparably to CEMRA and CTA. The thrombi were highly conspicuous on radial QISS images, but appeared subtle and were not prospectively identified on scout images acquired using a single-shot bSSFP acquisition. In this technical feasibility study, both breath-hold and free-breathing single-shot radial QISS MRA enabled rapid, consistent demonstration of the pulmonary arteries through the level of the segmental branches, with only minimal artifacts from respiratory motion and cardiac arrhythmias. Based on these promising initial results, further evaluation in patients with suspected pulmonary embolism appears warranted.

Activation of the CXCL16/CXCR6 Pathway by Inflammation Contributes to Atherosclerosis in Patients with End-stage Renal Disease.

PubMed

Hu, Ze Bo; Chen, Yan; Gong, Yu Xiang; Gao, Min; Zhang, Yang; Wang, Gui Hua; Tang, Ri Ning; Liu, Hong; Liu, Bi Cheng; Ma, Kun Ling

2016-01-01

Background: Chronic inflammation plays a critical role in the progression of atherosclerosis (AS). This study aimed to determine the effects of the CXC chemokine ligand 16 (CXCL16)/CXC chemokine receptor 6 (CXCR6) pathway on cholesterol accumulation in the radial arteries of end-stage renal disease (ESRD) patients with concomitant microinflammation and to further investigate the potential effects of the purinergic receptor P2X ligand-gated ion channel 7 (P2X7R). Methods: Forty-three ESRD patients were divided into the control group (n=17) and the inflamed group (n=26) based on plasma C-reactive protein (CRP) levels. Biochemical indexes and lipid profiles of the patients were determined. Surgically removed tissues from the radial arteries of patients receiving arteriovenostomy were used for preliminary evaluation of AS. Haematoxylin-eosin (HE) and Filipin staining were performed to assess foam cell formation. CXCL16/CXCR6 pathway-related protein expression, P2X7R protein expression and the expression of monocyte chemotactic protein-1 (MCP-1), tumour necrosis factor-α (TNF-α), and CD68 were detected by immunohistochemical and immunofluorescence staining. Results: Inflammation increased both MCP-1 and TNF-α expression and macrophage infiltration in radial arteries. Additionally, foam cell formation significantly increased in the radial arteries of the inflamed group compared to that of the controls. Further analysis showed that protein expression of CXCL16, CXCR6, disintegrin and metalloproteinase-10 (ADAM10) in the radial arteries of the inflamed group was significantly increased. Furthermore, CXCL16 expression was positively correlated with P2X7R expression in the radial arteries of ESRD patients. Conclusions: Inflammation contributed to foam cell formation in the radial arteries of ESRD patients via activation of the CXCL16/CXCR6 pathway, which may be regulated by P2X7R.

A semi-automatic framework of measuring pulmonary arterial metrics at anatomic airway locations using CT imaging

NASA Astrophysics Data System (ADS)

Jin, Dakai; Guo, Junfeng; Dougherty, Timothy M.; Iyer, Krishna S.; Hoffman, Eric A.; Saha, Punam K.

2016-03-01

Pulmonary vascular dysfunction has been implicated in smoking-related susceptibility to emphysema. With the growing interest in characterizing arterial morphology for early evaluation of the vascular role in pulmonary diseases, there is an increasing need for the standardization of a framework for arterial morphological assessment at airway segmental levels. In this paper, we present an effective and robust semi-automatic framework to segment pulmonary arteries at different anatomic airway branches and measure their cross-sectional area (CSA). The method starts with user-specified endpoints of a target arterial segment through a custom-built graphical user interface. It then automatically detect the centerline joining the endpoints, determines the local structure orientation and computes the CSA along the centerline after filtering out the adjacent pulmonary structures, such as veins or airway walls. Several new techniques are presented, including collision-impact based cost function for centerline detection, radial sample-line based CSA computation, and outlier analysis of radial distance to subtract adjacent neighboring structures in the CSA measurement. The method was applied to repeat-scan pulmonary multirow detector CT (MDCT) images from ten healthy subjects (age: 21-48 Yrs, mean: 28.5 Yrs; 7 female) at functional residual capacity (FRC). The reproducibility of computed arterial CSA from four airway segmental regions in middle and lower lobes was analyzed. The overall repeat-scan intra-class correlation (ICC) of the computed CSA from all four airway regions in ten subjects was 96% with maximum ICC found at LB10 and RB4 regions.

Functional characterization of intracellular pH regulators responsible for acid extrusion in human radial artery smooth muscle cells.

PubMed

Lee, Chung-Yi; Tsai, Yi-Ting; Chang, Chung-Yi; Chang, Yi-Yu; Cheng, Tzu-Hurng; Tsai, Chien-Sung; Loh, Shih-Hurng

2014-10-31

Intracellular pH (pHi) is a critical factor influencing many important cellular functions. Acid extrusion carriers such as an Na⁺/H⁺ exchanger (NHE) Na⁺/HCO₃⁻ cotransporter (NBC) and monocarboxylate transporters (MCT) can be activated when cells are in an acidic condition (pHi < 7.1). Human radial artery smooth muscle cells (HRASMC) is an important conduit in coronary artery bypass graft surgery. However, such far, the pHi regulators have not been characterized in HRASMCs. We therefore investigated the mechanism of pHi recovery from intracellular acidosis and alkalosis, induced by NH₄Cl-prepulse and Na-acetate-prepulse, respectively, using intracellular 2',7'-bis(2-carboxethyl)-5(6)- carboxy-fluorescein (BCECF)-fluorescence in HRASMCs. Cultured HRASMCs were derived from the segments of human radial artery that were obtained from patients undergoing bypass grafting. The resting pHi is 7.22 ± 0.03 and 7.17 ± 0.02 for HEPES- (nominally HCO₃⁻-free) and CO₂/HCO₃⁻- buffered solution, respectively. In HEPES-buffered solution, a pHi recovery from induced intracellular acidosis could be blocked completely by 30 μM HOE 694 (3-methylsulfonyl-4-piperidinobenzoyl, guanidine hydrochloride) a specific NHE inhibitor, or by removing [Na⁺]₀. In 3% CO₂/HCO₃⁻-buffered solution, HOE 694 slowed the pHi recovery from the induced intracellular acidosis only, while adding together with DIDS (a specific NBC inhibitor) or removal of [Na⁺]₀ entirely inhibited the acid extrusion. Moreover, α-cyano-4-hydroxycinnamate (CHC; a specific blocker of MCT) blocked the lactate-induced pHi changes. In conclusion, we demonstrate, for the first time, that 3 different pHi regulators responsible for acid extruding, i.e. NHE and NBC, and MCT, are functionally co-existed in cultured HRASMCs.

LASER BIOLOGY AND MEDICINE: Arterial pulse shape measurement using self-mixing effect in a diode laser

NASA Astrophysics Data System (ADS)

Hast, J.; Myllylä, Risto; Sorvoja, H.; Miettinen, J.

2002-11-01

The self-mixing effect in a diode laser and the Doppler technique are used for quantitative measurements of the cardiovascular pulses from radial arteries of human individuals. 738 cardiovascular pulses from 10 healthy volunteers were studied. The Doppler spectrograms reconstructed from the Doppler signal, which is measured from the radial displacement of the radial artery, are compared to the first derivative of the blood pressure signals measured from the middle finger by the Penaz technique. The mean correlation coefficient between the Doppler spectrograms and the first derivative of the blood pressure signals was 0.84, with a standard deviation of 0.05. Pulses with the correlation coefficient less than 0.7 were neglected in the study. Percentage of successfully detected pulses was 95.7%. It is shown that cardiovascular pulse shape from the radial artery can be measured noninvasively by using the self-mixing interferometry.

High-flow bypass with radial artery graft followed by internal carotid artery ligation for large or giant aneurysms of cavernous or cervical portion: clinical results and cognitive performance.

PubMed

Ono, Hideaki; Inoue, Tomohiro; Tanishima, Takeo; Tamura, Akira; Saito, Isamu; Saito, Nobuhito

2018-04-01

High-flow bypass followed by ligation of the internal carotid artery (ICA) is an effective treatment, but the impact of abrupt occlusion of the ICA is unpredictable, especially on postoperative cognitive function. The present study evaluated the clinical results as well as cognitive performances after high-flow bypass using radial artery graft (RAG) with supportive superficial temporal artery (STA)-middle cerebral artery (MCA) bypass, followed by ICA ligation. Ten consecutive patients underwent high-flow bypass surgery for large or giant ICA aneurysms of cavernous or cervical portion. Demographics, clinical information, magnetic resonance (MR) imaging, computed tomography, digital subtraction angiography (DSA), intraoperative somatosensory evoked potentials, neuropsychological examinations including the Wechsler Adult Intelligence Scale-Third Edition and the Wechsler Memory Scale-Revised (WMS-R), and follow-up data were analyzed. The aneurysm was located on the cavernous segment in eight cases and cervical segment in two cases, and mean aneurysm size was 27.9 mm. Postoperative DSA demonstrated robust bypass flow from the external carotid artery to MCA via the RAG, and no anterograde flow into the aneurysm. No patient showed new symptoms after the operation. Follow-up clinical study and MR imaging were performed in nine patients and showed no additional ischemic lesion compared with preoperative imaging. Seven patients completed neuropsychological examinations before and after surgery. All postoperative scores except WMS-R composite memory score slightly improved. High-flow bypass followed by ICA ligation can achieve good clinical outcomes. Successful high-flow bypass using RAG with supportive STA-MCA bypass and ICA ligation does not adversely affect postoperative cognitive function.

Endoscopic saphenous vein and radial harvest: state-of-the-art.

PubMed

Bisleri, Gianluigi; Muneretto, Claudio

2015-11-01

Over the past decade, there has been an increased adoption of minimally invasive techniques for saphenous vein and radial artery procurement during coronary artery bypass surgery, albeit concerns have been raised about the potential detrimental effects of the endoscopic approach when compared with the conventional 'open' technique. The aim of the present review is to analyse the current available techniques and evidence about the impact of an endoscopic approach on conduit quality and clinical outcomes. At present, the available techniques for endoscopic vessel harvesting can be based on a sealed or non-sealed concept, for both saphenous vein and radial artery procurement. Despite the proven advantages of a minimally invasive approach in terms of reduced incidence of wound complications, pain reduction and improved cosmetic results, some studies questioned the impact of this technique in terms of potential graft damage, thus impairing the longevity of the graft itself. Endoscopic conduit harvesting can be performed safely and effectively with the currently available techniques, albeit a careful knowledge of the pitfalls of each technique is mandatory. Since there is ample evidence in literature that a minimally invasive approach for saphenous vein and radial artery procurement is not associated with an increased risk of graft damage and related failure in the mid-long term, the endoscopic technique should be adopted as the approach of choice for saphenous vein and radial artery harvesting in coronary artery bypass graft surgery.

Implementation of radial arterial access for cardiac interventions: a strong case for quality assurance protocols by the nursing staff.

PubMed

Steffenino, Giuseppe; Fabrizi, Mauro De Benedetto; Baralis, Giorgio; Tomatis, Marilena; Mogna, Aldo; Dutto, Monica; Dutto, Maria Stefania; Conte, Laura; Lice, Giulietta; Cavallo, Simona; Porcedda, Brunella

2011-02-01

Radial arterial access is becoming increasingly popular for coronary angiography and angioplasty. The technique is, however, more demanding than femoral arterial access, and hemostasis is not care-free. A quality assurance program was run by our nursing staff, with patient follow-up, to monitor radial arterial access implementation in our laboratory. In 973 consecutive patients, both a hydrophilic sheath and an inflatable bandage for hemostasis were used. Bandage inflation volume and time were both reduced through subsequent data audit and protocol changes (A = 175 patients; B = 297; C = 501). An increase was achieved in the percentage of patients with neither loss of radial pulse nor hematoma of any size (A = 81.3%, B = 90.9%, C = 92.2%, P < 0.001), and no discomfort at all (A = 44.2%, B = 75.1%, C = 89.3%, P < 0.001). Follow-up was available for 965 patients (99%), and in 956, the access site could be re-inspected at least once. There were no vascular complications. Overall, the radial artery pulse was absent at latest follow-up in 0.6% of cases (95% confidence interval 0.21-1.05%). In 460 consecutive patients with complete assessment in protocol C, a palpable arterial pulse was absent in 5% of cases at about 20 h after hemostasis. Barbeau's test was positive in 26.5% of patients (95% confidence interval 22.5-30.6%). They had a significantly lower body weight, a lower systolic blood pressure at hemostasis, and a higher bandage inflation volume; a hematoma of any size and the report of any discomfort were also more frequent. Barbeau's test returned to normal in 30% of them 3-60 days later. Our nurse-led quality assurance program helped us in reducing minor vascular sequelae and improving patient comfort after radial access. Early occlusion of the radial artery as detected by pulse oxymeter is frequent, often reversible, and may be mostly related to trauma/occlusion of the artery during hemostasis. 2011 Italian Federation of Cardiology.

Pseudoaneurysm of the Radial Artery After a Bicycle Fall.

PubMed

Ratschiller, Thomas; Müller, Hannes; Schachner, Thomas; Zierer, Andreas

2018-07-01

We report a case of a 64-year-old man who developed a painful pulsatile mass in the distal forearm after a bicycle fall with fracture of the wrist. Ultrasonography confirmed a 2.5-cm large pseudoaneurysm of the radial artery. The patient underwent surgical exploration. The pseudoaneurysm was resected and the defect in the arterial wall was reconstructed with an autologous saphenous vein patch. We suggest that the double arterial supply of the hand should be preserved whenever possible.

Beat-to-beat agreement of noninvasive tonometric and intra-radial arterial blood pressure during microgravity and hypergravity generated by parabolic flights.

PubMed

Normand, Hervé; Lemarchand, Erick; Arbeille, Philippe; Quarck, Gaëlle; Vaïda, Pierre; Duretete, Arnaud; Denise, Pierre

2007-12-01

Accurate measurement of beat-to-beat arterial blood pressure is essential for understanding the cardiovascular adaptation to weightlessness; however, the intra-arterial standard of beat-to-beat blood pressure measurement has never been used during space flight because of its invasive nature. The aim of the present study was to compare noninvasive radial artery tonometry blood pressure measurement with intra-radial pressure measurement during microgravity and hypergravity generated by parabolic flights. Two study participants, equipped with an intra-radial pressure line on the left arm and a Colin CBM-7000 (Colin Corp., Komaki City, Japan) beat-to-beat pressure measurement apparatus on the right arm, were studied in a supine position, during parabolic flights on board of the Airbus A300 OG of the Centre National d'Etudes Spatiales. The mean and standard deviations of the beat-to-beat difference between tonometric and intra-radial blood pressure were calculated for systolic and diastolic arterial pressure in the three gravity conditions (1g, 0 g and 1.8 g) experienced during parabolic flight. The Colin CBM-7000 met the specifications required by the Association for the Advancement of Medical Instrumentation in the 0 g environment. Gravity, however, significantly affected the difference between tonometric and intra-arterial blood pressure, possibly owing to the effect of gravity on the apparent weight of the device and the corresponding calibration factor. We conclude that the Colin CBM-7000 can be used with confidence during space flight.

Uterine distension differentially affects remodelling and distensibility of the uterine vasculature in non-pregnant rats.

PubMed

Osol, George; Barron, Carolyn; Mandalà, Maurizio

2012-01-01

During pregnancy the mammalian uterine circulation undergoes significant expansive remodelling necessary for normal pregnancy outcome. The underlying mechanisms are poorly defined. The goal of this study was to test the hypothesis that myometrial stretch actively stimulates uterine vascular remodelling by developing a new surgical approach to induce unilateral uterine distension in non-pregnant rats. Three weeks after surgery, which consisted of an infusion of medical-grade silicone into the uterine lumen, main and mesometrial uterine artery and vein length, diameter and distensibility were recorded. Radial artery diameter, distensibility and vascular smooth muscle mitotic rate (Ki67 staining) were also measured. Unilateral uterine distension resulted in significant increases in the length of main uterine artery and vein and mesometrial segments but had no effect on vessel diameter or distensibility. In contrast, there were significant increases in the diameter of the radial arteries associated with the distended uterus. These changes were accompanied by reduced arterial distensibility and increased vascular muscle hyperplasia. In summary, this is the first report to show that myometrial stretch is a sufficient stimulus to induce significant remodelling of uterine vessels in non-pregnant rats. Moreover, the results indicate differential regulation of these growth processes as a function of vessel size and type.

High-permittivity thin dielectric padding improves fresh blood imaging of femoral arteries at 3 T.

PubMed

Lindley, Marc D; Kim, Daniel; Morrell, Glen; Heilbrun, Marta E; Storey, Pippa; Hanrahan, Christopher J; Lee, Vivian S

2015-02-01

Fresh blood imaging (FBI) is a useful noncontrast magnetic resonance angiographic (MRA) method for the assessment of peripheral arterial disease, particularly for imaging patients with poor renal function. Compared with 1.5 T, 3 T enables higher signal-to-noise ratio and/or spatiotemporal resolution in FBI. Indeed, previous studies have reported successful FBI of the calf station at 3 T. However, FBI of the thigh station at 3 T has been reported to suffer from signal void in the common femoral artery of 1 thigh only because of the radial symmetry in transmit radiofrequency field (B1+) variation. We sought to increase the signal of femoral artery in FBI at 3 T using high-permittivity dielectric padding. We performed FBI and B1+ mapping of the thigh station at 3 T in 13 human subjects to compare the following 3 dielectric padding settings: no padding, commercially available thick (approximately 5 cm) dielectric padding, and high-permittivity thin (approximately 2 cm) dielectric padding. We characterized the radial symmetry in B1+ variation as well as its impact on the FBI signal at baseline and how dielectric padding improves B1+ and FBI. We evaluated the quality of 3 FBI MRA acquisitions using quantitative (ie, contrast-to-noise ratio of femoral arteries) and qualitative (ie, conspicuity of femoral arteries) analyses. With the subjects positioned on the magnetic resonance table in feet-first, supine orientation, the radial symmetry in B1+ variation attenuates the signal in the right common femoral artery. The signal void can be improved partially with commercial padding and improved further with high-permittivity padding. Averaging the results over the 13 subjects, the mean B1+, contrast-to-noise ratio, and conspicuity scores for the right common femoral artery were significantly higher with high-permittivity padding than with commercial padding and baseline (P < 0.001). Our study shows that high-permittivity dielectric padding can be used to increase the signal of femoral artery in FBI at 3 T.

Arterial wave reflection and subclinical left ventricular systolic dysfunction.

PubMed

Russo, Cesare; Jin, Zhezhen; Takei, Yasuyoshi; Hasegawa, Takuya; Koshaka, Shun; Palmieri, Vittorio; Elkind, Mitchell Sv; Homma, Shunichi; Sacco, Ralph L; Di Tullio, Marco R

2011-03-01

Increased arterial wave reflection is a predictor of cardiovascular events and has been hypothesized to be a cofactor in the pathophysiology of heart failure. Whether increased wave reflection is inversely associated with left-ventricular (LV) systolic function in individuals without heart failure is not clear. Arterial wave reflection and LV systolic function were assessed in 301 participants from the Cardiovascular Abnormalities and Brain Lesions (CABL) study using two-dimensional echocardiography and applanation tonometry of the radial artery to derive central arterial waveform by a validated transfer function. Aortic augmentation index (AIx) and wasted energy index (WEi) were used as indices of wave reflection. LV systolic function was measured by LV ejection fraction (LVEF) and tissue Doppler imaging (TDI). Mitral annulus peak systolic velocity (Sm), peak longitudinal strain and strain rate were measured. Participants with history of coronary artery disease, atrial fibrillation, LVEF less than 50% or wall motion abnormalities were excluded. Mean age of the study population was 68.3 ± 10.2 years (64.1% women, 65% hypertensive). LV systolic function by TDI was lower with increasing wave reflection, whereas LVEF was not. In multivariate analysis, TDI parameters of LV longitudinal systolic function were significantly and inversely correlated to AIx and WEi (P values from 0.05 to 0.002). In a community cohort without heart failure and with normal LVEF, an increased arterial wave reflection was associated with subclinical reduction in LV systolic function assessed by novel TDI techniques. Further studies are needed to investigate the prognostic implications of this relationship.

The effect of vasodilatory medications on radial artery spasm in patients undergoing transradial coronary artery procedures: a systematic review.

PubMed

Curtis, Elizabeth; Fernandez, Ritin; Lee, Astin

2017-07-01

The uptake of percutaneous coronary procedures via the radial artery has increased internationally due to the decreased risk of complications and increased patient satisfaction. The increased susceptibility of the radial artery to spasm however presents a potential risk for procedural failure. Although most experts agree on the need for prophylactic medications to reduce radial artery spasm, currently there is inconsistency in literature regarding the most effective vasodilatory medication or combination of medications. The objective of this study is to identify the effectiveness of vasodilatory medications on radial artery spasm in patients undergoing transradial coronary artery procedures. This review considered studies that included participants aged 18 years and over undergoing non-emergent transradial percutaneous coronary artery procedures. This review considered studies that used vasodilating intravenous and intra-arterial medications or combinations of medications prior to commencing and during transradial coronary approaches to reduce radial artery spasm. The outcomes of interest were the incidence of radial artery spasm during percutaneous coronary procedure using objective and/or subjective measures and its effect on the successful completion of the procedure. Randomized controlled trials published in the English language between 1989 to date were considered for inclusion. The search strategy aimed to find both published and unpublished studies. A three-step search strategy was utilized in this review. An initial search of MEDLINE, CINAHL and Scopus was undertaken, followed by a search for unpublished studies. Papers selected for retrieval were assessed by two independent reviewers for methodological validity prior to inclusion in the review using standardized critical appraisal instruments. Any disagreements that arose between the reviewers were resolved through discussion. Quantitative data was extracted from papers included in the review using the standardized data extraction tool from RevMan5 (Copenhagen: The Nordic Cochrane Centre, Cochrane). Quantitative data, where possible, was pooled in statistical meta-analysis using RevMan5. All results were subject to double data entry. Effect sizes expressed as risk ratio (for categorical data) and weighted mean differences (for continuous data) and their 95% confidence intervals were calculated for analysis. Nine trials involving 3614 patients were included in the final review. Pooled data involving 992 patients on the effect of calcium channel blockers demonstrated a statistically significant reduction in the incidence of vasospasm in patients who received verapamil 5 mg compared to those who received a placebo (OR 0.33; 95%CI 0.19, 0.58). Similarly patients who received verapamil 2.5 mg or 1.25 mg had significantly fewer incidences of vasospasm when compared to those who received a placebo. Nitroglycerine 100mcg was demonstrated to be associated with a statistically significant reduction in the incidence of vasospasm. The evidence demonstrates a benefit in the use of vasodilatory medications for the reduction of vasospasm in patients having radial coronary procedures. Further large-scale multi-center trials are needed to determine the preferred medication.

A new radial strain and strain rate estimation method using autocorrelation for carotid artery

NASA Astrophysics Data System (ADS)

Ye, Jihui; Kim, Hoonmin; Park, Jongho; Yeo, Sunmi; Shim, Hwan; Lim, Hyungjoon; Yoo, Yangmo

2014-03-01

Atherosclerosis is a leading cause of cardiovascular disease. The early diagnosis of atherosclerosis is of clinical interest since it can prevent any adverse effects of atherosclerotic vascular diseases. In this paper, a new carotid artery radial strain estimation method based on autocorrelation is presented. In the proposed method, the strain is first estimated by the autocorrelation of two complex signals from the consecutive frames. Then, the angular phase from autocorrelation is converted to strain and strain rate and they are analyzed over time. In addition, a 2D strain image over region of interest in a carotid artery can be displayed. To evaluate the feasibility of the proposed radial strain estimation method, radiofrequency (RF) data of 408 frames in the carotid artery of a volunteer were acquired by a commercial ultrasound system equipped with a research package (V10, Samsung Medison, Korea) by using a L5-13IS linear array transducer. From in vivo carotid artery data, the mean strain estimate was -0.1372 while its minimum and maximum values were -2.961 and 0.909, respectively. Moreover, the overall strain estimates are highly correlated with the reconstructed M-mode trace. Similar results were obtained from the estimation of the strain rate change over time. These results indicate that the proposed carotid artery radial strain estimation method is useful for assessing the arterial wall's stiffness noninvasively without increasing the computational complexity.

Noninvasive Evaluation of Varying Pulse Pressures in vivo Using Brachial Sphymomanometry, Applanation Tonometry, and Pulse Wave Ultrasound Manometry.

PubMed

Li, Ronny X; Ip, Ada; Sanz-Miralles, Elena; Konofagou, Elisa E

2017-06-01

The routine assessment and monitoring of hypertension may benefit from the evaluation of arterial pulse pressure (PP) at more central locations (e.g. the aorta) rather solely at the brachial artery. Pulse Wave Ultrasound Manometry (PWUM) was previously developed by our group to provide direct, noninvasive aortic PP measurements using ultrasound elasticity imaging. Using PWUM, radial applanation tonometry, and brachial sphygmomanometry, this study investigated the feasibility of noninvasively obtaining direct PP measurements at multiple arterial locations in normotensive, pre-hypertensive, and hypertensive human subjects. Two-way ANOVA indicated a significantly higher aortic PP in the hypertensive subjects, while radial and brachial PP were not significantly different among the subject groups. No strong correlation (r 2 < 0.45) was observed between aortic and radial/brachial PP in normal and pre-hypertensive subjects, suggesting that increases in PP throughout the arterial tree may not be uniform in relatively compliant arteries. However, there was a relatively strong positive correlation between aortic PP and both radial and brachial PP in hypertensive subjects (r 2 = 0.68 and 0.87, respectively). PWUM provides a low-cost, non-invasive, and direct means of measuring the pulse pressure in large central arteries such as the aorta. When used in conjunction with peripheral measurement devices, PWUM allows for the routine screening of hypertension and monitoring of BP-lowering drugs based on the PP from multiple arterial sites.

Incidence and predictors of radial artery spasm during transradial coronary angiography and intervention.

PubMed

Jia, De-An; Zhou, Yu-Jie; Shi, Dong-Mei; Liu, Yu-Yang; Wang, Jian-Long; Liu, Xiao-Li; Wang, Zhi-Jian; Yang, Shi-Wei; Ge, Hai-Long; Hu, Bin; Yan, Zhen-Xian; Chen, Yi; Gao, Fei

2010-04-05

Radial artery spasm (RAS) is the most common complication in transradial coronary angiography and intervention. In this study, we designed to investigate the incidence of RAS during transradial procedures in Chinese, find out the independent predictors through multiple regression, and analyze the clinical effect of RAS during follow-up. Patients arranged to receive transradial coronary angiography and intervention were consecutively enrolled. The incidence of RAS was recorded. Univariate analysis was performed to find out the influence factors of RAS, and logistic regression analysis was performed to find out the independent predictors of RAS. The patients were asked to return 1 month later for the assessment of the radial access. The incidence of RAS was 7.8% (112/1427) in all the patients received transradial procedure. Univariate analysis indicates that young (P = 0.038), female (P = 0.026), small diameter of radial artery (P < 0.001), diabetes (P = 0.026), smoking (P = 0.019), moderate or severe pain during radial artery cannulation (P < 0.001), unsuccessful access at first attempt (P = 0.002), big sheath (P = 0.004), number of catheters (> 3) (P = 0.048), rapid baseline heart rate (P = 0.032) and long operation time (P = 0.021) were associated with RAS. Logistic regression showed that female (OR = 1.745, 95%CI: 1.148 - 3.846, P = 0.024), small radial artery diameter (OR = 4.028, 95%CI: 1.264 - 12.196, P = 0.008), diabetes (OR = 2.148, 95%CI: 1.579 - 7.458, P = 0.019) and unsuccessful access at first attempt (OR = 1.468, 95%CI: 1.212 - 2.591, P = 0.032) were independent predictors of RAS. Follow-up at (28 +/- 7) days after the procedure showed that, compared with non-spasm patients, the RAS patients had higher portion of pain (11.8% vs. 6.2%, P = 0.043). The occurrences of hematoma (7.3% vs. 5.6%, P = 0.518) and radial artery occlusion (3.6% vs. 2.6%, P = 0.534) were similar. The incidence of RAS during transradial coronary procedure was 7.8%. Logistic regression analysis showed that female, small radial artery diameter, diabetes and unsuccessful access at first attempt were the independent predictors of RAS.

Neurological Complications Comparing Endoscopically vs. Open Harvest of the Radial Artery

ClinicalTrials.gov

2016-07-05

Complications Due to Coronary Artery Bypass Graft; Coronary Artery Disease; Myocardial Ischemia; Coronary Disease; Heart Diseases; Cardiovascular Diseases; Arteriosclerosis; Arterial Occlusive Diseases; Vascular Diseases

Left Ventricular Function in Patients with Pulmonary Arterial Hypertension: The Role of Two-Dimensional Speckle Tracking Strain.

PubMed

de Amorim Corrêa, Ricardo; de Oliveira, Fernanda Brito; Barbosa, Marcia M; Barbosa, Jose Augusto A; Carvalho, Taís Soares; Barreto, Michele Campos; Campos, Frederico Thadeu A F; Nunes, Maria Carmo Pereira

2016-09-01

Pulmonary arterial hypertension (PAH) is characterized by elevated mean pulmonary arterial pressure with abnormal right ventricular (RV) pressure overload that may alter left ventricular (LV) function. The aim of this study was to assess the impact of RV pressure overload on LV function in PAH patients using two-dimensional (2D) speckle tracking strain. The study enrolled 37 group 1 PAH patients and 38 age- and gender-matched healthy controls. LV longitudinal and radial 2D strains were measured with and without including the ventricular septum. Six-minute walk test (6MWT) and brain natriuretic peptide (BNP) levels were also obtained in patients with PAH. The mean age of patients was 46.4 ± 14.8 years, 76% women, and 16 patients (43%) had schistosomiasis. Sixteen patients (43%) were in WHO class III or IV under specific treatment for PAH. The overall 6MWT distance was 441 meters, and the BNP levels were 80 pg/mL. Patients with PAH more commonly presented with LV diastolic dysfunction and impairment of RV function when compared to controls. LV global longitudinal and radial strains were lower in patients than in controls (-17.9 ± 2.8 vs. -20.5 ± 1.9; P < 0.001 and 30.8 ± 10.5 vs. 49.8 ± 15.4; P < 0.001, respectively). After excluding septal values, LV longitudinal and radial strains remained lower in patients than in controls. The independent factors associated with global LV longitudinal strain were LV ejection fraction, RV fractional area change, and tricuspid annular systolic motion. This study showed impaired LV contractility in patients with PAH assessed by speckle tracking strain, irrespective of ventricular septal involvement. Global LV longitudinal strain was associated independently with RV fractional area change and tricuspid annular systolic motion, after adjustment for LV ejection fraction. © 2016, Wiley Periodicals, Inc.

A review on fracture prevention of stent in femoropopliteal artery

NASA Astrophysics Data System (ADS)

Atan, Bainun Akmal Mohd; Ismail, Al Emran; Taib, Ishkrizat; Lazim, Zulfaqih

2017-01-01

Heavily calcific lesions, total occlusions, tortuous blood vessels, variable lengths of arteries, various dynamic loads and deformations in the femoropopliteal (FP) arterial segment make stenosis treatments are complicated. The dynamic forces in FP artery including bending, torsion and radial compression may lead to stent fracture (SF) and eventually to in-stent restenosis (ISR). Stent design specifically geometrical configurations are a major factor need to be improved to optimize stent expansion and flexibility both bending and torsion during stent deployment into the diseased FP artery. Previous studies discovered the influence of various stent geometrical designs resulted different structural behaviour. Optimizing stent design can improve stent performances: flexibility and radial strength to prevent SF in FP arterial segment

A novel compliance measurement in radial arteries using strain-gauge plethysmography.

PubMed

Liu, Shing-Hong; Tyan, Chu-Chang; Chang, Kang-Ming

2009-09-01

We propose a novel method for assessing the compliance of the radial artery by using a two-axis mechanism and a standard positioning procedure for detecting the optimal measuring site. A modified sensor was designed to simultaneously measure the arterial diameter change waveform (ADCW) and pressure pulse waveform with a strain gauge and piezoresistor. In the x-axis scanning, the sensor could be placed close to the middle of the radial artery when the ADCW reached the maximum amplitude. In the Z-axis scanning, the contact pressure was continuously increased for data measurement. Upon the deformation of the strain gauge following the change in the vascular cross-section, the ADCW was transferred to the change of the vascular radius. The loaded strain compliance of the radial artery (C(strain)) can be determined by dividing the dynamic changed radius by the pulse pressure. Twenty-three untreated, mild or moderate hypertensive patients aged 29-85 were compared with 14 normotensive patients aged 25-62. The maximum strain compliance between the two groups was significantly different (p < 0.005). Of the hypertensive patients, 14 were at risk of developing hyperlipidemia. There was a significant difference between this and the normotension group (p < 0.005).

Balloon-Assisted Tracking Use Reduces Radial Artery Access Failure in an Experienced Radial Center and is Feasible During Primary PCI for STEMI.

PubMed

Obaid, Daniel; Hailan, Ahmed; Chase, Alexander; Dorman, Stephen; Jenkins, Geraint; Raybould, Adrian; Ramsey, Mark; Thomas, Phillip; Smith, David; Ionescu, Adrian

2017-07-01

This prospective study assesses balloon-assisted tracking (BAT) in reducing radial access failure during percutaneous coronary intervention (PCI). Arterial spasm prevents PCI from the radial artery in a small percentage of cases. A total of 2223 consecutive patients undergoing PCI from the radial approach were analyzed. Radial access failure mode and requirement for crossover to femoral access during a 12-month run-in period were compared with the following 14-month period with routine BAT usage. During the 14-month study period, 1334 radial PCIs were attempted. Twenty-six patients switched to femoral at an early stage, while 76 encountered radial spasm and underwent successful BAT in 69 cases (91%), giving a total crossover rate to femoral of 33/1334 (2.5%). Utilizing BAT rather than a femoral puncture reduced our institution's radial-femoral crossover rate from 7.6% to 2.5% (P<.01), which is also significantly lower than the radial-femoral crossover rate in the 12 months before BAT implementation (6.1%; P<.01). Mean procedure times were similar for those requiring BAT compared with conventional radial access (51.3 ± 21.3 min vs 47.9 ± 23.7 min; P=.23), and those crossing straight to femoral (BAT not attempted) (60.7 ± 31.9 min; P=.10). Mean first device/balloon time for the BAT-assisted primary PCI cases (22.6 ± 9.4 min) was similar to cases that had radial difficulties and converted to femoral without attempting BAT (25.8 ± 13.4 min; P=.54). BAT allowed catheter passage despite radial spasm in 91% of cases, significantly reducing the institution's rate of femoral crossover. During radial spasm in primary PCI, using BAT did not delay reperfusion compared with femoral crossover.

Metabolic liver function measured in vivo by dynamic (18)F-FDGal PET/CT without arterial blood sampling.

PubMed

Horsager, Jacob; Munk, Ole Lajord; Sørensen, Michael

2015-01-01

Metabolic liver function can be measured by dynamic PET/CT with the radio-labelled galactose-analogue 2-[(18)F]fluoro-2-deoxy-D-galactose ((18)F-FDGal) in terms of hepatic systemic clearance of (18)F-FDGal (K, ml blood/ml liver tissue/min). The method requires arterial blood sampling from a radial artery (arterial input function), and the aim of this study was to develop a method for extracting an image-derived, non-invasive input function from a volume of interest (VOI). Dynamic (18)F-FDGal PET/CT data from 16 subjects without liver disease (healthy subjects) and 16 patients with liver cirrhosis were included in the study. Five different input VOIs were tested: four in the abdominal aorta and one in the left ventricle of the heart. Arterial input function from manual blood sampling was available for all subjects. K*-values were calculated using time-activity curves (TACs) from each VOI as input and compared to the K-value calculated using arterial blood samples as input. Each input VOI was tested on PET data reconstructed with and without resolution modelling. All five image-derived input VOIs yielded K*-values that correlated significantly with K calculated using arterial blood samples. Furthermore, TACs from two different VOIs yielded K*-values that did not statistically deviate from K calculated using arterial blood samples. A semicircle drawn in the posterior part of the abdominal aorta was the only VOI that was successful for both healthy subjects and patients as well as for PET data reconstructed with and without resolution modelling. Metabolic liver function using (18)F-FDGal PET/CT can be measured without arterial blood samples by using input data from a semicircle VOI drawn in the posterior part of the abdominal aorta.

Civilian traumatic vascular injuries of the upper extremity:report of the Iranian national trauma project.

PubMed

Rasouli, Mohammad R; Moini, Majid; Khaji, Ali

2009-12-01

The determination of the pattern of traumatic vascular injuries of the upper extremity in Iran was the aim of this study. Data of the Iranian national trauma project were used to identify patients with upper extremity vascular injuries. This project was conducted in 8 major cities from 2000-2004. A total of 113 cases with 130 vascular injuries were found, including 2 axillary, 18 brachial, and 69 radial and ulnar arteries. In 91 cases (81%), penetrating trauma was responsible. Associated nerve and/or upper extremity fractures were seen in 20% and 18% of cases, respectively. End-to-end anastomosis, interposition of saphenous graft, and ligation were used for the management of 44%, 28%, and 17%, respectively, of brachial artery injuries. Ulnar and radial artery injuries had been either ligated (n = 36; 52%) or sutured (n = 33; 48%). Median, ulnar, and radial nerve injuries, except for one, had all been sutured primarily. No patients needed fasciotomy. Amputation and mortality resulting from associated injuries occurred in 3 (2.6%) and 5 (4.4%) patients, respectively. This study revealed that stabbings are the most frequent causes of these injuries in Iran, in spite of the management of patients in level 3 trauma centers; the rate of amputation is acceptable. However, this study does not provide limb functions of the patients.

Flow-gated radial phase-contrast imaging in the presence of weak flow.

PubMed

Peng, Hsu-Hsia; Huang, Teng-Yi; Wang, Fu-Nien; Chung, Hsiao-Wen

2013-01-01

To implement a flow-gating method to acquire phase-contrast (PC) images of carotid arteries without use of an electrocardiography (ECG) signal to synchronize the acquisition of imaging data with pulsatile arterial flow. The flow-gating method was realized through radial scanning and sophisticated post-processing methods including downsampling, complex difference, and correlation analysis to improve the evaluation of flow-gating times in radial phase-contrast scans. Quantitatively comparable results (R = 0.92-0.96, n = 9) of flow-related parameters, including mean velocity, mean flow rate, and flow volume, with conventional ECG-gated imaging demonstrated that the proposed method is highly feasible. The radial flow-gating PC imaging method is applicable in carotid arteries. The proposed flow-gating method can potentially avoid the setting up of ECG-related equipment for brain imaging. This technique has potential use in patients with arrhythmia or weak ECG signals.

Effects of various factors on Doppler ultrasonographic measurements of radial and coccygeal arterial blood pressure in privately owned, conscious cats.

PubMed

Whittemore, Jacqueline C; Nystrom, Michael R; Mawby, Dianne I

2017-04-01

OBJECTIVE To assess the effects of age, body condition score (BCS), and muscle condition score (MCS) on radial and coccygeal systolic arterial blood pressure (SAP) in cats. DESIGN Prospective randomized trial. ANIMALS 66 privately owned cats enrolled between May and December 2010. PROCEDURES BCS and MCS of cats were assessed by 2 investigators; SAP was measured via Doppler ultrasonic flow detector, with cats positioned in right lateral or sternal recumbency for measurements at the radial or coccygeal artery, respectively, with order of site randomized. Associations among variables were assessed through correlation coefficients, partial correlation coefficients, and ANCOVA. RESULTS Interrater reliability for BCS and MCS assessment was high (correlation coefficients, 0.95 and 0.83, respectively). No significant effect was identified for order of SAP measurement sites. Coccygeal and radial SAP were positively correlated (ρ = 0.45). The median difference in coccygeal versus radial SAP was 19 mm Hg, but differences were not consistently positive or negative. Radial SAP was positively correlated with age (ρ = 0.48) and negatively correlated with MCS (ρ = -0.30). On the basis of the correlation analysis, the association between radial SAP and MCS reflected the confounding influence of age. Coccygeal SAP was not significantly correlated with age, BCS, or MCS. CONCLUSIONS AND CLINICAL RELEVANCE Use of the coccygeal artery is recommended to reduce the confounding effects of age and sarcopenia on Doppler ultrasonographic SAP measurements in cats. Additionally, monitoring for changes in MCS is recommended for cats undergoing serial SAP measurement.

Radiation exposure and contrast agent use related to radial versus femoral arterial access during percutaneous coronary intervention (PCI)-Results of the FERARI study.

PubMed

Becher, Tobias; Behnes, Michael; Ünsal, Melike; Baumann, Stefan; El-Battrawy, Ibrahim; Fastner, Christian; Kuschyk, Jürgen; Papavassiliu, Theano; Hoffmann, Ursula; Mashayekhi, Kambis; Borggrefe, Martin; Akin, Ibrahim

2016-12-01

Data regarding radiation exposure related to radial versus femoral arterial access in patients undergoing percutaneous coronary intervention (PCI) remain controversial. This study aims to evaluate patients enrolled in the FERARI study regarding radiation exposure, fluoroscopy time and contrast agent use. The Femoral Closure versus Radial Compression Devices Related to Percutaneous Coronary Interventions (FERARI) study evaluated prospectively 400 patients between February 2014 and May 2015 undergoing PCI either using the radial or femoral access. In these 400 patients, baseline characteristics, procedural data such as procedural duration, fluoroscopy time, dose-area product (DAP) as well as the amount of contrast agent used were documented and analyzed. Median fluoroscopy time was not significantly different in patients undergoing radial versus femoral access (12.2 vs. 9.8min, p=0.507). Furthermore, median DAP (54.5 vs. 52.0 Gycm2, p=0.826), procedural duration (46.0 vs. 45.0min, p=0.363) and contrast agent use (185.5 vs. 199.5ml, p=0.742) were also similar in radial and femoral PCI. There was no difference regarding median fluoroscopy time, procedural duration, radiation dose or contrast agent use between radial versus femoral arterial access in PCI. Copyright © 2016 Elsevier Inc. All rights reserved.

Arterial Access in Patients With De Novo Acute Coronary Syndrome Undergoing Coronary Angiography.

PubMed

Abdul Jabbar, Ali; Mufti, Omar; Sabol, Angeline; Markert, Ronald; White, Bryan; Broderick, George

2017-04-01

Bleeding is a major limitation of antithrombotic therapy among invasively managed patients with non-ST-segment elevation acute coronary syndromes (NSTE-ACSs). Randomized clinical trials have generally failed to favor either the femoral or the radial arterial approach for coronary angiography or intervention in NSTE-ACS. In 561 hospitalized patients with a new diagnosis of NSTE-ACS referred for coronary angiography, 364 and 197 patients underwent the femoral and the radial approach, respectively. Femoral and radial access did not differ in bleeding complications in the first 72 hours (8 of 364 or 2.2% vs 8 of 197 or 4.1%, P = .21), duration of hospitalization (4.67 ± 5.02 vs 4.51 ± 4.81, P = .28) nor in-hospital mortality (0.8% vs 0.5%, P = .67). Contrast volume was higher for femoral versus radial cases (204 ± 119 vs 168 ± 104, P < .001). In patients with de novo NSTE-ACS without prior cardiac bypass, radial and femoral arterial access did not differ in instances of bleeding within the first 72 hours postoperatively, length of hospital stay, or in-hospital mortality. Less contrast was used in radial cases, which may represent an advantage for patients with renal insufficiency.

Complete "in situ" avulsion of the radial artery complicating transradial coronary rotational atherectomy.

PubMed

Mouawad, Nicolas J; Capers, Quinn; Allen, Christopher; James, Iyore; Haurani, Mounir J

2015-01-01

Transradial percutaneous access (TR) is promoted because of increased patient comfort and convenience as well as a lower risk of access site and cardiac complications in the literature. Increased use of the TR purports a new set of possible complications for which the vascular surgeon must be capable to recognize and manage. A 48-year-old, devout Jehovah's Witness, woman with a history of coronary artery bypass surgery presented with a non-ST-segment elevation acute myocardial infarction. Pretransfer catheterization demonstrated a heavily calcified, 90% distal left main stenosis with an occluded left internal mammary artery graft to the left anterior descending coronary artery. To minimize the risk of bleeding requiring a blood transfusion, a coronary rotational atherectomy via a TR was performed. A nonhydrophilic, 7F sheath was used to accommodate the larger rotational atherectomy burr sizes. The coronary procedure was successful, but the sheath removal was complicated by significant resistance to pullback while the patient complained of severe pain. Post procedure she developed a hematoma with motor and neurological deficits of her hand. Emergent surgical exploration with fasciotomy was planned. The radial artery was explored and found to be redundant and pulseless, prompting proximal evaluation and revealing complete avulsion of the radial artery at its origin. An intraoperative arteriogram revealed that the brachial and ulnar arteries and interosseous branches were patent and filled the palmar arch and surgical ligation of the radial artery was conducted. Vascular surgeons need to be aware of potential complications related to TR which are likely to increase as this method is more widely disseminated. Copyright © 2015 Elsevier Inc. All rights reserved.

A Unique Branching Pattern of the Axillary Artery: A Case Report

PubMed Central

Bagoji, Ishwar B.; Hadimani, Gavishiddappa A.; Bannur, Balappa M.; Patil, B.G.; Bharatha, Ambadasu

2013-01-01

During routine dissection classes for under graduate students, we found a unique and unusual case regarding the anomalous branching in the third part of the axillary artery was terminated into subscapular arterial trunk, superficial brachial artery and deep brachial artery. The subscapular arterial trunk was origin of several important arteries as the circumflex scapular, thoracodorsal, posterior circumflex humeral, thoraco-acromial and lateral thoracic arteries. The deep brachial artery in the arm gave anterior circumflex humeral artery at the surgical neck of humerus, which terminated in the cubital fossa by dividing into radial and ulnar arteries. The superficial brachial artery gave two profunda brachii arteries, both of which passed through spiral groove, along with radial nerve and three muscular branches, to brachialis muscle. This variation is very rare. As per our knowledge, we did not find any literature which explained variations which were similar to this. The normal and abnormal anatomy of the axillary region has practical importance among vascular radiologists and surgeons and it should be known for making an accurate diagnostic interpretation. PMID:24551680

A unique branching pattern of the axillary artery: a case report.

PubMed

Bagoji, Ishwar B; Hadimani, Gavishiddappa A; Bannur, Balappa M; Patil, B G; Bharatha, Ambadasu

2013-12-01

During routine dissection classes for under graduate students, we found a unique and unusual case regarding the anomalous branching in the third part of the axillary artery was terminated into subscapular arterial trunk, superficial brachial artery and deep brachial artery. The subscapular arterial trunk was origin of several important arteries as the circumflex scapular, thoracodorsal, posterior circumflex humeral, thoraco-acromial and lateral thoracic arteries. The deep brachial artery in the arm gave anterior circumflex humeral artery at the surgical neck of humerus, which terminated in the cubital fossa by dividing into radial and ulnar arteries. The superficial brachial artery gave two profunda brachii arteries, both of which passed through spiral groove, along with radial nerve and three muscular branches, to brachialis muscle. This variation is very rare. As per our knowledge, we did not find any literature which explained variations which were similar to this. The normal and abnormal anatomy of the axillary region has practical importance among vascular radiologists and surgeons and it should be known for making an accurate diagnostic interpretation.

The Value of Elastic Modulus Index as a Novel Surrogate Marker for Cardiovascular Risk Stratification by Dimensional Speckle-Tracking Carotid Ultrasonography

PubMed Central

Yoon, Ji Hyun; Cho, In-Jeong; Sung, Ji Min; Lee, Jinyong; Ryoo, Hojin; Shim, Chi Young; Hong, Geu-Ru; Chung, Namsik

2016-01-01

Background Carotid intima media thickness (CIMT) and the presence of carotid plaque have been used for risk stratification of cardiovascular disease (CVD). To date, however, the association between multi-directional functional properties of carotid artery and CVD has not been fully elucidated. We sought to explore the multi-directional mechanics of the carotid artery in relation to cardiovascular risk. Methods Four hundred one patients who underwent carotid ultrasound were enrolled between January 2010 and April 2013. A high risk of CVD was defined as more than 20% of 10-year risk based on the Framingham risk score. Using a speckle-tracking technique, the longitudinal and radial movements were analyzed in the B-mode images. Peak longitudinal and radial displacements, strain and strain rate were also measured. Beta stiffness and elastic modulus index were calculated from the radial measurements. Results Of the overall sample, 13% (52) of patients comprised the high-risk group. In multivariate logistic regression, CIMT and elastic modulus index were independently associated with a high-risk of CVD {odds ratio (OR): 1.810 [95% confidence interval (CI) 1.249–2.622] and OR: 1.767 (95% CI: 1.177–2.652); p = 0.002, 0.006, respectively}. The combination of CIMT and elastic modulus index correlated with a high-risk of CVD more so than CIMT alone. Conclusion The elastic modulus index of the carotid artery might serve as a novel surrogate marker of high-risk CVD. Measurement of the multi-directional mechanics of the carotid artery using the speckle tracking technique has potential for providing further information over conventional B-mode ultrasound for stratification of CVD risk. PMID:27721952

Innovative Approach to Preparing Radial Artery Cocktails in Response to Manufacturer Shortages of Nitroglycerin and Verapamil

PubMed Central

Parbhoo, Rupal K.; Wetz, Karen; Tschampel, Marva; Pompili, Vincent; Schenko, Elena; Mavko, Lou

2014-01-01

Abstract Background: Transradial access has gained popularity over transfemoral access for cardiac catheterization, because of the decreased risk of bleeding, time to ambulation, and length of stay leading to improved patient satisfaction. One disadvantage of the radial artery approach is vasospasm, which can be prevented with the administration of verapamil and nitroglycerin in a pre- and postradial cocktail. Unfortunately, there have been manufacturer shortages for both of these medications. Methods: The utilization of radial artery cocktails and other nitroglycerin compounding practices were evaluated in response to cost containment and waste reduction initiatives and to medication shortages. Results: A modified process for supplying verapamil and nitroglycerin for the transradial approach via separate syringes enabled physicians to have quick access to the medications and to customize the cocktail based on the patient’s needs. This process also decreased costs and minimized wastage. The change in practice decreased waste from 44% for preradial cocktail syringes and 66% for postradial cocktail syringes to 8.7%. Discussion: This process for supplying the medications necessary to perform a radial artery catheterization and intracoronary nitroglycerin has allowed for conservation of commercial product supply. PMID:25477581

Pulsatile flow of non-Newtonian blood fluid inside stenosed arteries: Investigating the effects of viscoelastic and elastic walls, arteriosclerosis, and polycythemia diseases.

PubMed

Nejad, A Abbas; Talebi, Z; Cheraghali, D; Shahbani-Zahiri, A; Norouzi, M

2018-02-01

In this study, the interaction of pulsatile blood flow with the viscoelastic walls of the axisymmetric artery is numerically investigated for different severities of stenosis. The geometry of artery is modeled by an axisymmetric cylindrical tube with a symmetric stenosis in a two-dimensional case. The effects of stenosis severity on the axial velocity profile, pressure distribution, streamlines, wall shear stress, and wall radial displacement for the viscoelastic artery are also compared to the elastics artery. Furthermore, the effects of atherosclerosis and polycythemia diseases on the hemodynamics and the mechanical behavior of arterial walls are investigated. The pulsatile flow of non-Newtonian blood is simulated inside the viscoelastic artery using the COMSOL Multiphysics software (version 5) and by employing the fluid-structure interaction (FSI) method and the arbitrary Lagrangian-Eulerian (ALE) method. Moreover, finite element method (FEM) is used to solve the governing equations on the unstructured grids. For modeling the non-Newtonian blood fluid and the viscoelastic arterial wall, the modified Casson model, and generalized Maxwell model are used, respectively. According to the results, with stenosis severity increasing from 25% to 75% at the time of maximum volumetric flow rate, the maximum value of axial velocity and its gradient increase 7.9 and 19.6 times, and the maximum wall shear stress of viscoelastic wall increases 24.2 times in the constriction zone. With the progression of the atherosclerosis disease (fivefold growth of arterial elastic modulus), the wall radial displacement of viscoelastic arterial walls decreases nearly 40%. In this study, axial velocity profile, pressure distribution, streamlines, wall radial displacement, and wall shear stress were examined for different percentages of stenosis (25%, 50%, and 75%). The atherosclerosis disease was investigated by the fivefold growth of viscoelastic arterial elastic modulus and polycythemia disease was examined by the 21-fold increase in the yield stress of the blood fluid. Furthermore, the comparison of results between the elastic and viscoelastic arterial walls shows that the wall radial displacement for viscoelastic artery is lower than that for the elastic artery as much as 21.7% for the severe stenosis of 75%. Copyright © 2017 Elsevier B.V. All rights reserved.

Pulse transit time differential measurement by fiber Bragg grating pulse recorder.

PubMed

Umesh, Sharath; Padma, Srivani; Ambastha, Shikha; Kalegowda, Anand; Asokan, Sundarrajan

2015-05-01

The present study reports a noninvasive technique for the measurement of the pulse transit time differential (PTTD) from the pulse pressure waveforms obtained at the carotid artery and radial artery using fiber Bragg grating pulse recorders (FBGPR). PTTD is defined as the time difference between the arrivals of a pulse pressure waveform at the carotid and radial arterial sites. The PTTD is investigated as an indicator of variation in the systolic blood pressure. The results are validated against blood pressure variation obtained from a Mindray Patient Monitor. Furthermore, the pulse wave velocity computed from the obtained PTTD is compared with the pulse wave velocity obtained from the color Doppler ultrasound system and is found to be in good agreement. The major advantage of the PTTD measurement via FBGPRs is that the data acquisition system employed can simultaneously acquire pulse pressure waveforms from both FBGPRs placed at carotid and radial arterial sites with a single time scale, which eliminates time synchronization complexity.

Radial artery pulse waveform analysis based on curve fitting using discrete Fourier series.

PubMed

Jiang, Zhixing; Zhang, David; Lu, Guangming

2018-04-19

Radial artery pulse diagnosis has been playing an important role in traditional Chinese medicine (TCM). For its non-invasion and convenience, the pulse diagnosis has great significance in diseases analysis of modern medicine. The practitioners sense the pulse waveforms in patients' wrist to make diagnoses based on their non-objective personal experience. With the researches of pulse acquisition platforms and computerized analysis methods, the objective study on pulse diagnosis can help the TCM to keep up with the development of modern medicine. In this paper, we propose a new method to extract feature from pulse waveform based on discrete Fourier series (DFS). It regards the waveform as one kind of signal that consists of a series of sub-components represented by sine and cosine (SC) signals with different frequencies and amplitudes. After the pulse signals are collected and preprocessed, we fit the average waveform for each sample using discrete Fourier series by least squares. The feature vector is comprised by the coefficients of discrete Fourier series function. Compared with the fitting method using Gaussian mixture function, the fitting errors of proposed method are smaller, which indicate that our method can represent the original signal better. The classification performance of proposed feature is superior to the other features extracted from waveform, liking auto-regression model and Gaussian mixture model. The coefficients of optimized DFS function, who is used to fit the arterial pressure waveforms, can obtain better performance in modeling the waveforms and holds more potential information for distinguishing different psychological states. Copyright © 2018 Elsevier B.V. All rights reserved.

Polymyxin B-immobilized fiber column hemoperfusion removes endotoxin throughout a 24-hour treatment period.

PubMed

Mitaka, Chieko; Fujiwara, Naoto; Yamamoto, Mamoru; Toyofuku, Takahiro; Haraguchi, Go; Tomita, Makoto

2014-10-01

The purpose of this study was to evaluate the extent of endotoxin adsorption by polymyxin B-immobilized fiber column hemoperfusion (PMX) performed for a 24-hour treatment period in patients with septic shock. Nineteen patients with septic shock were retrospectively studied. The plasma endotoxin concentrations of blood drawn from the radial artery and from the outlet circuit of the PMX column were measured by kinetic turbidimetric limulus assay using an MT-358 Toxinometer (Wako Pure Chemical Industries, Ltd, Osaka, Japan) after 24 hours of PMX treatment. The endotoxin removal rate was defined by the following equation: ([radial artery endotoxin concentration - outlet circuit of PMX column endotoxin concentration]/radial artery endotoxin concentration) × 100%. The patients had a median Acute Physiology and Chronic Health Evaluation II score of 29 at intensive care unit admission and a 28-day mortality of 47%. Before the start of the PMX treatment, the median radial arterial plasma endotoxin concentration was 16.48 pg/mL. After 24 hours of PMX treatment, the median radial plasma endotoxin concentration had decreased to 1.857 pg/mL, and the concentration at the outlet circuit of the PMX column was further decreased to 0.779 pg/mL. The median endotoxin removal rate was 74.4%. These findings suggest that 24-hour PMX treatment was effective in removing endotoxin continuously throughout the entire treatment period. Copyright © 2014 Elsevier Inc. All rights reserved.

Foster replantation of fingertip using neighbouring digital artery in a young child.

PubMed

Xu, Jing-Hong; Gao, Zheng-Jun; Yao, Jing-Ming; Tan, Wei-Qiang; Dawreeawo, Javed

2010-06-01

Reconstruction of an amputated fingertip in a young child demands special techniques for success. We report a 2.5-year-old female patient with an amputated left index fingertip with the vascular defect being too severe to perform the usual replantation. Comparing several methods, we used the neighbouring digital artery as the feeding artery to perform foster replantation. Finally, the patient was satisfied with the appearance and function of her fingers. The clinical case, techniques, results are described and discussed. We consider it a useful technique, especially for those with a rather severe vascular defect. A 2.5-year-old girl suffered a crush amputation of the left index fingertip. Only the flexor tendon of the amputated fingertip was connected to the proximal finger tissue and the blood supply was completely lost (Figure 1). The distal amputated fingertip was fixed using Kirschner wire under general anaesthesia. Then, microsurgery operation was carried out immediately to replant this amputated fingertip. Both ulnar and radial digital arteries were avulsed, while the dorsal vein was intact and the digital nerve was also surviving. The integrity of blood vessels was too traumatised to connect to the proximal part. In the case of the distal part of the ulnar artery of the injured index finger, the blood supply was established by anastomosing the distal end of the amputated tip and the radial artery of the middle finger, which was the feeding artery (Figure 2). A 11/0 nylon suture was used. The dorsal vein and digital nerve were repaired by means of microsurgical anastomosis. The wound was covered with the dorsal skin of the middle finger and the palmar skin of the index finger to form a skin pedicle, and then, immobility of the two fingers was maintained to prevent avulsion. The index tip obtained good blood supply and survived completely (Figure 3). Detachment of the index and middle finger was performed after 3 weeks, and both of the fingers showed good blood supply (Figure 4). The appearance and function of the index and middle fingers were satisfactory 3 months postoperatively. Copyright 2009 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

Reducing the risk of fatal and disabling hypoglycaemia: a comparison of arterial blood sampling systems.

PubMed

Brennan, K A; Eapen, G; Turnbull, D

2010-04-01

In 2008, the National Patient Safety Agency (NPSA) published a report after 42 incidents and two deaths where glucose-containing flush solutions were attached to the arterial line. The molar concentration of 5% glucose is 277 mmol litre(-1). Only a tiny amount of sample contamination will lead to an artificially high glucose. As the NPSA sought a solution, a bench model was constructed to compare the performance of three open and three closed arterial line systems in limiting sample contamination. All arterial line systems were set up in a standard manner and pressurized to 300 mm Hg with 5% glucose used as the flush solution. This was connected to the 'radial artery' using an 18 G needle representing the radial cannula. The radial artery was simulated using a wide-bore extension set with 'blood' flow at 60 ml min(-1). Blood was simulated by the addition of red dye to Hartmann's solution. Increasing multiples of arterial line dead space were aspirated and discarded. Blood samples were then obtained and glucose concentration was measured. Significant glucose contamination (3 mmol litre(-1) +/-3.4) was detected in all open arterial line systems up to an aspiration volume of five times the dead space. No samples from the closed systems recorded glucose concentration >1 mmol litre(-1). Recommended minimal discard volumes are inadequate in the presence of glucose as the flush solution and can lead to high blood glucose readings, inappropriate insulin use, and iatrogenic neuroglycopaenia. Our study demonstrates that the closed-loop arterial sampling system could be the universal solution sought by the NPSA.

S-shaped versus conventional straight skin incision: Impact on primary functional maturation, stenosis and thrombosis of autogenous radiocephalic arteriovenous fistula: Impact of incision on maturation, stenosis & failure of RCAVF. Study design: Prospective observational comparative.

PubMed

Kordzadeh, Ali; Panayiotopolous, Yiannis

2017-10-01

The objective of this study is to test the null hypothesis that an S-shaped surgical incision versus conventional (straight) skin incision in the creation of autogenous radiocephalic arteriovenous fistulas (RCAVFs) have no impact on the primary end-point of primary functional maturation and secondary end points of stenosis and thrombosis. A prospective observational comparative consecutive study with intention-to-treat on individuals undergoing only radiocephalic arteriovenous fistula (RCAVFs) over a period of 12 months was conducted. Variables on patient's demographics, comorbidities, anesthesia type, mean arterial blood pressure, thrill, laterality, cephalic vein and radial artery diameter were collated. The test of probability was assessed through Chi-Square, Kaplan-Meier survival estimator and Log-Rank analysis. Total of n = 83 individuals with median age of 67 years (IQR, 20-89) and male predominance 83% during this period were subjected to RCAVF formation. Total of n = 45 patients in straight skin incision were compared to n = 38 individuals in S-shaped group. Despite equal prevalence of demographics, comorbidities, anesthesia type, mean arterial blood pressure (MAP), thrill, laterality, cephalic vein and radial artery diameter ( p  > 0.05) higher incidence of juxta-anastomotic stenosis was noted in the straight skin incision group ( p  = 0.029) in comparative and survival analysis (Log-Rank, p  = 0.036). The maturation of the entire cohort was 69% (S-shaped 76% vs. straight group 62%) (p > 0.05). The outcome of this study demonstrates that S-shaped surgical skin incision is associated with a lower incidence of stenosis in comparison to straight incision type in RCAVF formation.

The radial approach to the wrist with styloidectomy: A cadaver study.

PubMed

Lecoq, F-A; Sébilo, A; Bellemère, P

2017-09-01

The radial approach to the wrist is already used in several surgical techniques such as radial styloidectomy and Zaidemberg's vascularized radial graft. The aim of our work was to describe the surgical anatomy of that approach and to determine the acceptable limits of radial oblique styloidectomy that does not damage the anterior and posterior radiocarpal ligaments. This radial approach was performed on 11 cadaver specimens. The superficial branches of the radial nerve and the antebrachial cephalic vein were carefully located in the superficial plane. The radiocarpal articular capsule was opened longitudinally between the first and second compartments of the extensor tendons. We drew the oblique radial styloidectomy line at 3, 6 and 9mm from the apex of radial styloid process on the articular surface and then measured the width of ligaments theoretically taken away by the styloidectomy. An oblique radial styloidectomy of less than 6mm preserved the anterior and posterior radiocarpal ligaments. There was one case of radial artery damage while opening the joint capsule. The radial approach to the wrist as described in this work provided good access to the radial styloid process, the radioscaphoid joint and the proximal pole of the scaphoid, if the approach is done carefully to preserve the superficial branches of the radial nerve, the antebrachial cephalic vein and the radial artery. Radial styloidectomy can be performed up to 6mm from the apex without significantly damaging the radiocarpal ligaments, particularly the volar ones. Copyright © 2017 SFCM. Published by Elsevier Masson SAS. All rights reserved.

Cross-Sectional Associations of Flow Reversal, Vascular Function, and Arterial Stiffness in the Framingham Heart Study.

PubMed

Bretón-Romero, Rosa; Wang, Na; Palmisano, Joseph; Larson, Martin G; Vasan, Ramachandran S; Mitchell, Gary F; Benjamin, Emelia J; Vita, Joseph A; Hamburg, Naomi M

2016-12-01

Experimental studies link oscillatory flow accompanied by flow reversal to impaired endothelial cell function. The relation of flow reversal with vascular function and arterial stiffness remains incompletely defined. We measured brachial diastolic flow patterns along with vasodilator function in addition to tonometry-based central and peripheral arterial stiffness in 5708 participants (age 47±13 years, 53% women) in the Framingham Heart Study Offspring and Third Generation cohorts. Brachial artery diastolic flow reversal was present in 35% of the participants. In multivariable regression models, the presence of flow reversal was associated with lower flow-mediated dilation (3.9±0.2 versus 5.0±0.2%; P<0.0001) and reactive hyperemic flow velocity (50±0.99 versus 57±0.93 cm/s; P<0.0001). The presence of flow reversal (compared with absence) was associated with higher central aortic stiffness (carotid-femoral pulse wave velocity 9.3±0.1 versus 8.9±0.1 m/s), lower muscular artery stiffness (carotid-radial pulse wave velocity 9.6±0.1 versus 9.8±0.1 m/s), and higher forearm vascular resistance (5.32±0.03 versus 4.66±0.02 log dyne/s/cm 5 ; P<0.0001). The relations of diastolic flow velocity with flow-mediated dilation, aortic stiffness, and forearm vascular resistance were nonlinear, with a steeper decline in vascular function associated with increasing magnitude of flow reversal. In our large, community-based sample, brachial artery flow reversal was common and associated with impaired vasodilator function and higher aortic stiffness. Our findings are consistent with the concept that flow reversal may contribute to vascular dysfunction. © 2016 American Heart Association, Inc.

Successful flow reduction surgery for a ruptured true posterior communicating artery aneurysm caused by the common carotid artery ligation for epistaxis.

PubMed

Yamao, Yukihiro; Takahashi, Jun C; Satow, Tetsu; Iihara, Koji; Miyamoto, Susumu

2014-01-01

Carotid artery occlusion can lead to the development of rare true posterior communicating artery (PCoA) aneurysms because of hemodynamic stress on the PCoA. Surgical treatment of these lesions is challenging. The authors report a case of a true PCoA aneurysm that developed and ruptured 37 years after ligation of the ipsilateral common carotid artery for epistaxis. The lesion was successfully treated with clipping of the distal M1 segment of the middle cerebral artery (MCA) after the occipital artery-radial artery free graft-MCA bypass, which led to extreme reduction in collateral flow through the PCoA. A cortical branch, located just proximal to the obliteration site, functioned as a sufficient flow outlet. The aneurysm shrank, and the patient has been doing well without any symptoms for 5 years after surgery. M1 obliteration combined with high-flow extra-intracranial bypass might be a promising option for a true PCoA aneurysm, and therapeutic design that leaves a sufficient flow outlet on the M1 is mandatory to avoid unexpected occlusion of the M1 and its perforators.

Successful flow reduction surgery for a ruptured true posterior communicating artery aneurysm caused by the common carotid artery ligation for epistaxis

PubMed Central

Yamao, Yukihiro; Takahashi, Jun C.; Satow, Tetsu; Iihara, Koji; Miyamoto, Susumu

2014-01-01

Background: Carotid artery occlusion can lead to the development of rare true posterior communicating artery (PCoA) aneurysms because of hemodynamic stress on the PCoA. Surgical treatment of these lesions is challenging. Case Description: The authors report a case of a true PCoA aneurysm that developed and ruptured 37 years after ligation of the ipsilateral common carotid artery for epistaxis. The lesion was successfully treated with clipping of the distal M1 segment of the middle cerebral artery (MCA) after the occipital artery-radial artery free graft-MCA bypass, which led to extreme reduction in collateral flow through the PCoA. A cortical branch, located just proximal to the obliteration site, functioned as a sufficient flow outlet. The aneurysm shrank, and the patient has been doing well without any symptoms for 5 years after surgery. Conclusions: M1 obliteration combined with high-flow extra-intracranial bypass might be a promising option for a true PCoA aneurysm, and therapeutic design that leaves a sufficient flow outlet on the M1 is mandatory to avoid unexpected occlusion of the M1 and its perforators. PMID:25525556

Measurement of Blood Pressure Using an Arterial Pulsimeter Equipped with a Hall Device

PubMed Central

Lee, Sang-Suk; Nam, Dong-Hyun; Hong, You-Sik; Lee, Woo-Beom; Son, Il-Ho; Kim, Keun-Ho; Choi, Jong-Gu

2011-01-01

To measure precise blood pressure (BP) and pulse rate without using a cuff, we have developed an arterial pulsimeter consisting of a small, portable apparatus incorporating a Hall device. Regression analysis of the pulse wave measured during testing of the arterial pulsimeter was conducted using two equations of the BP algorithm. The estimated values of BP obtained by the cuffless arterial pulsimeter over 5 s were compared with values obtained using electronic or liquid mercury BP meters. The standard deviation between the estimated values and the measured values for systolic and diastolic BP were 8.3 and 4.9, respectively, which are close to the range of values of the BP International Standard. Detailed analysis of the pulse wave measured by the cuffless radial artery pulsimeter by detecting changes in the magnetic field can be used to develop a new diagnostic algorithm for BP, which can be applied to new medical apparatus such as the radial artery pulsimeter. PMID:22319381

A Generalized Maxwell Model for Creep Behavior of Artery Opening Angle

PubMed Central

Zhang, W.; Guo, X.; Kassab, G. S.

2009-01-01

An artery ring springs open into a sector after a radial cut. The opening angle characterizes the residual strain in the unloaded state, which is fundamental to understanding stress and strain in the vessel wall. A recent study revealed that the opening angle decreases with time if the artery is cut from the loaded state, while it increases if the cut is made from the no-load state due to viscoelasticity. In both cases, the opening angle approaches the same value in 3 hours. This implies that the characteristic relaxation time is about 10,000 sec. Here, the creep function of a generalized Maxwell model (a spring in series with six Voigt bodies) is used to predict the temporal change of opening angle in multiple time scales. It is demonstrated that the theoretical model captures the salient features of the experimental results. The proposed creep function may be extended to study the viscoelastic response of blood vessels under various loading conditions. PMID:19045526

Brachiomedian artery (arteria brachiomediana) revisited: a comprehensive review

PubMed Central

Kachlik, David; Konarik, Marek; Riedlova, Jitka; Baca, Vaclav

2016-01-01

This article reviews in detail the superficial brachiomedian artery (arteria brachiomediana superficialis), a very rare variant of the main arterial trunks of the upper limb. It branches either from the axillary artery or the brachial artery, descends superficially in the arm (similar to the course of the superficial brachial artery) and continues across the cubital fossa, runs superficially in the forearm, approaches the median nerve and enters the carpal canal to reach the hand. It usually terminates in the superficial palmar arch. The first drawing was published, in 1830, and the first description was published, in 1844. Altogether, to our knowledge, only 31 cases of a true, superficial brachiomedian artery have been reported (Some cases are incorrectly reported as superficial brachioradiomedian artery or superficial brachioulnomedian artery). Based on a meta-analysis of known, available studies, the incidence is 0.23% in Caucasians and 1.48% in Mongolians. Knowing whether or not this arterial variant is present is important in clinical medicine and relevant for: The catheterization via the radial or ulnar artery; harvesting the vascular pedicle for a forearm flap based on the radial, ulnar or superficial brachiomedian arteries; the possible collateral circulation in cases of the arterial closure; and the surgical management of carpal tunnel syndrome. Its presence can elevate the danger of an injury to the superficially located variant artery or of an accidental injection. PMID:27131025

Two cases of Bezold-Jarisch reflex induced by intra-arterial nitroglycerin in critical left main coronary artery stenosis.

PubMed

Shah, Sachin P; Waxman, Sergio

2013-01-01

The Bezold-Jarisch reflex, a well-described phenomenon, occurs upon the stimulation of intracardiac mechanoreceptors and is mediated by vagal afferent nerve fibers. Several factors can sensitize the cardiovascular system to develop this reflex, including acute myocardial ischemia, natriuretic peptides, and, rarely, nitroglycerin administration in the setting of acute myocardial infarction. The development of the Bezold-Jarisch reflex in the presence of severe coronary artery stenosis, specifically left main coronary artery stenosis, has not been described. We report 2 cases of patients who underwent elective coronary angiography and were given intra-arterial nitroglycerin during radial sheath insertion to reduce radial artery spasm. In both patients, bradycardia and hypotension developed along with diaphoresis, consistent with the Bezold-Jarisch reflex. Coronary angiography revealed critical (>90%) left main coronary artery stenosis in both patients. Critical left main coronary artery stenosis might sensitize mechanoreceptors or vagal afferents to the development of the Bezold-Jarisch reflex after intra-arterial nitroglycerin use; however, the mechanism of this possible relationship is unclear. In addition to discussing our patients' cases, we review the medical literature relevant to the Bezold-Jarisch reflex.

Prevalence of chronic kidney disease among patients undergoing transradial percutaneous coronary interventions.

PubMed

Hossain, Mohammad A; Quinlan, Amy; Heck-Kanellidis, Jennifer; Calderon, Dawn; Patel, Tejas; Gandhi, Bhavika; Patel, Shrinil; Hetavi, Mahida; Costanzo, Eric J; Cosentino, James; Patel, Chirag; Dewan, Asa; Kuo, Yen-Hong; Salman, Loay; Vachharajani, Tushar J

2018-07-01

While transradial approach to conduct percutaneous coronary interventions offers multiple advantages, the procedure can cause radial artery damage and occlusion. Because radial artery is the preferred site for the creation of an arteriovenous fistula to provide dialysis, patients with chronic kidney disease are particularly dependent on radial artery for their long-term survival. In this retrospective study, we investigated the prevalence of chronic kidney disease in patients undergoing coronary interventions via radial artery. Stage of chronic kidney disease was based on estimated glomerular filtration rate and National Kidney Foundation - Kidney Disease Outcomes Quality Initiative guidelines. A total of 497 patients undergoing transradial percutaneous coronary interventions were included. Over 70.4% (350/497) of the patients had chronic kidney disease. Stage II chronic kidney disease was observed in 243 (69%) patients (estimated glomerular filtration rate = 76.0 ± 8.4 mL/min). Stage III was observed in 93 (27%) patients (estimated glomerular filtration rate = 49 ± 7.5 mL/min). Stage IV chronic kidney disease was observed in 5 (1%) patients (estimated glomerular filtration rate = 25.6 ± 4.3 mL/min) and Stage V chronic kidney disease was observed in 9 (3%) patients (estimated glomerular filtration rate = 9.3 ± 3.5 mL/min). Overall, 107 of 350 patients (30%) had advanced chronic kidney disease, that is, stage III-V chronic kidney disease. Importantly, 14 of the 107 (13%) patients had either stage IV or V chronic kidney disease. This study finds that nearly one-third of the patients undergoing transradial percutaneous coronary interventions have advanced chronic kidney disease. Because many of these patients may require dialysis, the use of radial artery to conduct percutaneous coronary interventions must be carefully considered in chronic kidney disease population.

Triglycerides are a predictive factor for arterial stiffness: a community-based 4.8-year prospective study.

PubMed

Wang, Xiaona; Ye, Ping; Cao, Ruihua; Yang, Xu; Xiao, Wenkai; Zhang, Yun; Bai, Yongyi; Wu, Hongmei

2016-05-18

Epidemiological studies have disclosed an independent effect of triglycerides on coronary heart disease despite achievement of low-density lipoprotein cholesterol goals with statin therapy. Arterial stiffness has been increasingly recognized as a strong predictor of cardiovascular disease and atherosclerotic disease. The association between triglycerides and arterial stiffness is not well characterized. We aimed to determine the relationship between triglycerides and arterial stiffness in a community-based longitudinal sample from Beijing, China. We related levels of plasma TGs to measures of arterial stiffness (carotid-femoral pulse wave velocity [PWV] and carotid-radial PWV) in 1447 subjects (mean age, 61.3 years) from a community-based population in Beijing, China. After a median follow-up interval of 4.8 years, multiple linear regression analysis revealed that TGs were independently associated with carotid-femoral PWV (β = 0.747, P < 0.001) and carotid-radial PWV (β = 0.367, P = 0.001). In the group older than 65 years, the association between baseline TG levels and follow-up carotid-femoral PWV (β = 1.094, P = 0.001) and carotid-radial PWV (β = 0.524, P = 0.002) were strengthened. In forward stepwise multivariate logistic regression analysis, every SD increase in TGδ was associated with a 1.296-increased likelihood of the presence of carotid-femoral PWVδII (OR [per SD increase in TGδ]: 1.296; 95% CI: 1.064 ~ 1.580; P = 0.010) in Model 2, whereas the relationship between TGδ and carotid-radial PWVδII disappeared. In addition, the relationship was strengthened between TGδ and the presence of carotid-femoral PWVδII (OR 1.526, 95% CI: 1.088-2.141, P = 0.014) in the group older than 65 years but not carotid-radial PWVδII. No association was noted in subjects younger than 65 years. Lower triglyceride levels were significantly associated with decreases in carotid-femoral PWV, indicating that achieving low TG levels may be an additional therapeutic consideration in subjects with atherosclerotic disease.

Comparison of endothelial function of coronary artery bypass grafts in diabetic and nondiabetic patients: Which graft offers the best?

PubMed Central

Gür, Demet Özkaramanlı; Gür, Özcan; Gürkan, Selami; Cömez, Selcem; Gönültaş, Aylin; Yılmaz, Murat

2016-01-01

Objective: Diabetes associated endothelial dysfunction, which determines both long and short term graft patency, is not uniform in all coronary artery bypass surgery (CABG) grafts. Herein this study, we aimed to investigate the degree of endothelial dysfunction in diabetic radial artery (RA), internal mammarian artery (IMA) and saphenous vein (SV) grafts in vitro tissue bath system. Methods: This is a prospective experimental study. Fifteen diabetic and 15 non-diabetic patients were included to the study. A total number of 96 graft samples were collected; 16 graft samples for each graft type from both diabetic and non-diabetic patients. Arterial grafts were harvested with pedicles and SV grafts were harvested by ‘no touch’ technique. Vasodilatation response of vascular rings to carbachol, which induces nitric oxide (NO) mediated vasodilatation, was designated as the measure of endothelial function. Results: The IMA grafts had the most prominent NO mediated vasodilatation in both diabetic and non-diabetic patients, concluding a better preserved endothelial function than SV and RA. The ‘no-touch’ SV and RA grafts had similar vasodilatation responses in non-diabetic patients. In diabetic patients, on the other hand, RA grafts exhibited the least vasodilatation response (ie. worst endothelial function), even less vasodilatation than ‘no touch’ SV grafts (p<0.0001). Conclusion: Deteriorated function of RA grafts in diabetic patients, even worse than SV grafts made evident by this study, encourages the use of ‘no touch’ technique as the method of SV harvesting and more meticulous imaging of RA before its use as a graft in diabetic patients. PMID:26301347

Thrombosis of digital arteries associated with tamoxifen use: case report.

PubMed

Hutchison, Richard L; Rayan, Ghazi M

2012-02-01

Arterial thrombosis in the upper extremity occurs often at the wrist. We report a unique case of thrombosis that involved multiple digital arteries, without radial or ulnar artery involvement, which developed only after using tamoxifen despite chronic occupational blunt percussive hand use. Revascularization was achieved after thrombectomy. Multiple digital arterial thromboses may complicate the use of tamoxifen. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Arterial stiffness in 10-year-old children: current and early determinants.

PubMed

Schack-Nielsen, Lene; Mølgaard, Christian; Larsen, Dorthe; Martyn, Christopher; Michaelsen, Kim Fleischer

2005-12-01

It has been suggested that CVD has its origins in early life. An impairment of fetal growth and early postnatal nutrition may have programming effects on cardiovascular physiology. In addition, traditional risk factors for CVD may initiate the atherosclerotic process during childhood. We explored the effect of fat intake, physical activity and lipid profile in childhood, and birth weight, growth during infancy and breast-feeding on arterial stiffness in a cohort study of ninety-three 10-year-old children followed during infancy and re-examined at the age of 10 years. Arterial stiffness in two arterial segments (aorto-radial and aorto-femoral) was measured as pulse wave velocity. Arterial stiffness was inversely associated with physical activity (a regression coefficient in cm/s (95 % CI) of -6.8 (-11.2, -2.4) and -3.9 (-6.9, -0.8) per h of high physical activity/d in the aorto-radial and aorto-femoral segments, respectively). Arterial stiffness was also positively associated with dietary fat energy percentage (3.1 (95 % CI 0.9, 5.2) and 1.8 (95 % CI 0.2, 3.2) per fat energy percentage in the aorto-radial and aorto-femoral segments, respectively) but was not related to body composition, insulin resistance or lipid profile. Arterial stiffness was also positively associated with duration of breast-feeding for the aorto-femoral segment only (2.1 (95 % CI 0.4, 3.7) per month) but was not associated with growth in early life. In conclusion, patterns of physical activity and diet, and history of breast-feeding in infancy, have an influence on the stiffness of the large arteries in children. The long-term effects of this are unknown.

Impact of arterial access site on outcomes after primary percutaneous coronary intervention: prespecified subgroup analysis from the EUROMAX trial.

PubMed

Hamon, Martial; Coste, Pierre; Van't Hof, Arnoud; Ten Berg, Jurrien; Clemmensen, Peter; Tabone, Xavier; Benamer, Hakim; Kristensen, Steen D; Cavallini, Claudio; Marzocchi, Antonio; Hamm, Christian; Kanic, Vojko; Bernstein, Debra; Anthopoulos, Prodromos; Deliargyris, Efthymios N; Steg, Philippe Gabriel

2015-06-01

In European Ambulance Acute Coronary Syndrome Angiography (EUROMAX), bivalirudin improved 30-day clinical outcomes with reduced major bleeding compared with heparins plus optional glycoprotein IIb/IIIa inhibitors. We assessed whether choice of access site (radial or femoral) had an impact on 30-day outcomes and whether it interacted with the benefit of bivalirudin. In EUROMAX, choice of arterial access was left to operator discretion. Overall, 47% of patients underwent radial and 53% femoral access. Baseline risk was higher in the femoral access group. Unadjusted proportions for the primary outcome (death or noncoronary artery bypass graft protocol major bleeding at 30 days) were lower with radial access, however, without differences in major or major plus minor bleeding proportions. After multivariable adjustment, ischemic outcomes were no longer different between access site groups, except for a lower risk of stroke in radial patients. Bivalirudin was associated with lower proportions of the primary outcome in both the radial (odds ratio, 0.58; 95% CI, 0.33-1.03; P=0.058) and the femoral groups (odds ratio, 0.59; 95% CI, 0.37-0.93; P=0.022; interaction P=0.97). Bleeding was significantly lower in the bivalirudin group both in the radial- and femoral-treated patients but no significant difference was observed in ischemic outcomes. In multivariable analysis, bivalirudin emerged as the only independent predictor of reduced major bleeding (odds ratio, 0.45; 95% CI, 0.27-0.74; P=0.002). In this prespecified analysis from EUROMAX, radial access was preferred in lower risk patients and did not improve clinical outcomes. Bivalirudin was associated with less bleeding irrespective of access site. URL: http://www.clinicaltrials.gov. Unique identifier: NCT01087723. © 2015 American Heart Association, Inc.

Design and rationale of the AngioSeal versus the Radial approach In acute coronary SyndromE (ARISE) trial: a randomized comparison of a vascular closure device versus the radial approach to prevent vascular access site complications in non-ST-segment elevation acute coronary syndrome patients.

PubMed

de Andrade, Pedro Beraldo; E Mattos, Luiz Alberto Piva; Tebet, Marden André; Rinaldi, Fábio Salerno; Esteves, Vinícius Cardozo; Nogueira, Ederlon Ferreira; França, João Ítalo Dias; de Andrade, Mônica Vieira Athanazio; Barbosa, Robson Alves; Labrunie, André; Abizaid, Alexandre Antônio Cunha; Sousa, Amanda Guerra de Moraes Rego

2013-12-18

Arterial access is a major site of bleeding complications after invasive coronary procedures. Among strategies to decrease vascular complications, the radial approach is an established one. Vascular closure devices provide more comfort to patients and decrease hemostasis and need for bed rest. However, the inconsistency of data proving their safety limits their routine adoption as a strategy to prevent vascular complications, requiring evidence through adequately designed randomized trials. The aim of this study is to compare the radial versus femoral approach using a vascular closure device for the incidence of arterial puncture site vascular complications among non-ST-segment elevation acute coronary syndrome patients submitted to an early invasive strategy. ARISE is a national, multicenter, non-inferiority randomized clinical trial. Two hundred patients with non-ST-segment elevation acute coronary syndrome will be randomized to either radial or femoral access using a vascular closure device. The primary outcome is the occurrence of vascular complications at an arterial puncture site 30 days after the procedure, including major bleeding, retroperitoneal hematoma, compartment syndrome, hematoma ≥ 5 cm, pseudoaneurysm, arterio-venous fistula, infection, limb ischemia, arterial occlusion, adjacent nerve injury or the need for vascular surgical repair. Enrollment was initiated in September 2012, and until October 2013 91 patients were included. The inclusion phase is expected to last until the second half of 2014. The ARISE trial will help define the role of a vascular closure device as a bleeding avoidance strategy in patients with NSTEACS. ClinicalTrials.gov identifier: NCT01653587.

[Alterations in arterial compliance of dyslipidemic patients].

PubMed

Clara, Fernando Mario; Corral, Pablo; Blanco, Gustavo Hector; Scandurra, Adriana Graciela; Meschino, Gustavo Javier

2015-01-01

We studied the alteration on the distensibility of the arterial walls caused by dyslipidemia LDLc dependent, along the decades of life, by means of a study of the radial artery pulse wave. We made an analysis of the radial artery pulse wave records acquired by means a movement displacement sensor, placed on radial palpation area. We recruited 100 dyslipidemic men without other cardiovascular risk factors, between the 3rd and the 6th decade. We identified the reflected wave in the records and we computed the augmentation index in order to quantify its amplitude and position. This index is useful to assess the endothelial dysfunction. Besides, we defined a velocity coefficient as the ratio between the size of the individuals and the delay time between the peak of the systolic wave and the arrival of the reflected wave. Results were compared against those obtained in a group of 161 healthy volunteers. We found that dyslipidemic patients presented augmentation index values similar to controls until the fourth decade, increasing thereafter with significant differences only in the 6th decade. No significant differences were found in the velocity index in any of the ages studied. We conclude that alterations produced by dyslipidemia take decades to manifest, and they begin affecting the mechanism of vasodilation of distal arteries with highest proportion of smooth muscle, without altering the proximal conduit arteries with more elastin content. Copyright © 2013 Sociedad Española de Arteriosclerosis. Published by Elsevier España. All rights reserved.

Vasodilatory effect and endothelial integrity in papaverine- and milrinone-treated human radial arteries.

PubMed

Rudzinski, P; Wegrzyn, P; Lis, G J; Piatek, J; Konstanty-Kalandyk, J; Nosalski, R; Mikolajczyk, T; Jasinska, M; Pyka-Fosciak, G; Guzik, T; Litwin, J A; Korbut, R; Sadowski, J

2013-02-01

Prevention of the vasospasm is an important aspect of coronary artery bypass grafting (CABG) with the use of radial artery (RA) as the conduit. We compared the effect of two phosphodiesterase inhibitors papaverine and milrinone on vasodilation and endothelial integrity of human RA segments harvested from 20 CABG patients. Vasodilatory effect of the drugs were assessed by organ bath technique in RA rings precontracted with KCl and phenylephrine. Endothelial integrity was evaluated by CD34 immunofluorescence in frozen sections. Vasorelaxation induced by papaverine was significantly greater as compared to that induced by milrinone (90.47% ± 10.16% vs. 78.98% ± 19.56%, p<0.05). Similarly, pretreament with papaverine more strongly inhibited the contractile response of RA rings to KCl (6.0 ± 8.0 mN vs. 26.7 ± 21.5 mN, p<0.001). Papaverine was also superior to milrinone in the preservation of endothelial integrity (75.3% ± 12.9% vs. 51.8% ± 18.0%, p<0.02). In conclusion, papaverine seems to be more suitable than milrinone for prevention of vasospasm in radial artery conduits used for CABG.

Spectral indices of cardiovascular adaptations to short-term simulated microgravity exposure

NASA Technical Reports Server (NTRS)

Patwardhan, A. R.; Evans, J. M.; Berk, M.; Grande, K. J.; Charles, J. B.; Knapp, C. F.

1995-01-01

We investigated the effects of exposure to microgravity on the baseline autonomic balance in cardiovascular regulation using spectral analysis of cardiovascular variables measured during supine rest. Heart rate, arterial pressure, radial flow, thoracic fluid impedance and central venous pressure were recorded from nine volunteers before and after simulated microgravity, produced by 20 hours of 6 degrees head down bedrest plus furosemide. Spectral powers increased after simulated microgravity in the low frequency region (centered at about 0.03 Hz) in arterial pressure, heart rate and radial flow, and decreased in the respiratory frequency region (centered at about 0.25 Hz) in heart rate. Reduced heart rate power in the respiratory frequency region indicates reduced parasympathetic influence on the heart. A concurrent increase in the low frequency power in arterial pressure, heart rate, and radial flow indicates increased sympathetic influence. These results suggest that the baseline autonomic balance in cardiovascular regulation is shifted towards increased sympathetic and decreased parasympathetic influence after exposure to short-term simulated microgravity.

Considerations for SphygmoCor radial artery pulse wave analysis: side selection and peripheral arterial blood pressure calibration.

PubMed

Martin, Jeffrey S; Borges, Alexandra R; Christy, John B; Beck, Darren T

2015-10-01

Methods employed for pulse wave analysis (PWA) and peripheral blood pressure (PBP) calibration vary. The purpose of this study was to evaluate the agreement of SphygmoCor PWA parameters derived from radial artery tonometry when considering (1) timing (before vs. after tonometry) and side selection (ipsilateral vs. contralateral limb) for PBP calibration and (2) side selection for tonometry (left vs. right arm). In 34 subjects (aged 21.9 ± 2.3 years), bilateral radial artery tonometry was performed simultaneously on three instances. PBP assessment via oscillometric sphygmomanometry in the left arm only and both arms simultaneously occurred following the first and second instances of tonometry, respectively. Significant within arm differences in PWA parameters derived before and after PBP measurement were observed in the right arm only (for example, aortic systolic blood pressure, Δ=0.38 ± 0.64 mm Hg). Simultaneously captured bilateral PWA variables demonstrated significant between arm differences in 88% (14/16) and 56% (9/16) of outcome variables when calibrated to within arm and equivalent PBP, respectively. Moreover, the right arm consistently demonstrated lower values for clinical PWA variables (for example, augmentation index, bias=-2.79%). However, 26% (n=9) of participants presented with clinically significant differences (>10 mm Hg) in bilateral PBP and their exclusion from analysis abolished most between arm differences observed. SphygmoCor PWA in the right radial artery results in greater variability independent of the timing of PBP measurement and magnitude of calibration pressures in young subjects. Moreover, bilateral PBP measurement is imperative to identify subjects in whom a significant difference in bilateral PWA outcomes may exist.

A comparison of the efficacy of heparinized and nonheparinized solutions for maintenance of perioperative radial arterial catheter patency and subsequent occlusion.

PubMed

Tuncali, Binnur E; Kuvaki, Buhar; Tuncali, Bahattin; Capar, Emine

2005-04-01

In a randomized, double-blind, controlled study, we compared heparinized and nonheparinized infusions for the maintenance of perioperative arterial catheter patency and the incidence of subsequent radial arterial occlusion. Two-hundred patients were randomized into 2 groups to receive heparinized (group H, n = 100) or nonheparinized (group S, n = 100) flush solutions. Radial and ulnar blood flows were assessed using Doppler probe and pulse oximetry before, just after, and 24 h after decannulation by the same investigator. The cannulation site was examined for complications such as hematoma, nerve injury, and infection. The mean duration of cannulations was 378 +/- 159.0 min in group H and 332 +/- 154.6 min in group S. The mean number of corrective interventions caused by dampening of the pressure wave (mean number of positional changes [group S, 1.5 +/- 2.0; group H, 1.4 +/- 3.8] and mean number of manual flushes [group S, 1.3 +/- 1.7; group H, 1.2 +/- 1.2]) was not significantly different in both groups. After decannulation, partial or total occlusion developed in 20 group H patients and 16 group S patients (not significant). The incidence of occlusion was correlated to the presence of hematoma at the puncture site after decannulation (P = 0.013), long duration of cannulation (P = 0.04), and age <65 yr (P = 0.009). In conclusion, there is no significant difference between heparinized and nonheparinized flush solutions for the maintenance of perioperative radial artery catheter patency.

Reverse radial artery flap for soft tissue defects of hand in pediatric age group.

PubMed

Cheema, Saeed Ashraf; Talaat, Nabeela

2009-01-01

To highlight the usefulness of reverse radial artery flap in covering various soft tissue defects of hand in paediatric age group. A total of 16 reverse radial artery flaps were utilized in a period of three years to cover various soft tissue defects of hand for paediatric age group patients. The age ranged from 5-18 years. The two common causes of soft tissue defects in this series were mechanical trauma and fireworks trauma with five cases in each group. Three of the cases were burn victims and other two presented with earth quake injuries. One patient had wound because of road traffic accident. Soft tissue defects of palm were covered with this flap in eight cases while in three cases it was wrapped around the thumb. First web space defects were covered with this flap in two cases. Two cases required coverage of amputation stump at transmetacarpal level and yet another required a big flap to cover the soft tissue defects at palm, dorsum and thumb. Donor site was covered with split skin graft in all cases but one, which was closed primarily. We had partial loss of flap in one case. Grafted donor sites healed uneventfully and were quite acceptable to the patients in due course of time. Reverse radial artery flap has a quite long arc of rotation which brings it great ease to cover the soft tissue defects of various areas of hand like palm, dorsum, first web space and thumb.

The non-contact measure of the heart rate variability by laser Doppler vibrometry: comparison with electrocardiography

NASA Astrophysics Data System (ADS)

Cosoli, G.; Casacanditella, L.; Tomasini, E. P.; Scalise, L.

2016-06-01

The assessment of the heart rate variability (HRV) is of utmost importance, being one of the most promising markers of the activity of the autonomic nervous system and associated to cardiovascular mortality. Different signals can be used to perform HRV, primarily electrocardiography (ECG), photoplethysmography (PPG), phonocardiography (PCG) or vibrocardiography (VCG), since the fundamental aspect is the individuation of a periodic feature strictly correlated with cardiac activity (i.e. R-peak in ECG or the first sound in PCG). In this work, the authors demonstrate that the VCG performances in HRV analysis are sufficiently accurate if compared to the ones measured by ECG (i.e. standard methodology); moreover, the authors want to prove the feasibility of such measurement in correspondence of different measurement points (i.e. carotid artery—which is the typical VCG measurement point—and the radial artery on the wrist)1. Results show that VCG has a mean deviation of  <1 bpm with respect to ECG in heart rate (HR) measurement; carotid artery is the most accurate site for the assessment, but also the radial artery is a valid site, even if with a reduced SNR. With regards to HRV parameters, the mean percentage deviation is  <10% in correspondence of carotid artery, and  ≈16% for the radial artery. So, VCG allows for non-contact monitoring of the cardiac activity.

Modified radial v/s biatrial maze for atrial fibrillation in rheumatic valvular heart surgery.

PubMed

Sayed, Sajid A; Katewa, Ashish; Srivastava, Vivek; Jana, Sujit; Patwardhan, Anil M

2014-01-01

Atrial fibrillation (AF) is commonest sustained atrial arrhythmia producing high morbidity. Although Cox's Maze III procedure cures AF in majority, reduced atrial transport function (ATF) is a concern. Radial approach with ablation lines radial from sinus node towards atrioventricular annulii and parallel to atrial coronary arteries, has shown better ATF. Single blind open randomized prospective study of 80 patients was undertaken in two groups (40 each) of modified Cox's maze III and modified radial approach, to evaluate conversion to normal sinus rhythm (NSR) and ATF. Patients undergoing surgery for rheumatic valvular heart disease with continuous AF were prospectively randomized. Ablation lines were created with radiofrequency (RF) bipolar coagulation with cryoablation for the isthmal lesions and coronary sinus. Results were compared at 6 months and ATF was evaluated by atrial filling fraction (AFF) and A/E ratio on echocardiography. The rate of conversion to NSR in both groups was statistically insignificant by Fisher's exact test (p > 0.05). ATF was better in modified radial approach compared to modified Cox's Maze III (A/E compared by unpaired t test:0.52 ± 0.08 v/s 0.36 ± 0.10; p < 0.05. AFF compared using Mann Whitney U test: median AFF for radial group was 23 v/s 20 for biatrial group; p < 0.05). In patients with AF undergoing rheumatic valvular surgery, radiofrequency radial approach is as effective as modified Cox's maze III for conversion to NSR with better atrial transport function. Copyright © 2014 Cardiological Society of India. Published by Elsevier B.V. All rights reserved.

The cholinomimetic agent carbachol induces headache in healthy subjects.

PubMed

Schytz, H W; Wienecke, T; Oturai, P S; Olesen, J; Ashina, M

2009-02-01

The parasympathetic nervous system is likely to be involved in migraine pathogenesis. We hypothesized that the cholinomimetic agonist carbachol would induce headache and vasodilation of cephalic and radial arteries. Carbachol (3 microg/kg) or placebo was randomly infused into 12 healthy subjects in a double-blind crossover study. Headache was scored on a verbal rating scale from 0-10. Velocity in the middle cerebral artery (V(MCA)) and diameter of the superficial temporal artery (STA) and radial artery (RA) were recorded. Nine participants developed headache after carbachol compared with three after placebo. The area under the curve for headache was increased after carbachol compared with placebo both during infusion (0-30 min) (P = 0.042) and in the postinfusion period (30-90 min) (P = 0.027). Carbachol infusion caused a drop in V(MCA) (P = 0.003) and an increase in STA diameter (P = 0.006), but no increase in the RA diameter (P = 0.200). In conclusion, the study demonstrated that carbachol caused headache and dilation of cephalic arteries in healthy subjects.

An Unusual Log-splitter Injury Leading to Radial Artery Thrombosis, Ulnar Artery Laceration, and Scapholunate Dissociation

PubMed Central

Spock, Christopher R.; Salomon, Jeffrey C.; Narayan, Deepak

2008-01-01

A log splitter is a gasoline- or diesel-powered machine that uses a hydraulic-powered cutting wedge to do the work of an axe. Log-splitter injuries that do not result in amputation of digits or limbs are uncommon and not well described in the literature. We present a unique case of a patient who sustained a log-splitter injury that resulted in thrombosis of the radial artery and avulsion laceration of the ulnar artery leading to acute hand ischemia, in addition to scapholunate ligament disruption leading to a DISI deformity. In this case, thrombolytic therapy was contraindicated and surgical revascularization was the best possible treatment option. Our case illustrates the pitfalls of using this modality in a crush injury, since the use of thrombolytics in this instance would have resulted in severe hemorrhage. An important clinical caveat is the potentially misleading arteriographic diagnosis of thrombosis and/or spasm. PMID:18827886

The anatomical relationship between the axillary artery and vein investigated by radial coronary angiography.

PubMed

Sert, Sena; Kepez, Alper; Atas, Halil; Mutlu, Bulent; Erdogan, Okan

2018-06-01

To reduce the risk of inadvertent arterial puncture and bleeding, we aimed to define a safe puncture site by demonstrating the relation of the axillary artery and vein. The anatomical course and relation as well as crossover sites of the axillary artery and vein, the presence of small arterial bridges over the axillary vein, and validation of commonly preferred axillary venous puncture sites were determined by simultaneous ipsilateral venography in patients (n  =  111; 80 men, age 60 ± 10 years) who underwent coronary angiography by radial artery access. The axillary vein was detected at the first costa-clavicular intersection in 62% and at the second anterior and third posterior costal intersection in 60% of the patients. Small arterial bridges over the axillary vein were observed in 77% of the patients and more frequently in females and body mass index ≥25 kg/m 2 (P  =  0.034 and P  =  0.03, respectively). The axillary artery crossed the vein in 24% of the patients and almost always within the region close to the first costa-clavicular intersection site. Our study demonstrated a high crossover rate (24%) of axillary artery and vein and a high degree of variation in the course of axillary vein. Small arterial bridges over the axillary vein were observed in 77% of the patients. © 2018 Wiley Periodicals, Inc.

Effects of blood pressure and sex on the change of wave reflection: evidence from Gaussian fitting method for radial artery pressure waveform.

PubMed

Liu, Chengyu; Zhao, Lina; Liu, Changchun

2014-01-01

An early return of the reflected component in the arterial pulse has been recognized as an important indicator of cardiovascular risk. This study aimed to determine the effects of blood pressure and sex factor on the change of wave reflection using Gaussian fitting method. One hundred and ninety subjects were enrolled. They were classified into four blood pressure categories based on the systolic blood pressures (i.e., ≤ 110, 111-120, 121-130 and ≥ 131 mmHg). Each blood pressure category was also stratified for sex factor. Electrocardiogram (ECG) and radial artery pressure waveforms (RAPW) signals were recorded for each subject. Ten consecutive pulse episodes from the RAPW signal were extracted and normalized. Each normalized pulse episode was fitted by three Gaussian functions. Both the peak position and peak height of the first and second Gaussian functions, as well as the peak position interval and peak height ratio, were used as the evaluation indices of wave reflection. Two-way ANOVA results showed that with the increased blood pressure, the peak position of the second Gaussian significantly shorten (P < 0.01), the peak height of the first Gaussian significantly decreased (P < 0.01) and the peak height of the second Gaussian significantly increased (P < 0.01), inducing the significantly decreased peak position interval and significantly increased peak height ratio (both P < 0.01). Sex factor had no significant effect on all evaluation indices (all P > 0.05). Moreover, the interaction between sex and blood pressure factors also had no significant effect on all evaluation indices (all P > 0.05). These results showed that blood pressure has significant effect on the change of wave reflection when using the recently developed Gaussian fitting method, whereas sex has no significant effect. The results also suggested that the Gaussian fitting method could be used as a new approach for assessing the arterial wave reflection.

[APPLICATION OF WRIST CREASE ISLAND FLAP BASED ON THE SUPERFICIAL PALMAR BRANCH OF THE RADIAL ARTERY FOR THUMB RECONSTRUCTION].

PubMed

Zheng Dawei; Li, Zhangcan; Xu, Li; Zhang, Xuyang; Shi, Rongjian; Sun, Feng; Shou, Kuishui

2015-04-01

To investigate the effectiveness of the island flaps based on the superficial palmar branch of the radial artery (SPBRA) to repair the thumb wound. Between February 2012 and November 2013, 8 cases of thumb defects and bilateral artery defect were treated. There were 5 males and 3 females with an average age of 30.5 years (range, 19-51 years). The injury was caused by crush (4 cases), avulsion (3 cases), and twist (1 case). The injury located at the metacarpophalangeal joints in 3 cases, at the proximal palmar side in 2 cases, and at the interphalangeal joints in 3 cases. The defect size ranged from 3.5 cm x 1.5 cm to 6.5 cm x 2.0 cm. The digital artery defect was 2.5-8.5 cm (mean, 5.3 cm). The disease duration was 2.0-4.5 hours (mean, 3.2 hours). The reversed island flaps based on the SPBRA were designed, which size was 4.0 cm x 2.0 cm to 7.5 cm x 3.0 cm. The donor sites were closed directly. The operation was successfully completed in 7 patients except 1 patient having vascular variation. All flaps survived completely. Wound and incision at the donor site healed by first intention. All patients were followed up 6-18 months (mean, 13 months). The flaps had similar color and texture to adjacent skin. Linear scar was seen at the donor site in 1 patient, with no functional limitation. According to the functional assessment criteria of upper limb by the Hand Surgery Branch of Chinese Medical Association, the results were excellent in 6 cases, good in 1 case, and fair in 1 case, with an excellent and good rate of 87.5%. The reversed island flap based on the SPBRA is an ideal flap for the thumb reconstruction because the advantages of reliable blood supply, easy dissection, less injury at donor site, and good repair results.

Subclavian steal: Endovascular treatment of total occlusions of the subclavian artery using a retrograde transradial subintimal approach

PubMed Central

Golwala, Sohil N; Vance, Ansar Z; Tuerff, Sonya N

2016-01-01

Introduction In symptomatic subclavian steal syndrome, endovascular treatment is the first line of therapy prior to extra-anatomic surgical bypass procedures. Subintimal recanalization has been well described in the literature for the coronary arteries, and more recently, in the lower extremities. By modifying this approach, we present a unique retrograde technique using a heavy tip microwire to perform controlled subintimal dissection. Methods We present two cases of symptomatic subclavian steal related to chronic total occlusion of the left subclavian artery and right innominate artery, respectively. Standard crossing techniques were unsuccessful. Commonly at this point, the procedures would be aborted and open surgical intervention would have to be pursued. In our cases, retrograde access was easily achieved via an ipsilateral retrograde radial artery, using controlled subintimal dissection and a heavy-tipped wire. Results We were able to easily achieve recanalization in both attempted cases of chronic total occlusion of the subclavian and innominate artery, using a retrograde radial subintimal approach. Subsequent stent-supported angioplasty resulted in complete revascularization. No major complications were encountered during the procedures; however, one patient did develop thromboembolic stroke secondary to platelet aggregation to the stent graft, 9 days post-procedure. Conclusions Endovascular treatment is considered the first-line intervention in medically refractory patients with symptomatic subclavian steal syndrome. In the setting of chronic total occlusions, a retrograde radial subintimal approach using a heavy tip wire for controlled subintimal dissection is a novel technique that may be considered when standard approaches and wires have failed. PMID:26861024

Ultrahigh-resolution ultrasound characterization of access site trauma and intimal hyperplasia following use of a 7F sheathless guide versus 6F sheath/guide combination for transradial artery PCI: Results of the PRAGMATIC trial.

PubMed

Batchelor, Wayne; Dahya, Vishal; McGee, Dan; Katopodis, John; Dixon, William; Campbell, James; Meredith, Ashley; Knap, Patty; Parkin, Mathew; Noel, Thomas

2018-04-01

There exist limited data on the relative degree of acute injury and late healing of the radial artery after transradial artery (TRA) percutaneous coronary intervention (PCI) with a 7F sheathless guide catheter compared with a 6F sheath/guide combination. We used ultrahigh-resolution (55 MHz) vascular ultrasound to compare intimal-medial thickening (IMT) and early and late radial artery (RA) injury resulting from a sheathless 7F guide catheter versus a 6F sheath/guide combination for TRA-PCI. Forty-one consecutive consenting patients undergoing elective nonemergent TRA-PCI at a single institution from June 2016 to December 2016 were included. Patients were randomized (stratified by sex) to undergo TRA-PCI using a 7F sheathless guide catheter versus a 6F sheath/6F guide combination. Ultrahigh-resolution vascular ultrasound (55MHz) of the RA access site was performed at 24hours and 90days post-TRA-PCI. The primary outcome of the study was a noninferiority comparison of radial artery IMT thickness at 90days. PCI success rates, fluoroscopy times, number of guides used, and crossover rates to a femoral approach were also compared. Baseline characteristics were similar between groups. Radial arterial IMT (mm) was similar between the 7F sheathless and 6F sheath/guide groups at 24hours (0.27 vs 0.29, respectively; P=.43) and at 90days (0.35 vs 0.34, respectively; P=.96). The P value for the noninferiority testing of a 0.07-mm limit was .002. Limited access site intimal tears were relatively common in both groups at 24hours (4 vs 5, P=.53) but often healed by 90days. Radial artery occlusion was infrequent at 90days (2 vs 1, P=.10), and no frank dissections were noted. PCI success rates (100% vs 95%, P=.59), fluoroscopy times (16 vs 12minutes, P=.17), number of guides used (1.1 vs 1.2, P=.48), and femoral crossover rates (0% vs 0%) were similar between the 2 respective groups. A 7F sheathless approach to TRA-PCI results in no more IMT and early or late RA trauma than a standard 6F sheath/guide combination, rendering the 7F sheathless technique an attractive option for complex TRA-PCI. Copyright © 2017 Elsevier Inc. All rights reserved.

A Novel Laboratory Approach for the Demonstration of Hemodynamic Principles: The Arterial Blood Flow Reflection

ERIC Educational Resources Information Center

Djelic, Marina; Mazic, Sanja; Zikic, Dejan

2013-01-01

In the frame of a laboratory training course for medicine students, a new approach for laboratory exercises has been applied to teach the phenomena of circulation. The exercise program included measurements of radial artery blood flow waveform for different age groups using a noninvasive optical sensor. Arterial wave reflection was identified by…

Identifying factors that predict the choice and success rate of radial artery catheterisation in contemporary real world cardiology practice: a sub-analysis of the PREVAIL study data.

PubMed

Pristipino, Christian; Roncella, Adriana; Trani, Carlo; Nazzaro, Marco S; Berni, Andrea; Di Sciascio, Germano; Sciahbasi, Alessandro; Musarò, Salvatore Donato; Mazzarotto, Pietro; Gioffrè, Gaetano; Speciale, Giulio

2010-06-01

To assess: the reasons behind an operator choosing to perform radial artery catheterisation (RAC) as against femoral arterial catheterisation, and to explore why RAC may fail in the real world. A pre-determined analysis of PREVAIL study database was performed. Relevant data were collected in a prospective, observational survey of 1,052 consecutive patients undergoing invasive cardiovascular procedures at nine Italian hospitals over a one month observation period. By multivariate analysis, the independent predictors of RAC choice were having the procedure performed: (1) at a high procedural volume centre; and (2) by an operator who performs a high volume of radial procedures; clinical variables played no statistically significant role. RAC failure was predicted independently by (1) a lower operator propensity to use RAC; and (2) the presence of obstructive peripheral artery disease. A 10-fold lower rate of RAC failure was observed among operators who perform RAC for > 85% of their personal caseload than among those who use RAC < 25% of the time (3.8% vs. 33.0%, respectively); by receiver operator characteristic (ROC) analysis, no threshold value for operator RAC volume predicted RAC failure. A routine RAC in all-comers is superior to a selective strategy in terms of feasibility and success rate.

Predictors of radio-cephalic arteriovenous fistulae patency in an Asian population.

PubMed

Joseph Lo, Zhiwen; Tay, Wee Ming; Lee, Qinyi; Chua, Jia Long; Tan, Glenn Wei Leong; Chandrasekar, Sadhana; Narayanan, Sriram

2016-09-21

To identify predictors of arteriovenous fistula (AVF) patency in Asian patients with autogenous radio-cephalic arteriovenous fistula (RCAVF). Retrospective review of 436 RCAVFs created between 2009 and 2013. Predictors of patency were identified with univariate and multivariate analysis. Kaplan-Meier survival analysis and log-rank test were used to calculate patency rates. Overall secondary patency rate was 72% at 12 months, 69% at 24 months, 58% at 36 months, 57% at 48 months, 56% at 60 months and 54% at 72 months. Univariate analysis showed that factors which predict for patency include male gender (p = 0.003), good diabetic control (p = 0.025), aspirin use (p = 0.031), pre-dialysis status (p = 0.037), radial artery diameter (p = 0.029) and non-calcified radial arteries (p = 0.002). Age (p = 0.866), cephalic vein diameter (p = 0.630) and surgeon grade (p = 0.472) did not predict for primary AVF failure. Multivariate analysis revealed the male gender to be an independent predictor for patency (odds ratio 1.99, p = 0.01). Subset analysis showed a significantly larger average radial artery diameter of 2.3 mm amongst males, as compared to 1.9 mm amongst females (p = 0.001) and no statistical difference in the average cephalic vein diameter. Within our Asian study population, 12-month patency rate of RCAVF is 72%, 69% at 24 months, 58% at 36 months, 57% at 48 months, 56% at 60 months and 54% at 72 months. Male gender is an independent predictor for RCAVF patency. In females or patients with calcified radial arteries, a more proximal AVF should be considered.

Anatomic characterization of the humeral nutrient artery: Application to fracture and surgery of the humerus.

PubMed

Ichimura, Koichiro; Kinose, Shota; Kawasaki, Yuto; Okamura, Taro; Kato, Kota; Sakai, Tatsuo

2017-10-01

Anatomic characterization of the humeral nutrient artery varies among the several textbooks on human anatomy. To clarify the anatomic characteristics of the humeral nutrient artery, we reexamined its origin and course by cadaveric dissection. In typical cases, one prominent nutrient foramen was situated on the anteromedial surface of the humeral shaft, and the nutrient canal distally penetrated the cortical bone layer. The humeral nutrient artery originated from the brachial artery below the level of the nutrient foramen as a short ascending branch. On reaching near the nutrient foramen, the humeral nutrient artery formed a hairpin loop on the periosteum to enter into the nutrient foramen. In some cases, an accessory nutrient foramen was also found near the groove for the radial nerve on the posterior surface of the humerus. This accessory nutrient foramen received an accessory humeral nutrient artery that originated from the radial collateral artery. The present findings corresponded well with the descriptions in the anatomy textbooks published in English-speaking countries. However, textbooks published in German-speaking countries describe only one type of humeral nutrient artery, the branch of the profunda brachii artery. Terminologia Anatomica, the international standard in human anatomic terminology, most likely adopted the description in the German anatomy textbooks, and thus, it is necessary to correct the position of the humeral nutrient artery in the hierarchy of Terminologia Anatomica for accurate morphological description. Clin. Anat. 30:978-987, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Non-Euclidean stress-free configuration of arteries accounting for curl of axial strips sectioned from vessels.

PubMed

Takamizawa, Keiichi; Nakayama, Yasuhide

2013-11-01

It is well known that arteries are subject to residual stress. In earlier studies, the residual stress in the arterial ring relieved by a radial cut was considered in stress analysis. However, it has been found that axial strips sectioned from arteries also curled into arcs, showing that the axial residual stresses were relieved from the arterial walls. The combined relief of circumferential and axial residual stresses must be considered to accurately analyze stress and strain distributions under physiological loading conditions. In the present study, a mathematical model of a stress-free configuration of artery was proposed using Riemannian geometry. Stress analysis for arterial walls under unloaded and physiologically loaded conditions was performed using exponential strain energy functions for porcine and human common carotid arteries. In the porcine artery, the circumferential stress distribution under physiological loading became uniform compared with that without axial residual strain, whereas a gradient of axial stress distribution increased through the wall thickness. This behavior showed almost the same pattern that was observed in a recent study in which approximate analysis accounting for circumferential and axial residual strains was performed, whereas the circumferential and axial stresses increased from the inner surface to the outer surface under a physiological condition in the human common carotid artery of a two-layer model based on data of other recent studies. In both analyses, Riemannian geometry was appropriate to define the stress-free configurations of the arterial walls with both circumferential and axial residual strains.

Ultrasonographic evaluation of displaced neurovascular bundle in Dupuytren disease.

PubMed

Uehara, Kosuke; Miura, Toshiki; Morizaki, Yutaka; Miyamoto, Hideaki; Ohe, Takashi; Tanaka, Sakae

2013-01-01

Neurovascular injury is a serious complication after surgery for Dupuytren disease. The purpose of this study was to evaluate the relationship between the cord and the neurovascular bundle ultrasonographically. We included 22 healthy volunteers and 14 Dupuytren disease patients (25 fingers) in this study. We evaluated the cord and the digital artery with high-resolution ultrasound. We first investigated the effect of the angle of metacarpophalangeal joint on the position of the radial and ulnar digital arteries in volunteers without evidence of Dupuytren disease. We compared 3 parameters of the radial and ulnar digital arteries, including differences in depth, differences in lateral shift, and the shape of the cross-section of the artery, between volunteers and patients with Dupuytren disease. None of these parameters changed with flexion of the metacarpophalangeal joint of 0°, 30°, and 60°. Digital arteries and cords could be identified ultrasonographically in all patients, and we confirmed ultrasonographic findings by operative findings in 13 fingers. We classified the fingers into 3 subgroups based on the ultrasonographic findings: type A (n = 13), in which the cord was above the artery; type B (n = 5), in which the cord was below the artery; and type C (n = 7), in which the cord was located between the radial and ulnar digital arteries. Types A, B, and C corresponded to natatory cord/abductor digiti minimi cord, spiral cord, and central cord, respectively. Comparisons among volunteers and patient subgroups showed that the difference in depth in type B patients was significantly larger than that of the other groups. When we set the cutoff point of the difference in depth to 3 mm, sensitivity and specificity to detect the spiral cord were 80% and 76%, respectively. The relationship between the neurovascular bundle and the type of Dupuytren disease cord can be evaluated by high-resolution ultrasound. Diagnostic III. Copyright © 2013 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

Feasibility of 4D flow MR imaging of the brain with either Cartesian y-z radial sampling or k-t SENSE: comparison with 4D Flow MR imaging using SENSE.

PubMed

Sekine, Tetsuro; Amano, Yasuo; Takagi, Ryo; Matsumura, Yoshio; Murai, Yasuo; Kumita, Shinichiro

2014-01-01

A drawback of time-resolved 3-dimensional phase contrast magnetic resonance (4D Flow MR) imaging is its lengthy scan time for clinical application in the brain. We assessed the feasibility for flow measurement and visualization of 4D Flow MR imaging using Cartesian y-z radial sampling and that using k-t sensitivity encoding (k-t SENSE) by comparison with the standard scan using SENSE. Sixteen volunteers underwent 3 types of 4D Flow MR imaging of the brain using a 3.0-tesla scanner. As the standard scan, 4D Flow MR imaging with SENSE was performed first and then followed by 2 types of acceleration scan-with Cartesian y-z radial sampling and with k-t SENSE. We measured peak systolic velocity (PSV) and blood flow volume (BFV) in 9 arteries, and the percentage of particles arriving from the emitter plane at the target plane in 3 arteries, visually graded image quality in 9 arteries, and compared these quantitative and visual data between the standard scan and each acceleration scan. 4D Flow MR imaging examinations were completed in all but one volunteer, who did not undergo the last examination because of headache. Each acceleration scan reduced scan time by 50% compared with the standard scan. The k-t SENSE imaging underestimated PSV and BFV (P < 0.05). There were significant correlations for PSV and BFV between the standard scan and each acceleration scan (P < 0.01). The percentage of particles reaching the target plane did not differ between the standard scan and each acceleration scan. For visual assessment, y-z radial sampling deteriorated the image quality of the 3 arteries. Cartesian y-z radial sampling is feasible for measuring flow, and k-t SENSE offers sufficient flow visualization; both allow acquisition of 4D Flow MR imaging with shorter scan time.

The feasibility of transradial laser atherectomy for chronic total occlusion using the 5 Fr sheath system.

PubMed

Sherif, Khaled; Yaqub, Yasir; Suarez, Jose A

2016-05-01

We present a case of chronic total occlusion (CTO) approached with LASER endovascular intervention by radial artery approach using a 5 French sheath. A 57-year-old man presented to our hospital having had retrosternal chest pain for two days. Physical examination was normal at the time of presentation. The laboratory tests were within normal limits, including cardiac enzymes except the lipid panel which showed hypertriglyceridemia. The patient underwent a myocardial perfusion scintigraphy stress test that revealed inferior wall ischemia, with normal left ventricular ejection fraction. A 5-French vascular sheath was placed in the right radial artery. Selective coronary artery angiography was performed, which showed right coronary artery (RCA) CTO. A 5-French JR4 guide catheter successfully engaged the RCA and Laser angioplasty was performed across the CTO into the RCA. A marked improvement of flow was evident thereafter. To best of our knowledge this is the first case report showing the feasibility of laser atherectomy using the 5 French sheath system in a coronary arterial CTO. Copyright © 2016 by Academy of Sciences and Arts of Bosnia and Herzegovina.

Advanced Noncontrast Magnetic Resonance Angiography of the Thoracic and Peripheral Arteries

NASA Astrophysics Data System (ADS)

Lindley, Marc Daniel

The gold standard for evaluation of arterial disease using MR continues to be contrast-enhanced MR angiography (MRA) with gadolinium-based contrast agents (Gd-MRA). There has been a recent resurgence in interest in methods that do not rely on gadolinium for enhancement of blood vessels due to associations Gd-MRA has with nephrogenic systemic fibrosis (NSF) in patients with impaired renal function. The risk due to NSF has been shown to be minimized when selecting the appropriate contrast type and dose. Even though the risk of NSF has been shown to be minimized, demand for noncontrast MRA has continued to rise to reduce examination cost, and improve patient comfort and ability to repeat scans. Several methods have been proposed and used to perform angiography of the aorta and peripheral arteries without the use of gadolinium. These techniques have had limitations in transmit radiofrequency field (B1+) inhomogeneities, acquisition time, and specific hardware requirements, which have stunted the utility of noncontrast enhanced MRA. In this work feasibility of noncontrast (NC) MRA at 3T of the femoral arteries using dielectric padding, and using 3D radial stack of stars and compressed sensing to accelerate acquisitions in the abdomen and thorax were tested. Imaging was performed on 13 subjects in the pelvis and thighs using high permittivity padding, and 11 in the abdomen and 19 in the thorax using 3D radial stack of stars with tiny golden angle using gold standards or previously published techniques. Qualitative scores for each study were determined by radiologists who were blinded to acquisition type. Vessel conspicuity in the thigh and pelvis showed significant increase when high permittivity padding was used in the acquisition. No significant difference in image quality was observed in the abdomen and thorax when using undersampling, except for the descending aorta in thoracic imaging. All image quality scores were determined to be of diagnostic quality. In this work it is shown that NC-MRA can be improved through the use of high permittivity dielectric padding and acquisition time can be decreased through the use of 3D radial stack of stars acquisitions.

Model-Based, Noninvasive Monitoring of Intracranial Pressure

DTIC Science & Technology

2012-10-01

nICP) estimate requires simultaneous measurement of the waveforms of arterial blood pressure ( ABP ), obtained via radial artery catheter or finger...initial database comprises subarachnoid hemorrhage patients in neuro-intensive care at our partner hospital, for whom ICP, ABP and CBFV are currently

Assessing the blood pressure waveform of the carotid artery using an ultrasound image processing method

PubMed Central

Fatouraee, Nasser; Saberi, Hazhir

2017-01-01

Purpose The aim of this study was to introduce and implement a noninvasive method to derive the carotid artery pressure waveform directly by processing diagnostic sonograms of the carotid artery. Methods Ultrasound image sequences of 20 healthy male subjects (age, 36±9 years) were recorded during three cardiac cycles. The internal diameter and blood velocity waveforms were extracted from consecutive sonograms over the cardiac cycles by using custom analysis programs written in MATLAB. Finally, the application of a mathematical equation resulted in time changes of the arterial pressure. The resulting pressures were calibrated using the mean and the diastolic pressure of the radial artery. Results A good correlation was found between the mean carotid blood pressure obtained from the ultrasound image processing and the mean radial blood pressure obtained using a standard digital sphygmomanometer (R=0.91). The mean absolute difference between the carotid calibrated pulse pressures and those measured clinically was -1.333±6.548 mm Hg. Conclusion The results of this study suggest that consecutive sonograms of the carotid artery can be used for estimating a blood pressure waveform. We believe that our results promote a noninvasive technique for clinical applications that overcomes the reproducibility problems of common carotid artery tonometry with technical and anatomical causes. PMID:27776401

Robust estimation of carotid artery wall motion using the elasticity-based state-space approach.

PubMed

Gao, Zhifan; Xiong, Huahua; Liu, Xin; Zhang, Heye; Ghista, Dhanjoo; Wu, Wanqing; Li, Shuo

2017-04-01

The dynamics of the carotid artery wall has been recognized as a valuable indicator to evaluate the status of atherosclerotic disease in the preclinical stage. However, it is still a challenge to accurately measure this dynamics from ultrasound images. This paper aims at developing an elasticity-based state-space approach for accurately measuring the two-dimensional motion of the carotid artery wall from the ultrasound imaging sequences. In our approach, we have employed a linear elasticity model of the carotid artery wall, and converted it into the state space equation. Then, the two-dimensional motion of carotid artery wall is computed by solving this state-space approach using the H ∞ filter and the block matching method. In addition, a parameter training strategy is proposed in this study for dealing with the parameter initialization problem. In our experiment, we have also developed an evaluation function to measure the tracking accuracy of the motion of the carotid artery wall by considering the influence of the sizes of the two blocks (acquired by our approach and the manual tracing) containing the same carotid wall tissue and their overlapping degree. Then, we have compared the performance of our approach with the manual traced results drawn by three medical physicians on 37 healthy subjects and 103 unhealthy subjects. The results have showed that our approach was highly correlated (Pearson's correlation coefficient equals 0.9897 for the radial motion and 0.9536 for the longitudinal motion), and agreed well (width the 95% confidence interval is 89.62 µm for the radial motion and 387.26 µm for the longitudinal motion) with the manual tracing method. We also compared our approach to the three kinds of previous methods, including conventional block matching methods, Kalman-based block matching methods and the optical flow. Altogether, we have been able to successfully demonstrate the efficacy of our elasticity-model based state-space approach (EBS) for more accurate tracking of the 2-dimensional motion of the carotid artery wall, towards more effective assessment of the status of atherosclerotic disease in the preclinical stage. Copyright © 2017 Elsevier B.V. All rights reserved.

The effect of indapamide versus hydrochlorothiazide on ventricular and arterial function in patients with hypertension and diabetes: results of a randomized trial.

PubMed

Vinereanu, Dragos; Dulgheru, Raluca; Magda, Stefania; Dragoi Galrinho, Ruxandra; Florescu, Maria; Cinteza, Mircea; Granger, Christopher; Ciobanu, Andrea O

2014-10-01

The objective of this study is to compare the effects of 2 types of diuretics, indapamide and hydrochlorothiazide, added to an angiotensin-converting enzyme inhibitor, on ventricular and arterial functions in patients with hypertension and diabetes. This is a prospective, randomized, active-controlled, PROBE design study in 56 patients (57 ± 9 years, 52% men) with mild-to-moderate hypertension and type 2 diabetes, with normal ejection fraction, randomized to either indapamide (1.5 mg Slow Release (SR)/day) or hydrochlorothiazide (25 mg/d), added to quinapril (10-40 mg/d). All patients had conventional, tissue Doppler and speckle tracking echocardiography and assessment of endothelial and arterial functions and biomarkers, at baseline and after 6 months. Baseline characteristics were similar between groups; systolic and diastolic blood pressures decreased similarly, by 15% and 9% on indapamide and by 17% and 10% on hydrochlorothiazide (P < .05). Mean longitudinal systolic velocity and longitudinal strain increased by 7% and 14% on indapamide (from 5.6 ± 1.8 to 6.0 ± 1.1 cm/s and from 16.2% ± 1.8% to 18.5% ± 1.1%, both P < .05), but did not change on hydrochlorothiazide (P < .05 for intergroup differences), whereas ejection fraction and radial systolic function did not change. Similarly, mean longitudinal early diastolic velocity increased by 31% on indapamide (P < .05), but did not change on hydrochlorothiazide (P < .05 for intergroup differences). These changes were associated with improved endothelial and arterial functions on indapamide, but not on hydrochlorothiazide. Indapamide was found to improve measures of endothelial and arterial functions and to increase longitudinal left ventricular function compared with hydrochlorothiazide in patients with hypertension and diabetes, after 6 months of treatment. This study suggests that indapamide, a thiazide-like diuretic, has important vascular effects that can improve ventriculoarterial coupling. Copyright © 2014 Mosby, Inc. All rights reserved.

Practical utility of thermodilution versus doppler ultrasound to measure hemodialysis blood access flow.

PubMed

Fontseré, Néstor; Mestres, Gaspar; Barrufet, Marta; Burrel, Marta; Vera, Manel; Arias, Marta; Masso, Elisabeth; Cases, Aleix; Maduell, Francisco; Campistol, Josep M

2013-01-01

The current clinical guidelines recommend indirect access blood flow (Qa) measurement as one of the most important components in vascular access maintenance programs. The best-know methods are doppler ultrasound (DU) and saline dilution method. This study evaluates the efficiency of Qa measurement with thermodilution method (TD) in comparison with the DU. Transversal study in 64 patients in hemodialysis (41 men); mean age 59.9 years with 54 AVFs and 10 PTFE. Qa reference value was obtained with DU in brachial artery (AVFs) or at the zone of arterial puncture (AVGs). Bland-Altman and interclass correlation coefficient (ICC) were used to study accuracy. Mean values obtained with DU-Qa were 1426 ± 753 mL/min AVFs and 1186 ± 789 mL/min AVGs. The mean Qa with TD was 1372 ± 770 AVFs (bias 54.6; ICC 0.923) and 1176 ± 758 AVGs (bias 10.2; ICC 0.992). In the subgroup of 28 patients with radiocephalic latero-terminal AVFs the DU-Qa was 1232 ± 767 mL/min. The Qa was in radial artery 942 (ICC 0.805); radial-ulnar artery 1103 (ICC 0.973); cephalic vein 788 (ICC 0.772) and TD 1026 (ICC 0.971). We detected 5 cases of significant stenosis. After endovascular treatment the Kt was 79 liters (61; p=0.043) and TD-Qa 895 mL/min (663; p=0.043). TD represents a good indirect method of Qa measurement. In the subgroup of patients with radiocephalic AVFs, Qa measurements in the radial and ulnar artery are more accurate. Therefore, in this situation the TD method obtained an excellent correlation in comparison to brachial artery.

A mechanical analysis of conduit arteries accounting for longitudinal residual strains.

PubMed

Wang, Ruoya; Gleason, Rudolph L

2010-04-01

Identification of an appropriate stress-free reference configuration is critically important in providing a reasonable prediction of the intramural stress distribution when performing biomechanical analyses on arteries. The stress-free state is commonly approximated as a radially cut ring that typically opens into a nearly circular sector, relieving much of the circumferential residual strains that exist in the traction-free configuration. An opening angle is often used to characterize this sector. In this study, we first present experimental results showing significant residual deformations in the longitudinal direction of two commonly studied arteries in the pig: the common carotid artery and the left anterior descending coronary artery. We concluded that a radially cut ring cannot completely describe the stress-free state of the arteries. Instead, we propose the use of a longitudinal opening angle, in conjunction with the traditional circumferential opening angle, to experimentally quantify the stress-free state of an artery. Secondly, we propose a new kinematic model to account for the addition of longitudinal residual strains through employing the longitudinal opening angle and performed a stress analysis. We found that with the inclusion of longitudinal residual strains in the stress analysis, the predicted circumferential stress gradient was decreased by 3-fold and the predicted longitudinal stress gradient was increased by 5.7-fold. Thus, inclusion of longitudinal residual strains has a significant effect on the predicted stress distribution in arteries.

Influence of physical activity and gender on arterial function in type 2 diabetes, normal and impaired glucose tolerance

PubMed Central

Eriksson, Maria J.; Fritz, Tomas; Nyberg, Gunnar; Östenson, Claes Göran; Krook, Anna; Zierath, Juleen R.; Caidahl, Kenneth

2015-01-01

To determine whether Nordic walking improves cardiovascular function in middle-aged women and men, we included 121 with normal glucose tolerance, 33 with impaired glucose tolerance and 47 with Type 2 diabetes mellitus in a randomized controlled study. The intervention group added Nordic walking 5 h/week for 4 months to their ordinary activities. Aortic pulse wave velocity, aortic augmentation index, stiffness index, reflection index, intima–media thickness in the radial and carotid arteries, echogenicity of the carotid intima–media and systemic vascular resistance were measured. While baseline blood pressure did not differ by gender or diagnosis, aortic augmentation index was found to be higher in women in all groups. Vascular function was unchanged with intervention, without differences by gender or diagnosis. In conclusion, 4 months of Nordic walking is an insufficient stimulus to improve vascular function. Future studies should consider hard endpoints in addition to measures of vascular health, as well as larger population groups, long-term follow-up and documented compliance to exercise training. PMID:26092821

Post-procedural/pre-hemostasis intra-arterial nitroglycerin after transradial catheterization: A gender based analysis.

PubMed

Dharma, Surya; Kedev, Sasko; Patel, Tejas; Sukmawan, Renan; Gilchrist, Ian C; Rao, Sunil V

2016-01-01

We analyzed the effect of nitroglycerin on radial artery occlusion (RAO) in women undergoing transradial catheterization. A total of 1706 patients undergoing transradial catheterization were randomized to receive either 500μg intra-arterial nitroglycerin or placebo at the end of the radial procedure. We explored the gender-based analysis between women (n=539) and men (n=1167). The primary outcome was the incidence of RAO as confirmed by absence of antegrade flow at one day after the transradial procedure evaluated by duplex ultrasound of the radial artery. The use of nitroglycerin, as compared with placebo, did not significantly reduce the risk of RAO in women patients [odds ratio, 0.69; 95% confidence interval (CI), 0.38 to 1.26; P=0.147]. The risk of RAO was higher in women age <60years as compared with women age ≥60years [5.6% vs. 3.5%; odds ratio, 2.16; 95% CI, 1.18 to 3.94; P=0.008]. In women age <60years (n=237), both counter puncture technique and a duration of hemostasis ≥4h were associated with a similar enhanced risk of developing RAO (odds ratio, 3.51; 95% CI, 1.59 to 7.72; P<0.001). The administration of nitroglycerin at the end of a transradial catheterization in women did not reduce the risk of RAO as determined by ultrasound one day after the radial procedure. Age <60years was associated with a higher risk of RAO compared with age ≥60years in women. Further strategies to reduce RAO in women are needed. Copyright © 2015 Elsevier Inc. All rights reserved.

Effect of Wave Reflection and Arterial Stiffness on the Risk of Development of Hypertension in Japanese Men.

PubMed

Tomiyama, Hirofumi; Komatsu, Shunsuke; Shiina, Kazuki; Matsumoto, Chisa; Kimura, Kazutaka; Fujii, Masatsune; Takahashi, Lisa; Chikamori, Taishiro; Yamashina, Akira

2018-05-08

We conducted analyses of repeated-measures data to examine whether pressure wave reflection acts additively or synergistically with arterial stiffness in the pathogenesis of hypertension. In 3172 middle-aged (42±9 years) healthy Japanese men without hypertension at the study baseline, systolic and diastolic blood pressures, brachial-ankle pulse wave velocity, and radial augmentation index were measured annually during a 9-year study period. Of these, 474 participants (15%) developed hypertension by the end of the study period. Binary logistic regression analysis demonstrated significant individual odds ratios for both baseline brachial-ankle pulse wave velocity and radial augmentation index for the development of hypertension. The rate of onset of hypertension during the study period was highest in the participant group with high values for both brachial-ankle pulse wave velocity and radial augmentation index at study baseline (262 of 965 participants: 27%). The generalized estimating equation analysis revealed that both radial augmentation index (estimate=0.06, SE=0.03, P =0.05) and brachial-ankle pulse wave velocity (estimate=0.07×10 -1 , SE=0.02×10 -1 , P <0.01) showed significant longitudinal association with new onset of hypertension, with no significant interaction. In Japanese men, abnormal wave reflection and increased arterial stiffness may be additively associated with the risk of new onset of hypertension. Abnormal wave reflection and elevated central blood pressure may be longitudinally associated with increase in arterial stiffness, and this longitudinal association may be a mechanism underlying the additive effect of these 2 variables on the risk of new onset of hypertension. © 2018 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

Preoperative ultrasound still valuable for radio-cephalic arteriovenous fistula creation?

PubMed

Pajek, Jernej; Malovrh, Marko

2017-03-06

Radio-cephalic arteriovenous fistula is a prototype hemodialysis access with small incidences of infection and distal ischemia, it spares proximal veins for future access use and it helps in the maturation of veins that may be used for more proximal access creations. This access type is prone to higher early failure rates compared to more proximal fistulas and there are unsolved uncertainties regarding exact ultrasound parameters predictive of fistula outcome. Evolution of ultrasound use has yielded several functional parameters that can be measured in addition to anatomical lumen sizes, which remain core parameters on which the decision to construct fistula in radio-cephalic forearm position is based. We propose to use arterial hyperemic response and wall morphology to aid in this decision when radial artery diameter falls in the interval with predictive uncertainty of 1.6-1.9 mm and to use venous flow pattern, respiratory variation, radial artery status and possibly venous distensibility when cephalic vein augmented diameter lies in the borderline interval of 2-2.4 mm. Ultrasound preoperative mapping and planning should be followed by expert surgical technique and several technique modifications of the classical end-to-side approach are possible to enhance operation outcome and diminish the incidence of stenosis most often present at juxta-anastomotic location. In our experience radio-cephalic arteriovenous fistula remains the golden standard for hemodialysis access and preoperative ultrasound the single best imaging modality to plan the operation and predict its success.

Adolescents with Classical Polycystic Ovary Syndrome Have Alterations in the Surrogate Markers of Cardiovascular Disease but Not in the Endothelial Function. The Possible Benefits of Metformin.

PubMed

Fruzzetti, Franca; Ghiadoni, Lorenzo; Virdis, Agostino; De Negri, Ferdinando; Perini, Daria; Bucci, Fiorella; Giannarelli, Chiara; Gadducci, Angiolo; Taddei, Stefano

2016-10-01

To study whether adolescents with the classical form of polycystic ovary syndrome (PCOS) have alterations in metabolic and vascular structure and function. The effect of metformin was evaluated. Controlled study. University outpatient clinic. Eighteen nonobese adolescents with PCOS were enrolled. Seventeen healthy age-matched adolescents were recruited as control subjects. The metabolic profile and the endothelial structure and function were evaluated. Hormonal and lipid profile, blood pressure (BP) measurement, fasting glucose and insulin levels, C-reactive protein (CRP), homocysteine, tissue-type plasminogen activator, plasminogen activator inhibitor-1 (PAI-1), and plasmin-antiplasmin complexes (PAP) were measured. Flow mediated dilation (FMD), central pulse wave velocity (PWV), radial artery pulse wave, and common carotid intima-media thickness (IMT) were also assessed. Girls with PCOS were also studied 6 months after treatment with metformin (850 mg twice per day). Adolescents with PCOS were insulin resistant and/or hyperinsulinemic and they had higher BP values and levels of CRP and PAI-1 than the control subjects. The levels of tissue-type plasminogen activator and PAP were similar in both groups. FMD, PWV, and IMT were also similar. Metformin significantly (P < .05) reduced insulin, BP, CRP, and PAI-1 levels. The PAP levels significantly (P < .05) increased. Radial artery pulse wave was significantly reduced after metformin treatment. No modifications in FMD, PWV, and IMT were observed. Adolescents with classical PCOS have alterations in some surrogate markers of cardiovascular risk and they are ameliorated by metformin. No deterioration of vascular structure and function has been detected, probably because of the short duration of exposure to the disease. Copyright © 2016 North American Society for Pediatric and Adolescent Gynecology. Published by Elsevier Inc. All rights reserved.

Doppler Assessment of Diastolic Function Reflect the Severity of Injury in Rats With Chronic Heart Failure.

PubMed

Sanchez, Pablo; Lancaster, Jordan J; Weigand, Kyle; Mohran, Saffie-Alrahman Ezz-Eldin; Goldman, Steven; Juneman, Elizabeth

2017-10-01

For chronic heart failure (CHF), more emphasis has been placed on evaluation of systolic as opposed to diastolic function. Within the study of diastology, measurements of left ventricular (LV) longitudinal myocardial relaxation have the most validation. Anterior wall radial myocardial tissue relaxation velocities along with mitral valve inflow (MVI) patterns are applicable diastolic parameters in the differentiation between moderate and severe disease in the ischemic rat model of CHF. Myocardial tissue relaxation velocities correlate with traditional measurements of diastolic function (ie, hemodynamics, Tau, and diastolic pressure-volume relationships). Male Sprague-Dawley rats underwent left coronary artery ligation or sham operation. Echocardiography was performed at 3 and 6 weeks after coronary ligation to evaluate LV ejection fraction (EF) and LV diastolic function through MVI patterns (E, A, and E/A) and Doppler imaging of the anterior wall (e' and a'). The rats were categorized into moderate or severe CHF according to their LV EF at 3 weeks postligation. Invasive hemodynamic measurements with solid-state pressure catheters were obtained at the 6-week endpoint. Moderate (N = 20) and severe CHF (N = 22) rats had significantly (P < .05) different EFs, hemodynamics, and diastolic pressure-volume relationships. Early diastolic anterior wall radial relaxation velocities as well as E/e' ratios separated moderate from severe CHF and both diastolic parameters had strong correlations with invasive hemodynamic measurements of diastolic function. Radial anterior wall e' and E/e' can be used for serial assessment of diastolic function in rats with moderate and severe CHF. Copyright © 2017 Elsevier Inc. All rights reserved.

Central Artery Stiffness, Baroreflex Sensitivity, and Brain White Matter Neuronal Fiber Integrity in Older Adults

PubMed Central

Tarumi, Takashi; de Jong, Daan L.K.; Zhu, David C.; Tseng, Benjamin Y.; Liu, Jie; Hill, Candace; Riley, Jonathan; Womack, Kyle B.; Kerwin, Diana R.; Lu, Hanzhang; Cullum, C. Munro; Zhang, Rong

2015-01-01

Cerebral hypoperfusion elevates the risk of brain white matter (WM) lesions and cognitive impairment. Central artery stiffness impairs baroreflex, which controls systemic arterial perfusion, and may deteriorate neuronal fiber integrity of brain WM. The purpose of this study was to examine the associations among brain WM neuronal fiber integrity, baroreflex sensitivity (BRS), and central artery stiffness in older adults. Fifty-four adults (65±6 years) with normal cognitive function or mild cognitive impairment (MCI) were tested. The neuronal fiber integrity of brain WM was assessed from diffusion metrics acquired by diffusion tensor imaging. BRS was measured in response to acute changes in blood pressure induced by bolus injections of vasoactive drugs. Central artery stiffness was measured by carotid-femoral pulse wave velocity (cfPWV). The WM diffusion metrics including fractional anisotropy (FA) and radial (RD) and axial (AD) diffusivities, BRS, and cfPWV were not different between the control and MCI groups. Thus, the data from both groups were combined for subsequent analyses. Across WM, fiber tracts with decreased FA and increased RD were associated with lower BRS and higher cfPWV, with many of the areas presenting spatial overlap. In particular, the BRS assessed during hypotension was strongly correlated with FA and RD when compared with hypertension. Executive function performance was associated with FA and RD in the areas that correlated with cfPWV and BRS. These findings suggest that baroreflex-mediated control of systemic arterial perfusion, especially during hypotension, may play a crucial role in maintaining neuronal fiber integrity of brain WM in older adults. PMID:25623500

Understanding the requirements of self-expandable stents for heart valve replacement: Radial force, hoop force and equilibrium.

PubMed

Cabrera, María Sol; Oomens, Cees W J; Baaijens, Frank P T

2017-04-01

A proper interpretation of the forces developed during stent crimping and deployment is of paramount importance for a better understanding of the requirements for successful heart valve replacement. The present study combines experimental and computational methods to assess the performance of a nitinol stent for tissue-engineered heart valve implantation. To validate the stent model, the mechanical response to parallel plate compression and radial crimping was evaluated experimentally. Finite element simulations showed good agreement with the experimental findings. The computational models were further used to determine the hoop force on the stent and radial force on a rigid tool during crimping and self-expansion. In addition, stent deployment against ovine and human pulmonary arteries was simulated to determine the hoop force on the stent-artery system and the equilibrium diameter for different degrees of oversizing. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Low arterial compliance in young African-American males.

PubMed

Zion, Adrienne S; Bond, Vernon; Adams, Richard G; Williams, Deborah; Fullilove, Robert E; Sloan, Richard P; Bartels, Matthew N; Downey, John A; De Meersman, Ronald E

2003-08-01

Hypertension remains a common public health challenge because of its prevalence and increase in co-morbid cardiovascular diseases. Black males have disproportionate pathophysiological consequences of hypertension compared with any other group in the United States. Alterations in arterial wall compliance and autonomic function often precede the onset of disease. Accordingly, our purpose was to investigate whether differences exist in arterial compliance and autonomic function between young, healthy African-American males without evidence of hypertension and age- and gender-matched non-African-American males. All procedures were carried out noninvasively following rest. Arterial compliance was calculated as the integrated area starting at the well-defined nadir of the incisura of the dicrotic notch to the end of diastole of the radial artery pulse wave. Power spectral analysis of heart rate and blood pressure variability provided distributions representative of parasympathetic and sympathetic modulations and sympathovagal balance. Baroreflex sensitivity (BRS) was calculated using the sequence method. Thirty-two African-American and twenty-nine non-African-American males were comparable in anthropometrics and negative family history of hypertension. t-Tests revealed lower arterial compliance (5.8 +/- 2.4 vs. 8.6 +/- 4.0 mmHg. s; P = 0.0017), parasympathetic modulation (8.9 +/- 1.1 vs. 9.7 +/- 1.1 ln ms2; P = 0.0063), and BRS (13.7 +/- 7.3 vs. 21.1 +/- 8.5 ms/mmHg; P = 0.0007) and higher sympathovagal balance (2.9 +/- 3.2 vs. 1.5 +/- 1.1; P = 0.03) in the African-American group. In summary, differences exist in arterial compliance and autonomic balance in African-American males. These alterations may be antecedent markers of disease and valuable in the detection of degenerative cardiovascular processes in individuals at risk.

Ultrasound guided V3 segment vertebral artery direct percutaneous puncture for basilar artery mechanical thrombectomy in acute stroke: a technical report.

PubMed

Desai, Jamsheed A; Almekhlafi, Mohammed A; Hill, Michael D; Goyal, Mayank; Eesa, Muneer

2014-04-01

A middle aged patient presented with acute ischemic stroke due to basilar artery occlusion. The patient clinically deteriorated despite intravenous thrombolysis and was referred for mechanical thrombectomy. The right vertebral artery was occluded and could not be accessed despite attempting various shaped catheters, even when a radial artery access was used. The left vertebral artery ended in the posterior inferior cerebellar artery. Eventually, ultrasound guided V3 segment vertebral artery direct puncture was successfully done and the procedure was completed. No access related complications were encountered. Direct cervical arterial puncture can be safely used by experienced operators as a last resort in acute stroke cases with difficult access.

Patients undergoing PCI from the femoral route by default radial operators are at high risk of vascular access-site complications.

PubMed

Rafie, Ihsan M; Uddin, Muez M; Ossei-Gerning, Nicholas; Anderson, Richard A; Kinnaird, Timothy D

2014-02-01

Radial artery (RA) access for PCI has a lower incidence of vascular access-site (VAS) complications than the femoral artery (FA) approach. However, even for default radial operators certain patients are intervened upon from the FA. We examined the demographics and incidence of VAS complications when default radial operators resort to the FA for PCI. The demographics and VAS complications were compared by access site retrospectively for all PCI cases performed by default radial operators (n=1,392). A modified ACUITY trial definition of major VAS complication was used. FA puncture occurred in 25.2% (351/1,392) of cases. Patients were more likely to be female, older and weigh less than patients undergoing PCI from the RA. The FA procedure was likely to be more complex with larger sheaths, more left main stem, graft and multivessel intervention, and there was a greater proportion of emergency cases. Despite increased case complexity, glycoprotein inhibitors were used less frequently in femoral cases (26.5% vs. 36.8%, p<0.001). A VAS complication occurred in 12.5% (44/351) of cases. The risk factors for access-site bleeding are disproportionately high in the population requiring FA puncture by default radial operators, and as a result such patients have a high rate of vascular access-site complications.

Effects of cranberry juice consumption on vascular function in patients with coronary artery disease.

PubMed

Dohadwala, Mustali M; Holbrook, Monika; Hamburg, Naomi M; Shenouda, Sherene M; Chung, William B; Titas, Megan; Kluge, Matthew A; Wang, Na; Palmisano, Joseph; Milbury, Paul E; Blumberg, Jeffrey B; Vita, Joseph A

2011-05-01

Cranberry juice contains polyphenolic compounds that could improve endothelial function and reduce cardiovascular disease risk. The objective was to examine the effects of cranberry juice on vascular function in subjects with coronary artery disease. We completed an acute pilot study with no placebo (n = 15) and a chronic placebo-controlled crossover study (n = 44) that examined the effects of cranberry juice on vascular function in subjects with coronary artery disease. In the chronic crossover study, subjects with coronary heart disease consumed a research preparation of double-strength cranberry juice (54% juice, 835 mg total polyphenols, and 94 mg anthocyanins) or a matched placebo beverage (480 mL/d) for 4 wk each with a 2-wk rest period between beverages. Beverage order was randomly assigned, and participants refrained from consuming other flavonoid-containing beverages during the study. Vascular function was measured before and after each beverage, with follow-up testing ≥12 h after consumption of the last beverage. Mean (±SD) carotid-femoral pulse wave velocity, a measure of central aortic stiffness, decreased after cranberry juice (8.3 ± 2.3 to 7.8 ± 2.2 m/s) in contrast with an increase after placebo (8.0 ± 2.0 to 8.4 ± 2.8 m/s) (P = 0.003). Brachial artery flow-mediated dilation, digital pulse amplitude tonometry, blood pressure, and carotid-radial pulse wave velocity did not change. In the uncontrolled pilot study, we observed improved brachial artery flow-mediated dilation (7.7 ± 2.9% to 8.7 ± 3.1%, P = 0.01) and digital pulse amplitude tonometry ratio (0.10 ± 0.12 to 0.23 ± 0.16, P = 0.001) 4 h after consumption of a single 480-mL portion of cranberry juice. Chronic cranberry juice consumption reduced carotid femoral pulse wave velocity-a clinically relevant measure of arterial stiffness. The uncontrolled pilot study suggested an acute benefit; however, no chronic effect on measures of endothelial vasodilator function was found. This trial was registered at clinicaltrials.gov as NCT00553904.

Effects of cranberry juice consumption on vascular function in patients with coronary artery disease123

PubMed Central

Dohadwala, Mustali M; Holbrook, Monika; Hamburg, Naomi M; Shenouda, Sherene M; Chung, William B; Titas, Megan; Kluge, Matthew A; Wang, Na; Palmisano, Joseph; Milbury, Paul E; Blumberg, Jeffrey B; Vita, Joseph A

2011-01-01

Background: Cranberry juice contains polyphenolic compounds that could improve endothelial function and reduce cardiovascular disease risk. Objective: The objective was to examine the effects of cranberry juice on vascular function in subjects with coronary artery disease. Design: We completed an acute pilot study with no placebo (n = 15) and a chronic placebo-controlled crossover study (n = 44) that examined the effects of cranberry juice on vascular function in subjects with coronary artery disease. Results: In the chronic crossover study, subjects with coronary heart disease consumed a research preparation of double-strength cranberry juice (54% juice, 835 mg total polyphenols, and 94 mg anthocyanins) or a matched placebo beverage (480 mL/d) for 4 wk each with a 2-wk rest period between beverages. Beverage order was randomly assigned, and participants refrained from consuming other flavonoid-containing beverages during the study. Vascular function was measured before and after each beverage, with follow-up testing ≥12 h after consumption of the last beverage. Mean (±SD) carotid-femoral pulse wave velocity, a measure of central aortic stiffness, decreased after cranberry juice (8.3 ± 2.3 to 7.8 ± 2.2 m/s) in contrast with an increase after placebo (8.0 ± 2.0 to 8.4 ± 2.8 m/s) (P = 0.003). Brachial artery flow-mediated dilation, digital pulse amplitude tonometry, blood pressure, and carotid-radial pulse wave velocity did not change. In the uncontrolled pilot study, we observed improved brachial artery flow-mediated dilation (7.7 ± 2.9% to 8.7 ± 3.1%, P = 0.01) and digital pulse amplitude tonometry ratio (0.10 ± 0.12 to 0.23 ± 0.16, P = 0.001) 4 h after consumption of a single 480-mL portion of cranberry juice. Conclusions: Chronic cranberry juice consumption reduced carotid femoral pulse wave velocity—a clinically relevant measure of arterial stiffness. The uncontrolled pilot study suggested an acute benefit; however, no chronic effect on measures of endothelial vasodilator function was found. This trial was registered at clinicaltrials.gov as NCT00553904. PMID:21411615

Intraoperative bypass graft angiography: cooperation between cardiologist and surgeons in the operation room for optimal postoperative results -- is this the way for the future?

PubMed

Shrestha, M; Bara, C; Khaladj, N; Kamiya, H; Hagl, C; Kallenbach, K; Zhang, R; Klima, U; Haverich, A

2007-09-01

To confirm the quality of total arterial CABG carried out using the left internal thoracic artery (LITA) and a radial artery (RA) T-graft and distal anastomoses immediately in the OR, we developed a new technique using intraoperative graft angiography. A 5-Fr sheath is inserted in the proximal radial artery stump, through which a catheter for LITA angiography is later introduced. From July 2004 to March 2005, 23 patients underwent total arterial CABG with the T-graft and intraoperative graft angiography. On-pump CABG was performed in 22 patients and off-pump CABG in 1 patient. Mean procedure time for the angiography was 13.7 +/- 7.3 minutes, and mean fluoroscopy time was 6.2 +/- 4.6 minutes. In two patients, the RA-marginal artery side-to-side anastomosis was stenosed and had to be revised as demonstrated by graft angiography. In one patient, the RA was kinked and in another, there was a kinking of the LITA. In both cases, kinking was corrected. The remaining anastomoses were seen to have unobstructed flow with no evidence of stenosis. Intraoperative graft angiography can be performed in patients undergoing total arterial CABG. This concept of intraoperative cooperation between an interventional cardiologist and surgeons could significantly improve the operative outcome in CABG surgery.

Evaluation of arterial propagation velocity based on the automated analysis of the Pulse Wave Shape

NASA Astrophysics Data System (ADS)

Clara, F. M.; Scandurra, A. G.; Meschino, G. J.; Passoni, L. I.

2011-12-01

This paper proposes the automatic estimation of the arterial propagation velocity from the pulse wave raw records measured in the region of the radial artery. A fully automatic process is proposed to select and analyze typical pulse cycles from the raw data. An adaptive neuro-fuzzy inference system, together with a heuristic search is used to find a functional approximation of the pulse wave. The estimation of the propagation velocity is carried out via the analysis of the functional approximation obtained with the fuzzy model. The analysis of the pulse wave records with the proposed methodology showed small differences compared with the method used so far, based on a strong interaction with the user. To evaluate the proposed methodology, we estimated the propagation velocity in a population of healthy men from a wide range of ages. It has been found in these studies that propagation velocity increases linearly with age and it presents a considerable dispersion of values in healthy individuals. We conclude that this process could be used to evaluate indirectly the propagation velocity of the aorta, which is related to physiological age in healthy individuals and with the expectation of life in cardiovascular patients.

The association of maternal prenatal psychosocial stress with vascular function in the child at age 10-11 years: findings from the Avon longitudinal study of parents and children.

PubMed

van Dijk, Aimée E; Dawe, Karen; Deanfield, John; Stronks, Karien; Gemke, Reinoud J B J; Vrijkotte, Tanja G M; Lawlor, Debbie A

2014-09-01

To investigate whether (1) maternal psychosocial stress (depression/anxiety) during pregnancy is associated with offspring vascular function and (2) whether any association differs depending on the gestational timing of exposure to stress. We also investigated whether any association is likely to be due to intrauterine mechanisms by (3) comparing with the association of paternal stress with offspring vascular function and (4) examining whether any prenatal association is explained by maternal postnatal stress. Associations were examined in a UK birth cohort, with offspring outcomes (systolic and diastolic blood pressure, SBP and DBP, endothelial function assessed by brachial artery flow-mediated dilatation (FMD); arterial stiffness assessed by carotid to radial pulse wave velocity (PWV), brachial artery distensibility (DC), and brachial artery diameter (BD) assessed at age 10-11 years (n = 4,318). Maternal depressive symptoms and anxiety were assessed at 18 and 32 weeks gestation and 8 months postnatally. Paternal symptoms were assessed at week 19. With the exception of DBP and BD, there were no associations of maternal depressive symptoms with any of the vascular outcomes. Maternal depressive and anxiety symptoms were associated with lower offspring DBP and wider BD, though the latter attenuated to the null with adjustment for confounding factors. Paternal symptoms were not associated with offspring outcomes. Maternal postnatal depressive symptoms were associated with lower offspring SBP. We found no evidence to support the hypothesis that maternal stress during pregnancy adversely affects offspring vascular function at age 10-12 years via intrauterine mechanisms. © Authors 2013 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Successful technical and clinical outcome using a second generation balloon expandable coronary stent for transplant renal artery stenosis: Our experience.

PubMed

Salsamendi, Jason; Pereira, Keith; Baker, Reginald; Bhatia, Shivank S; Narayanan, Govindarajan

2015-10-01

Transplant renal artery stenosis (TRAS) is a vascular complication frequently seen because of increase in the number of renal transplantations. Early diagnosis and management is essential to optimize a proper graft function. Currently, the endovascular treatment of TRAS using angioplasty and/or stenting is considered the treatment of choice with the advantage that it does not preclude subsequent surgical correction. Treatment of TRAS with the use of stents, particularly in tortuous transplant renal anatomy presents a unique challenge to an interventional radiologist. In this study, we present three cases from our practice highlighting the use of a balloon-expandable Multi-Link RX Ultra coronary stent system (Abbott Laboratories, Abbott Park, Illinois, USA) for treating high grade focal stenosis along very tortuous renal arterial segments. Cobalt-Chromium alloy stent scaffold provides excellent radial force, whereas the flexible stent design conforms to the vessel course allowing for optimal stent alignment.

Comparison of femoropopliteal artery stents under axial and radial compression, axial tension, bending, and torsion deformations.

PubMed

Maleckis, Kaspars; Deegan, Paul; Poulson, William; Sievers, Cole; Desyatova, Anastasia; MacTaggart, Jason; Kamenskiy, Alexey

2017-11-01

High failure rates of Peripheral Arterial Disease (PAD) stenting appear to be associated with the inability of certain stent designs to accommodate severe biomechanical environment of the femoropopliteal artery (FPA) that bends, twists, and axially compresses during limb flexion. Twelve Nitinol stents (Absolute Pro, Supera, Lifestent, Innova, Zilver, Smart Control, Smart Flex, EverFlex, Viabahn, Tigris, Misago, and Complete SE) were quasi-statically tested under bench-top axial and radial compression, axial tension, bending, and torsional deformations. Stents were compared in terms of force-strain behavior, stiffness, and geometrical shape under each deformation mode. Tigris was the least stiff stent under axial compression (6.6N/m axial stiffness) and bending (0.1N/m) deformations, while Smart Control was the stiffest (575.3N/m and 105.4N/m, respectively). Under radial compression Complete SE was the stiffest (892.8N/m), while Smart Control had the lowest radial stiffness (211.0N/m). Viabahn and Supera had the lowest and highest torsional stiffness (2.2μNm/° and 959.2μNm/°), respectively. None of the 12 PAD stents demonstrated superior characteristics under all deformation modes and many experienced global buckling and diameter pinching. Though it is yet to be determined which of these deformation modes might have greater clinical impact, results of the current analysis may help guide development of new stents with improved mechanical characteristics. Copyright © 2017 Elsevier Ltd. All rights reserved.

Transapical aortic valve implantation and minimally invasive off-pump bypass surgery

PubMed Central

Ahad, Samir; Baumbach, Hardy; Hill, Stephan; Franke, Ulrich F. W.

2014-01-01

Transcatheter aortic valve implantation (TAVI) has gained increasing popularity for high-risk patients with symptomatic aortic valve stenosis. A concomitant coronary artery disease leads to a complicated management and an increased perioperative risk. This case report describes the successful total arterial coronary revascularization of the left anterior descending and the left marginal branch of the circumflex artery utilizing the left internal mammary artery (LIMA) and left radial artery in off-pump technique in combination with the transapical transcatheter aortic valve implantation via minimally invasive anterolateral access in the fifth intercostal space. PMID:24221960

Topical Menthol, Ice, Peripheral Blood Flow, and Perceived Discomfort

PubMed Central

Topp, Robert; Ledford, Elizabeth R.; Jacks, Dean E.

2013-01-01

Context: Injury management commonly includes decreasing arterial blood flow to the affected site in an attempt to reduce microvascular blood flow and edema and limit the induction of inflammation. Applied separately, ice and menthol gel decrease arterial blood flow, but the combined effects of ice and menthol gel on arterial blood flow are unknown. Objectives: To compare radial artery blood flow, arterial diameter, and perceived discomfort before and after the application of 1 of 4 treatment conditions. Design: Experimental crossover design. Setting: Clinical laboratory. Participants or Other Participants: Ten healthy men, 9 healthy women (mean age = 25.68 years, mean height = 1.73 m, mean weight = 76.73 kg). Intervention(s): Four treatment conditions were randomly applied for 20 minutes to the right forearm of participants on 4 different days separated by at least 24 hours: (1) 3.5 mL menthol gel, (2) 0.5 kg of crushed ice, (3) 3.5 mL of menthol gel and 0.5 kg of crushed ice, or (4) no treatment (control). Main Outcome Measure(s): Using high-resolution ultrasound, we measured right radial artery diameter (cm) and blood flow (mL/min) every 5 minutes for 20 minutes after the treatment was applied. Discomfort with the treatment was documented using a 1-to-10 intensity scale. Results: Radial artery blood flow decreased (P < .05) from baseline in the ice (−20% to −24%), menthol (−17% to −24%), and ice and menthol (−36% to −39%) treatments but not in the control (3% to 9%) at 5, 10, and 15 minutes. At 20 minutes after baseline, only the ice (−27%) and combined ice and menthol (−38%) treatments exhibited reductions in blood flow (P < .05). Discomfort was less with menthol than with the ice treatment at 5, 10, and 20 minutes after application (P < .05). Arterial diameter and heart rate did not change. Conclusions: The application of 3.5 mL of menthol was similar to the application of 0.5 kg of crushed ice in reducing peripheral blood flood. Combining crushed ice with menthol appeared to have an additive effect on reducing blood flow. PMID:23672386

Improving patency of coronary conduits "valveless" veins and/or arterial grafts.

PubMed

Lajos, Thomas Z; Robicsek, Francis; Thubrikar, Mano; Urschel, Harold

2007-01-01

Veins used for coronary artery bypass operation have a well-documented limited long-term patency. Internal thoracic artery (ITA) grafts have shown exceptional "durability." Assumptions were made that other arterial conduits have similar characteristics. The purpose of this article is to compare different conduits long-term patency including saphenous veins to other available arterial conduits: inferior epigastric artery (IE), right gastroepiploic artery (RGEA), and radial artery (RA). Recent studies have shown that radial artery bypasses have lower patency rate than saphenous veins. Flow patterns, physiological flow characteristics are reviewed including native vessel disease and area of myocardium supplied. In the case of venous bypasses, the primary culprit of failure seemed to be the quality of the vein itself and the reverse venous valves in the conduit resulting in: (a) trapping-hypertension, (b) thrombosis, (c) turbulence, (d) intimal damage, (e) mismatching in size. Clinical follow-up of our patients up to 8 to 11 years (average 8.9 years) have proved the superior characteristics of the so-called "good veins." In a retrospective study of 436 patients sequential, valveless veins patency was 88.6% versus 72% of reversed valvular segments (p < 0.01). Patients' survival seemed to be significantly improved if these veins were combined with ITA grafts. Patients' survival with one valveless limb HS + ITA was 78% versus HS + SV 52% (p < or = 0.0017) and HS + ITA versus HS + ITA + SV (p < 0.0057). Selective decision-making of the surgeon at the time of the operation is required to choose the best conduit to be able to perform the best operation with the best long-term result.

Modulation of radial blood flow during Braille character discrimination task.

PubMed

Murata, Jun; Matsukawa, K; Komine, H; Tsuchimochi, H

2012-03-01

Human hands are excellent in performing sensory and motor function. We have hypothesized that blood flow of the hand is dynamically regulated by sympathetic outflow during concentrated finger perception. To identify this hypothesis, we measured radial blood flow (RBF), radial vascular conductance (RVC), heart rate (HR), and arterial blood pressure (AP) during Braille reading performed under the blind condition in nine healthy subjects. The subjects were instructed to read a flat plate with raised letters (Braille reading) for 30 s by the forefinger, and to touch a blank plate as control for the Braille discrimination procedure. HR and AP slightly increased during Braille reading but remained unchanged during the touching of the blank plate. RBF and RVC were reduced during the Braille character discrimination task (decreased by -46% and -49%, respectively). Furthermore, the changes in RBF and RVC were much greater during the Braille character discrimination task than during the touching of the blank plate (decreased by -20% and -20%, respectively). These results have suggested that the distribution of blood flow to the hand is modulated via sympathetic nerve activity during concentrated finger perception.

Perioperative Assessment of Myocardial Deformation

PubMed Central

Duncan, Andra E.; Alfirevic, Andrej; Sessler, Daniel I.; Popovic, Zoran B.; Thomas, James D.

2014-01-01

Evaluation of left ventricular performance improves risk assessment and guides anesthetic decisions. However, the most common echocardiographic measure of myocardial function, the left ventricular ejection fraction (LVEF), has important limitations. LVEF is limited by subjective interpretation which reduces accuracy and reproducibility, and LVEF assesses global function without characterizing regional myocardial abnormalities. An alternative objective echocardiographic measure of myocardial function is thus needed. Myocardial deformation analysis, which performs quantitative assessment of global and regional myocardial function, may be useful for perioperative care of surgical patients. Myocardial deformation analysis evaluates left ventricular mechanics by quantifying strain and strain rate. Strain describes percent change in myocardial length in the longitudinal (from base to apex) and circumferential (encircling the short-axis of the ventricle) direction and change in thickness in the radial direction. Segmental strain describes regional myocardial function. Strain is a negative number when the ventricle shortens longitudinally or circumferentially and is positive with radial thickening. Reference values for normal longitudinal strain from a recent meta-analysis using transthoracic echocardiography are (mean ± SD) −19.7 ± 0.4%, while radial and circumferential strain are 47.3 ± 1.9 and −23.3 ± 0.7%, respectively. The speed of myocardial deformation is also important and is characterized by strain rate. Longitudinal systolic strain rate in healthy subjects averages −1.10 ± 0.16 sec−1. Assessment of myocardial deformation requires consideration of both strain (change in deformation), which correlates with LVEF, and strain rate (speed of deformation), which correlates with rate of rise of left ventricular pressure (dP/dt). Myocardial deformation analysis also evaluates ventricular relaxation, twist, and untwist, providing new and noninvasive methods to assess components of myocardial systolic and diastolic function. Myocardial deformation analysis is based on either Doppler or a non-Doppler technique, called speckle-tracking echocardiography. Myocardial deformation analysis provides quantitative measures of global and regional myocardial function for use in the perioperative care of the surgical patient. For example, coronary graft occlusion after coronary artery bypass grafting is detected by an acute reduction in strain in the affected coronary artery territory. In addition, assessment of left ventricular mechanics detects underlying myocardial pathology before abnormalities become apparent on conventional echocardiography. Certainly, patients with aortic regurgitation demonstrate reduced longitudinal strain before reduction in LVEF occurs, which allows detection of subclinical left ventricular dysfunction and predicts increased risk for heart failure and impaired myocardial function after surgical repair. In this review we describe the principles, techniques, and clinical application of myocardial deformation analysis. PMID:24557101

Second internal thoracic artery versus radial artery in coronary artery bypass grafting: a long-term, propensity score-matched follow-up study.

PubMed

Ruttmann, Elfriede; Fischler, Nikolaus; Sakic, Adel; Chevtchik, Orest; Alber, Hannes; Schistek, Roland; Ulmer, Hanno; Grimm, Michael

2011-09-20

The best second arterial conduit for multiple arterial revascularization (MAR) is still a matter of debate. Previous studies on the benefit of either using the radial artery (RA) or the right internal thoracic artery (RITA) in coronary artery bypass grafting are not conclusive. The aim of our study was to compare the perioperative and long-term outcome of either RA or RITA grafts as second conduits for MAR. A consecutive series of 1001 patients undergoing first nonemergent coronary artery bypass grafting receiving either RA or RITA as second graft for MAR between 2001 and 2010 were studied. There were 277 patients receiving a RITA and 724 patients receiving a RA in addition to a left internal thoracic artery (LITA). Concomitant saphenous vein grafts (SVG) were grafted in addition as necessary. Propensity score-matched analysis was performed to compare the 2 groups, bilateral ITA±SVG (BITA±SVG group) and the LITA+RA±SVG group relative to overall survival and major adverse cardiac and cerebrovascular events-free survival. Hazard ratios and their 95% confidence intervals were estimated by COX regression stratified on matched pairs. The incidence of perioperative major adverse cardiac and cerebrovascular events was significantly lower in the BITA±SVG group (1.4% versus 7.6%, P<0.001). Overall survival (hazard ratio 0.23; 95% confidence interval 0.066-0.81; P=0.022) and major adverse cardiac and cerebrovascular events-free survival (hazard ratio 0.18; 95% confidence interval 0.08-0.42; P<0.001) were significantly better in the BITA±SVG group compared to the LITA+RA±SVG group. The results of our study provide strong evidence for the superiority of a RITA graft compared to RA as a second conduit in MAR.

True Brachial Artery Aneurysm in a Patient with Vascular Access for Haemodialysis and Kidney Graft.

PubMed

Correia, Mafalda; Marinho, André; Mendes, Carolina; Antunes, Luís; Gonçalves, Óscar

2017-01-01

True brachial artery aneurysms are rare and some of them have been described as a late complication in patients with vascular access for haemodialysis and kidney graft. The purpose of this paper is to present a clinical case of a patient with a true brachial artery aneurysm and its following treatment. This case concerns a caucasian male patient with 43 years old who had vesicoureteral reflux at 7 years old, and subsequent end-stage renal disease, and started on haemodialysis at the age of twelve. The patient had homolateral radial and brachiocephalic arteriovenous fistulas (AVF), two sequential kidney grafts and was under immunosuppressant therapy for several years. As part of the medical history he also had bilateral amaurosis, Hepatitis B and C and was submitted to total parathyroidectomy and a following auto-transplant. In the latest years the patient presented with several aneurysms related to the vascular access. After the finding of an anastomotic false aneurysm and venous aneurysms complicating the AVF, the patient had removal of the aneurysms and ligation of the AVF. Later, he was diagnosed, in different times, with two true brachial artery aneurysms. At the time of the diagnosis of the first true aneurysm, the patient presented with local pain and occasional paraesthesias relative to compression symptoms. At physical examination the patient had a brachial pulsatile mass and a palpable radial pulse. The Doppler ultrasound exam revealed a true brachial artery aneurysm with 4,5 cm diameter. After two years, the patient was once again diagnosed with a true brachial artery aneurysm with 3,1 cm diameter. At this time the patient was asymptomatic and had palpable brachial mass and radial pulse. At the time of the diagnosis of the first true brachial aneurysm the patient was submitted to partial aneurysmectomy and brachiobrachial graft with PTFE 8. The patency of the graft persisted until the diagnosis of the second aneurysm. After two years, the patient was submitted to partial aneurysmectomy and axilobrachial graft with PTFE 8. During the follow-up period, the patient remained asymptomatic, had palpable radial pulse and the Doppler ultrasound exam confirmed the patency of the graft. The surveillance of patients with long duration AVF and kidney grafts might be advantageous in the early detection of arterial aneurysms. The surgical treatment in this group of patients is a first treatment option that is associated to a low morbidity.

Measurement of radioactivity concentration in blood by using newly developed ToT LuAG-APD based small animal PET tomograph.

PubMed

Malik, Azhar H; Shimazoe, Kenji; Takahashi, Hiroyuki

2013-01-01

In order to obtain plasma time activity curve (PTAC), input function for almost all quantitative PET studies, patient blood is sampled manually from the artery or vein which has various drawbacks. Recently a novel compact Time over Threshold (ToT) based Pr:LuAG-APD animal PET tomograph is developed in our laboratory which has 10% energy resolution, 4.2 ns time resolution and 1.76 mm spatial resolution. The measured value of spatial resolution shows much promise for imaging the blood vascular, i.e; artery of diameter 2.3-2.4mm, and hence, to measure PTAC for quantitative PET studies. To find the measurement time required to obtain reasonable counts for image reconstruction, the most important parameter is the sensitivity of the system. Usually small animal PET systems are characterized by using a point source in air. We used Electron Gamma Shower 5 (EGS5) code to simulate a point source at different positions inside the sensitive volume of tomograph and the axial and radial variations in the sensitivity are studied in air and phantom equivalent water cylinder. An average sensitivity difference of 34% in axial direction and 24.6% in radial direction is observed when point source is displaced inside water cylinder instead of air.

Angioplasty of below-the-elbow arteries in critical hand ischaemia.

PubMed

Ferraresi, R; Palloshi, A; Aprigliano, G; Caravaggi, C; Centola, M; Sozzi, F; Danzi, G B; Manzi, M

2012-01-01

Critical hand ischaemia (CHI) due to pure below-the-elbow (BTE) artery obstruction is a disabling disease and there is still no consensus concerning the most appropriate revascularisation strategy. The aim of this study was to assess the feasibility, safety and outcomes of percutaneous transluminal angioplasty (PTA) in the treatment of CHI due to pure BTE artery disease. Twenty-eight patients (age 62 ± 11 years; three females) with a total of 34 hands affected by CHI (one pain at rest; 18 non-healing ulcer; 15 gangrene) due to pure BTE artery disease underwent PTA. Most of the patients were males with a long history of diabetes mellitus, end-stage renal disease (ESRD) on haemodialysis and systemic atherosclerosis. The interosseous artery was free of disease in all cases, whereas the radial and ulnar arteries were simultaneously involved in 31/34 hands with long stenosis/occlusions (91%; mean length 155 ± 64 mm). The technical success rate was 82% (28/34), with only three minor complications. In the three cases with a functioning radial arteriovenous fistula, we successfully treated the ulnar artery. PTA was unsuccessful in 18% (6/34) hands due to inability to cross severely calcified lesions. The hand-healing rate was 65% (22/34). The predictors of hand healing were PTA technical success (odds ratio (OR) 0.5, confidence interval (CI) 0.28-0.88; p ≤ 0.0001) and digital run-off (OR 0.37, CI 0.19-0.71; p ≤ 0.003). The mean follow-up period was 13 ± 9 months. Six patients (18%) underwent secondary procedures due to symptomatic restenosis. In all these cases, a successful re-PTA was performed at a mean 6 months after the index procedure, and there were no major procedure-related events. Ten patients (36%) died during follow-up. Angioplasty of BTE vessels for CHI is a feasible and safe procedure with acceptable rates of technical success and hand healing. Poor digital run-off due to obstructive disease of the digital vessels can reduce the hand-healing rate after a successful PTA. Pure isolated BTE vessel disease seems to characterise patients with ESRD and diabetes mellitus. Copyright © 2011 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.

Comparison of Verapamil versus Heparin as Adjunctive Treatment for Transradial Coronary Procedures: The VERMUT Study.

PubMed

Tebaldi, Matteo; Biscaglia, Simone; Tumscitz, Carlo; Del Franco, Annamaria; Gallo, Francesco; Spitaleri, Giosafat; Fileti, Luca; Serenelli, Matteo; Tonet, Elisabetta; Erriquez, Andrea; Campo, Gianluca; Ferrari, Roberto

2018-06-13

We sought to demonstrate that the combination of a local vasodilator (verapamil), modern materials, patent hemostasis, and intravenous anticoagulant only in the case of percutaneous coronary intervention, as compared to default heparin administration after sheath insertion, may optimize a combined endpoint, including radial artery oc-clusion (RAO), radial artery spasm (RAS), and access site complication. This is a prospective, single-center, double-blind randomized trial. Overall, 418 patients undergoing a transradial approach (TRA) for coronary procedures were randomized 1: 1 to receive intraradial verapamil (5 mg) or heparin (5,000 IU) after a 6-Fr sheath insertion. The primary outcome was the 24-h occurrence of RAO (ultrasound confirmation), access site complication, and RAS requiring the bailout administration of vasodilators. The combined primary outcome occurred in 127 (30%) patients. It was significantly lower in patients randomized to verapamil as compared to others (26 vs. 35%, p = 0.03). This was mainly due to a significant reduction in RAS (3 vs. 10%, p = 0.006). The 24-h and 30-day occurrence of RAO did not differ between the study groups. Local administration of verapamil versus heparin reduces RAS, without increasing RAO, which appears to be strictly related to radial artery diameter and hemostasis time. © 2018 S. Karger AG, Basel.

Vascular effects of advanced glycation end-products: content of immunohistochemically detected AGEs in radial artery samples as a predictor for arterial calcification and cardiovascular risk in asymptomatic patients with chronic kidney disease.

PubMed

Janda, Katarzyna; Krzanowski, Marcin; Gajda, Mariusz; Dumnicka, Paulina; Jasek, Ewa; Fedak, Danuta; Pietrzycka, Agata; Kuźniewski, Marek; Litwin, Jan A; Sułowicz, Władysław

2015-01-01

Our aim was to determine whether vascular deposition of advanced glycation end-products (AGEs) is associated with arterial calcification and cardiovascular mortality in chronic kidney disease (CKD) patients and to assess the relationships between vascular content of AGEs and selected clinical and biochemical parameters. The study comprised 54 CKD patients (33 hemodialyzed, 21 predialyzed). Examined parameters included BMI, incidence of diabetes, plasma fasting glucose, AGEs, soluble receptor for AGEs and 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging, serum C-reactive protein (hsCRP), plasminogen activator inhibitor-1 (PAI-1), and fetuin-A. Fragments of radial artery obtained during creation of hemodialysis access were stained for calcifications using alizarin red. AGEs deposits were identified immunohistochemically and their relative content was quantified. Vascular content of AGEs was positively correlated with BMI, hsCRP, fetuin-A, PAI-1, and DPPH scavenging in simple regression; only fetuin-A was an independent predictor in multiple regression. There was a significant positive trend in the intensity of AGEs immunostaining among patients with grades 1, 2, and 3 calcifications. AGEs immunostaining intensity predicted 3-year cardiovascular mortality irrespective of patient's age. The present study demonstrates an involvement of AGEs in the development of medial arterial calcification and the impact of arterial AGE deposition on cardiovascular mortality in CKD patients.

Ideal Cardiovascular Health and Arterial Stiffness in Spanish Adults-The EVIDENT Study.

PubMed

García-Hermoso, Antonio; Martínez-Vizcaíno, Vicente; Gomez-Marcos, Manuel Ángel; Cavero-Redondo, Iván; Recio-Rodriguez, José Ignacio; García-Ortiz, Luis

2018-05-01

Studies concerning ideal cardiovascular (CV) health and its relationship with arterial stiffness are lacking. This study examined the association between arterial stiffness with ideal CV health as defined by the American Heart Association, across age groups and gender. The cross-sectional study included 1365 adults. Ideal CV health was defined as meeting ideal levels of the following components: 4 behaviors (smoking, body mass index, physical activity, and Mediterranean diet adherence) and 3 factors (total cholesterol, blood pressure, and glycated hemoglobin). Patients were grouped into 3 categories according to their number of ideal CV health metrics: ideal (5-7 metrics), intermediate (3-4 metrics), and poor (0-2 metrics). We analyzed the pulse wave velocity (PWV), the central and radial augmentation indexes, and the ambulatory arterial stiffness index (AASI). The ideal CV health profile was inversely associated with lower arterial radial augmentation index and AASI in both genders, particularly in middle-aged (45-65 years) and in elderly subjects (>65 years). Also in elderly subjects, adjusted models showed that adults with at least 3 health metrics at ideal levels had significantly lower PWV than those with 2 or fewer ideal health metrics. An association was found between a favorable level of ideal CV health metrics and lower arterial stiffness across age groups. Copyright © 2018 National Stroke Association. Published by Elsevier Inc. All rights reserved.

Accessory superficial ulnar artery: a case report.

PubMed

Solan, Shweta

2013-12-01

Variations in the arterial system of the upper limb have been well documented. A thorough knowledge on variations of arteries of upper extremity is necessary during performance of vascular and reconstructive surgeries and also, during evaluation of angiographic images. A case of accessory superficial ulnar artery was reported. The ulnar artery had a high origin from the brachial artery, in the upper third of the arm and it proceeded superficially and lateral to ulnar nerve in forearm, but it had a normal termination in the hand. The brachial artery had a usual course in the arm, but in the cubital fossa, it divided into the radial and deep ulnar arteries. This deep ulnar artery ended by dividing into ulnar recurrent and common interosseous arteries. Knowledge on this variation is important for the radiologists, orthopaedic and plastic surgeons, for appropriate planning of operative procedures involving the arteries of the upper limb.

Accessory Superficial Ulnar Artery: A Case Report

PubMed Central

Solan, Shweta

2013-01-01

Variations in the arterial system of the upper limb have been well documented. A thorough knowledge on variations of arteries of upper extremity is necessary during performance of vascular and reconstructive surgeries and also, during evaluation of angiographic images. A case of accessory superficial ulnar artery was reported. The ulnar artery had a high origin from the brachial artery, in the upper third of the arm and it proceeded superficially and lateral to ulnar nerve in forearm, but it had a normal termination in the hand. The brachial artery had a usual course in the arm, but in the cubital fossa, it divided into the radial and deep ulnar arteries. This deep ulnar artery ended by dividing into ulnar recurrent and common interosseous arteries. Knowledge on this variation is important for the radiologists, orthopaedic and plastic surgeons, for appropriate planning of operative procedures involving the arteries of the upper limb. PMID:24551682

Flexible PZT Thin Film Tactile Sensor for Biomedical Monitoring

PubMed Central

Tseng, Hong-Jie; Tian, Wei-Cheng; Wu, Wen-Jong

2013-01-01

This paper presents the development of tactile sensors using the sol-gel process to deposit a PZT thin-film from 250 nm to 1 μm on a flexible stainless steel substrate. The PZT thin-film tactile sensor can be used to measure human pulses from several areas, including carotid, brachial, finger, ankle, radial artery, and the apical region. Flexible PZT tactile sensors can overcome the diverse topology of various human regions and sense the corresponding signals from human bodies. The measured arterial pulse waveform can be used to diagnose hypertension and cardiac failure in patients. The proposed sensors have several advantages, such as flexibility, reliability, high strain, low cost, simple fabrication, and low temperature processing. The PZT thin-film deposition process includes a pyrolysis process at 150 °C/500 °C for 10/5 min, followed by an annealing process at 650 °C for 10 min. Finally, the consistent pulse wave velocity (PWV) was demonstrated based on human pulse measurements from apical to radial, brachial to radial, and radial to ankle. It is characterized that the sensitivity of our PZT-based tactile sensor was approximately 0.798 mV/g. PMID:23698262

Flexible PZT thin film tactile sensor for biomedical monitoring.

PubMed

Tseng, Hong-Jie; Tian, Wei-Cheng; Wu, Wen-Jong

2013-04-25

This paper presents the development of tactile sensors using the sol-gel process to deposit a PZT thin-film from 250 nm to 1 μm on a flexible stainless steel substrate. The PZT thin-film tactile sensor can be used to measure human pulses from several areas, including carotid, brachial, finger, ankle, radial artery, and the apical region. Flexible PZT tactile sensors can overcome the diverse topology of various human regions and sense the corresponding signals from human bodies. The measured arterial pulse waveform can be used to diagnose hypertension and cardiac failure in patients. The proposed sensors have several advantages, such as flexibility, reliability, high strain, low cost, simple fabrication, and low temperature processing. The PZT thin-film deposition process includes a pyrolysis process at 150 °C/500 °C for 10/5 min, followed by an annealing process at 650 °C for 10 min. Finally, the consistent pulse wave velocity (PWV) was demonstrated based on human pulse measurements from apical to radial, brachial to radial, and radial to ankle. It is characterized that the sensitivity of our PZT-based tactile sensor was approximately 0.798 mV/g.

Asynchronous arterial systolic expansion as a marker of vascular aging: assessment of the carotid artery with velocity vector imaging.

PubMed

Yang, Woo-In; Shim, Chi Y; Bang, Woo D; Oh, Chang M; Chang, Hyuk J; Chung, Namsik; Ha, Jong-Won

2011-12-01

Arterial elastic properties change with aging. Measurements of pulse wave velocity and augmentation index are useful for the evaluation of arterial stiffness. However, they likely represent only global characteristics of the arterial tree rather than local vascular alterations. The aim of this study was to evaluate whether local vascular properties assessed by velocity vector imaging differed with aging. Vascular properties of carotid arteries with ages were assessed in 100 healthy volunteers (52 men) ranging from 20 to 68 years using velocity vector imaging. The peak circumferential strain and strain rate of the six segments in left common carotid arteries were analyzed and the standard deviation of the time to peak circumferential strain and strain rate of the six segments, representing the synchronicity of the arterial expansion, were calculated. Central blood pressure, augmentation index and pulse wave velocity were assessed by commercially available radial artery tonometry, the SphygmoCor system (AtCor Medical, West Ryde, Australia). A validated generalized transfer function was used to acquire the central aortic pressures and pressure waveforms. Pulse wave velocity, augmentation index and velocity vector imaging parameters showed significant changes with age. However, the age-related changes in pulse wave velocity, augmentation index and velocity vector imaging parameters were different. The increase in pulse wave velocity was more prominent in older individuals, whereas the changes in augmentation index and carotid strain and strain rate were evident earlier, at the age of 30 years. Unlike augmentation index, which showed little change in older individuals, the standard deviation of time to peak strain and strain rate showed a steady increase from younger to older individuals. Asynchronous arterial expansion could be a useful discriminative marker of vascular aging independent of individual's age.

Comparison of Right and Left Upper Limb Arterial Variants in Patients Undergoing Bilateral Transradial Procedures.

PubMed

Burzotta, Francesco; Brancati, Marta Francesca; Porto, Italo; Saffioti, Silvia; Aurigemma, Cristina; Niccoli, Giampaolo; Leone, Antonio Maria; Coluccia, Valentina; Crea, Filippo; Trani, Carlo

2015-12-01

Transradial approach (TRA), when compared with transfemoral, improves the safety of percutaneous coronary procedures. Arterial axis variants are known to hinder the performance of transradial approach percutaneous coronary procedures. Data on the occurrence of arterial axis variants in the right and left arm arterial axes of individual patients are lacking. From a single-center prospective registry, we selected all patients in whom bilateral upper limb arterial anatomy was assessed based on the performance of left and right radial catheterization obtained during the same or during repeat coronary diagnostic or interventional procedure(s). The occurrence of upper right and left limb arterial axis variants was classified according to the previously described operative ABC classification. A total of 610 patients were identified. An ABC upper limb arterial axis variant was detected in 156 (25.6%) patients. Variants were right-sided only in 65 (11.0%), left-sided only in 40 (6.6%), and bilateral in 46 (7.5%) patients. Thus, arterial axis variants were significantly more common in the right side (P=0.02). Bilateral arterial variants were significantly associated with age, female sex, and valvulopathy. Both A (radial/brachial) and B (axillary/subclavian/innominate) variants exhibited concordance across the 2 sides (odds ratio, 7.2; 95% confidence interval, 4.1-12.7 and 8.0; 95% confidence interval, 2.1-30.9, respectively). The occurrence of an anatomic variant potentially hindering transradial approach coronary diagnostic or interventional procedures is bilateral in <8% of cases and is more common in the right arm. Such information may guide, during the clinical practice, the access selection in the case of repeat procedures or need for additional accesses. © 2015 American Heart Association, Inc.

Kinetic quantitation of cerebral PET-FDG studies without concurrent blood sampling: statistical recovery of the arterial input function.

PubMed

O'Sullivan, F; Kirrane, J; Muzi, M; O'Sullivan, J N; Spence, A M; Mankoff, D A; Krohn, K A

2010-03-01

Kinetic quantitation of dynamic positron emission tomography (PET) studies via compartmental modeling usually requires the time-course of the radio-tracer concentration in the arterial blood as an arterial input function (AIF). For human and animal imaging applications, significant practical difficulties are associated with direct arterial sampling and as a result there is substantial interest in alternative methods that require no blood sampling at the time of the study. A fixed population template input function derived from prior experience with directly sampled arterial curves is one possibility. Image-based extraction, including requisite adjustment for spillover and recovery, is another approach. The present work considers a hybrid statistical approach based on a penalty formulation in which the information derived from a priori studies is combined in a Bayesian manner with information contained in the sampled image data in order to obtain an input function estimate. The absolute scaling of the input is achieved by an empirical calibration equation involving the injected dose together with the subject's weight, height and gender. The technique is illustrated in the context of (18)F -Fluorodeoxyglucose (FDG) PET studies in humans. A collection of 79 arterially sampled FDG blood curves are used as a basis for a priori characterization of input function variability, including scaling characteristics. Data from a series of 12 dynamic cerebral FDG PET studies in normal subjects are used to evaluate the performance of the penalty-based AIF estimation technique. The focus of evaluations is on quantitation of FDG kinetics over a set of 10 regional brain structures. As well as the new method, a fixed population template AIF and a direct AIF estimate based on segmentation are also considered. Kinetics analyses resulting from these three AIFs are compared with those resulting from radially sampled AIFs. The proposed penalty-based AIF extraction method is found to achieve significant improvements over the fixed template and the segmentation methods. As well as achieving acceptable kinetic parameter accuracy, the quality of fit of the region of interest (ROI) time-course data based on the extracted AIF, matches results based on arterially sampled AIFs. In comparison, significant deviation in the estimation of FDG flux and degradation in ROI data fit are found with the template and segmentation methods. The proposed AIF extraction method is recommended for practical use.

The safety and feasibility of guidezilla catheter in complex coronary interventions and an observational study.

PubMed

Ma, Jianying; Hou, Lei; Qian, Juying; Ge, Lei; Zhang, Feng; Chang, Shufu; Xu, Rende; Qin, Qing; Ge, Junbo

2017-10-01

The monorail Guidezilla guide extension catheter was designed to provide additional backup and facilitate device delivery in percutaneous coronary intervention (PCI) for complex coronary anatomy such as chronic total occlusion (CTO), extreme vessel tortuosity, diseased bypass grafts, and anomalous coronary arteries, among others.The present retrospective, single-center study included 188 consecutive patients who underwent PCI using the Guidezilla catheter from March 2015 to August 2016. Study outcomes were rates of target lesion crossing success, procedural success, and complications.The Guidezilla catheter was used most commonly in PCI of CTOs (45%) and heavy proximal calcification (37%), followed by tortuosity (10%), previously deployed proximal stents (4%), and coronary artery anomaly (4%). The right coronary artery (48%) was most commonly intervened followed by the left ascending (35%) and left circumflex (17%) arteries. Rates of target lesion crossing success and procedural success were both 99%, with one device-related periprocedural complication, namely proximal vessel dissection secondary to deep insertion which was successfully treated with stent implantation. Ninety percent of PCI were performed and completed successfully by radial access.In a single center with experienced operators, the use of the Guidezilla guide extension catheter in PCI of complex coronary anatomy performed mostly via radial artery access appeared safe and efficacious, and greatly facilitated device delivery.

The safety and feasibility of guidezilla catheter in complex coronary interventions and an observational study

PubMed Central

Ma, Jianying; Hou, Lei; Qian, Juying; Ge, Lei; Zhang, Feng; Chang, Shufu; Xu, Rende; Qin, Qing; Ge, Junbo

2017-01-01

Abstract The monorail GuidezillaTM guide extension catheter was designed to provide additional backup and facilitate device delivery in percutaneous coronary intervention (PCI) for complex coronary anatomy such as chronic total occlusion (CTO), extreme vessel tortuosity, diseased bypass grafts, and anomalous coronary arteries, among others. The present retrospective, single-center study included 188 consecutive patients who underwent PCI using the Guidezilla catheter from March 2015 to August 2016. Study outcomes were rates of target lesion crossing success, procedural success, and complications. The Guidezilla catheter was used most commonly in PCI of CTOs (45%) and heavy proximal calcification (37%), followed by tortuosity (10%), previously deployed proximal stents (4%), and coronary artery anomaly (4%). The right coronary artery (48%) was most commonly intervened followed by the left ascending (35%) and left circumflex (17%) arteries. Rates of target lesion crossing success and procedural success were both 99%, with one device-related periprocedural complication, namely proximal vessel dissection secondary to deep insertion which was successfully treated with stent implantation. Ninety percent of PCI were performed and completed successfully by radial access. In a single center with experienced operators, the use of the Guidezilla guide extension catheter in PCI of complex coronary anatomy performed mostly via radial artery access appeared safe and efficacious, and greatly facilitated device delivery. PMID:28984768

Morphological and functional consequences of transradial coronary angiography on the radial artery: implications for its use as a bypass conduit.

PubMed

Gaudino, Mario; Leone, Alessandro; Lupascu, Andrea; Toesca, Amelia; Mazza, Andrea; Ponziani, Francesca Romana; Flore, Roberto; Tondi, Paolo; Massetti, Massimo

2015-09-01

To assess the degree of damage to the radial artery (RA) in coronary artery bypass grafting (CABG) patients who underwent preoperative transradial coronary angiography (RA-CA). From May 2012 to October 2013, 50 consecutive CABG patients who underwent RA-CA were prospectively enrolled in the study. All patients underwent echo-Doppler evaluation of the RA of the catheterized arm; the contralateral RA was used as control. The distal segment of the RA was submitted to immunohistochemical assessment of endothelial integrity. Patients were divided in three groups according to the time interval from angiography to evaluation: ≤24 h, >24 h to <7 days and ≥7 days. Baseline RA median diameters were 0.25 ± 0.04 cm in the cannulated arm and 0.22 ± 0.04 cm in the non-cannulated arm (P = 0.01). The flow-mediated dilatation (FMD) in the RA in the catheterized arm and in the control arm were 11.6 ± 7.9 and 14.2 ± 8.9 (P = 0.01), respectively. A statistically significant correlation was found between FMD of the catheterized RA and the time from RA-CA (Pearson's r = 0.348). Linear regression analysis confirmed that the FMD of the catheterized RA was dependent on days elapsed from the procedure (P = 0.032; OR 1.11, CI 0.009-0.203). Immunohistochemical evaluation showed extensive endothelial lesion in all examined RAs, with a trend towards reduction of the damage with time. Endothelial function and integrity of the cannulated arm did not reach those of the control arm in any of the study patients. RA-CA produces extensive damage to the RA. The lesions tend to heal with time but incomplete recovery of endothelial integrity and function is still present more than 30 days after the procedure. After RA-CA, the cannulated RA should not be used for CABG. © The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

Learning curve in transradial cardiac catheterization: procedure-related parameters stratified by operators' transradial volume.

PubMed

Kasasbeh, Ehab S; Parvez, Babar; Huang, Robert L; Hasselblad, Michele Marie; Glazer, Mark D; Salloum, Joseph G; Cleator, John H; Zhao, David X

2012-11-01

To determine whether radial artery access is associated with a reduction in fluoroscopy time, procedure time, and other procedural variables over a 27-month period during which the radial artery approach was incorporated in a single academic Medical Center. Although previous studies have demonstrated a relationship between increased volume and decreased procedural time, no studies have looked at the integration of radial access over time. Data were collected from consecutive patients who presented to the Vanderbilt University Medical Center cardiac catheterization laboratory from January 1, 2009 to April 1, 2011. Patients who underwent radial access diagnostic catheterization with and without percutaneous coronary intervention were included in this study. A total of 1112 diagnostic cardiac catheterizations through the radial access site were analyzed. High-volume, intermediate-volume, and low-volume operators were grouped based on the percentage of procedures performed through a radial approach. From 2009 to 2011, there was a significant decrease in fluoroscopy time in all operator groups for diagnostic catheterization (P=.035). The high-volume operator group had 1.88 and 3.66 minute reductions in fluoroscopy time compared to the intermediate- and low-volume operator groups, respectively (both P<.001). Likewise, the intermediate-volume operator group had a 1.77 minute improvement compared to the low-volume operator group, but this did not reach statistical significance (P=.102). The improvement in fluoroscopy time and other procedure-related parameters was seen after approximately 25 cases with further improvement after 75 cases. The incorporation of the radial access approach in the cardiac catheterization laboratory led to a decrease in fluoroscopy time for each operator and operator group over the last 3 years. Our data demonstrated that higher-volume radial operators have better procedure, room, and fluoroscopy times when compared to intermediate- and low-volume operators. However, lower-volume operators have a reduction in procedure-related parameters with increased radial cases. Number of procedures needed to become sufficient was demonstrated in the current study.

STA-ACA bypass using the ipsilateral free STA graft as an interposition graft and A3-A3 anastomosis for treatment of bilateral ACA steno-occlusive ischemia.

PubMed

Horiuchi, Tetsuyoshi; Ichinose, Shunsuke; Agata, Masahiro; Ito, Kiyoshi; Hongo, Kazuhiro

2018-04-01

Anterior cerebral artery (ACA)-related ischemia is a rare entity in patients with atherosclerosis. Some surgical treatments are reported to date. We present the modification of intracranial-intracranial and intracranial-extracranial bypasses for symptomatic bilateral ACA steno-occlusive disease. The A3-A3 bypass followed by the superficial temporal artery-ACA bypass using the ipsilateral free superficial temporal artery graft is useful without harvesting of the radial artery. Bilateral ACA steno-occlusive induced ischemia can be treated with tailored bypass procedures.

Comparison of Hemostasis Times With a Kaolin-Based Hemostatic Pad (QuikClot Radial) vs Mechanical Compression (TR Band) Following Transradial Access: A Pilot Prospective Study.

PubMed

Roberts, Jonathan S; Niu, Jianli; Pastor-Cervantes, Juan A

2017-10-01

Hemostasis following transradial access (TRA) is usually achieved by mechanical compression. We investigated use of the QuikClot Radial hemostasis pad (Z-Medica) compared with the TR Band (Terumo Medical) to shorten hemostasis after TRA. Thirty patients undergoing TRA coronary angiography and/or percutaneous coronary intervention were randomized into three cohorts post TRA: 10 patients received mechanical compression with the TR Band, 10 patients received 30 min of compression with the QuikClot Radial pad, and 10 patients received 60 min of compression with the QuikClot Radial pad. Times to hemostasis and access-site complications were recorded. Radial artery patency was evaluated 1 hour after hemostasis by the reverse Barbeau's test. There were no differences in patient characteristics, mean dose of heparin (7117 ± 1054 IU), or mean activated clotting time value (210 ± 50 sec) at the end of procedure among the three groups. Successful hemostasis was achieved in 100% of patients with both the 30-min and 60-min compression groups using the QuikClot pad. Hemostasis failure occurred in 50% of patients when the TR Band was initially weaned at the protocol-driven time (40 min after sheath removal). Mean compression time for hemostasis with the TR Band was 149.4 min compared with 30.7 min and 60.9 min for the 30-min and 60-min QuikClot groups, respectively. No radial artery occlusion occurred in any subject at the end of the study. Use of the QuikClot Radial pad following TRA in this pilot trial significantly shortened hemostasis times when compared with the TR Band, with no increased complications noted.

Quantifying subtle changes in cardiovascular mechanics in acromegaly: a Doppler myocardial imaging study.

PubMed

Jurcut, R; Găloiu, S; Florian, A; Vlădaia, A; Ioniţă, O R; Amzulescu, M S; Baciu, I; Popescu, B A; Coculescu, M; Ginghina, C

2014-11-01

To describe morphological and functional cardiovascular changes in acromegaly (ACM) patients, as well as to investigate the ability of Doppler-based myocardial deformation imaging (DMI) to characterize subtle dysfunction in ACM. 69 patients (pts) with ACM (mean age 47 ± 10 years, 27 men) and 31 controls (mean age 43 ± 16 years, matched for age and gender) were recruited. Standard echocardiography and DMI data were obtained for all patients. Peak systolic longitudinal strain values (S) were determined for the left and right ventricles. Radial S was measured at the level of the mid inferolateral segment. Using a high-resolution echo-tracking system, the main indices of arterial stiffness were measured. Of the ACM subjects, 57 had active disease (group A), and 12 controlled ACM (group B). All pts with ACM presented structural changes: a higher LV indexed mass (112 ± 36, 118 ± 23 vs 74 ± 18 g/m(2), p < 0.001) and a higher relative wall thickness (0.45 ± 0.09, 0.50 ± 0.07 vs 0.40 ± 0.07, p = 0.003) compared to controls. Also, ACM pts had functional changes: reduced LV ejection fraction (57 ± 5, 55 ± 5 vs 64 ± 4%, p < 0.001) and altered diastolic function (E/A 1.0 ± 0.4, 1.1 ± 0.1 vs 1.3 ± 0.3, p = 0.005) compared to controls. Both longitudinal and radial LV S values were lower in ACM compared to controls: -16.5 ± 3.5, -16.8 ± 4.3 vs -21.5 ± 3.8%, p < 0.001 for longitudinal and 38.3 ± 12.3, 35.6 ± 11.8 vs 52.2 ± 11.7%, p = 0.002 for radial strain. ACM pts present LV concentric hypertrophy and LV systolic and diastolic dysfunction, even in controlled disease. Altered global LV systolic function appears to be due both to longitudinal and radial dysfunction.

Radial Artery Catheterization

MedlinePlus

... Bridging Disciplines Circulation at Major Meetings Special Themed Issues Global Impact of the 2017 ACC/AHA Hypertension Guidelines Circulation Supplements Cardiovascular Case Series ECG Challenge Hospitals of History Brigham and ...

Ultrasound speckle tracking for radial, longitudinal and circumferential strain estimation of the carotid artery--an in vitro validation via sonomicrometry using clinical and high-frequency ultrasound.

PubMed

Larsson, Matilda; Heyde, Brecht; Kremer, Florence; Brodin, Lars-Åke; D'hooge, Jan

2015-02-01

Ultrasound speckle tracking for carotid strain assessment has in the past decade gained interest in studies of arterial stiffness and cardiovascular diseases. The aim of this study was to validate and directly contrast carotid strain assessment by speckle tracking applied on clinical and high-frequency ultrasound images in vitro. Four polyvinyl alcohol phantoms mimicking the carotid artery were constructed with different mechanical properties and connected to a pump generating carotid flow profiles. Gray-scale ultrasound long- and short-axis images of the phantoms were obtained using a standard clinical ultrasound system, Vivid 7 (GE Healthcare, Horten, Norway) and a high-frequency ultrasound system, Vevo 2100 (FUJIFILM, VisualSonics, Toronto, Canada) with linear-array transducers (12L/MS250). Radial, longitudinal and circumferential strains were estimated using an in-house speckle tracking algorithm and compared with reference strain acquired by sonomicrometry. Overall, the estimated strain corresponded well with the reference strain. The correlation between estimated peak strain in clinical ultrasound images and reference strain was 0.91 (p<0.001) for radial strain, 0.73 (p<0.001) for longitudinal strain and 0.90 (p<0.001) for circumferential strain and for high-frequency ultrasound images 0.95 (p<0.001) for radial strain, 0.93 (p<0.001) for longitudinal strain and 0.90 (p<0.001) for circumferential strain. A significant larger bias and root mean square error was found for circumferential strain estimation on clinical ultrasound images compared to high frequency ultrasound images, but no significant difference in bias and root mean square error was found for radial and longitudinal strain when comparing estimation on clinical and high-frequency ultrasound images. The agreement between sonomicrometry and speckle tracking demonstrates that carotid strain assessment by ultrasound speckle tracking is feasible. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.

Pulse wave velocity and cognitive function in older adults.

PubMed

Zhong, Wenjun; Cruickshanks, Karen J; Schubert, Carla R; Carlsson, Cynthia M; Chappell, Richard J; Klein, Barbara E K; Klein, Ronald; Acher, Charles W

2014-01-01

Arterial stiffness may be associated with cognitive function. In this study, pulse wave velocity (PWV) was measured from the carotid to femoral (CF-PWV) and from the carotid to radial (CR-PWV) with the Complior SP System. Cognitive function was measured by 6 tests of executive function, psychomotor speed, memory, and language fluency. A total of 1433 participants were included (mean age 75 y, 43% men). Adjusting for age, sex, education, pulse rate, hemoglobin A1C, high-density lipoprotein cholesterol, hypertension, cardiovascular disease history, smoking, drinking, and depression symptoms, a CF-PWV>12 m/s was associated with a lower Mini-Mental State Examination score (coefficient: -0.31, SE: 0.11, P=0.005), fewer words recalled on Auditory Verbal Learning Test (coefficient: -1.10, SE: 0.43, P=0.01), and lower score on the composite cognition score (coefficient: -0.10, SE: 0.05, P=0.04) and marginally significantly associated with longer time to complete Trail Making Test-part B (coefficient: 6.30, SE: 3.41, P=0.06), CF-PWV was not associated with Trail Making Test-part A, Digit Symbol Substation Test, or Verbal Fluency Test. No associations were found between CR-PWV and cognitive performance measures. Higher large artery stiffness was associated with worse cognitive function, and longitudinal studies are needed to confirm these associations.

Model-Based, Noninvasive Monitoring of Intracranial Pressure

DTIC Science & Technology

2013-07-01

patients. A physiologically based model relates ICP to simultaneously measured waveforms of arterial blood pressure ( ABP ), obtained via radial... ABP and CBFV are currently measured as the clinical standard of care. The project’s major accomplishments include: assembling a suitable system for...synchronized arterial blood pressure ( ABP ) and cerebral blood flow velocity (CBFV) waveform measurements that can be obtained quite routinely. Our processing

Blood pressure evaluation using sphygmomanometry assisted by arterial pulse waveform detection by fiber Bragg grating pulse device

NASA Astrophysics Data System (ADS)

Sharath, Umesh; Sukreet, Raju; Apoorva, Girish; Asokan, Sundarrajan

2013-06-01

We report a blood pressure evaluation methodology by recording the radial arterial pulse waveform in real time using a fiber Bragg grating pulse device (FBGPD). Here, the pressure responses of the arterial pulse in the form of beat-to-beat pulse amplitude and arterial diametrical variations are monitored. Particularly, the unique signatures of pulse pressure variations have been recorded in the arterial pulse waveform, which indicate the systolic and diastolic blood pressure while the patient is subjected to the sphygmomanometric blood pressure examination. The proposed method of blood pressure evaluation using FBGPD has been validated with the auscultatory method of detecting the acoustic pulses (Korotkoff sounds) by an electronic stethoscope.

Use of an Intravascular Fluorescent Continuous Glucose Sensor in ICU Patients.

PubMed

Strasma, Paul J; Finfer, Simon; Flower, Oliver; Hipszer, Brian; Kosiborod, Mikhail; Macken, Lewis; Sechterberger, Marjolein; van der Voort, Peter H J; DeVries, J Hans; Joseph, Jeffrey I

2015-07-01

Hyperglycemia and hypoglycemia are associated with adverse clinical outcomes in intensive care patients. In product development studies at 4 ICUs, the safety and performance of an intravascular continuous glucose monitoring (IV-CGM) system was evaluated in 70 postsurgical patients. The GluCath System (GluMetrics, Inc) used a quenched chemical fluorescence mechanism to optically measure blood glucose when deployed via a radial artery catheter or directly into a peripheral vein. Periodic ultrasound assessed blood flow and thrombus formation. Patient glucose levels were managed according to the standard of care and existing protocols at each site. Reference blood samples were acquired hourly and compared against prospectively calibrated sensor results. In all, 63 arterial sensors and 9 venous sensors were deployed in 70 patients. Arterial sensors did not interfere with invasive blood pressure monitoring, sampling or other aspects of patient care. A majority of venous sensors (66%) exhibited thrombus on ultrasound. In all, 89.4% (1383/1547) of arterial and 72.2% (182/252) of venous measurements met ISO15197:2003 criteria (within 20%), and 72.7% (1124/1547) of arterial and 56.3% (142/252) of venous measurements met CLSI POCT 12-A3 criteria (within 12.5%). The aggregate mean absolute relative difference (MARD) between the sensors and the reference was 9.6% for arterial and 14.2% for venous sensors. The GluCath System exhibited acceptable accuracy when deployed in a radial artery for up to 48 hours in ICU patients after elective cardiac surgery. Accuracy of venous deployment was substantially lower with significant rates of intravascular thrombus observed using ultrasound. © 2015 Diabetes Technology Society.

Vascular characteristics in young women-Effect of extensive endurance training or a sedentary lifestyle.

PubMed

Bjarnegård, N; Länne, T; Cinthio, M; Ekstrand, J; Hedman, K; Nylander, E; Henriksson, J

2018-06-01

To explore whether high-level endurance training in early age has an influence on the arterial wall properties in young women. Forty-seven athletes (ATH) and 52 controls (CTR), all 17-25 years of age, were further divided into runners (RUN), whole-body endurance athletes (WBA), sedentary controls (SC) and normally active controls (AC). Two-dimensional ultrasound scanning of the carotid arteries was conducted to determine local common carotid artery (CCA) geometry and wall distensibility. Pulse waves were recorded with a tonometer to determine regional pulse wave velocity (PWV) and pulse pressure waveform. Carotid-radial PWV was lower in WBA than in RUN (P < .05), indicating higher arterial distensibility along the arm. Mean arterial pressure was lower in ATH than in CTR and in RUN than in WBA (P < .05). Synthesized aortic augmentation index (AI@75) was lower among ATH than among CTR (-12.8 ± 1.6 vs -2.6 ± 1.2%, P < .001) and in WBA than in RUN (-16.4 ± 2.5 vs -10.7 ± 2.0%, P < .05), suggesting a diminished return of reflection waves to the aorta during systole. Carotid-femoral PWV and intima-media thickness (IMT), lumen diameter and radial distensibility of the CCA were similar in ATH and CTR. Elastic artery distensibility and carotid artery IMT are not different in young women with extensive endurance training over several years and in those with sedentary lifestyle. On the other hand, our data suggest that long-term endurance training is associated with potentially favourable peripheral artery adaptation, especially in sports where upper body work is added. This adaptation, if persisting later in life, could contribute to lower cardiovascular risk. © 2018 Scandinavian Physiological Society. Published by John Wiley & Sons Ltd.

Deceleration time of left ventricular outflow tract flow as a simple surrogate marker for central haemodynamics at rest and as well as during exercise.

PubMed

Cho, In-Jeong; Shim, Chi Young; Moon, Sun-Ha; Lee, Hyun-Jin; Hong, Geu-Ru; Chung, Namsik; Ha, Jong-Won

2017-05-01

The shape and duration of left ventricular outflow tract (LVOT) flow has not been applied to assess the central haemodynamics, although LVOT flow is confronted with afterload of arterial system during systole. The aim of this study was to evaluate whether the LVOT flow parameters are related with central systolic blood pressure (BP) and arterial compliance at rest and as well as during exercise. We studied 258 subjects (175 females, age 61 ± 11 years) with normal left ventricular (LV) systolic function who underwent supine bicycle stress echocardiography and arterial tonometry simultaneously at rest and at peak exercise. Deceleration time (DT) of LVOT flow and RR interval were measured and deceleration time corrected for heart rate (DTc) was calculated. Peripheral and central haemodynamic parameters including systolic and diastolic BP, and augmentation index at a heart rate of 75 (AIx@75) were assessed using radial artery tonometry. Carotid femoral pulse wave velocity (PWV) was measured. Deceleration time corrected for heart rate was independently associated with central systolic BP and AIx@75 at rest (P < 0.001 and 0.006). Similarly, it also showed significant independent correlations with central systolic BP and AIx@75 during peak exercise (P = 0.006 and P = 0.021). In addition, DTc which measured both at rest and at peak exercise demonstrated significant positive correlations with PWV, suggesting association of prolonged DTc with arterial stiffening (P = 0.023 and P = 0.005). Prolongation of LVOT flow DTc represents raised central systolic BP and increased arterial stiffness not only at rest but also during exercise. Therefore, central aortic pressures and arterial stiffness influence the DT of LVOT flow at rest as well as during exercise in individuals with normal LV systolic function. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: journals.permissions@oup.com.

Effects of arm elevation on radial artery pressure: a new method to distinguish hypovolemic shock and septic shock from hypotension.

PubMed

Xie, Zhiyi; Zhang, Zhenyu; Xu, Yuan; Zhou, Hua; Wu, Sheng; Wang, Zhong

2018-06-01

In this prospective observational study, we investigated the variability in radial artery invasive blood pressure associated with arm elevation in patients with different hemodynamic types. We carried out a prospective observational study using data from 73 general anesthesia hepatobiliary postoperative adult patients admitted to an ICU over a 1-year period. A standard procedure was used for the arm elevation test. The value of invasive radial arterial pressure was recorded at baseline, and 30 and 60 s after the arm had been raised from 0° to 90°. We compared the blood pressure before versus after arm elevation, and between hemodynamically stable, hypovolemic shock, and septic shock patient groups. In all 73 patients, systolic arterial pressure (SAP) decreased, diastolic arterial pressure (DAP) increased, and pulse pressure (PP) decreased at 30 and 60 s after arm elevation (P<0.01), but the mean arterial pressure (MAP) was unchanged (P>0.05). On comparing 30 and 60 s, there was no significant difference in SAP, DAP, PP, or MAP (P>0.05). In 40 hemodynamically stable patients, SAP and PP decreased, and DAP and MAP increased significantly at 30 and 60 s after arm elevation compared with baseline (P<0.01). In 16 hypovolemic patients, SAP, DAP, and MAP increased significantly compared with baseline at 30 and 60 s (P<0.01), but PP was unchanged (P>0.05). In 17 patients with septic shock, SAP, PP, and MAP decreased significantly versus baseline at 30 and 60 s (P<0.01), but DAP was unchanged (P>0.05). Comparison of the absolute value of pressure change of septic shock patients at 30 s after raising the arm showed that SAP, DAP, and MAP changes were significantly lower compared with those in hypovolemic shock and hemodynamically stable patients (P<0.01). The areas under the receiver operator characteristic curve for predicting septic shock was 0.930 [95% confidence interval (CI): 0.867-0.992, P< 0.001] for change value at 30 s after arm elevation of SAP. The best cut-off point for the SAP change value was -5 mmHg or less, with a sensitivity of 94.12%, a specificity of 80.36%, a positive likelihood ratio of 4.79 (95% CI: 2.8-8.2), and a negative likelihood ratio of 0.073 (95% CI: 0.01-0.5). Our study shows that hypovolemic shock and septic shock patients have significantly different radial artery invasive blood pressure changes in an arm elevation test, which could be applied as a new method to distinguish hypovolemic shock and septic shock from hypotension.

Reduction of scatter radiation during transradial percutaneous coronary angiography: a randomized trial using a lead-free radiation shield.

PubMed

Politi, Luigi; Biondi-Zoccai, Giuseppe; Nocetti, Luca; Costi, Tiziana; Monopoli, Daniel; Rossi, Rosario; Sgura, Fabio; Modena, Maria Grazia; Sangiorgi, Giuseppe M

2012-01-01

Occupational radiation exposure is a growing problem due to the increasing number and complexity of interventional procedures performed. Radial artery access has reduced the number of complications at the price of longer procedure duration. Radpad® scatter protection is a sterile, disposable bismuth-barium radiation shield drape that should be able to decrease the dose of operator radiation during diagnostic and interventional procedures. Such radiation shield has never been tested in a randomized study in humans. Sixty consecutive patients undergoing coronary angiography by radial approach were randomized 1:1 to Radpad use versus no radiation shield protection. The sterile shield was placed around the area of right radial artery sheath insertion and extended medially to the patient trunk. All diagnostic procedures were performed by the same operator to reduce variability in radiation absorption. Radiation exposure was measured blindly using thermoluminescence dosimeters positioned at the operator's chest, left eye, left wrist, and thyroid. Despite similar fluoroscopy time (3.52 ± 2.71 min vs. 3.46 ± 2.77 min, P = 0.898) and total examination dose (50.5 ± 30.7 vs. 45.8 ± 18.0 Gycm(2), P = 0.231), the mean total radiation exposure to the operator was significantly lower when Radpad was utilized (282.8 ± 32.55 μSv vs. 367.8 ± 105.4 μSv, P < 0.0001) corresponding to a 23% total reduction. Moreover, mean radiation exposure was lower with Radpad utilization at all body locations ranging from 13 to 34% reduction. This first-in-men randomized trial demonstrates that Radpad significantly reduces occupational radiation exposure during coronary angiography performed through right radial artery access. Copyright © 2011 Wiley Periodicals, Inc.

Sheathless guide catheter in transradial percutaneous coronary intervention for ST-segment elevation myocardial infarction.

PubMed

Miyasaka, Masaki; Tada, Norio; Kato, Shigeaki; Kami, Masahiro; Horie, Kazunori; Honda, Taku; Takizawa, Kaname; Otomo, Tatsushi; Inoue, Naoto

2016-05-01

The aim of this study was to assess the safety and efficacy of sheathless guide catheters in transradial percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction (STEMI). Transradial PCI for STEMI offers significant clinical benefits, including a reduced incidence of vascular complications. As the size of the radial artery is small, the radial artery is frequently damaged in this procedure using large-bore catheters. A sheathless guide catheter offers a solution to this problem as it does not require an introducer sheath. However, the efficacy and safety of sheathless guide catheters remain to be fully determined in emergent transradial PCI for STEMI. Data on consecutive STEMI patients undergoing primary PCI at the Sendai Kousei Hospital between September 2010 and May 2013 were analyzed. The primary endpoint was the rate of acute procedural success without access site crossover. Secondary endpoints included door-to-balloon time, fluoroscopy time, volume of contrast, and radial artery stenosis or occlusion rate. We conducted transradial PCI for 478 patients with STEMI using a sheathless guide catheter. Acute procedural success was achieved in 466 patients (97.5%). The median door-to-balloon time was 45 min (range, 15-317 min). The median fluoroscopy time was 16.4 min (range, 10-90 min). The median volume of contrast was 134 mL (range, 31-431 mL). Radial stenosis or occlusion developed in 14 (3.8%) of the 370 evaluable patients. This study showed that use of a sheathless guide catheter taking a transradial approach was effective and safe in primary PCI for STEMI. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

In vivo oxygen transport in the normal rabbit femoral arterial wall.

PubMed Central

Crawford, D W; Back, L H; Cole, M A

1980-01-01

In vivo measurements of tissue oxygen tension were made at 10-micrometer intervals through functioning in situ rabbit femoral arterial walls, using inhalation anesthesia and recessed microcathodes with approximately 4-micrometer external diameters. External environment was controlled with a superfusion well at 30 torr PO2, 35 torr PCO2. Blood pressure, gas tension levels, and blood pH were held within the normal range. Radial PO2 measurements closely fit a mathematical model for unidimensional diffusion into a thick-walled artery with uniform oxygen consumption, and the distances traversed fit measured dimensions of quick-frozen in vivo sections. Using standard values of diffusion and solubility coefficients, mean calculated medial oxygen consumption was 99 nl0/ml-s. Mural oxygen consumption appeared to be related linearly to mean tangential wall stress. Differences in experimental design and technique were compared with previous in vivo and in vitro measurements of wall oxygenation, and largely account for the varying results obtained. Control of environment external to the artery, and maintenance of normally flowing blood in the lumen in vivo appeared critical to an understanding of mural oxygenation in life. If the conditions of this experiment prevailed in arteries with thicker avascular layers, PO2 could have been 20 torr at approximately 156 micrometer and 10 torr at 168 micrometer from blood (average values). Images PMID:7410554

Plasma Amino Acid Abnormalities in Chronic Heart Failure. Mechanisms, Potential Risks and Targets in Human Myocardium Metabolism

PubMed Central

Aquilani, Roberto; La Rovere, Maria Teresa; Corbellini, Daniela; Pasini, Evasio; Verri, Manuela; Barbieri, Annalisa; Condino, Anna Maria; Boschi, Federica

2017-01-01

The goal of this study was to measure arterial amino acid levels in patients with chronic heart failure (CHF), and relate them to left ventricular function and disease severity. Amino acids (AAs) play a crucial role for heart protein-energy metabolism. In heart failure, arterial AAs, which are the major determinant of AA uptake by the myocardium, are rarely measured. Forty-one subjects with clinically stable CHF (New York Heart Association (NYHA) class II to IV) were analyzed. After overnight fasting, blood samples from the radial artery were taken to measure AA concentrations. Calorie (KcalI), protein-, fat-, carbohydrate-intake, resting energy expenditure (REE), total daily energy expenditure (REE × 1.3), and cardiac right catheterization variables were all measured. Eight matched controls were compared for all measurements, with the exception of cardiac catheterization. Compared with controls, CHF patients had reduced arterial AA levels, of which both their number and reduced rates are related to Heart Failure (HF) severity. Arterial aspartic acid correlated with stroke volume index (r = 0.6263; p < 0.0001) and cardiac index (r = 0.4243; p = 0.0028). The value of arterial aspartic acid (µmol/L) multiplied by the cardiac index was associated with left ventricular ejection fraction (r = 0.3765; p = 0.0076). All NYHA groups had adequate protein intake (≥1.1 g/kg/day) and inadequate calorie intake (KcalI < REE × 1.3) was found only in class IV patients. This study showed that CHF patients had reduced arterial AA levels directly related to clinical disease severity and left ventricular dysfunction. PMID:29140312

High-resolution ultrasound imaging and noninvasive optoacoustic monitoring of blood variables in peripheral blood vessels

NASA Astrophysics Data System (ADS)

Petrov, Irene Y.; Petrov, Yuriy; Prough, Donald S.; Esenaliev, Rinat O.

2011-03-01

Ultrasound imaging is being widely used in clinics to obtain diagnostic information non-invasively and in real time. A high-resolution ultrasound imaging platform, Vevo (VisualSonics, Inc.) provides in vivo, real-time images with exceptional resolution (up to 30 microns) using high-frequency transducers (up to 80 MHz). Recently, we built optoacoustic systems for probing radial artery and peripheral veins that can be used for noninvasive monitoring of total hemoglobin concentration, oxyhemoglobin saturation, and concentration of important endogenous and exogenous chromophores (such as ICG). In this work we used the high-resolution ultrasound imaging system Vevo 770 for visualization of the radial artery and peripheral veins and acquired corresponding optoacoustic signals from them using the optoacoustic systems. Analysis of the optoacoustic data with a specially developed algorithm allowed for measurement of blood oxygenation in the blood vessels as well as for continuous, real-time monitoring of arterial and venous blood oxygenation. Our results indicate that: 1) the optoacoustic technique (unlike pure optical approaches and other noninvasive techniques) is capable of accurate peripheral venous oxygenation measurement; and 2) peripheral venous oxygenation is dependent on skin temperature and local hemodynamics. Moreover, we performed for the first time (to the best of our knowledge) a comparative study of optoacoustic arterial oximetry and a standard pulse oximeter in humans and demonstrated superior performance of the optoacoustic arterial oximeter, in particular at low blood flow.

Gender-specific association of the plasminogen activator inhibitor-1 4G/5G polymorphism with central arterial blood pressure.

PubMed

Björck, Hanna M; Eriksson, Per; Alehagen, Urban; De Basso, Rachel; Ljungberg, Liza U; Persson, Karin; Dahlström, Ulf; Länne, Toste

2011-07-01

The functional plasminogen activator inhibitor-1 (PAI-1) 4G/5G polymorphism has previously been associated with hypertension. In recent years, central blood pressure, rather than brachial has been argued a better measure of cardiovascular damage and clinical outcome. The aim of this study was to investigate the possible influence of the 4G/5G polymorphism on central arterial blood pressure in a cohort of elderly individuals. We studied 410 individuals, 216 men and 194 women, aged 70-88. Central pressures and pulse waveforms were calculated from the radial artery pressure waveform by the use of the SphygmoCor system and a generalized transfer function. Brachial pressure was recorded using oscillometric technique (Dinamap, Critikon, Tampa, FL). PAI-1 antigen was determined in plasma. The results showed that central pressures were higher in women carrying the PAI-1 4G/4G genotype compared to female carriers of the 5G/5G genotype, (P = 0.025, P = 0.002, and P = 0.002 for central systolic-, diastolic-, and mean arterial pressure, respectively). The association remained after adjustment for potentially confounding factors related to hypertension. No association of the PAI-1 genotype with blood pressure was found in men. Multiple regression analysis revealed an association between PAI-1 genotype and plasma PAI-1 levels (P = 0.048). Our findings show a gender-specific association of the PAI-1 4G/5G polymorphism with central arterial blood pressure. The genotype effect was independent of other risk factors related to hypertension, suggesting that impaired fibrinolytic potential may play an important role in the development of central hypertension in women.

Intravascular Papillary Endothelial Hyperplasia (Masson’s Tumor) of the Radial Artery: A Case Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stark, Christopher, E-mail: Christopher.stark@uvmhealth.org; Olsen, Daniel; Morris, Christopher

Intravascular papillary endothelial hyperplasia (IPEH), often referred to as Masson’s tumor, is a benign non-neoplastic vascular lesion of the skin and subcutaneous tissues. Although it is rare, knowledge of the existence of IPEH is important as it can mimic other benign and malignant tumors, most notably angiosarcoma. IPEH remains an incompletely understood entity; however, most consider it to be the result of reactive endothelial proliferation following thrombus formation within a vessel, vascular malformation, or adjacent to a vessel. In this article, we report a case of IPEH arising within an arteriovenous malformation of the radial artery and present accompanying multimodalitymore » imaging and pathology figures. We will also describe the clinical presentation, pathophysiology, histology, imaging features, and management of IPEH.« less

Single Center Retrospective Analysis of Conventional and Radial TIG Catheters for Transradial Diagnostic Coronary Angiography.

PubMed

Vorpahl, Marc; Koehler, Till; Foerst, Jason; Panagiotopoulos, Spyridon; Schleiting, Heinrich; Koss, Klaus; Ziegler, Gunda; Brinkmann, Hilmar; Seyfarth, Melchior; Tiroch, Klaus

2015-01-01

Current guidelines favor the radial approach for coronary angiography. Therefore, specialty radial diagnostic catheters were designed to engage both coronary arteries with a single device. However, it is unclear if single catheters are superior to conventional catheters. A retrospective analysis was performed of consecutive right radial coronary angiographies to determine catheter use, fluoroscopy time, radiation dosage, and consumption of contrast. Procedures were performed with a single TIG catheter or conventional catheters (CONV). Procedures with coronary artery bypass grafts or ventricular angiographies were excluded. 273 transradial procedures were performed successfully. 95 procedures were performed with CONV and 178 procedures with a TIG. Crossover to additional catheters was higher in TIG (15.2%) compared to CONV (5.3%, p = 0.02). Fluoroscopy time was comparable between CONV and TIG, without crossover (2.2 ± 1.2 min versus 2.3 ± 1.2 min; n.s.), however, greater in the case of crossover for CONV (5.8 ± 0.7) and TIG (7.6 ± 3.0; p = 0.0001). Radiation dosage was similar in CONV and the TIG, without crossover (1419 ± 1075, cGy∗cm(2) versus 1690 ± 1138; n.s.), however, greater for CONV (2374 ± 620) and TIG (3733 ± 2281, p = 0.05) with crossover. Overall, the amount of contrast was greater in TIG (56 ± 13 mL) versus CONV (48 ± 3 mL; p = 0.0003). CONV femoral catheters may be the primary choice for radial approach.

Effectiveness of sublingual nitroglycerin before puncture compared with conventional intra-carterial nitroglycerin in transradial procedures: a randomized trial.

PubMed

Turan, Burak; Daşlı, Tolga; Erkol, Ayhan; Erden, İsmail

2015-01-01

Sublingual (SL) nitroglycerin administered before radial artery puncture can improve cannulation success and decrease the incidence of radial artery spasm (RAS) compared with intra-arterial (IA) nitroglycerin in transradial procedures. Patients undergoing diagnostic transradial angiography were randomized to IA (200 mcg) or SL (400 mcg) nitroglycerin. Primary endpoints were puncture time and puncture attempts. Secondary endpoint was the incidence of RAS. Total of 101 participants (mean age 60±11years, 53% male) were randomized (51 in IA and 50 in SL groups). Puncture time (50 [36-75] vs 50 [35-90] sec), puncture attempts (1.18±0.48 vs 1.20±0.49), multiple punctures (13.7 vs 16.0%) and RAS (19.6 vs 24.0%) were not statistically different between IA vs SL groups respectively. A composite endpoint of all adverse events related to transradial angiography (multiple punctures, RAS, access site crossover, hypotension/bradycardia associated with nitroglycerin and radial artery occlusion) was very similar in IA vs SL groups (39 vs 40%, respectively). However puncture time was significantly longer with SL nitroglycerin in patients <1.65m height (47 [36-66] vs 63 [41-110] sec, p=0.042). Multiple punctures seemed higher with SL nitroglycerin in patients with diabetes (0 vs 30%, p=0.028) or in patients <1.65m height (7.4 vs 25%, p=0.085). Likewise, RAS with SL nitroglycerin seemed more frequent in smokers compared to IA nitroglycerin (0 vs 27%, p=0.089). SL nitroglycerin was not different from IA nitroglycerin in terms of efficiency and safety in overall study population. However it may be inferior to IA nitroglycerin in certain subgroups (shorter individuals, diabetics and smokers). Copyright © 2015 Elsevier Inc. All rights reserved.

[Evaluation and Optimization of Microvascular Arterial Anastomoses by Transit Time Flow Measurement].

PubMed

Herberhold, S; Röttker, J; Bartmann, D; Solbach, A; Keiner, S; Welz, A; Bootz, F; Laffers, W

2016-03-01

INDRODUCTION: The regular application of transit time flow measurement in microvascular anastomoses during heart surgery has lead to improvements of the outcome of coronary artery bypass grafts. Our study was meant to discover whether this measurement method was also applicable for evaluation and optimization of microvascular arterial anastomoses of radial forearm flaps. In this prospective examination a combining ultrasound imaging and transit time flow measurement device (VeriQ, MediStim) was used during surgery to assess anastomotic quality of 15 radial forearm flaps. Pulsatility index (PI) and mean blood flow were measured immediately after opening the arterial anastomosis as well as 15 min afterwards. Furthermore, application time and description of handling were recorded seperately for every assessment. Mean blood flow immediately after opening the anastomosis and 15 min later were 3.9 and 3.4 ml/min resepectively showing no statistically significant difference (p=0.96). There was no significance in the increase of pulsatility index from 22.1 to 27.2 (p=0.09) during the same time range, either. Due to measurement results showing atypical pulse curves in 2 cases decision for surgical revision of the anastomoses was made. All forearm flaps showed good vascularisation during follow-up. Time for device set up, probe placement and measurements was about 20 min. Handling was described to be uncomplicated without exception. There were no noteworthy problems. Transit time flow measurement contributes to the improvement of anastomotic quality and therefore to the overall outcome of radial forearm flaps. The examined measurement method provides objective results and is useful for documentation purposes. © Georg Thieme Verlag KG Stuttgart · New York.

Peroneal perforator-based peroneus longus tendon and sural neurofasciocutaneous composite flap transfer for a large soft-tissue defect of the forearm: A case report.

PubMed

Hayashida, Kenji; Saijo, Hiroto; Fujioka, Masaki

2018-01-01

We describe the use of a composite flap composed of a sural neurofasciocutaneous flap and a vascularized peroneus longus tendon for the reconstruction of severe composite forearm tissue defects in a patient. A 43-year-old man had his left arm caught in a conveyor belt resulting in a large soft-tissue defect of 18 × 11 cm over the dorsum forearm. The extensor carpi radialis, superficial radial nerve, and radial artery were severely damaged. A free neurofasciocutaneous composite flap measuring 16 × 11 cm was outlined on the patient's left lower leg to allow simultaneous skin, tendon, nerve, and artery reconstruction. The flap, which included the peroneus longus tendon, was elevated on the subfascial plane. After the flap was transferred to the recipient site, the peroneal artery was anastomosed to the radial artery in a flow-through manner. The vascularized tendon graft with 15 cm in length was used to reconstruct the extensor carpi radialis longus tendon defect using an interlacing suture technique. As the skin paddle of the sural neurofasciocutaneous flap and the vascularized peroneus longus tendon graft were linked by the perforator and minimal fascial tissue, the skin paddle was able to rotate and slide with comparative ease. The flap survived completely without any complications. The length of follow-up was 12 months and was uneventful. Range of motion of his left wrist joint was slightly limited to 75 degrees. This novel composite flap may be useful for reconstructing long tendon defects associated with extensive forearm soft tissue defects. © 2016 Wiley Periodicals, Inc.

Increased pulse wave transit time after percutaneous coronary intervention procedure in CAD patients.

PubMed

Ji, Lizhen; Liu, Chengyu; Li, Peng; Wang, Xinpei; Liu, Changchun; Hou, Yinglong

2018-01-08

Pulse wave transit time (PWTT) has been widely used as an index in assessing arterial stiffness. Percutaneous coronary intervention (PCI) is usually applied to the treatment of coronary artery disease (CAD). Research on the changes in PWTT caused by PCI is helpful for understanding the impact of the PCI procedure. In addition, effects of stent sites and access sites on the changes in PWTT have not been explored. Consequently, this study aimed to provide this information. The results showed that PWTT significantly increased after PCI (p < 0.01) while the standard deviation (SD) of PWTT time series had no statistically significant changes (p = 0.60) between before and after PCI. Significantly increased PWTT was found in the radial access group (p < 0.01), while there were no significant changes in the femoral access group (p > 0.4). Additionally, PWTT in the left anterior descending (LAD) group significantly increased after PCI (p < 0.01), but the increase that was found in the right coronary artery (RCA) group was not significant (p > 0.1). Our study indicates that arterial elasticity and left ventricular functions can benefit from a successful PCI procedure, and the increase of peripheral PWTT after PCI can help to better understand the effectiveness of the procedure.

Comparison of Arterial Oxygenation Following Head-Down and Head-Up Laparoscopic Surgery.

PubMed

Imani, Farsad; Shirani Amniyeh, Fatemeh; Bastan Hagh, Ehsan; Khajavi, Mohammad Reza; Samimi, Saghar; Yousefshahi, Fardin

2017-12-01

Regarding the role of gas entry in abdomen and cardiorespiratory effects, the ability of anesthesiologists would be challenged in laparoscopic surgeries. Considering few studies in this area and the relevance of the subject, this study was performed to compare the arterial oxygen alterations before operation in comparison with after surgery between laparoscopic cholecystectomy and ovarian cystectomy. In this prospective cohort, 70 consecutive women aged from 20 to 60 years who were candidate for laparoscopic cholecystectomy (n = 35) and ovarian cystectomy (n = 35) with reverse (20 degrees) and direct (30 degrees) Trendelenburg positions, respectively, with ASA class I or II were enrolled. After intubation and before operation, for the first time, the arterial blood gas from radial artery in supine position was obtained for laboratory assessment. Then, the second blood sample was collected from radial artery in supine position and sent to the lab to be assessed with the same device after 30 minutes from surgery termination. The measured variables from arterial blood gas were arterial partial pressure of oxygen (PaO 2 ) and Oxygen saturation (SpO 2 ) alterations. Total PaO 2 was higher in the first measurement. The higher values of PaO 2 in cholecystectomy (upward) than in ovarian cystectomy (downward) were not significant in univariate (P = 0.060) and multivariate analysis (P = 0.654). Furthermore, higher values of SpO 2 in cholecystectomy (upward) than in ovarian cystectomy (downward) were not significant in univariate (P = 0.412) and multivariate analysis (P = 0.984). In general, based on the results of this study, the values of PaO 2 in cholecystectomy (upward) were not significantly higher than the values in cystectomy (downward) in laparoscopic surgeries when measured 30 minutes after surgery.

Comparison of Arterial Oxygenation Following Head-Down and Head-Up Laparoscopic Surgery

PubMed Central

Imani, Farsad; Shirani Amniyeh, Fatemeh; Bastan Hagh, Ehsan; Khajavi, Mohammad Reza; Samimi, Saghar; Yousefshahi, Fardin

2017-01-01

Background Regarding the role of gas entry in abdomen and cardiorespiratory effects, the ability of anesthesiologists would be challenged in laparoscopic surgeries. Considering few studies in this area and the relevance of the subject, this study was performed to compare the arterial oxygen alterations before operation in comparison with after surgery between laparoscopic cholecystectomy and ovarian cystectomy. Methods In this prospective cohort, 70 consecutive women aged from 20 to 60 years who were candidate for laparoscopic cholecystectomy (n = 35) and ovarian cystectomy (n = 35) with reverse (20 degrees) and direct (30 degrees) Trendelenburg positions, respectively, with ASA class I or II were enrolled. After intubation and before operation, for the first time, the arterial blood gas from radial artery in supine position was obtained for laboratory assessment. Then, the second blood sample was collected from radial artery in supine position and sent to the lab to be assessed with the same device after 30 minutes from surgery termination. The measured variables from arterial blood gas were arterial partial pressure of oxygen (PaO2) and Oxygen saturation (SpO2) alterations. Results Total PaO2 was higher in the first measurement. The higher values of PaO2 in cholecystectomy (upward) than in ovarian cystectomy (downward) were not significant in univariate (P = 0.060) and multivariate analysis (P = 0.654). Furthermore, higher values of SpO2 in cholecystectomy (upward) than in ovarian cystectomy (downward) were not significant in univariate (P = 0.412) and multivariate analysis (P = 0.984). Conclusions In general, based on the results of this study, the values of PaO2 in cholecystectomy (upward) were not significantly higher than the values in cystectomy (downward) in laparoscopic surgeries when measured 30 minutes after surgery. PMID:29696125

Influence of Puncture Site on Radial Artery Occlusion After Transradial Coronary Intervention.

PubMed

Bi, Xi-Le; Fu, Xiang-Hua; Gu, Xin-Shun; Wang, Yan-Bo; Li, Wei; Wei, Li-Ye; Fan, Yan-Ming; Bai, Shi-Ru

2016-04-20

The risk of radial artery occlusion (RAO) needs particular attention in transradial intervention (TRI). Therefore, reducing vascular occlusion has an important clinical significance. The aim of this study was to determine the appropriate puncture site during TRI through comparing the occurrence of RAO between the different puncture sites to reduce the occurrence of RAO after TRI. We prospectively assessed the occurrence of RAO in 606 consecutive patients undergoing TRI. Artery occlusion was evaluated with Doppler ultrasound in 2 days and 1 year after the intervention. Risk factors for RAO were evaluated using a multivariate model analysis. Of the 606 patients, the RAO occurred in 56 patients. Compared with TRI at 2-5 cm away from the radius styloid process, the odds ratio (OR) for occlusion risk at 0 cm and 1 cm were 9.65 (P = 0.033) and 8.90 (P = 0.040), respectively. The RAO occurred in the ratio of the arterial diameter to the sheath diameter ≤1 (OR = 2.45, P = 0.004). Distal puncture sites (0-1 cm away from the radius styloid process) can lead to a higher rate of RAO. ClinicalTrials.gov, NCT01979627; https://clinicaltrials.gov/ct2/show/NCT01979627?term = NCT01979627 and rank = 1.

Reevaluation of the superior radial collateral artery in the human upper arm.

PubMed

Ichimura, Koichiro; Kinose, Shota; Kawasaki, Yuto; Kato, Kota; Sakai, Tatsuo

2018-01-01

The superior radial collateral artery (SRCA) was described in well-established anatomy textbooks published in the 1800s. According to those textbooks, the SRCA originates from the brachial artery, passes transversely between the coracobrachialis and the humerus, and distributes to the most distal portion of the deltoid. The SRCA is not listed in the international standard on anatomical terminology, Terminologia Anatomica, or in modern anatomy textbooks. In the present study, we reevaluated the anatomical features of the SRCA by cadaveric dissection. We found that two kinds of SRCAs were consistently present in the upper arm. One was similar to the previous descriptions of the SRCA in terms of origin and course, but the distribution was somewhat different. The other was similar to the previous descriptions in terms of the distribution, although it differed in origin and course. The discrepancy between the description of the SRCA in classical textbooks and the actual morphologies of the SRCA presumably prompted previous anatomists to question the existence of the SRCA, resulting in its absence from anatomical textbooks after a particular time point.

Application of Micropore Filter Technology: Exploring the Blood Flow Path in Arterial-Line Filters and Its Effect on Bubble Trapping Functions

PubMed Central

Herbst, Daniel P.

2017-01-01

Abstract: Conventional arterial-line filters commonly use a large volume circular shaped housing, a wetted micropore screen, and a purge port to trap, separate, and remove gas bubbles from extracorporeal blood flow. Focusing on the bubble trapping function, this work attempts to explore how the filter housing shape and its resulting blood flow path affect the clinical application of arterial-line filters in terms of gross air handling. A video camera was used in a wet-lab setting to record observations made during gross air-bolus injections in three different radially designed filters using a 30–70% glycerol–saline mixture flowing at 4.5 L/min. Two of the filters both had inlet ports attached near the filter-housing top with bottom oriented outlet ports at the bottom, whereas the third filter had its inlet and outlet ports both located at the bottom of the filter housing. The two filters with top-in bottom-out fluid paths were shown to direct the incoming flow downward as it passed through the filter, placing the forces of buoyancy and viscous drag in opposition to each other. This contrasted with the third filter's bottom-in bottom-out fluid path, which was shown to direct the incoming flow upward so that the forces of buoyancy and viscous drag work together. The direction of the blood flow path through a filter may be important to the application of arterial-line filter technology as it helps determine how the forces of buoyancy and flow are aligned with one another. PMID:28298665

Application of Micropore Filter Technology: Exploring the Blood Flow Path in Arterial-Line Filters and Its Effect on Bubble Trapping Functions.

PubMed

Herbst, Daniel P

2017-03-01

Conventional arterial-line filters commonly use a large volume circular shaped housing, a wetted micropore screen, and a purge port to trap, separate, and remove gas bubbles from extracorporeal blood flow. Focusing on the bubble trapping function, this work attempts to explore how the filter housing shape and its resulting blood flow path affect the clinical application of arterial-line filters in terms of gross air handling. A video camera was used in a wet-lab setting to record observations made during gross air-bolus injections in three different radially designed filters using a 30-70% glycerol-saline mixture flowing at 4.5 L/min. Two of the filters both had inlet ports attached near the filter-housing top with bottom oriented outlet ports at the bottom, whereas the third filter had its inlet and outlet ports both located at the bottom of the filter housing. The two filters with top-in bottom-out fluid paths were shown to direct the incoming flow downward as it passed through the filter, placing the forces of buoyancy and viscous drag in opposition to each other. This contrasted with the third filter's bottom-in bottom-out fluid path, which was shown to direct the incoming flow upward so that the forces of buoyancy and viscous drag work together. The direction of the blood flow path through a filter may be important to the application of arterial-line filter technology as it helps determine how the forces of buoyancy and flow are aligned with one another.

Radial optic neurotomy for ischaemic central vein occlusion

PubMed Central

Martínez-Jardón, C S; Meza-de Regil, A; Dalma-Weiszhausz, J; Leizaola-Fernández, C; Morales-Cantón, V; Guerrero-Naranjo, J L; Quiroz-Mercado, H

2005-01-01

Background/aims: Ischaemic central retinal vein occlusion (CRVO) accounts for 20–50% of all CRVO. No treatment has been proved to be effective. The efficacy of radial optic neurotomy (RON) was evaluated in eyes with ischaemic CRVO. Methods: 10 patients with ischaemic CRVO underwent RON. After pars plana vitrectomy, a microvitreoretinal blade was used to incise the scleral ring, cribriform plate, and adjacent sclera at the nasal edge of the optic disc. Best corrected visual acuity (BCVA), intraocular pressure (IOP), fluorescein angiography (FA), multifocal electroretinography (mfERG), and optical coherence tomography (OCT) were measured preoperatively and at 1, 3, and 6 months postoperatively. Results: No visual improvement was noted in the eyes that underwent RON. FA and mfERG showed no increase in retinal perfusion or retinal function postoperatively. Mean macular central thickness changed from 841 (SD 170) μm preoperatively to 162 (SD 34) μm at the sixth postoperative month. One patient had retinal central artery perforation intraoperatively. One patient developed neovascular glaucoma. Conclusion: RON in ischaemic CRVO did not improve visual function (by mfERG) or visual acuity although macular thickness did improve. This technique may be associated with potential risks. Randomised studies are needed to corroborate these results. PMID:15834084

Thymopericardial augmented encasement for coronary artery bypass graft surgery: a report of 245 cases.

PubMed

Ohtsuka, Toshiya; Ninomiya, Mikio; Nonaka, Takahiro

2009-07-01

: A pedicled prepericardial fat flap was created to augment the pericardial cavity and applied for patients undergoing coronary artery bypass grafting. The efficacy and durability of this method were investigated. : Between July 2005 and November 2008, the present technique was applied for consecutive 245 patients (165 men and 80 women, aged 67 ± 8.3 years) undergoing isolated coronary artery bypass grafting in which 240 (98.0%) were off-pump cases. The left and/or right internal thoracic artery and the gastroepiploic artery were used in 244 and 160 patients, respectively, and the saphenous vein and the radial artery were used in 51 and 10 patients, respectively. Ninety-seven (40.0%) patients had been diabetic, 18 (7.3%) had had chronic renal failure, and three were redo cases. The prepericardial soft tissue, involving the pedicled thymic gland, was dissected en bloc and sewn with pericardiotomies to wrap the heart and the grafts. Angiography or three-dimensional computed tomography was used to assess the intrapericardial pathways of each graft and a long-term durability of the fat pad. : Early angiography or three-dimensional computed tomography proved that the graft pathways were unaffected by the encasements. Resternotomies in two patients and sternal treatments for infectious dehiscence in two patients were safely achievable. Five-year postoperative computed tomography showed the intact fat pad in the retrosternal space. : The present technique can encase the heart not the least jeopardizing each pathway of the grafts, and the durable fat pad functions protectively when the sternotomy is either reopened or infected.

Wire-Interwoven Nitinol Stent Outcome in the Superficial Femoral and Proximal Popliteal Arteries: Twelve-Month Results of the SUPERB Trial.

PubMed

Garcia, Lawrence; Jaff, Michael R; Metzger, Christopher; Sedillo, Gino; Pershad, Ashish; Zidar, Frank; Patlola, Raghotham; Wilkins, Robert G; Espinoza, Andrey; Iskander, Ayman; Khammar, George S; Khatib, Yazan; Beasley, Robert; Makam, Satyaprakash; Kovach, Richard; Kamat, Suraj; Leon, Luis R; Eaves, William Britton; Popma, Jeffrey J; Mauri, Laura; Donohoe, Dennis; Base, Carol C; Rosenfield, Kenneth

2015-05-01

Stent-based therapy in the superficial femoral and popliteal arteries in patients with peripheral artery disease is compromised by restenosis and risk of stent fracture or distortion. A novel self-expanding nitinol stent was developed that incorporates an interwoven-wire design (Supera stent, IDEV Technologies, Inc, Webster, TX) to confer greater radial strength, flexibility, and fracture resistance. This prospective, multicenter, investigational device exemption, single-arm trial enrolled 264 patients with symptomatic peripheral artery disease undergoing percutaneous treatment of de novo or restenotic lesions of the superficial femoral or proximal popliteal (femoropopliteal) artery. Freedom from death, target lesion revascularization, or any amputation of the index limb at 30 days (+ 7 days) postprocedure was achieved in 99.2% (258/260) of patients (P < 0.001). Primary patency at 12 months (360 ± 30 days) was achieved in 78.9% (180/228) of the population (P < 0.001). Primary patency by Kaplan-Meier analysis at 12 months (360 days) was 86.3%. No stent fracture was observed by independent core laboratory analysis in the 243 stents (228 patients) evaluated at 12 months. Clinical assessment at 12 months demonstrated improvement by at least 1 Rutherford-Becker category in 88.7% of patients. The SUPERB Trial, an investigational device exemption study using an interwoven nitinol wire stent in the femoropopliteal artery, achieved the efficacy and safety performance goals predesignated by the Food and Drug Administration. On the basis of the high primary patency rate, absence of stent fracture, and significant improvements in functional and quality-of-life measures, the Supera stent provides safe and effective treatment of femoropopliteal lesions in symptomatic patients with peripheral artery disease. URL: http://www.clinicaltrials.gov. Unique identifier: NCT00933270. © 2015 American Heart Association, Inc.

Single Center Retrospective Analysis of Conventional and Radial TIG Catheters for Transradial Diagnostic Coronary Angiography

PubMed Central

Vorpahl, Marc; Koehler, Till; Foerst, Jason; Panagiotopoulos, Spyridon; Schleiting, Heinrich; Koss, Klaus; Ziegler, Gunda; Brinkmann, Hilmar; Seyfarth, Melchior; Tiroch, Klaus

2015-01-01

Current guidelines favor the radial approach for coronary angiography. Therefore, specialty radial diagnostic catheters were designed to engage both coronary arteries with a single device. However, it is unclear if single catheters are superior to conventional catheters. A retrospective analysis was performed of consecutive right radial coronary angiographies to determine catheter use, fluoroscopy time, radiation dosage, and consumption of contrast. Procedures were performed with a single TIG catheter or conventional catheters (CONV). Procedures with coronary artery bypass grafts or ventricular angiographies were excluded. 273 transradial procedures were performed successfully. 95 procedures were performed with CONV and 178 procedures with a TIG. Crossover to additional catheters was higher in TIG (15.2%) compared to CONV (5.3%, p = 0.02). Fluoroscopy time was comparable between CONV and TIG, without crossover (2.2 ± 1.2 min versus 2.3 ± 1.2 min; n.s.), however, greater in the case of crossover for CONV (5.8 ± 0.7) and TIG (7.6 ± 3.0; p = 0.0001). Radiation dosage was similar in CONV and the TIG, without crossover (1419 ± 1075, cGy∗cm2 versus 1690 ± 1138; n.s.), however, greater for CONV (2374 ± 620) and TIG (3733 ± 2281, p = 0.05) with crossover. Overall, the amount of contrast was greater in TIG (56 ± 13 mL) versus CONV (48 ± 3 mL; p = 0.0003). CONV femoral catheters may be the primary choice for radial approach. PMID:26435876

Pulmonary artery imaging under free-breathing using golden-angle radial bSSFP MRI: a proof of concept.

PubMed

Fyrdahl, Alexander; Vargas Paris, Roberto; Nyrén, Sven; Holst, Karen; Ugander, Martin; Lindholm, Peter; Sigfridsson, Andreas

2018-03-14

To evaluate the feasibility of an improved motion and flow robust methodology for imaging the pulmonary vasculature using non-contrast-enhanced, free-breathing, golden-angle radial MRI. Healthy volunteers (n = 10, age 46 ± 11 years, 50% female) and patients (n = 2, ages 27 and 84, both female) were imaged at 1.5 T using a Cartesian and golden-angle radial 2D balanced SSFP pulse sequence. The acquisitions were made under free breathing without contrast agent enhancement. The radial acquisitions were reconstructed at 3 temporal footprints. All series were scored from 1 to 5 for perceived diagnostic quality, artifact level, and vessel sharpness in multiple anatomical locations. In addition, vessel sharpness and blood-to-blood clot contrast were measured. Quantitative measurements showed higher vessel sharpness for golden-angle radial (n = 76, 0.79 ± 0.11 versus 0.71 ± 0.16, p < .05). Blood-to-blood clot contrast was found to be 23% higher in golden-angle radial in the 2 patients. At comparable temporal footprints, golden-angle radial was scored higher for diagnostic quality (mean ± SD, 2.3 ± 0.7 versus 2.2 ± 0.6, p < .01) and vessel sharpness (2.2 ± 0.8 versus 2.1 ± 0.5, p < .01), whereas the artifact level did not differ (3.0 ± 0.9 versus 3.0 ± 1.0, p = .80). The ability to retrospectively choose a temporal resolution and perform sliding-window reconstructions was demonstrated in patients. In pulmonary artery imaging, the motion and flow robustness of a radial trajectory does both improve image quality over Cartesian trajectory in healthy volunteers, and allows for flexible selection of temporal footprints and the ability to perform real-time sliding window reconstructions, which could potentially provide further diagnostic insight. © 2018 International Society for Magnetic Resonance in Medicine.

Occipital-posterior cerebral artery bypass via the occipital interhemispheric approach

PubMed Central

Kazumata, Ken; Yokoyama, Yuka; Sugiyama, Taku; Asaoka, Katsuyuki

2013-01-01

Background: The unavailability of the superficial temporal artery (STA) and the location of lesions pose a more technically demanding challenge when compared with conventional STA-superior cerebellar or posterior cerebral artery (PCA) bypass in vascular reconstruction procedures. To describe a case series of patients with cerebrovascular lesions who were treated using an occipital artery (OA) to PCA bypass via the occipital interhemispheric approach. Methods: We retrospectively reviewed three consecutive cases of patients with cerebrovascular lesions who were treated using OA-PCA bypass. Results: OA-PCA bypass was performed via the occipital interhemispheric approach. This procedure included: (1) OA-PCA bypass (n = 1), and combined OA-posterior inferior cerebellar artery and OA-PCA saphenous vein interposition graft bypass (n = 1) in patients with vertebrobasilar ischemia; (2) OA-PCA radial artery interposition graft bypass in one patient with residual PCA aneurysm. Conclusions: OA-PCA bypass represents a useful alternative to conventional STA-SCA or PCA bypass. PMID:23956933

Preserved cardiorespiratory function and NT-proBNP levels before and during exercise in patients with recent onset of rheumatoid arthritis: the clinical challenge of stratifying the patient cardiovascular risks.

PubMed

Zoli, A; Bosello, S; Comerci, G; Galiano, N; Forni, A; Loperfido, F; Ferraccioli, G F

2017-01-01

Rheumatoid arthritis (RA) is associated with an increased risk of myocardial infarction and congestive heart failure. In RA patients, elevated NT-proBNP levels have been reported to be a prognostic marker of left ventricular dysfunction. In this study, we evaluated cardiorespiratory functional capacity and NT-proBNP levels before and during cardiopulmonary exercise test in early RA (ERA) patients. Twenty ERA patients and 10 healthy controls were studied by color Doppler echocardiography to evaluate ventricular systolic and diastolic function. Arterial stiffness and wave reflections were quantified non-invasively using applanation tonometry of the radial artery. Cardiopulmonary treadmill test was performed to measure peak VO 2 and VE/VCO 2 parameters. NT-proBNP plasma levels were measured before and at the exercise peak during cardiopulmonary exercise. The peak oxygen uptake [VO 2 (ml/min/kg)], the ventilatory equivalents for carbon dioxide (EqCO 2 ), respiratory exchange ratio and arterial stiffness were similar between patients and controls during cardiopulmonary exercise test. Basal and peak cardiopulmonary exercise NT-proBNP plasma levels were comparable in ERA patients with respect to healthy controls. When we analyzed patients according to disease characteristics and cardiovascular risk factors, ERA patients with high disease activity, BMI > 25 kg/m 2 and ACPA positivity presented significantly higher baseline and exercise peak NT-proBNP levels. Cardiorespiratory function is preserved in patients with recent onset of rheumatoid arthritis. The increased basal and exercise peak NT-proBNP plasma levels in patients with negative disease prognostic factors represent a possible marker to stratify the cardiovascular risk in patients with early rheumatoid arthritis.

Evidence-based Comprehensive Approach to Forearm Arterial Laceration

PubMed Central

Thai, Janice N.; Pacheco, Jose A.; Margolis, David S.; Swartz, Tianyi; Massey, Brandon Z.; Guisto, John A.; Smith, Jordan L.; Sheppard, Joseph E.

2015-01-01

Introduction Penetrating injury to the forearm may cause an isolated radial or ulnar artery injury, or a complex injury involving other structures including veins, tendons and nerves. The management of forearm laceration with arterial injury involves both operative and nonoperative strategies. An evolution in management has emerged especially at urban trauma centers, where the multidisciplinary resource of trauma and hand subspecialties may invoke controversy pertaining to the optimal management of such injuries. The objective of this review was to provide an evidence-based, systematic, operative and nonoperative approach to the management of isolated and complex forearm lacerations. A comprehensive search of MedLine, Cochrane Library, Embase and the National Guideline Clearinghouse did not yield evidence-based management guidelines for forearm arterial laceration injury. No professional or societal consensus guidelines or best practice guidelines exist to our knowledge. Discussion The optimal methods for achieving hemostasis are by a combination approach utilizing direct digital pressure, temporary tourniquet pressure, compressive dressings followed by wound closure. While surgical hemostasis may provide an expedited route for control of hemorrhage, this aggressive approach is often not needed (with a few exceptions) to achieve hemostasis for most forearm lacerations. Conservative methods mentioned above will attain the same result. Further, routine emergent or urgent operative exploration of forearm laceration injuries are not warranted and not cost-beneficial. It has been widely accepted with ample evidence in the literature that neither injury to forearm artery, nerve or tendon requires immediate surgical repair. Attention should be directed instead to control of bleeding, and perform a complete physical examination of the hand to document the presence or absence of other associated injuries. Critical ischemia will require expeditious surgical restoration of arterial perfusion. In a well-perfused hand, however, the presence of one intact artery is adequate to sustain viability without long-term functional disability, provided the palmar arch circulation is intact. Early consultation with a hand specialist should be pursued, and follow-up arrangement made for delayed primary repair in cases of complex injury. Conclusion Management in accordance with well-established clinical principles will maximize treatment efficacy and functional outcome while minimizing the cost of medical care. PMID:26759666

Continuous blood pressure monitoring via non-invasive radial artery applanation tonometry and invasive arterial catheter demonstrates good agreement in patients undergoing colon carcinoma surgery.

PubMed

Sun, Jing; Chen, Hanjian; Zheng, Jun; Mao, Bin; Zhu, Shengmei; Feng, Jingyi

2017-12-01

Radial artery applanation tonometry (RAAT) has been developed and utilized for continuous arterial pressure monitoring. However, evidence is lacking to clinically verify the RAAT technology and identify appropriate patient groups before routine clinical use. This study aims to evaluate the RAAT technology by comparing systolic blood pressure (SBP), mean blood pressure (MBP) and diastolic blood pressure (DBP) values in patients undergoing colon carcinoma surgery. Blood Pressure (BP) values obtained via RAAT (TL-300, Tensys Medical Inc., San Diego, CA, USA) and conventional arterial catheterization from 30 colon carcinoma surgical patients were collected and compared via Bland-Atman method, linear regression and 4-quadrant plot concordance analysis. For SBPs, MBPs and DBPs, means of the differences (±standard deviation; 95% limits of agreement) were -0.9 (±7.6; -15.7 to 13.9) mmHg, 3.1 (±6.5; -9.6 to 15.8) mmHg and 4.3 (±7.4; -10.3 to 18.8) mmHg, respectively. Linear regression coefficients of determination were 0.8706 for SBPs, 0.8353 for MBPs and 0.6858 for DBPs. Four-quadrant concordance correlation coefficients were 0.8740, 0.8522 and 0.7108 for SBPs, MBPs and DBPs, respectively. A highly selected patient collective undergoing colon carcinoma surgery was studied. BP measurements obtained via the TL-300 had clinically acceptable agreement with that acquired invasively using an arterial catheter. For use in clinical routine, it is necessary to take measures for improvement regarding movement artifacts and dilution of noise. A large sample size of patients under various conditions is also needed to further evaluate the RAAT technology before clinically routine use.

Intrapericardial denervation - Radial artery blood flow and heart rate responses to LBNP

NASA Technical Reports Server (NTRS)

Mckeever, Kenneth H.; Skidmore, Michael G.; Keil, Lanny C.; Sandler, Harold

1990-01-01

The effects of intrapericardial denervation on the radial artery blood flow velocity (RABFV) and heart rate (HR) responses to LBNP in rhesus monkeys were investigated by measuring the RABFV transcutaneously by a continuous-wave Doppler ultrasonic flowmeter in order to derive an index of forearm blood flow response to low (0 to -20 mm Hg) and high (0 to -60 mm Hg) ramp exposures during supine LBNP. Four of the eight subjects were subjected to efferent and afferent cardiac denervation. It was found that, during low levels of LBNP, monkeys with cardiac denervation exhibited no cardiopulmonary baroreceptor-mediated change in the RABFV or HR, unlike the intact animals, which showed steady decreases in RABFV during both high- and low-pressure protocols. It is suggested that forearm blood flow and HR responses to low-level LBNP, along with pharmacological challenge, are viable physiological tests for verifying the completeness of atrial and cardiopulmonary baroreceptor denervation.

A viscoelastic fluid-structure interaction model for carotid arteries under pulsatile flow.

PubMed

Wang, Zhongjie; Wood, Nigel B; Xu, Xiao Yun

2015-05-01

In this study, a fluid-structure interaction model (FSI) incorporating viscoelastic wall behaviour is developed and applied to an idealized model of the carotid artery under pulsatile flow. The shear and bulk moduli of the arterial wall are described by Prony series, where the parameters can be derived from in vivo measurements. The aim is to develop a fully coupled FSI model that can be applied to realistic arterial geometries with normal or pathological viscoelastic wall behaviour. Comparisons between the numerical and analytical solutions for wall displacements demonstrate that the coupled model is capable of predicting the viscoelastic behaviour of carotid arteries. Comparisons are also made between the solid only and FSI viscoelastic models, and the results suggest that the difference in radial displacement between the two models is negligible. Copyright © 2015 John Wiley & Sons, Ltd.

Intraoperative left subclavian artery occlusion with left hand ischaemia and steal syndrome in the left internal thoracic artery

PubMed Central

Jelenc, Matija; Kneževič, Ivan; Stankovič, Milenko; Geršak, Borut

2012-01-01

We present a case of a 62-year old man with a left main stenosis, left coronary artery dominance, normal ejection fraction and no valvular pathology, and status post right carotid artery stenting, who was scheduled for elective coronary revascularization. We performed off-pump coronary revascularization, anastomosing the left internal thoracic artery to the left anterior descending artery, and three separate saphenous vein grafts to the intermediate artery and the first and second obtuse marginals, respectively. Proximally, the right internal thoracic artery was used as the inflow for all three venous grafts due to a heavily calcified ascending aorta. During the construction of the distal anastomoses to the obtuse marginals, the arterial pressure in the left radial artery suddenly dropped. The left hand was found to be pale and pulseless. A femoral artery catheter was placed for pressure monitoring and the anastomoses were completed as planned. Intraoperative transit-time graft flow measurement showed a reversed flow in the left internal thoracic artery. Postoperatively, angiography was performed showing a subtotal stenosis of the proximal left subclavian artery. The artery was dilated and stented. The postoperative course was uneventful and the patient was discharged on the 12th postoperative day. PMID:22767542

Principles of cerebral hemodynamics when intracranial pressure is raised: lessons from the peripheral circulation

PubMed Central

Kim, Mi Ok; Adji, Audrey; O’Rourke, Michael F.; Avolio, Alberto P.; Smielewski, Peter; Pickard, John D.; Czosnyka, Marek

2015-01-01

Background: The brain is highly vascular and richly perfused, and dependent on continuous flow for normal function. Although confined within the skull, pressure within the brain is usually less than 15 mmHg, and shows small pulsations related to arterial pulse under normal circumstances. Pulsatile arterial hemodynamics in the brain have been studied before, but are still inadequately understood, especially during changes of intracranial pressure (ICP) after head injury. Method: In seeking cohesive explanations, we measured ICP and radial artery pressure (RAP) invasively with high-fidelity manometer systems, together with middle cerebral artery flow velocity (MCAFV) (transcranial Doppler) and central aortic pressure (CAP) generated from RAP, using a generalized transfer function technique, in eight young unconscious, ventilated adults following closed head trauma. We focused on vascular effects of spontaneous rises of ICP (‘plateau waves’). Results: A rise in mean ICP from 29 to 53 mmHg caused no consistent change in pressure outside the cranium, or in heart rate, but ICP pulsations increased in amplitude from 8 to 20 mmHg, and ICP waveform came to resemble that in the aorta. Cerebral perfusion pressure (=central aortic pressure – ICP), which equates with transmural pressure, fell from 61 to 36 mmHg. Mean MCAFV fell from 53 to 40 cm/s, whereas pulsatile MCAFV increased from 77 to 98 cm/s. These significant changes (all P < 0.01) may be explained using the Monro–Kellie doctrine, because of compression of the brain, as occurs in a limb when external pressure is applied. Conclusion: The findings emphasize importance of reducing ICP, when raised, and on the additional benefits of reducing wave reflection from the lower body. PMID:25764046

In-line positioning of ultrasound images using wireless remote display system with tablet computer facilitates ultrasound-guided radial artery catheterization.

PubMed

Tsuchiya, Masahiko; Mizutani, Koh; Funai, Yusuke; Nakamoto, Tatsuo

2016-02-01

Ultrasound-guided procedures may be easier to perform when the operator's eye axis, needle puncture site, and ultrasound image display form a straight line in the puncture direction. However, such methods have not been well tested in clinical settings because that arrangement is often impossible due to limited space in the operating room. We developed a wireless remote display system for ultrasound devices using a tablet computer (iPad Mini), which allows easy display of images at nearly any location chosen by the operator. We hypothesized that the in-line layout of ultrasound images provided by this system would allow for secure and quick catheterization of the radial artery. We enrolled first-year medical interns (n = 20) who had no prior experience with ultrasound-guided radial artery catheterization to perform that using a short-axis out-of-plane approach with two different methods. With the conventional method, only the ultrasound machine placed at the side of the head of the patient across the targeted forearm was utilized. With the tablet method, the ultrasound images were displayed on an iPad Mini positioned on the arm in alignment with the operator's eye axis and needle puncture direction. The success rate and time required for catheterization were compared between the two methods. Success rate was significantly higher (100 vs. 70 %, P = 0.02) and catheterization time significantly shorter (28.5 ± 7.5 vs. 68.2 ± 14.3 s, P < 0.001) with the tablet method as compared to the conventional method. An ergonomic straight arrangement of the image display is crucial for successful and quick completion of ultrasound-guided arterial catheterization. The present remote display system is a practical method for providing such an arrangement.

Self-excited multi-scale skin vibrations probed by optical tracking micro-motions of tracers on arms

NASA Astrophysics Data System (ADS)

Chen, Wei-Chia; Chen, Hsiang-Ying; Chen, Yu-Sheng; Tian, Yong; I, Lin

2017-07-01

The self-excited multi-scale mechanical vibrations, their sources and their mutual coupling of different regions on the forearms of supine subjects, are experimentally investigated, using a simple noncontact method, optical video microscopy, which provides 1 μm and 25 ms spatiotemporal resolutions. It is found that, in proximal regions far from the radial artery, the vibrations are the global vibrations of the entire forearm excited by remote sources, propagating through the trunk and the limb. The spectrum is mainly composed of peaks of very low frequency motion (down to 0.05 Hz), low frequency respiration modes, and heartbeat induced modes (about 1 Hz and its harmonics), standing out of the spectrum floor exhibiting power law decay. The nonlinear mode-mode coupling leads to the cascaded modulations of higher frequency modes by lower frequency modes. The nearly identical waveforms without detectable phase delays for a pair of signals along or transverse to the meridian of regions far away from the artery rule out the detectable contribution from the propagation of Qi, some kind of collective excitation which more efficiently propagates along meridians, according to the Chinese medicine theory. Around the radial artery, in addition to the global vibration, the local vibration spectrum shows very slow breathing type vibration around 0.05 Hz, and the artery pulsation induced fundamental and higher harmonics with descending intensities up to the fifth harmonics, standing out of a flat spectrum floor. All the artery pulsation modes are also modulated by respiration and the very slow vibration.

Placental Glucose Transfer: A Human In Vivo Study

PubMed Central

Holme, Ane M.; Roland, Marie Cecilie P.; Lorentzen, Bjørg; Michelsen, Trond M.; Henriksen, Tore

2015-01-01

Objectives The placental transfer of nutrients is influenced by maternal metabolic state, placenta function and fetal demands. Human in vivo studies of this interplay are scarce and challenging. We aimed to establish a method to study placental nutrient transfer in humans. Focusing on glucose, we tested a hypothesis that maternal glucose concentrations and uteroplacental arterio-venous difference (reflecting maternal supply) determines the fetal venous-arterial glucose difference (reflecting fetal consumption). Methods Cross-sectional in vivo study of 40 healthy women with uncomplicated term pregnancies undergoing planned caesarean section. Glucose and insulin were measured in plasma from maternal and fetal sides of the placenta, at the incoming (radial artery and umbilical vein) and outgoing vessels (uterine vein and umbilical artery). Results There were significant mean (SD) uteroplacental arterio-venous 0.29 (0.23) mmol/L and fetal venous-arterial 0.38 (0.31) mmol/L glucose differences. The transplacental maternal-fetal glucose gradient was 1.22 (0.42) mmol/L. The maternal arterial glucose concentration was correlated to the fetal venous glucose concentration (r = 0.86, p<0.001), but not to the fetal venous-arterial glucose difference. The uteroplacental arterio-venous glucose difference was neither correlated to the level of glucose in the umbilical vein, nor fetal venous-arterial glucose difference. The maternal-fetal gradient was correlated to fetal venous-arterial glucose difference (r = 0.8, p<0.001) and the glucose concentration in the umbilical artery (r = −0.45, p = 0.004). Glucose and insulin concentrations were correlated in the mother (r = 0.52, p = 0.001), but not significantly in the fetus. We found no significant correlation between maternal and fetal insulin values. Conclusions We did not find a relation between indicators of maternal glucose supply and the fetal venous-arterial glucose difference. Our findings indicate that the maternal-fetal glucose gradient is significantly influenced by the fetal venous-arterial difference and not merely dependent on maternal glucose concentration or the arterio-venous difference on the maternal side of the placenta. PMID:25680194

Embedding a randomized clinical trial into an ongoing registry infrastructure: unique opportunities for efficiency in design of the Study of Access site For Enhancement of Percutaneous Coronary Intervention for Women (SAFE-PCI for Women).

PubMed

Hess, Connie N; Rao, Sunil V; Kong, David F; Aberle, Laura H; Anstrom, Kevin J; Gibson, C Michael; Gilchrist, Ian C; Jacobs, Alice K; Jolly, Sanjit S; Mehran, Roxana; Messenger, John C; Newby, L Kristin; Waksman, Ron; Krucoff, Mitchell W

2013-09-01

Women are at higher risk than men for bleeding and vascular complications after percutaneous coronary intervention (PCI). Compared with femoral access, radial access reduces these complications but may be more challenging in women because of higher rates of radial artery spasm, tortuosity, and occlusion as well as lower rates of procedure success. Whether the safety advantages of radial versus femoral access in women undergoing PCI are outweighed by reduced effectiveness has not been studied. The Study of Access site For Enhancement of PCI for Women is a prospective, randomized clinical trial comparing radial with femoral arterial access in women undergoing PCI. In conjunction with the US Food and Drug Administration's Critical Path Cardiac Safety Research Consortium, this study embeds the randomized clinical trial into the existing infrastructure of the National Cardiovascular Data Registry CathPCI Registry through the National Institute of Health's National Cardiovascular Research Infrastructure. The primary efficacy end point is a composite of bleeding (Bleeding Academic Research Consortium types 2, 3, or 5) or vascular complication requiring intervention occurring at 72 hours after PCI or by hospital discharge. The primary feasibility end point is procedure success. Secondary end points include procedure duration, contrast volume, radiation dose, quality of life, and a composite of 30-day death, vascular complication, or unplanned revascularization. © 2013.

Similar Outcomes in Diabetes Patients After Coronary Artery Bypass Grafting With Single Internal Thoracic Artery Plus Radial Artery Grafting and Bilateral Internal Thoracic Artery Grafting.

PubMed

Raza, Sajjad; Blackstone, Eugene H; Houghtaling, Penny L; Koprivanac, Marijan; Ravichandren, Kirthi; Javadikasgari, Hoda; Bakaeen, Faisal G; Svensson, Lars G; Sabik, Joseph F

2017-12-01

The purpose of this study was to determine in patients with diabetes mellitus whether single internal thoracic artery (SITA) plus radial artery (RA) grafting yields outcomes similar to those of bilateral internal thoracic artery (BITA) grafting. From January 1994 to January 2011, 1,325 diabetic patients underwent primary isolated coronary artery bypass graft surgery with either (1) SITA plus RA with or without saphenous vein (SV) grafts (n = 965) or (2) BITA with or without SV grafts (n = 360); an internal thoracic artery was used in all patients to graft the left anterior descending coronary artery. Endpoints were in-hospital outcomes and time-related mortality. Median follow-up was 7.4 years, with a total follow-up of 9,162 patient-years. Propensity score matching was performed to identify 282 well-matched pairs for adjusted comparisons. Unadjusted in-hospital mortality was 0.52% for SITA plus RA with or without SV grafts and 0.28% for BITA with or without SV grafts, and prevalence of deep sternal wound infection was 3.2% and 1.7%, respectively. Unadjusted survival at 1, 5, 10, and 14 years was 97%, 88%, 68%, and 51% for SITA plus RA with or without SV grafts, and 97%, 95%, 80%, and 66% for BITA with or without SV grafts, respectively. Among propensity-matched patients, in-hospital mortality (0.35% versus 0.35%) and prevalence of deep sternal wound infection (1.4% versus 1.4%) were similar (p > 0.9) in the two groups, as was 1-, 5-, 10-, and 14-year survival: 97%, 90%, 70%, and 58% for SITA plus RA with or without SV grafting versus 97%, 93%, 79%, and 64% for BITA with or without SV grafting, respectively (early p = 0.8, late p = 0.2). For diabetic patients, SITA plus RA with or without SV grafting and BITA with or without SV grafting yield similar in-hospital outcomes and long-term survival after coronary artery bypass graft surgery. Therefore, both SITA plus RA and BITA plus SV grafting should be considered for these patients. Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

Blunt traumatic axillary artery truncation, in the absence of associated fracture.

PubMed

Bokser, Emily; Caputo, William; Hahn, Barry; Greenstein, Josh

2018-02-01

Axillary artery injuries can be associated with both proximal humeral fractures (Naouli et al., 2016; Ng et al., 2016) [1,2] as well as shoulder dislocations (Leclerc et al., 2017; Karnes et al., 2016) [3,4]. We report a rare case of an isolated axillary artery truncation following blunt trauma without any associated fracture or dislocation. A 58-year-old male presented to the emergency department for evaluation after falling on his outstretched right arm. The patient was found to have an absent right radial pulse with decreased sensation to the right arm. Point of care ultrasound showed findings suspicious for traumatic axillary artery injury, and X-rays did not demonstrate any fracture. Computed tomography with angiography confirmed axillary artery truncation with active extravasation. The patient underwent successful vascular repair with an axillary artery bypass. Although extremity injuries are common in emergency departments, emergency physicians need to recognize the risk for vascular injuries, even without associated fracture or dislocation. Copyright © 2017 Elsevier Inc. All rights reserved.

Radial extracorporeal shock wave therapy improves cerebral blood flow and neurological function in a rat model of cerebral ischemia.

PubMed

Kang, Nan; Zhang, Jing; Yu, Xiaotong; Ma, Yuewen

2017-01-01

We performed middle cerebral artery occlusion (MCAO) in rats to investigate the effect and some of the underlying mechanisms of radial extracorporeal shock wave therapy (rESWT) in cerebral ischemia rats. We measured neurological function and cerebral blood flow (CBF) using a full-field laser perfusion imager and brain infarct volume on days 3, 12, and 30. Immunofluorescence, western blot, and real-time polymerase chain reaction (PCR) techniques were used to detect the expression of vascular endothelial growth factor (VEGF), neuron-specific enolase (NSE), nestin, Wnt3a, and β-catenin in the ischemic hemisphere. The dose of rESWT used on the head revealed remarkable advantages over sham rESWT, as demonstrated by improved neurological function scores, increased CBF, and reduced brain infarct volume. Furthermore, applying rESWT to the head and limbs enhanced short-term neurological function. Our results confirmed that rESWT can induce VEGF expression over an extended period with a profound effect, which may be the primary reason for CBF recovery. High NSE and nestin expression levels suggest that rESWT enhanced the number of neurons and neural stem cells (NSCs). Wnt3a and β-catenin expression were up-regulated in the ischemic hemisphere, indicating that rESWT promoted NSC proliferation and differentiation via the Wnt/β-catenin pathway. Overall, our findings suggest that an appropriate rESWT dose delivered to the head of rats helps restore neurological function and CBF, and additional application of rESWT to the limbs is more effective than treating the head alone.

Meshless Local Petrov-Galerkin Euler-Bernoulli Beam Problems: A Radial Basis Function Approach

NASA Technical Reports Server (NTRS)

Raju, I. S.; Phillips, D. R.; Krishnamurthy, T.

2003-01-01

A radial basis function implementation of the meshless local Petrov-Galerkin (MLPG) method is presented to study Euler-Bernoulli beam problems. Radial basis functions, rather than generalized moving least squares (GMLS) interpolations, are used to develop the trial functions. This choice yields a computationally simpler method as fewer matrix inversions and multiplications are required than when GMLS interpolations are used. Test functions are chosen as simple weight functions as in the conventional MLPG method. Compactly and noncompactly supported radial basis functions are considered. The non-compactly supported cubic radial basis function is found to perform very well. Results obtained from the radial basis MLPG method are comparable to those obtained using the conventional MLPG method for mixed boundary value problems and problems with discontinuous loading conditions.

Unusual pattern of the first dorsal metacarpal artery.

PubMed

Bianchi, Homero; Saravia, Diego; Ottone, Nicolas Ernesto

2017-07-01

This report describes an unusual pattern of the first dorsal metacarpal artery (FDMA) regarding its course and termination. This FDMA had an abnormal course, passing deep to various anatomical elements related to the index finger, with unusual termination in the radial and ulnar proper palmar digital arteries feeding the second and third fingers, respectively. There is no mention of this anatomical variation in the literature. We report the possible embryological origin of this case and other variations related to the FDMA. This unusual pattern represents a new reason to consider anatomical knowledge important for surgeons whose procedures are in this area and to ensure an accurate diagnosis and safe treatment of pathologies that might engage this anatomical variation.

Access site-related complications after transradial catheterization can be reduced with smaller sheath size and statins.

PubMed

Honda, Tsuyoshi; Fujimoto, Kazuteru; Miyao, Yuji; Koga, Hidenobu; Hirata, Yoshihiro

2012-09-01

The aim of this study was to investigate the risk factors for access site-related complications after transradial coronary angiography (CAG) or percutaneous coronary intervention (PCI). Transradial PCI has been shown to reduce access site-related bleeding complications compared with procedures performed through a femoral approach. Although previous studies focused on risk factors for access site-related complications after a transfemoral approach or transfemoral and transradial approaches, it is uncertain which factors affect vascular complications after transradial catheterization. We enrolled 500 consecutive patients who underwent transradial CAG or PCI. We determined the incidence and risk factors for access site-related complications such as radial artery occlusion and bleeding complications. Age, sheath size, the dose of heparin and the frequency of PCI (vs. CAG) were significantly greater in patients with than without bleeding complications. However, body mass index (BMI) was significantly lower in patients with than without bleeding complications. Sheath size was significantly higher and the frequency of statin use was significantly lower in patients with than without radial artery occlusion. Multiple logistic analysis revealed that sheath size [odds ratio (OR) 5.5; P < 0.05] and BMI (OR 0.86; P < 0.01) were risk factors for bleeding complications; and sheath size (OR 5.2; P < 0.05) and the lack of statin pretreatment (OR 0.50; P < 0.05) were risk factors for occlusive complications. In conclusion, these findings indicate that down-sizing of the devices used in transradial procedures might attenuate access site-related complications after transradial CAG or PCI. Statin pretreatment might also be a strategy that could prevent radial artery occlusion after transradial procedures.

Respiratory variation of systolic and diastolic time intervals within radial arterial waveform: a comparison with dynamic preload index.

PubMed

Park, Ji Hyun; Hwang, Gyu-Sam

2016-08-01

A blood pressure (BP) waveform contains various pieces of information related to respiratory variation. Systolic time interval (STI) reflects myocardial performance, and diastolic time interval (DTI) represents diastolic filling. This study examined whether respiratory variations of STI and DTI within radial arterial waveform are comparable to dynamic indices. During liver transplantation, digitally recorded BP waveform and stroke volume variation (SVV) were retrospectively analyzed. Beat-to-beat STI and DTI were extracted within each BP waveform, which were separated by dicrotic notch. Systolic time variation (STV) was calculated by the average of 3 consecutive respiratory cycles: [(STImax- STImin)/STImean]. Similar formula was used for diastolic time variation (DTV) and pulse pressure variation (PPV). Receiver operating characteristic analysis with area under the curve (AUC) was used to assess thresholds predictive of SVV ≥12% and PPV ≥12%. STV and DTV showed significant correlations with SVV (r= 0.78 and r= 0.67, respectively) and PPV (r= 0.69 and r= 0.69, respectively). Receiver operating characteristic curves demonstrated that STV ≥11% identified to predict SVV ≥12% with 85.7% sensitivity and 89.3% specificity (AUC = 0.935; P< .001). DTV ≥11% identified to predict SVV ≥12% with 71.4% sensitivity and 85.7% specificity (AUC = 0.829; P< .001). STV ≥12% and DTV ≥11% identified to predict PPV ≥12% with an AUC of 0.881 and 0.885, respectively. Respiratory variations of STI and DTI derived from radial arterial contour have a potential to predict hemodynamic response as a surrogate for SVV or PPV. Copyright © 2016 Elsevier Inc. All rights reserved.

Transradial Approach for Transcatheter Selective Superior Mesenteric Artery Urokinase Infusion Therapy in Patients with Acute Extensive Portal and Superior Mesenteric Vein Thrombosis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang Maoqiang, E-mail: wangmq@vip.sina.com; Guo Liping; Lin Hanying

2010-02-15

The purpose of this investigation was to assess the feasibility and effectiveness of transradial approach for transcatheter superior mesenteric artery (SMA) urokinase infusion therapy in patients with acute extensive portal and superior mesenteric venous thrombosis. During a period of 7 years, 16 patients with acute extensive thrombosis of the portal (PV) and superior mesenteric veins (SMV) were treated by transcatheter selective SMA urokinase infusion therapy by way of the radial artery. The mean age of the patients was 39.5 years. Through the radial sheath, a 5F Cobra catheter was inserted into the SMA, and continuous infusion of urokinase was performedmore » for 5-11 days (7.1 {+-} 2.5 days). Adequate anticoagulation was given during treatment, throughout hospitalization, and after discharge. Technical success was achieved in all 16 patients. Substantial clinical improvement was seen in these 16 patients after the procedure. Minor complications at the radial puncture site were observed in 5 patients, but trans-SMA infusion therapy was not interrupted. Follow-up computed tomography scan before discharge demonstrated nearly complete disappearance of PV-SMV thrombosis in 9 patients and partial recanalization of PV-SMV thrombosis in 7 patients. The 16 patients were discharged 9-19 days (12 {+-} 6.0 days) after admission. Mean duration of follow-up after hospital discharge was 44 {+-} 18.5 months, and no recurrent episodes of PV-SMV thrombosis developed during that time period. Transradial approach for transcatheter selective SMA urokinase infusion therapy in addition to anticoagulation is a safe and effective therapy for the management of patients with acute extensive PV-SMV thrombosis.« less

Forearm and hand arteries’ aneurysms – a case report of bilateral true ulnar artery aneurysm in the hypothenar eminence and systematic review of the literature.

PubMed

De Santis, F; Martini, G; Mani, G; Zywica, M; Zipponi, D

2013-06-01

Arterial aneurysms in the forearm, wrist and hand are relatively uncommon. Penetrating injuries, arterial traumas, infections and repetitive microtraumas represent the most frequent cause of these secondary aneurysms or pseudo-aneurysms, while true nontraumaticor infective peripheral aneurysms of the upper extremities are very rarely encountered. Over the last 20 years these have been reported only sporadically, both in adults and children. We describe a case of bilateral true idiopathic saccular artery aneurysms in the hypothenar eminence, treated with excision and arterial continuity restoration by primary end-to-end anastomosis on the left side and conservatively on the right. To our knowledge, no other similar case has been documented to date. Starting from this original case we conducted a systematic review of the literature via PubMed search on peripheral aneurysms of the forearm and hand arteries from 1933 to the present, including specifically true distal ulnar and radial artery aneurysms. Etiology, clinical characteristics and management of these rare pathological entities are extensively discussed.

Micromorphology of Skeletonized and Pedicled Internal Thoracic and Radial Arteries.

PubMed

Mamchur, Sergey; Bokhan, Nikita; Vecherskii, Yuri; Malyshenko, Egor

2015-01-01

The objective of the study was to estimate the internal thoracic arteries (ITA) and radial arteries (RA) micromorphologic features by light microscopy after harvesting them using the skeletonization and pedicled methods in patients undergoing coronary artery bypass grafting. The micromorphologic characteristics of ITA and RA were studied by luminous microscopy in 61 patients undergoing coronary artery bypass grafting. A total of 122 ITA and RA segments harvested during surgery, fixed in formalin, and stained with hematoxiline and eosin were evaluated. The mean intima-media thickness of ITA was 9.2 and 134.7 µm and that of RA was 9.1 and 334.2 µm, respectively. In the distal segment of ITA the media-intima relation was 1.5 times bigger than in the proximal segment. None of ITA specimens contained atherosclerotic plaques or lipid inclusions. Atherosclerotic plaques were found in 3 (5%) RA specimens. Other degenerative changes were detected in 30%-74.2% of the specimens: splitting of internal elastic lamina, reduced tortuosity of the internal elastic lamina, and thickening and detachment of the intima; their incidence was associated with the skeletonization of the vessels. In conclusion, the incidence of ITA and RA degenerative changes varies from 30%-74.2% and its increase is associated with the skeletonization of the vessels, which is statistically significant. The media of the RA is 2.5 times thicker than that of the ITA (P < 0.01). This fact shows that RA has higher spasmogenic potential than that of ITA. The distal segment of the ITA has 1.5 times bigger media-intima relation than the proximal segment. Therefore, in case of enough graft length, it is recommended to avoid the distal segment and cut it off. Copyright © 2015 Elsevier Inc. All rights reserved.

Combined Direct and Indirect Cerebral Revascularization Using Local and Flow-Through Flaps.

PubMed

Azadgoli, Beina; Leland, Hyuma A; Wolfswinkel, Erik M; Bakhsheshian, Joshua; Russin, Jonathan J; Carey, Joseph N

2018-02-01

 Extracranial-intracranial bypass is indicated in ischemic disease such as moyamoya, certain intracranial aneurysms, and other complex neurovascular diseases. In this article, we present our series of local and flow-through flaps for cerebral revascularization as an additional tool to provide direct and indirect revascularization and/or soft tissue coverage.  A retrospective review of a prospectively maintained database was performed identifying nine patients. Ten direct arterial bypass procedures with nine indirect revascularization and/or soft tissue reconstruction were performed.  Indications for arterial bypass included intracranial aneurysm ( n  = 2) and moyamoya disease ( n  = 8). Indications for soft tissue transfer included infected cranioplasty (one) and indirect cerebral revascularization (eight). Four flow-through flaps and five pedicled flaps were used including a flow-through radial forearm fasciocutaneous flap (one), flow-through radial forearm fascial flaps (three), and pedicled temporoparietal fascial (TPF) flaps with distal end anastomosis (five). The superficial temporal vessels (seven) and facial vessels (two) were used as the vascular inflow. Arterial bypass was established into the middle cerebral artery (six) and anterior communicating artery (three). There were no intraoperative complications. All flaps survived with no donor-site complications. In one case of flow-through TPF flap, the direct graft failed, but the indirect flap remained vascularized.  Local and flow-through flaps can improve combined direct and indirect revascularization and provide soft tissue reconstruction. Minimal morbidity has been encountered in early outcomes though long-term results remain under investigation for these combined neurosurgery and plastic surgery procedures.  The level of evidence is IV. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Comparative effect of ace inhibition and angiotensin II type 1 receptor antagonism on bioavailability of nitric oxide in patients with coronary artery disease: role of superoxide dismutase.

PubMed

Hornig, B; Landmesser, U; Kohler, C; Ahlersmann, D; Spiekermann, S; Christoph, A; Tatge, H; Drexler, H

2001-02-13

Flow-dependent, endothelium-mediated vasodilation (FDD) and activity of extracellular superoxide dismutase (EC-SOD), the major antioxidative enzyme of the arterial wall, are severely impaired in patients with coronary artery disease (CAD). We hypothesized that both ACE inhibitor (ACEI) and angiotensin II type 1 receptor antagonist (AT(1)-A) increase bioavailability of nitric oxide (NO) by reducing oxidative stress in the vessel wall, possibly by increasing EC-SOD activity. Thirty-five patients with CAD were randomized to 4 weeks of ACEI (ramipril 10 mg/d) or AT(1)-A (losartan 100 mg/d). FDD of the radial artery was determined by high-resolution ultrasound before and after intra-arterial N-monomethyl-L-arginine (L-NMMA) to inhibit NO synthase and before and after intra-arterial vitamin C to determine the portion of FDD inhibited by oxygen free radicals. EC-SOD activity was determined after release from endothelium by heparin bolus injection. FDD was improved after ramipril and losartan (each group P<0.01), and in particular, the portion of FDD mediated by NO, ie, inhibited by L-NMMA, was increased by >75% (each group P<0.01). Vitamin C improved FDD initially, an effect that was lost after ramipril or losartan. After therapy, EC-SOD activity was increased by >200% in both groups (ACEI, 14.4+/-1.1 versus 3.8+/-0.9 and AT(1)-A, 13.5+/-1.0 versus 3.9+/-0.9 U. mL(-1). min(-1); each P<0.01). CONCLUSIONS-Four weeks of therapy with ramipril or losartan improves endothelial function to similar extents in patients with CAD by increasing the bioavailability of NO. Our results suggest that beneficial long-term effects of interference with the renin-angiotensin system may be related to reduction of oxidative stress within the arterial wall, mediated in part by increased EC-SOD activity.

A simplified measurement of pulse wave velocity is not inferior to standard measurement in young adults and children.

PubMed

Edgell, Heather; Stickland, Michael K; MacLean, Joanna E

2016-06-01

The standard measurement of pulse wave velocity (PWV) is restricted by the need for simultaneous tonometry measurements requiring two technicians and expensive equipment, limiting this technique to well-resourced settings. In this preliminary study, we compared a simplified method of pulse wave detection from the finger and toe to pulse wave detection from the carotid and radial arteries using applanation tonometry in children and young adults. We hypothesized that the simplified method of PWV measurement would strongly correlate with the standard measurement in different age groups and oxygen conditions. Participants included (a) boys and girls aged 8-12 years and (b) men and women aged 18-40 years. Participants rested supine while carotid and radial artery pulse waves were measured using applanation tonometry and finger and toe pulse waves were simultaneously collected using a Finometer Midi and a piezo-electric pulse transducer, respectively. These measurements were repeated under hypoxic conditions. Finger-toe PWV measurements were strongly correlated to carotid-radial PWV in adults (R=0.58; P=0.011), but not in children (R=0.056; P=0.610). Finger-toe PWV was sensitive enough to show increases in PWV with age (P<0.0001) and hypoxia in children (P<0.0001) and adults (P=0.003). These results indicate that the simplified measurement of finger-toe PWV strongly correlates with the standard measurement of carotid-radial PWV in adults, but not in children. However, finger-toe PWV can be used in either population to determine changes with hypoxia.

Arterial puncture using insulin needle is less painful than with standard needle: a randomized crossover study.

PubMed

Ibrahim, Irwani; Yau, Ying Wei; Ong, Lizhen; Chan, Yiong Huak; Kuan, Win Sen

2015-03-01

Arterial punctures are important procedures performed by emergency physicians in the assessment of ill patients. However, arterial punctures are painful and can create anxiety and needle phobia in patients. The pain score of radial arterial punctures were compared between the insulin needle and the standard 23-gauge hypodermic needle. In a randomized controlled crossover design, healthy volunteers were recruited to undergo bilateral radial arterial punctures. They were assigned to receive either the insulin or the standard needle as the first puncture, using blocked randomization. The primary outcome was the pain score measured on a 100-mm visual analogue scale (VAS) for pain, and secondary outcomes were rate of hemolysis, mean potassium values, and procedural complications immediately and 24 hours postprocedure. Fifty healthy volunteers were included in the study. The mean (±standard deviation) VAS score in punctures with the insulin needle was lower than the standard needle (23 ± 22 mm vs. 39 ± 24 mm; mean difference = -15 mm; 95% confidence interval = -22 mm to -7 mm; p < 0.001). The rates of hemolysis and mean potassium value were greater in samples obtained using the insulin needle compared to the standard needle (31.3% vs. 11.6%, p = 0.035; and 4.6 ±0.7 mmol/L vs. 4.2 ±0.5 mmol/L, p = 0.002). Procedural complications were lower in punctures with the insulin needle both immediately postprocedure (0% vs. 24%; p < 0.001) and at 24 hours postprocedure (5.4% vs. 34.2%; p = 0.007). Arterial punctures using insulin needles cause less pain and fewer procedural complications compared to standard needles. However, due to the higher rate of hemolysis, its use should be limited to conditions that do not require a concurrent potassium value in the same blood sample. © 2015 by the Society for Academic Emergency Medicine.

Degree of bioresorbable vascular scaffold expansion modulates loss of essential function.

PubMed

Ferdous, Jahid; Kolachalama, Vijaya B; Kolandaivelu, Kumaran; Shazly, Tarek

2015-10-01

Drug-eluting bioresorbable vascular scaffolds (BVSs) have the potential to restore lumen patency, enable recovery of the native vascular environment, and circumvent late complications associated with permanent endovascular devices. To ensure therapeutic effects persist for sufficient times prior to scaffold resorption and resultant functional loss, many factors dictating BVS performance must be identified, characterized and optimized. While some factors relate to BVS design and manufacturing, others depend on device deployment and intrinsic vascular properties. Importantly, these factors interact and cannot be considered in isolation. The objective of this study is to quantify the extent to which degree of radial expansion modulates BVS performance, specifically in the context of modifying device erosion kinetics and evolution of structural mechanics and local drug elution. We systematically varied degree of radial expansion in model BVS constructs composed of poly dl-lactide-glycolide and generated in vitro metrics of device microstructure, degradation, erosion, mechanics and drug release. Experimental data permitted development of computational models that predicted transient concentrations of scaffold-derived soluble species and drug in the arterial wall, thus enabling speculation on the short- and long-term effects of differential expansion. We demonstrate that degree of expansion significantly affects scaffold properties critical to functionality, underscoring its relevance in BVS design and optimization. Bioresorbable vascular scaffold (BVS) therapy is beginning to transform the treatment of obstructive artery disease, owing to effective treatment of short term vessel closure while avoiding long term consequences such as in situ, late stent thrombosis - a fatal event associated with permanent implants such as drug-eluting stents. As device scaffolding and drug elution are temporary for BVS, the notion of using this therapy in lieu of existing, clinically approved devices seems attractive. However, there is still a limited understanding regarding the optimal lifetime and performance characteristics of erodible endovascular implants. Several engineering criteria must be met and clinical endpoints confirmed to ensure these devices are both safe and effective. In this manuscript, we sought to establish general principles for the design and deployment of erodible, drug-eluting endovascular scaffolds, with focus on how differential expansion can modulate device performance. Copyright © 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

The Application of Elliptic Cylindrical Phantom in Brachytherapy Dosimetric Study of HDR 192Ir Source

NASA Astrophysics Data System (ADS)

Ahn, Woo Sang; Park, Sung Ho; Jung, Sang Hoon; Choi, Wonsik; Do Ahn, Seung; Shin, Seong Soo

2014-06-01

The purpose of this study is to determine the radial dose function of HDR 192Ir source based on Monte Carlo simulation using elliptic cylindrical phantom, similar to realistic shape of pelvis, in brachytherapy dosimetric study. The elliptic phantom size and shape was determined by analysis of dimensions of pelvis on CT images of 20 patients treated with brachytherapy for cervical cancer. The radial dose function obtained using the elliptic cylindrical water phantom was compared with radial dose functions for different spherical phantom sizes, including the Williamsion's data loaded into conventional planning system. The differences in the radial dose function for the different spherical water phantoms increase with radial distance, r, and the largest differences in the radial dose function appear for the smallest phantom size. The radial dose function of the elliptic cylindrical phantom significantly decreased with radial distance in the vertical direction due to different scatter condition in comparison with the Williamson's data. Considering doses to ICRU rectum and bladder points, doses to reference points can be underestimated up to 1-2% at the distance from 3 to 6 cm. The radial dose function in this study could be used as realistic data for calculating the brachytherapy dosimetry for cervical cancer.

Accuracy of continuous noninvasive arterial pressure monitoring in living-liver donors during transplantation.

PubMed

Araz, Coskun; Zeyneloglu, Pinar; Pirat, Arash; Veziroglu, Nukhet; Camkiran Firat, Aynur; Arslan, Gulnaz

2015-04-01

Hemodynamic monitoring is vital during liver transplant surgeries because distinct hemodynamic changes are expected. The continuous noninvasive arterial pressure (CNAP) monitor is a noninvasive device for continuous arterial pressure measurement by a tonometric method. This study compared continuous noninvasive arterial pressure monitoring with invasive direct arterial pressure monitoring in living-liver donors during transplant. There were 40 patients analyzed while undergoing hepatic lobectomy for liver transplant. Invasive pressure monitoring was established at the radial artery and continuous noninvasive arterial pressure monitoring using a finger sensor was recorded simultaneously from the contralateral arm. Systolic, diastolic, and mean arterial pressures from the 2 methods were compared. Correlation between the 2 methods was calculated. A total of 5433 simultaneous measurements were obtained. For systolic arterial blood pressure, 55% continuous noninvasive arterial pressure measurements were within 10% direct arterial measurement; the correlation was 0.479, continuous noninvasive arterial pressure bias was -0.3 mm Hg, and limits of agreement were 32.0 mm Hg. For diastolic arterial blood pressure, 50% continuous noninvasive arterial pressure measurements were within 10% direct arterial measurement; the correlation was 0.630, continuous noninvasive arterial pressure bias was -0.4 mm Hg, and limits of agreement were 21.1 mm Hg. For mean arterial blood pressure, 60% continuous noninvasive arterial pressure measurements were within 10% direct arterial measurement; the correlation was 0.692, continuous noninvasive arterial pressure bias was +0.4 mm Hg, and limits of agreement were 20.8 mm Hg. The 2 monitoring techniques did not show acceptable agreement. Our results suggest that continuous noninvasive arterial pressure monitoring is not equivalent to invasive arterial pressure monitoring in donors during living-donor liver transplant.

Five-Year Clinical Outcome of Endoscopic Versus Open Radial Artery Harvesting: A Propensity Score Analysis.

PubMed

Bisleri, Gianluigi; Giroletti, Laura; Hrapkowicz, Tomasz; Bertuletti, Martina; Zembala, Marian; Arieti, Mario; Muneretto, Claudio

2016-10-01

Despite the popularity of less invasive approaches for conduits procurement in coronary artery bypass graft surgery, concerns have been raised about the potential detrimental effects of the endoscopic technique when compared with the conventional "open" technique. Among 470 patients undergoing coronary surgery with the use of a radial artery conduit, a propensity score analysis was performed among those patients assigned either to an open technique (n = 82) or to an endoscopic approach (n = 82). Endoscopic harvesting was performed with a nonsealed system. The primary endpoint was cardiac-related mortality, and secondary endpoint was survival free from major cardiac and cerebrovascular adverse events. Moreover, hand and forearm sensory discomfort and forearm wound healing were also assessed. No conversion to the open technique occurred in patients undergoing endoscopic harvesting. No patients in either group showed hand ischemia; wound infection occurred only in the open group (open 7.3% versus endoscopic 0%, p = 0.007). Wound healing (Hollander scale) was considerably better in the endoscopic group (open 3.3, endoscopic 4.7; p < 0.001) as well as paresthesia at the latest follow-up (open 19.5% versus endoscopic 3.6%, p < 0.001). Pain (visual analog scale score) was significantly reduced with the endoscopic technique (open 3.2, endoscopic 1.2; p = 0.003). At 5 years of follow-up, freedom from cardiac-related mortality (open 96.3% ± 2.1% versus endoscopic 98.1% ± 1.8%; p = 0.448) as well as survival free from major cardiac and cerebrovascular adverse events (open 93.9% ± 2.6% versus endoscopic 93% ± 3.4%; p = 0.996) were similar among the groups. Endoscopic radial artery harvesting allows for incremental benefits in the short term in terms of improved cosmesis and reduced wound and neurologic complications, without yielding detrimental effects in terms of graft-related events at 5 years of follow-up. Copyright © 2016 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

A Cubic Radial Basis Function in the MLPG Method for Beam Problems

NASA Technical Reports Server (NTRS)

Raju, I. S.; Phillips, D. R.

2002-01-01

A non-compactly supported cubic radial basis function implementation of the MLPG method for beam problems is presented. The evaluation of the derivatives of the shape functions obtained from the radial basis function interpolation is much simpler than the evaluation of the moving least squares shape function derivatives. The radial basis MLPG yields results as accurate or better than those obtained by the conventional MLPG method for problems with discontinuous and other complex loading conditions.

Radial Artery as a Coronary Artery Bypass Conduit: 20-Year Results.

PubMed

Gaudino, Mario; Tondi, Paolo; Benedetto, Umberto; Milazzo, Valentina; Flore, Roberto; Glieca, Franco; Ponziani, Francesca Romana; Luciani, Nicola; Girardi, Leonard N; Crea, Filippo; Massetti, Massimo

2016-08-09

There is a lack of evidence for the choice of the second conduit in coronary surgery. The radial artery (RA) is a possible option, but few data on very-long-term outcomes exist. This study describes 20-year results of RA grafts used for coronary artery bypass grafting and the effects of RA removal on forearm circulation. We report the results of the prospective 20-year follow-up of the first 100 consecutive patients who received the RA as a coronary bypass conduit at our institution. Follow-up was 100% complete. There were 64 deaths, 23 (35.9%) from cardiovascular causes. Kaplan-Meier 20-year survival was 31%. Of the 36 survivors, 33 (91.6%) underwent RA graft control at a mean of 19.0 ± 2.5 years after surgery. The RA was found to be patent in 24 cases (84.8% patency). In the overall population, probability of graft failure at 20 years was 19.0 ± 0.2% for the left internal thoracic artery (ITA), 25.0 ± 0.2% for the RA, and 55.0 ± 0.2% for the saphenous vein (p = 0.002 for RA vs. saphenous vein, 0.11 for RA vs. ITA, and p < 0.001 for ITA vs. saphenous vein). Target vessel stenosis >90%, but not location of distal anastomosis, significantly influenced long-term RA graft patency. No patients reported hand or forearm symptoms. The ulnar artery diameter was increased in the operated arm (2.44 ± 0.43 mm vs. 2.01 ± 0.47 mm; p < 0.05) and correlated with the peak systolic velocity of the second palmar digital artery (Pearson coefficient: 0.621; p < 0.05). The 20-year patency rate of RA grafts is good, and not inferior to the ITA, especially when the conduit is used to graft a vessel with >90% stenosis. RA harvesting does not lead to hand or forearm symptoms, even at a very-long-term follow-up. Copyright © 2016 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Temporal changes in radial access use, associates and outcomes in patients undergoing PCI using rotational atherectomy between 2007 and 2014: results from the British Cardiovascular Intervention Society national database.

PubMed

Kinnaird, Tim; Cockburn, James; Gallagher, Sean; Choudhury, Anirban; Sirker, Alex; Ludman, Peter; de Belder, Mark; Copt, Samuel; Mamas, Mamas; de Belder, Adam

2018-04-01

Access site choice for cases requiring rotational atherectomy (PCI-ROTA) is poorly defined. Using the British Cardiovascular Intervention Society PCI database, temporal changes and contemporary associates/outcomes of access site choice for PCI-ROTA were studied. Data were analysed from 11,444 PCI-ROTA procedures performed in England and Wales between 2007 and 2014. Multivariate logistic regression was used to identify predictors of access site choice and its association with outcomes. For PCI-ROTA, radial access increased from 19.6% in 2007 to 58.6% in 2014. Adoption of radial access was slower in females, those with prior CABG, and in patients with chronic occlusive (CTO) or left main disease. In 2013/14, the strongest predictors of femoral artery use were age (OR 1.02, [1.005-1.036], P = .008), CTO intervention (OR 1.95, [1.209-3.314], P = .006), and history of previous CABG (OR 1.68, [1.124-2.515], P = .010). Radial access was associated with reductions in overall length of stay, and increased rates of same-day discharge. Procedural success rates were similar although femoral access use was associated with increased access site complications (2.4 vs. 0.1%, P < .001). After adjustment for baseline differences, arterial complications (OR 15.6, P < .001), transfusion (OR 12.5, P = .023) and major bleeding OR 6.0, P < .001) remained more common with FA use. Adjusted mortality and MACE rates were similar in both groups. In contemporary practice, radial access for PCI-ROTA results in similar procedural success when compared to femoral access but is associated with shorter length of stay, and lower rates of vascular complication, major bleeding and transfusion. Copyright © 2018 Elsevier Inc. All rights reserved.

Assessing photoplethysmographic imaging performance beyond facial perfusion analysis

NASA Astrophysics Data System (ADS)

Amelard, Robert; Hughson, Richard L.; Greaves, Danielle K.; Clausi, David A.; Wong, Alexander

2017-02-01

Photoplethysmographic imaging (PPGI) systems are relatively new non-contact biophotonic diffuse reflectance systems able to assess arterial pulsations through transient changes in light-tissue interaction. Many PPGI studies have focused on extracting heart rate from the face or hand. Though PPGI systems can be used for widefield imaging of any anatomical area, whole-body investigations are lacking. Here, using a novel PPGI system, coded hemodynamic imaging (CHI), we explored and analyzed the pulsatility at major arterial locations across the whole body, including the neck (carotid artery), arm/wrist (brachial, radial and ulnar arteries), and leg/feet (popliteal and tibial arteries). CHI was positioned 1.5 m from the participant, and diffuse reactance from a broadband tungsten-halogen illumination was filtered using 850{1000 nm bandpass filter for deep tissue penetration. Images were acquired over a highly varying 24-participant sample (11/13 female/male, age 28.7+/-12.4 years, BMI 25.5+/-5.2 kg/m2), and a preliminary case study was performed. B-mode ultrasound images were acquired to validate observations through planar arterial characteristics.

Auxetic coronary stent endoprosthesis: fabrication and structural analysis.

PubMed

Amin, Faisal; Ali, Murtaza Najabat; Ansari, Umar; Mir, Mariam; Minhas, Muhammad Asim; Shahid, Wakeel

2015-07-04

Cardiovascular heart disease is one of the leading health issues in the present era and requires considerable health care resources to prevent it. The present study was focused on the development of a new coronary stent based on novel auxetic geometry which enables the stent to exhibit a negative Poisson's ratio. Commercially available coronary stents have isotropic properties, whereas the vascular system of the body shows anisotropic characteristics. This results in a mismatch between anisotropic-isotropic properties of the stent and arterial wall, and this in turn is not favorable for mechanical adhesion of the commercially available coronary stents with the arterial wall. It is believed that an auxetic coronary stent with inherent anisotropic mechanical properties and negative Poisson's ratio will have good mechanical adhesion with the arterial wall. The auxetic design was obtained via laser cutting, and surface treatment was performed with acid pickling and electropolishing, followed by an annealing process. In vitro mechanical analysis was performed to analyze the mechanical performance of the auxetic coronary stent. Scanning electronic microscopy (SEM) was used to determine the effects of fabrication processes on the topography of the auxetic stent. The elastic recoil (3.3%) of the in vitro mechanical analysis showed that the auxetic stent design effectively maintained the luminal patency of the coronary artery. Also, the auxetic coronary stent showed no foreshortening, therefore it avoids the problem of stent migration, by expanding in both the radial and longitudinal directions. By virtue of its synclastic behavior, the auxetic stent bulges outward when it is radially expanded through an inflated balloon.

A database of virtual healthy subjects to assess the accuracy of foot-to-foot pulse wave velocities for estimation of aortic stiffness.

PubMed

Willemet, Marie; Chowienczyk, Phil; Alastruey, Jordi

2015-08-15

While central (carotid-femoral) foot-to-foot pulse wave velocity (PWV) is considered to be the gold standard for the estimation of aortic arterial stiffness, peripheral foot-to-foot PWV (brachial-ankle, femoral-ankle, and carotid-radial) are being studied as substitutes of this central measurement. We present a novel methodology to assess theoretically these computed indexes and the hemodynamics mechanisms relating them. We created a database of 3,325 virtual healthy adult subjects using a validated one-dimensional model of the arterial hemodynamics, with cardiac and arterial parameters varied within physiological healthy ranges. For each virtual subject, foot-to-foot PWV was computed from numerical pressure waveforms at the same locations where clinical measurements are commonly taken. Our numerical results confirm clinical observations: 1) carotid-femoral PWV is a good indicator of aortic stiffness and correlates well with aortic PWV; 2) brachial-ankle PWV overestimates aortic PWV and is related to the stiffness and geometry of both elastic and muscular arteries; and 3) muscular PWV (carotid-radial, femoral-ankle) does not capture the stiffening of the aorta and should therefore not be used as a surrogate for aortic stiffness. In addition, our analysis highlights that the foot-to-foot PWV algorithm is sensitive to the presence of reflected waves in late diastole, which introduce errors in the PWV estimates. In this study, we have created a database of virtual healthy subjects, which can be used to assess theoretically the efficiency of physiological indexes based on pulse wave analysis. Copyright © 2015 the American Physiological Society.

A database of virtual healthy subjects to assess the accuracy of foot-to-foot pulse wave velocities for estimation of aortic stiffness

PubMed Central

Chowienczyk, Phil; Alastruey, Jordi

2015-01-01

While central (carotid-femoral) foot-to-foot pulse wave velocity (PWV) is considered to be the gold standard for the estimation of aortic arterial stiffness, peripheral foot-to-foot PWV (brachial-ankle, femoral-ankle, and carotid-radial) are being studied as substitutes of this central measurement. We present a novel methodology to assess theoretically these computed indexes and the hemodynamics mechanisms relating them. We created a database of 3,325 virtual healthy adult subjects using a validated one-dimensional model of the arterial hemodynamics, with cardiac and arterial parameters varied within physiological healthy ranges. For each virtual subject, foot-to-foot PWV was computed from numerical pressure waveforms at the same locations where clinical measurements are commonly taken. Our numerical results confirm clinical observations: 1) carotid-femoral PWV is a good indicator of aortic stiffness and correlates well with aortic PWV; 2) brachial-ankle PWV overestimates aortic PWV and is related to the stiffness and geometry of both elastic and muscular arteries; and 3) muscular PWV (carotid-radial, femoral-ankle) does not capture the stiffening of the aorta and should therefore not be used as a surrogate for aortic stiffness. In addition, our analysis highlights that the foot-to-foot PWV algorithm is sensitive to the presence of reflected waves in late diastole, which introduce errors in the PWV estimates. In this study, we have created a database of virtual healthy subjects, which can be used to assess theoretically the efficiency of physiological indexes based on pulse wave analysis. PMID:26055792

Impact of calibration on estimates of central blood pressures.

PubMed

Soender, T K; Van Bortel, L M; Møller, J E; Lambrechtsen, J; Hangaard, J; Egstrup, K

2012-12-01

Using the Sphygmocor device it is recommended that the radial pressure wave is calibrated for brachial systolic blood pressure (SBP) and diastolic blood pressure (DBP). However it has been suggested that brachial-to-radial pressure amplification causes underestimation of central blood pressures (BPs) using this calibration. In the present study we examined if different calibrations had an impact on estimates of central BPs and on the clinical interpretation of our results. On the basis of ambulatory BP measurements, patients were categorized into patients with controlled, uncontrolled or resistant hypertension. We first calibrated the radial pressure wave as recommended and afterwards recalibrated the same pressure wave using brachial DBP and calculated mean arterial pressure. Recalibration of the pressure wave generated significantly higher estimates of central SBP (P=0.0003 and P<0.0001 at baseline and P=0.0001 and P=0.0002 after 6 months). Using recommended calibration we found a significant change in central SBP in both treatment groups (P=0.05 and P=0.01), however, after recalibrating significance was lost in patients with resistant hypertension (P=0.15). We conclude that calibration with DBP and mean arterial pressure produces higher estimates of central BPs than recommended calibration. The present study also shows that this difference between the two calibration methods can produce more than a systematic error and has an impact on interpretation of clinical results.

Hemodynamic changes during displacement of the beating heart using epicardial stabilization for off-pump coronary artery bypass graft surgery.

PubMed

Mishra, Manisha; Malhotra, Rajneesh; Mishra, Anil; Meharwal, Zile Singh; Trehan, Naresh

2002-12-01

To evaluate the hemodynamic alterations during off-pump coronary artery bypass graft surgery to determine the degree of impairment caused and the techniques to rectify them. Prospective, observational cohort study performed from January 2000 through September 2000. Patients (n = 500) with coronary artery disease undergoing multivessel off-pump coronary artery bypass graft surgery using the Octopus tissue stabilizer (Medtronic, Inc, Minneapolis, MN). Unstable patients with ongoing ischemia were excluded from the study. All patients were monitored with radial artery and pulmonary artery catheters and continuous transesophageal echocardiography monitoring with a multiplane transducer. The perioperative requirement of an intracoronary shunt, inotropes, or an intra-aortic balloon pump was noted. The effect of the Trendelenburg position and fluids on hemodynamics was observed. The need for defibrillation and institution of emergency cardiopulmonary bypass were major endpoints to determine the inability of the patient to tolerate displacement of the heart. Mean patient age was 59.3 +/- 11.6 years. There were 204 (40%) patients in the high-risk category; 54 (10.8%) patients had left ventricular ejection fraction <25%. The mean number of grafts was 2.7 +/- 0.8. Vertical displacement of the heart to access the lateral and inferior walls decreased the mean arterial pressure by 18 +/- 4% (p < 0.01), with a concomitant increase in central venous pressure of 66 +/- 18% (p < 0.001). The stroke volume and the cardiac index were reduced by 35.7 +/- 11% (p < 0.001) and 45 +/- 13% (p < 0.001). On transesophageal echocardiography, there was development of new regional wall motion abnormalities in 59.2% and a decrease in global left ventricular functions in 61.2%. The use of inotropes was highest during anastomosis on the posterior wall-78.4% compared with 21.9% for the anterior wall. An intra-aortic balloon pump was used in 55 (11.2%) patients, and 7 (0.71 %) patients had to be put on emergency CPB. The in-hospital mortality was 1.2%. Most patients had hemodynamic changes easily correctable by fluids and inotropes. Monitoring of left ventricular and right ventricular function by transesophageal echocardiography enhances safety of the procedure and is recommended. The use of the Octopus II tissue stabilizer proved to be a safe and versatile means to stabilize the heart during off-pump coronary artery bypass procedures, especially in high-risk patients. Copyright 2002, Elsevier Science (USA). All rights reserved.

An anatomic description of intrinsic brachial muscles in the crab-eating fox (Cerdocyon thous, Linnaeus 1776) and report of a variant arterial distribution.

PubMed

Vélez, J; Ramírez, J; Aristizábal, O

2018-04-01

The crab-eating fox (Cerdocyon thous) is a wild canid distributed throughout South America. It is one of the wild canids reported being hit by vehicles and injured in snares, thus inducing trauma or injury to the musculoskeletal system, possibly occurring in the brachial region. The main objective of this research was to provide an anatomic description of the crab-eating fox's intrinsic brachial muscles including shape, origin, insertion, innervation and arterial blood supply, compared with that of the domestic dog. We dissected from superficial to deep two thoracic limbs of seven dead specimens donated to the University of Caldas by CORPOCALDAS. These muscles presented anatomic characteristics similar to those reported in the domestic dog (Canis lupus familiaris) but with a variant in arterial blood supply, allowing us to suggest that surgical procedures that need the knowledge of intrinsic brachial muscles in the crab-eating fox may be homologous to the domestic dog. However, one should consider its variant arterial distribution by part of the collateral radial artery and deep brachial artery to prevent incorrect incisions that may damage these arteries. © 2017 Blackwell Verlag GmbH.

Motion Tracking of the Carotid Artery Wall From Ultrasound Image Sequences: a Nonlinear State-Space Approach.

PubMed

Gao, Zhifan; Li, Yanjie; Sun, Yuanyuan; Yang, Jiayuan; Xiong, Huahua; Zhang, Heye; Liu, Xin; Wu, Wanqing; Liang, Dong; Li, Shuo

2018-01-01

The motion of the common carotid artery (CCA) wall has been established to be useful in early diagnosis of atherosclerotic disease. However, tracking the CCA wall motion from ultrasound images remains a challenging task. In this paper, a nonlinear state-space approach has been developed to track CCA wall motion from ultrasound sequences. In this approach, a nonlinear state-space equation with a time-variant control signal was constructed from a mathematical model of the dynamics of the CCA wall. Then, the unscented Kalman filter (UKF) was adopted to solve the nonlinear state transfer function in order to evolve the state of the target tissue, which involves estimation of the motion trajectory of the CCA wall from noisy ultrasound images. The performance of this approach has been validated on 30 simulated ultrasound sequences and a real ultrasound dataset of 103 subjects by comparing the motion tracking results obtained in this study to those of three state-of-the-art methods and of the manual tracing method performed by two experienced ultrasound physicians. The experimental results demonstrated that the proposed approach is highly correlated with (intra-class correlation coefficient ≥ 0.9948 for the longitudinal motion and ≥ 0.9966 for the radial motion) and well agrees (the 95% confidence interval width is 0.8871 mm for the longitudinal motion and 0.4159 mm for the radial motion) with the manual tracing method on real data and also exhibits high accuracy on simulated data (0.1161 ~ 0.1260 mm). These results appear to demonstrate the effectiveness of the proposed approach for motion tracking of the CCA wall.

A study of quantification of aortic compliance in mice using radial acquisition phase contrast MRI

NASA Astrophysics Data System (ADS)

Zhao, Xuandong

Spatiotemporal changes in blood flow velocity measured using Phase contrast Magnetic Resonance Imaging (MRI) can be used to quantify Pulse Wave Velocity (PWV) and Wall Shear Stress (WSS), well known indices of vessel compliance. A study was conducted to measure the PWV in the aortic arch in young healthy children using conventional phase contrast MRI and a post processing algorithm that automatically track the peak velocity in phase contrast images. It is shown that the PWV calculated using peak velocity-time data has less variability compared to that using mean velocity and flow. Conventional MR data acquisition techniques lack both the spatial and temporal resolution needed to accurately calculate PWV and WSS in in vivo studies using transgenic animal models of arterial diseases. Radial k-space acquisition can improve both spatial and temporal resolution. A major part of this thesis was devoted to developing technology for Radial Phase Contrast Magnetic Resonance (RPCMR) cine imaging on a 7 Tesla Animal scanner. A pulse sequence with asymmetric radial k-space acquisition was designed and implemented. Software developed to reconstruct the RPCMR images include gridding, density compensation and centering of k-Space that corrects the image ghosting introduced by hardware response time. Image processing software was developed to automatically segment the vessel lumen and correct for phase offset due to eddy currents. Finally, in vivo and ex vivo aortic compliance measurements were conducted in a well-established mouse model for atherosclerosis: Apolipoprotein E-knockout (ApoE-KO). Using RPCMR technique, a significantly higher PWV value as well as a higher average WSS was detected among 9 months old ApoE-KO mice compare to in wild type mice. A follow up ex-vivo test of tissue elasticity confirmed the impaired distensibility of aortic arteries among ApoE-KO mice.

2-D Versus 3-D Cross-Correlation-Based Radial and Circumferential Strain Estimation Using Multiplane 2-D Ultrafast Ultrasound in a 3-D Atherosclerotic Carotid Artery Model.

PubMed

Fekkes, Stein; Swillens, Abigail E S; Hansen, Hendrik H G; Saris, Anne E C M; Nillesen, Maartje M; Iannaccone, Francesco; Segers, Patrick; de Korte, Chris L

2016-10-01

Three-dimensional (3-D) strain estimation might improve the detection and localization of high strain regions in the carotid artery (CA) for identification of vulnerable plaques. This paper compares 2-D versus 3-D displacement estimation in terms of radial and circumferential strain using simulated ultrasound (US) images of a patient-specific 3-D atherosclerotic CA model at the bifurcation embedded in surrounding tissue generated with ABAQUS software. Global longitudinal motion was superimposed to the model based on the literature data. A Philips L11-3 linear array transducer was simulated, which transmitted plane waves at three alternating angles at a pulse repetition rate of 10 kHz. Interframe (IF) radio-frequency US data were simulated in Field II for 191 equally spaced longitudinal positions of the internal CA. Accumulated radial and circumferential displacements were estimated using tracking of the IF displacements estimated by a two-step normalized cross-correlation method and displacement compounding. Least-squares strain estimation was performed to determine accumulated radial and circumferential strain. The performance of the 2-D and 3-D methods was compared by calculating the root-mean-squared error of the estimated strains with respect to the reference strains obtained from the model. More accurate strain images were obtained using the 3-D displacement estimation for the entire cardiac cycle. The 3-D technique clearly outperformed the 2-D technique in phases with high IF longitudinal motion. In fact, the large IF longitudinal motion rendered it impossible to accurately track the tissue and cumulate strains over the entire cardiac cycle with the 2-D technique.

Vascular patterns of upper limb: an anatomical study with accent on superficial brachial artery

PubMed Central

Kachlik, David; Konarik, Marek; Baca, Vaclav

2011-01-01

The aim of the study was to evaluate the terminal segmentation of the axillary artery and to present four cases of anomalous branching of the axillary artery, the superficial brachial artery (arteria brachialis superficialis), which is defined as the brachial artery that runs superficially to the median nerve. Totally, 130 cadaveric upper arms embalmed by classical formaldehyde technique from collections of the Department of Anatomy, Third Faculty of Medicine, Charles University in Prague, were macroscopically dissected with special focus on the branching arrangement of the axillary artery. The most distal part of the axillary artery (infrapectoral part) terminated in four cases as a bifurcation into two terminal branches: the superficial brachial artery and profunda brachii artery, denominated according to their relation to the median nerve. The profunda brachii artery primarily gave rise to the main branches of the infrapectoral part of the axillary artery. The superficial brachial artery descended to the cubital fossa where it assumed the usual course of the brachial artery in two cases and in the other two cases its branches (the radial and ulnar arteries) passed superficially to the flexors. The incidence of the superficial brachial artery in our study was 5% of cases. The reported incidence is a bit contradictory, from 0.12% to 25% of cases. The anatomical knowledge of the axillary region is of crucial importance for neurosurgeons and specialists using the radiodiagnostic techniques, particularly in cases involving traumatic injuries. The improved knowledge would allow more accurate diagnostic interpretations and surgical treatment. PMID:21342134

Calf Perforator Flaps: A Freestyle Solution for Oral Cavity Reconstruction.

PubMed

Molina, Alexandra R; Citron, Isabelle; Chinaka, Fungayi; Cascarini, Luke; Townley, William A

2017-02-01

Reconstruction of oral cavity defects requires a thin, pliable flap for optimal functional results. Traditional flap choices are imperfect: the anterolateral thigh flap is excessively thick, whereas the radial forearm flap has a poor donor site. The authors therefore favor calf perforator flaps such as the medial sural artery perforator flap to provide thin tissue with an acceptable donor site. This two-part study aims to demonstrate their suitability for intraoral reconstruction. In the radiologic part of the study, the authors compared thigh and calf tissue thickness by examining lower limb computed tomographic scans of 100 legs. For their clinical study, they collected data prospectively on 20 cases of oral cavity reconstruction using calf perforator flaps. The mean thickness of the calf tissue envelope was significantly less than that of the thigh (8.4 mm compared with 17 mm) based on computed tomographic analysis. In the clinical study, a medial sural artery perforator was used in the majority of cases (17 of 20). The mean pedicle length was 10.2 cm and the mean time to raise a flap was 85 minutes. There were no flap losses. One patient was returned to the operating room for management of late hematoma and wound dehiscence. Calf perforator flaps provide ideal tissue for intraoral reconstruction and are significantly thinner than anterolateral thigh flaps. In addition to medial sural artery perforator flaps, the authors raised both sural and soleal artery perforator flaps in this series. Opportunistic use of the calf donor site allows the harvest of thin tissue with minimal donor-site morbidity. Therapeutic, IV.

Design and application of pulse information acquisition and analysis system with dynamic recognition in traditional Chinese medicine.

PubMed

Zhang, Jian; Niu, Xin; Yang, Xue-zhi; Zhu, Qing-wen; Li, Hai-yan; Wang, Xuan; Zhang, Zhi-guo; Sha, Hong

2014-09-01

To design the pulse information which includes the parameter of pulse-position, pulse-number, pulse-shape and pulse-force acquisition and analysis system with function of dynamic recognition, and research the digitalization and visualization of some common cardiovascular mechanism of single pulse. To use some flexible sensors to catch the radial artery pressure pulse wave and utilize the high frequency B mode ultrasound scanning technology to synchronously obtain the information of radial extension and axial movement, by the way of dynamic images, then the gathered information was analyzed and processed together with ECG. Finally, the pulse information acquisition and analysis system was established which has the features of visualization and dynamic recognition, and it was applied to serve for ten healthy adults. The new system overcome the disadvantage of one-dimensional pulse information acquisition and process method which was common used in current research area of pulse diagnosis in traditional Chinese Medicine, initiated a new way of pulse diagnosis which has the new features of dynamic recognition, two-dimensional information acquisition, multiplex signals combination and deep data mining. The newly developed system could translate the pulse signals into digital, visual and measurable motion information of vessel.

Evaluation of the Effects of Acupuncture on Blood Flow in Humans with Ultrasound Color Doppler Imaging

PubMed Central

Takayama, Shin; Watanabe, Masashi; Kusuyama, Hiroko; Nagase, Satoru; Seki, Takashi; Nakazawa, Toru; Yaegashi, Nobuo

2012-01-01

Color Doppler imaging (CDI) can be used to noninvasively create images of human blood vessels and quantitatively evaluate blood flow in real-time. The purpose of this study was to assess the effects of acupuncture on the blood flow of the peripheral, mesenteric, and retrobulbar arteries by CDI. Statistical significance was defined as P values less than 0.05. Blood flow in the radial and brachial arteries was significantly lower during needle stimulation on LR3 than before in healthy volunteers, but was significantly higher after needle stimulation than before. LR3 stimulation also resulted in a significant decrease in the vascular resistance of the short posterior ciliary artery and no significant change of blood flow through the superior mesenteric artery (SMA) during acupuncture. In contrast, ST36 stimulation resulted in a significant increase in blood flow through the SMA and no significant change in the vascular resistance of the retrobulbar arteries. Additionally, acupuncture at previously determined acupoints in patients with open-angle glaucoma led to a significant reduction in the vascular resistance of the central retinal artery and short posterior ciliary artery. Our results suggest that acupuncture can affect blood flow of the peripheral, mesenteric, and retrobulbar arteries, and CDI can be useful to evaluate hemodynamic changes by acupuncture. PMID:22778772

Penile fracture and penile reconstruction.

PubMed

Garaffa, Giulio; Raheem, Amr Abdel; Ralph, David John

2011-12-01

The past decade has seen a significant development in penile reconstruction techniques, and the management of penile fracture has progressively shifted from a conservative approach to early surgical repair. The radial artery-based free flap phalloplasty now represents the gold-standard procedure for total phallic reconstruction both in men and in female-to-male transsexuals.

Early first trimester uteroplacental flow and the progressive disintegration of spiral artery plugs: new insights from contrast-enhanced ultrasound and tissue histopathology.

PubMed

Roberts, V H J; Morgan, T K; Bednarek, P; Morita, M; Burton, G J; Lo, J O; Frias, A E

2017-12-01

Does the use of a vascular contrast agent facilitate earlier detection of maternal flow to the placental intervillous space (IVS) in the first trimester of pregnancy? Microvascular filling of the IVS was demonstrated by contrast-enhanced ultrasound from 6 weeks of gestation onwards, earlier than previously believed. During placental establishment and remodeling of maternal spiral arteries, endovascular trophoblast cells invade and accumulate in the lumen of these vessels to form 'trophoblast plugs'. Prior evidence from morphological and Doppler ultrasound studies has been conflicting as to whether the spiral arteries are completely plugged, preventing maternal blood flow to the IVS until late in the first trimester. Uteroplacental flow was examined across the first trimester in human subjects given an intravenous infusion of lipid-shelled octofluoropropane microbubbles with ultrasound measurement of destruction and replenishment kinetics. We also performed a comprehensive histopathological correlation using two separately archived uteroplacental tissue collections to evaluate the degree of spiral artery plugging and evaluate remodeling of the upstream myometrial radial and arcurate arteries. Pregnant women (n = 34) were recruited in the first trimester (range: 6+3 to 13+6 weeks gestation) for contrast-enhanced ultrasound studies with destruction-replenishment analysis of signal intensity for assessment of microvascular flux rate. Histological samples from archived in situ (Boyd Collection, n = 11) and fresh first, second, and third trimester decidual and post-hysterectomy uterine specimens (n = 16) were evaluated by immunohistochemistry (using markers of epithelial, endothelial and T-cells, as well as cell adhesion and proliferation) and ultrastructural analysis. Contrast agent entry into the IVS was visualized as early as 6+3 weeks of gestation with some variability in microvascular flux rate noted in the 6-7+6 week samples. Spiral artery plug canalization was observed from 7 weeks with progressive disintegration thereafter. Of note, microvascular flux rate did not progressively increase until 13 weeks, which suggests that resistance to maternal flow in the early placenta may be mediated more proximally by myometrial radial arteries that begin remodeling at the end of the first trimester. Gestational age was determined by crown-rump length measurements obtained by transvaginal ultrasound on the day of contrast-enhanced imaging studies, which may explain the variability in the earliest gestational age samples due to the margin of error in this type of measurement. Our comprehensive in situ histological analysis, in combination with the use of an in vivo imaging modality that has the sensitivity to permit visualization of microvascular filling, has allowed us to reveal new evidence in support of increasing blood flow to the IVS from 6 weeks of gestation. Histologic review suggested the mechanism may be blood flow through capillary-sized channels that form through the loosely cohesive 'plugs' by 7 weeks gestation. However, spiral artery remodeling on its own did not appear to explain why there is significantly more blood flow at 13 weeks gestation. Histologic studies suggest it may be related to radial artery remodeling, which begins at the end of the first trimester. This project was supported by the Oregon Health and Science University Knight Cardiovascular Institute, Center for Developmental Health and the Struble Foundation. There are no competing interests. © The Author 2017. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com

"One-Stop Shop": Free-Breathing Dynamic Contrast-Enhanced Magnetic Resonance Imaging of the Kidney Using Iterative Reconstruction and Continuous Golden-Angle Radial Sampling.

PubMed

Riffel, Philipp; Zoellner, Frank G; Budjan, Johannes; Grimm, Robert; Block, Tobias K; Schoenberg, Stefan O; Hausmann, Daniel

2016-11-01

The purpose of the present study was to evaluate a recently introduced technique for free-breathing dynamic contrast-enhanced renal magnetic resonance imaging (MRI) applying a combination of radial k-space sampling, parallel imaging, and compressed sensing. The technique allows retrospective reconstruction of 2 motion-suppressed sets of images from the same acquisition: one with lower temporal resolution but improved image quality for subjective image analysis, and one with high temporal resolution for quantitative perfusion analysis. In this study, 25 patients underwent a kidney examination, including a prototypical fat-suppressed, golden-angle radial stack-of-stars T1-weighted 3-dimensional spoiled gradient-echo examination (GRASP) performed after contrast agent administration during free breathing. Images were reconstructed at temporal resolutions of 55 spokes per frame (6.2 seconds) and 13 spokes per frame (1.5 seconds). The GRASP images were evaluated by 2 blinded radiologists. First, the reconstructions with low temporal resolution underwent subjective image analysis: the radiologists assessed the best arterial phase and the best renal phase and rated image quality score for each patient on a 5-point Likert-type scale.In addition, the diagnostic confidence was rated according to a 3-point Likert-type scale. Similarly, respiratory motion artifacts and streak artifacts were rated according to a 3-point Likert-type scale.Then, the reconstructions with high temporal resolution were analyzed with a voxel-by-voxel deconvolution approach to determine the renal plasma flow, and the results were compared with values reported in previous literature. Reader 1 and reader 2 rated the overall image quality score for the best arterial phase and the best renal phase with a median image quality score of 4 (good image quality) for both phases, respectively. A high diagnostic confidence (median score of 3) was observed. There were no respiratory motion artifacts in any of the patients. Streak artifacts were present in all of the patients, but did not compromise diagnostic image quality.The estimated renal plasma flow was slightly higher (295 ± 78 mL/100 mL per minute) than reported in previous MRI-based studies, but also closer to the physiologically expected value. Dynamic, motion-suppressed contrast-enhanced renal MRI can be performed in high diagnostic quality during free breathing using a combination of golden-angle radial sampling, parallel imaging, and compressed sensing. Both morphologic and quantitative functional information can be acquired within a single acquisition.

Coronary Revascularization in Children at a Mexican Cardiac Center: Thirteen-Year Outcomes.

PubMed

Ramírez-Marroquín, Samuel E; Iturriaga-Hernández, Alejandra; Calderón-Colmenero, Juan; Benita-Bordes, Antonio; Cervantes-Salazar, Jorge L

2017-09-01

The indications for pediatric coronary revascularization are diverse. There are a large proportion of patients with sequelae of severe inflammatory diseases such as Kawasaki disease, and other less common causes. Retrospective review of ten pediatric patients undergoing coronary artery bypass surgery from January 2004 to December 2016. Ten children and adolescents ranging in age from 2 to 17 (median, 6) years at operation were followed up for as long as 13 years with a median follow-up of 2 years. The surgical indications include ischemia symptoms and/or coronary stenosis angiographically documented. Diagnoses include Kawasaki disease, anomalous origin of the left coronary artery from the pulmonary artery, and iatrogenic lesion of the right coronary artery. All the surgical procedures were performed with cardiopulmonary bypass with crystalloid cardioplegic arrest. The number of distal anastomoses was 1.6 per patient, and the left internal thoracic artery was used in one patient, the right internal thoracic artery in four patients, bilateral internal thoracic artery in four patients, and bilateral internal thoracic artery plus left radial artery in one patient, most frequently for right coronary artery revascularization. The patients underwent noninvasive diagnostic study during follow-up to evaluate their coronary status. The ten patients had no symptoms, and there was no mortality. Although survival was excellent after pediatric coronary bypass in our center, we need to continue the follow-up. Coronary revascularization by means of arterial grafting is a safe and reliable surgical modality for coronary disease in children.

Reconstruction of totally degloved fingers: a novel application of the bilobed spiraled innervated radial artery superficial palmar branch perforator flap design provides for primary donor-site closure.

PubMed

Chi, Zhenglin; Yang, Peng; Song, Dajiang; Li, Zan; Tang, Liang; Gao, Weiyang; Song, Yonghuan; Chu, Tingang

2017-05-01

To investigate the results of resurfacing completely degloved digits using bilobed innervated radial artery superficial palmar branch (RASPB) perforator flap in a spiral fashion. A detailed anatomic study on 30 adult fresh frozen cadavers preinjected with silicone rubber compound to demarcate arterial anatomy documented locations, numbers, and diameters of arteries and skin perforators with surrounding nerves. The flap-raising procedure was performed using four fresh cadaver specimen. We reviewed the reconstruction of 12 digits by using a bilobed spiraled innervated RASPB free perforator flap after non-replantable degloving injury. Two skin paddles were marked out using standard points of reference. At least two separate cutaneous perforator vessels were identified using a hand-held Doppler and were dissected back to the RASPB in retrograde fashion. The skin paddles were then divided between the two cutaneous perforators to provide two separate paddles with a common vascular supply. The skin paddles were stacked in a spiral fashion on the flap inset, effectively increasing the width of the flap to cover the totally degloved finger while still allowing closure of the primary donor-site. The RASPB was present within the flap in all cadavers. The direct perforator and the musculocutaneous perforator were available in 93.33 and 76.67 %, respectively, with neither of them in 6.67 % of the cases. The constantly present two perforators allowed the design of a new bilobed spiraled innervated radial artery superficial palmar branch perforator flap. We used the proposed flap to reconstruct completely degloved digits in 12 patients (mean age 28.6 years; range 17-35 years). With our proposed flap, no flap failure or re-exploration occurred and the donor site was closed primarily in all cases. All the flaps survived uneventfully. Total active motion ranged from 92° to 140° and 111° to 155° in the cases with and without metacarpophalangeal joint involvement, respectively. The static 2 point discrimination test varied from 6 to 11 mm. All the patients were satisfied with the overall results. The bilobed flap is large enough to cover totally degloved finger defects and contain direct skin perforators, provides a bespoke cover for complex soft tissue defects of completely degloved digits while also improving morbidity and cosmesis of the donor site. Level IV, retrospective series.

Effectiveness of a smartphone application for improving healthy lifestyles, a randomized clinical trial (EVIDENT II): study protocol.

PubMed

Recio-Rodríguez, José I; Martín-Cantera, Carlos; González-Viejo, Natividad; Gómez-Arranz, Amparo; Arietaleanizbeascoa, Maria S; Schmolling-Guinovart, Yolanda; Maderuelo-Fernandez, Jose A; Pérez-Arechaederra, Diana; Rodriguez-Sanchez, Emiliano; Gómez-Marcos, Manuel A; García-Ortiz, Luis

2014-03-15

New technologies could facilitate changes in lifestyle and improve public health. However, no large randomized, controlled studies providing scientific evidence of the benefits of their use have been made. The aims of this study are to develop and validate a smartphone application, and to evaluate the effect of adding this tool to a standardized intervention designed to improve adherence to the Mediterranean diet and to physical activity. An evaluation is also made of the effect of modifying habits upon vascular structure and function, and therefore on arterial aging. A randomized, double-blind, multicenter, parallel group clinical trial will be carried out. A total of 1215 subjects under 70 years of age from the EVIDENT trial will be included. Counseling common to both groups (control and intervention) will be provided on adaptation to the Mediterranean diet and on physical activity. The intervention group moreover will receive training on the use of a smartphone application designed to promote a healthy diet and increased physical activity, and will use the application for three months. The main study endpoints will be the changes in physical activity, assessed by accelerometer and the 7-day Physical Activity Recall (PAR) interview, and adaptation to the Mediterranean diet, as evaluated by an adherence questionnaire and a food frequency questionnaire (FFQ). Evaluation also will be made of vascular structure and function based on central arterial pressure, the radial augmentation index, pulse velocity, the cardio-ankle vascular index, and carotid intima-media thickness. Confirmation that the new technologies are useful for promoting healthier lifestyles and that their effects are beneficial in terms of arterial aging will have important clinical implications, and may contribute to generalize their application in favor of improved population health. Clinical Trials.gov Identifier: NCT02016014.

Noninvasive detection of coronary artery bypass graft patency by intravenous electron beam computed tomographic angiography.

PubMed

Yamakami, Shoji; Toyama, Junji; Okamoto, Mitsuhiro; Matsushita, Toyoaki; Murakami, Yoshimasa; Ogata, Masaki; Ito, Shigenori; Fukutomi, Tatsuya; Okayama, Naotsuka; Itoh, Makoto

2003-11-01

This study evaluates the usefullness of intravenous electron beam computed tomographic angiography (EBA) for the detection of coronary artery bypass graft patency in 43 patients (33 men and 10 women, mean age, 65 years) who had coronary artery bypass graft surgery. EBA was performed a few days before selective bypass graft angiography (SGA). Forty axial cross-sections of angiographic images of the heart were acquired consecutively by an electrocardiographic trigger signal at 40% of the RR interval, which corresponds to the end-systolic phase. EBA data were reconstructed as a three-dimensional shaded surface display of the heart and bypass grafts. Detectability of the patency of bypass gratis was evaluated, taking selective angiographic images of the bypass grafts as a gold standard. One hundred and nine grafts (96%) out of 114 grafts were subjected to evaluation: 37 grafts were left internal mammary artery grafts (LIMA), 7 were right internal mammary artery grafts (RIMA), 6 were gastroepiploic artery grafts (GEA), 7 were free gastroepiploic artery grafts with venous drainage (free-GEA), 7 were radial artery grafts (RAG), and 45 were saphenous vein gratis (SVG). The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of EBA were 98%, 100%, 100%, 91%, and 98%, respectively. EBA sampled at the end-systolic period was determined to be useful for the detection of coronary artery bypass graft patency and occlusion.

Stent design favorably influences the vascular response in normal porcine coronary arteries.

PubMed

Carter, A J; Scott, D; Rahdert, D; Bailey, L; De Vries J; Ayerdi, K; Turnlund, T; Jones, R; Virmani, R; Fischell, T A

1999-03-01

The purpose of this study was to compare the arterial response following implantation of a stainless-steel, balloon-expandable, tubular slotted stent with that of a novel computer-designed, multi-cellular stent in normal porcine coronary arteries. Intracoronary stent placement has evolved into the primary strategy for percutaneous revascularization of symptomatic coronary arterial lesions. Presently there is intense interest in developing new stent designs to improve stent delivery and biocompatability. Computer-assisted design was utilized to develop a balloon-expandable stent with symmetric expansion properties, uniform arterial wall coverage, longitudinal flexibility and radial strength. Quantitative coronary angiography and histological assessment of the stented arteries was used to evaluate the acute and chronic vascular responses to a stainless-steel, balloon-expandable, tubular slotted stent as compared to the computer-designed BX stent in the normolipemic swine. Forty stents (24 BX, 16 tubular slotted) were implanted in 19 miniature swine at a mean inflation pressure of 9 atm using identical delivery systems. Eight of the BX and none of the tubular slotted stents were post-dilated with a non-compliant balloon at 12-14 atm. The mean stent-to-artery ratio was similar for the BX (1.03 +/- 0.06) and tubular slotted (1.04 +/- 0.11; p = 0.59) designs. Protrusion or asymmetric radial flaring of a strut at the stent margin was present in 1 of 23 BX stents (4.3%) and 10 of 15 tubular slotted stents (66.7%; p < 0.0001). The mean arterial injury score was significantly less for the BX stent (0.2 +/- 0.2) as compared with the tubular slotted stents (0.4 +/- 0.4; p = 0.025). At 3 days, thrombus area was similar for the BX and tubular slotted designs (0.42 +/- 0.16 mm2 versus 0.44 +/- 0.18 mm2, respectively; p = 0.88). The mean neointimal area was significantly less for the BX at 2 months (1.09 +/- 0.25 mm2 versus 2.93 +/- 2.26 mm2 in the tubular slotted stent) and at 6 months (1.10 +/- 0.26 mm2 versus 2.07 +/- 0.65 mm2 in the tubular slotted stent; p = 0.01), resulting in approximately 50% less in-stent stenosis. The arterial response to a balloon-expandable stent can be favorably influenced by computer-assisted modification of design in an experimental model. Further study is warranted to determine the impact of stent design upon clinical in-stent restenosis.

Resistance of uterine radial artery blood flow was correlated with peripheral blood NK cell fraction and improved with low molecular weight heparin therapy in women with unexplained recurrent pregnancy loss.

PubMed

Koo, Hwa Seon; Kwak-Kim, Joanne; Yi, Hyun Jeong; Ahn, Hyun Kyong; Park, Chan Woo; Cha, Sun Hwa; Kang, Inn Soo; Yang, Kwang Moon

2015-02-01

To investigate whether peripheral blood natural killer (pbNK) cell levels are associated with uterine blood flow, and low molecular weight heparin (LMWH) treatment is effective to improve uterine blood flow in women with decreased uterine blood flow and unexplained recurrent pregnancy loss (RPL). This was a prospective controlled study. Study population included 33 pregnant women (between 5 and 7 weeks gestation) with ≥ 2 RPL and controls were 47 healthy pregnant women. pbNK cell fractions (CD3(-)/56(+)/16(+)) of peripheral blood mononuclear cells were measured by flow cytometry. Uterine color-pulsed Doppler ultrasound was performed to evaluate uterine radial artery resistance index (URa-RI). In RPL women with elevated URa-RI (≥ 0.5), LMWH (ranges 40-60 mg/day) was administered subcutaneously daily and URa-RI was reassessed 1 week later. Pregnancy outcome was analyzed at 12 weeks gestation. URa-RI was significantly higher in pregnant women with RPL than controls (0.60 ± 0.14 versus 0.54 ± 0.12, P = 0.039). In pregnant women with RPL, pbNK cell fractions displayed a positive correlation with URa-RI (Pearson's r = 0.429, P = 0.013). URa-RI was significantly decreased 1 week after LMWH treatment as compared to that of pretreatment (pretreatment RI: 0.65 ± 0.11 versus post-treatment RI: 0.56 ± 0.13, P = 0.011). Pregnancy outcome of RPL women with LMWH treatment was not different from that of pregnant controls (73.3% versus 85.0%, P = NS). Increased pbNK cells are associated with decreased uterine radial artery blood flow. LMWH treatment effectively decreases URa-RI with improved pregnancy outcome in women with RPLs and elevated URa-RI. A larger scale study is needed to verify these findings. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Inflammation disrupts the LDL receptor pathway and accelerates the progression of vascular calcification in ESRD patients.

PubMed

Liu, Jing; Ma, Kun Ling; Gao, Min; Wang, Chang Xian; Ni, Jie; Zhang, Yang; Zhang, Xiao Liang; Liu, Hong; Wang, Yan Li; Liu, Bi Cheng

2012-01-01

Chronic inflammation plays a crucial role in the progression of vascular calcification (VC). This study was designed to investigate whether the low-density lipoprotein receptor (LDLr) pathway is involved in the progression of VC in patients with end-stage renal disease (ESRD) during inflammation. Twenty-eight ESRD patients were divided into control and inflamed groups according to plasma C-reactive protein (CRP) level. Surgically removed tissues from the radial arteries of patients receiving arteriovenostomy were used in the experiments. The expression of tumour necrosis factor-α (TNF-α) and monocyte chemotactic protein-1 (MCP-1) of the radial artery were increased in the inflamed group. Hematoxylin-eosin and alizarin red S staining revealed parallel increases in foam cell formation and calcium deposit formation in continuous cross-sections of radial arteries in the inflamed group compared to the control, which were closely correlated with increased LDLr, sterol regulatory element binding protein-2 (SREBP-2), bone morphogenetic proteins-2 (BMP-2), and collagen I protein expression, as shown by immunohistochemical and immunofluorescent staining. Confocal microscopy confirmed that inflammation enhanced the translocation of the SREBP cleavage-activating protein (SCAP)/SREBP-2 complex from the endoplasmic reticulum to the Golgi, thereby activating LDLr gene transcription. Inflammation increased alkaline phosphatase protein expression and reduced α-smooth muscle actin protein expression, contributing to the conversion of the vascular smooth muscle cells in calcified vessels from the fibroblastic to the osteogenic phenotype; osteogenic cells are the main cellular components involved in VC. Further analysis showed that the inflammation-induced disruption of the LDLr pathway was significantly associated with enhanced BMP-2 and collagen I expression. Inflammation accelerated the progression of VC in ESRD patients by disrupting the LDLr pathway, which may represent a novel mechanism involved in the progression of both VC and atherosclerosis.

Outcomes of Interventions Via a Transradial Approach for Dysfunctional Brescia-Cimino Fistulas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen Shyhming; Hang Chiling; Yip Honkan

2009-09-15

The transradial artery approach to angioplasty has rarely been reported as a method for treating dysfunctional Brescia-Cimino fistulas. This study evaluated the feasibility, safety, and 1-year efficacy of this method for treating dysfunctional Brescia-Cimino fistulas. We retrospectively evaluated 154 consecutive procedures in 131 patients (age, 58.3 {+-} 11.6 years; male, 48.1%) who underwent the transradial approach in dysfunctional Brescia-Cimino fistulas in the 1-year period after the procedure. The operator determined the use of a regular or a cutting balloon (two cases) in combination with urokinase injection (one case) or catheter thromboaspiration. Radial artery puncture was successful in all cases. Fifty-twomore » cases (33.8%) had totally occluded fibrotic lesions. The overall anatomic success rate and clinical success rate were 61% (94/154) and 81.1% (125/154), respectively. In cases with a totally occluded fibrotic lesion, the clinical success rate was 46%. Successful intervention was associated with a significant reduction in the radial arterial systolic and diastolic pressures. There were no complications of symptomatic arterial embolization or pulmonary embolism, and one complication of venous rupture was successfully treated by compression. The primary patency rates based on intention-to-treat were 75.3% at 30 days and 39.0% at 1 year after the procedure. Excluding the cases with a totally occluded lesion, the clinical success rate was 99% (101/102) and the primary patency rates were 84.3% (86/102) and 52.0% (53/102) at 3 months and 1 year after the procedure, respectively. In conclusion, the transradial approach is a feasible, safe, and effective alternative for catheter intervention for dysfunctional Brescia-Cimino fistulas. Its success rate in cases with a totally occluded fibrotic lesion is unsatisfactory.« less

[Radial Approach for Percutaneous Coronary Interventions in Patients With Ischemic Heart Disease: Advantages and Disadvantages, Complications Rate in Comparison With Femoral Approach].

PubMed

Fettser, D V; Batyraliev, T A; Pershukov, I V; Vanyukov, A E; Sidorenko, B A

2017-05-01

During recent 10-15 years, percutaneous coronary interventions (PCI) have reached a new level of efficacy and safety. Rate of serious coronary complications has decreased. That to a greater degree exposes the problem of peripheral complications at the site of arterial approach. At the same time portion of patients older than 75 years in the total pool of PCI constantly increases. Number of patients with pronounced obesity also grows each year. Radial approach for PCI allows to substantially decrease rate of peripheral complications at the account of lowered rate of bleedings, and to shorten duration of hospitalization. In this literature review we present results of a number of relevant clinical studies including those which contained groups of elderly patients and of patients with obesity. We also have summarized main advantages and disadvantages of radial approach as compared with femoral approach for coronary angiography and PCI.

Insulin resistance in hyperthyroidism: the role of IL6 and TNF alpha.

PubMed

Mitrou, Panayota; Boutati, Eleni; Lambadiari, Vaia; Tsegka, Aikaterini; Raptis, Athanasios E; Tountas, Nikolaos; Economopoulos, Theofanis; Raptis, Sotirios A; Dimitriadis, George

2010-01-01

Although insulin resistance is a common finding in hyperthyroidism, the implicated mechanisms are obscure. The aim of this study was to investigate whether interleukin 6 (IL6) and tumour necrosis factor alpha (TNFalpha) are related to the development of insulin resistance in hyperthyroidism of nonautoimmune origin. A meal was given to ten hyperthyroid (HR) and ten euthyroid (EU) women. Plasma samples were taken for 360 min from the radial artery for measurements of glucose, insulin, and nonesterified fatty acids (NEFA). IL6 and TNFalpha were measured preprandially from the superficial epigastric vein and from the radial artery. i) In HR versus EU: (a) arterial glucose was similar (AUC(0-360) 2087+/-57 vs 2010+/-43 mM x min), but insulin was increased (AUC(0-360) 17 267+/-2447 vs 10 331+/-666 microU/ml x min, P=0.01), (b) homeostasis model assessment (HOMA) was increased (2.3+/-0.4 vs 1+/-0.1 kg/m(2), P=0.007), (c) arterial NEFA were increased (AUC(0-360) 136+/-18 vs 89+/-7 mmol/lxmin, P=0.03), (d) arterial IL6 (2+/-0.3 vs 0.9+/-0.1 pg/ml, P=0.0009) and TNFalpha (4.2+/-0.8 vs 1.5+/-0.2 pg/ml, P=0.003) were increased, and (e) IL6 production from the subcutaneous adipose tissue (AT) was increased (18+/-6 vs 5+/-1 pg/min per 100 ml tissue, P=0.04). ii) (a) Subcutaneous venous IL6 was positively associated with HOMA (beta-coefficient=1.7+/-0.7, P=0.049) and (b) although TNFalpha was not produced by the subcutaneous AT, arterial TNFalpha was positively associated with NEFA (AUC(0-360); beta-coefficient=0.045+/-0.01, P=0.005). In hyperthyroidism: i) glucose and lipid metabolism are resistant to insulin, ii) subcutaneous AT releases IL6, which could then act as an endocrine mediator of insulin resistance, iii) although there is no net secretion of TNFalpha by the subcutaneous AT, increased systemic TNFalpha levels may be related to the development of insulin resistance in lipolysis.

Double-arterial cannulation for aortic valve replacement with porcelain aorta.

PubMed

De Paulis, Ruggero; Maselli, Daniele; Scaffa, Raffaele; Nardella, Saverio

2009-10-01

We describe a new technique of aortic valve replacement (AVR) in patients with porcelain aorta. Three patients (mean age 75 years) were treated. The cardiopulmonary bypass (CPB) was established after side-graft right axillary artery and direct femoral artery cannulation. Venous drainage was obtained by atrio-caval cannulation. The procedures were performed in mild hypothermia (30 degrees C). Cerebral perfusion was carried out by clamping the innominate artery and all epiaortic vessels. The aorta was endoclamped by a Foley balloon inserted into the isthmus. The aorta was then opened longitudinally for 10 cm to expose and replace the aortic valve. Near-infra-red spectroscopy (NIRS) and bilateral radial artery pressure were used to monitor effective cerebral perfusion. Operative mortality was absent. The mean time of CPB was 73 min. NIRS-derived tissue oxygenation was maintained above 55%. Postoperative course was uneventful. This technique has several advantages: first, the cannulation of right axillary and the common femoral artery allows simultaneous cerebral and systemic perfusion. Second, any form of cross-clamp is avoided and the aorta is occluded away from the epiaortic vessels. Third, there is an increased freedom to choose the best place for aortotomy.

Intraluminal laser atherectomy with ultrasound and electromagnetic guidance

NASA Astrophysics Data System (ADS)

Gregory, Kenton W.; Aretz, H. Thomas; Martinelli, Michael A.; LeDet, Earl G.; Hatch, G. F.; Gregg, Richard E.; Sedlacek, Tomas; Haase, Wayne C.

1991-05-01

The MagellanTM coronary laser atherectomy system is described. It uses high- resolution ultrasound imaging and electromagnetic sensing to provide real-time guidance and control of laser therapy in the coronary arteries. The system consists of a flexible catheter, an electromagnetic navigation antenna, a sensor signal processor and a computer for image processing and display. The small, flexible catheter combines an ultrasound transducer and laser delivery optics, aimed at the artery wall, and an electromagnetic receiving sensor. An extra-corporeal electromagnetic transmit antenna, in combination with catheter sensors, locates the position of the ultrasound and laser beams in the artery. Navigation and ultrasound data are processed electronically to produce real-time, transverse, and axial cross-section images of the artery wall at selected locations. By exploiting the ability of ultrasound to image beneath the surface of artery walls, it is possible to identify candidate treatment sites and perform safe radial laser debulking of atherosclerotic plaque with reduced danger of perforation. The utility of the system in plaque identification and ablation is demonstrated with imaging and experimental results.

Children and Adolescent Obesity Associates with Pressure-Dependent and Age-Related Increase in Carotid and Femoral Arteries' Stiffness and Not in Brachial Artery, Indicative of Nonintrinsic Arterial Wall Alteration

PubMed Central

García-Espinosa, Victoria; Curcio, Santiago; Castro, Juan Manuel; Arana, Maite; Giachetto, Gustavo; Chiesa, Pedro; Zócalo, Yanina

2016-01-01

Aim. To analyze if childhood obesity associates with changes in elastic, transitional, and/or muscular arteries' stiffness. Methods. 221 subjects (4–15 years, 92 females) were assigned to normal weight (NW, n = 137) or obesity (OB, n = 84) groups, considering their body mass index z-score. Age groups were defined: 4–8; 8–12; 12–15 years old. Carotid, femoral, and brachial artery local stiffness was determined through systodiastolic pressure-diameter and stress-strain relationships. To this end, arterial diameter and peripheral and aortic blood pressure (BP) levels and waveforms were recorded. Carotid-femoral, femoropedal, and carotid-radial pulse wave velocities were determined to evaluate aortic, lower-limb, and upper-limb regional arterial stiffness, respectively. Correlation analysis between stiffness parameters and BP was done. Results. Compared to NW, OB subjects showed higher peripheral and central BP and carotid and femoral stiffness, reaching statistical significance in subjects aged 12 and older. Arterial stiffness differences disappeared when levels were normalized for BP. There were no differences in intrinsic arterial wall stiffness (elastic modulus), BP stiffness relationships, and regional stiffness parameters. Conclusion. OB associates with BP-dependent and age-related increase in carotid and femoral (but not brachial) stiffness. Stiffness changes would not be explained by intrinsic arterial wall alterations but could be associated with the higher BP levels observed in obese children. PMID:27066273

Effect of coronary artery reperfusion on transmural myocardial remodeling in dogs.

PubMed

Ono, S; Waldman, L K; Yamashita, H; Covell, J W; Ross, J

1995-02-15

The effects of reperfusion after coronary occlusion on transmural remodeling of the ischemic region early and late after nontransmural infarction must importantly affect the recovery of regional function. Accordingly, analysis of local volume and three-dimensional strain was performed using a finite element method to determine regional remodeling. Systolic and remodeling strains were measured using radiographic imaging of three columns (approximately 1 cm apart) of four to six gold beads implanted across the left ventricular posterior wall in 6 dogs. After a control study, infarction was produced by 2 to 4 hours of proximal left circumflex coronary artery occlusion followed by reperfusion. Follow-up studies were performed at 2 days, 3 weeks, and 12 weeks with the dogs under anesthesia and in closed-chest conditions. Biplane cineradiography was performed to obtain the three-dimensional coordinates of the beads. At 2 days, end-systolic strains were akinetic with loss of normal transmural gradients of shortening and thickening. Remodeling strains (RS) were determined by use of a nonhomogeneous finite element method by referring the end-diastolic configuration during follow-up studies to its control state at matched end-diastolic pressures and heart rates. Tissue volume at 2 days increased substantially, more at the endocardium (30 +/- 7%) than at the epicardium (5 +/- 12%, P < .01); the increase was associated with an average RS in the wall-thickening direction of 0.18 +/- 0.15 (P < .01) with all other RS near zero. At 12 weeks systolic function partially recovered, with normal wall thickening in the epicardium (radial strain, 0.081 +/- 0.056 [control] versus 0.113 +/- 0.088 [12 weeks]) but with dysfunction in the endocardium (0.245 +/- 0.108 [control] versus 0.111 +/- 0.074 [P < .01] [12 weeks]). This inability of the inner wall to recover function may be related to increased transmural torsional shear and negative longitudinal-radial transverse shear in the inner wall. Volume loss occurred at 12 weeks in the endocardium (-36 +/- 16%) corresponding to transmural gradients in longitudinal RS and both transverse shear RS. Negative longitudinal RS was greater at the endocardium (-0.20 +/- 0.10) than at the epicardium (-0.06 +/- 0.05, P < .01). These results indicate the presence of marked subendocardial edema 2 days after reperfusion following 2 to 4 hours of coronary occlusion. At 3 months after reperfusion, however, there was volume loss in the inner wall due to shrinkage along the myofiber direction with reduced transmural function and loss of longitudinal shortening, while both tissue volume and function recovered completely in the outer wall.

4D flow MRI assessment of extracranial-intracranial bypass: qualitative and quantitative evaluation of the hemodynamics.

PubMed

Sekine, Tetsuro; Takagi, Ryo; Amano, Yasuo; Murai, Yasuo; Orita, Erika; Matsumura, Yoshio; Kumita, Shin-Ichiro

2016-03-01

Our aim was to assess the feasibility of using time-resolved 3D phase-contrast (4D flow) MRI to characterize extracranial-intracranial (EC-IC) bypass. We enrolled 32 patients who underwent EC-IC bypass (15 men, 17 women; mean age 66.4 years). In all, 16 underwent radial artery graft (RAG) bypass and 16 underwent superficial temporal artery (STA) bypass. 4D flow MRI, time-of-flight (TOF) magnetic resonance angiography (MRA), and computed tomography angiography (CTA) were performed. Bypass patency, flow direction, and blood flow volume (BFV) of each artery were determined by 4D flow MRI. Arterial diameters were measured by TOF-MRA and CTA. We compared RAG and STA bypasses by evaluating the flow direction and BFV of each artery. We evaluated the correlation between arterial diameters (measured by CTA or MRA) and the BFV and the detectability of flow direction (measured by 4D flow MRI) of each artery. 4D flow MRI confirmed the patency of each bypass artery. Flow direction of the M1 segment of the middle cerebral artery and BFV in the bypass artery differed between RAG and STA groups (p < 0.01). BFV in the bypass slightly correlated with the diameters on CTA (p < 0.05, R (2) = 0.287). Of the 29 arteries in the circle of Willis, nine were not depicted on 4D flow MRI. Cutoff values for arterial diameters on CTA and TOF-MRA for detecting the artery on 4D flow MRI were 2.4 and 1.8 mm, respectively. 4D flow MRI provided unique information for characterizing EC-IC bypasses, although this detectability is limited when addressing small arteries with slow flow.

In Silico Syndrome Prediction for Coronary Artery Disease in Traditional Chinese Medicine

PubMed Central

Lu, Peng; Chen, Jianxin; Zhao, Huihui; Gao, Yibo; Luo, Liangtao; Zuo, Xiaohan; Shi, Qi; Yang, Yiping; Yi, Jianqiang; Wang, Wei

2012-01-01

Coronary artery disease (CAD) is the leading causes of deaths in the world. The differentiation of syndrome (ZHENG) is the criterion of diagnosis and therapeutic in TCM. Therefore, syndrome prediction in silico can be improving the performance of treatment. In this paper, we present a Bayesian network framework to construct a high-confidence syndrome predictor based on the optimum subset, that is, collected by Support Vector Machine (SVM) feature selection. Syndrome of CAD can be divided into asthenia and sthenia syndromes. According to the hierarchical characteristics of syndrome, we firstly label every case three types of syndrome (asthenia, sthenia, or both) to solve several syndromes with some patients. On basis of the three syndromes' classes, we design SVM feature selection to achieve the optimum symptom subset and compare this subset with Markov blanket feature select using ROC. Using this subset, the six predictors of CAD's syndrome are constructed by the Bayesian network technique. We also design Naïve Bayes, C4.5 Logistic, Radial basis function (RBF) network compared with Bayesian network. In a conclusion, the Bayesian network method based on the optimum symptoms shows a practical method to predict six syndromes of CAD in TCM. PMID:22567030

AltitudeOmics: cerebral autoregulation during ascent, acclimatization, and re-exposure to high altitude and its relation with acute mountain sickness.

PubMed

Subudhi, Andrew W; Fan, Jui-Lin; Evero, Oghenero; Bourdillon, Nicolas; Kayser, Bengt; Julian, Colleen G; Lovering, Andrew T; Panerai, Ronney B; Roach, Robert C

2014-04-01

Cerebral autoregulation (CA) acts to maintain brain blood flow despite fluctuations in perfusion pressure. Acute hypoxia is thought to impair CA, but it is unclear if CA is affected by acclimatization or related to the development of acute mountain sickness (AMS). We assessed changes in CA using transfer function analysis of spontaneous fluctuations in radial artery blood pressure (indwelling catheter) and resulting changes in middle cerebral artery blood flow velocity (transcranial Doppler) in 21 active individuals at sea level upon arrival at 5,260 m (ALT1), after 16 days of acclimatization (ALT16), and upon re-exposure to 5,260 m after 7 days at 1,525 m (POST7). The Lake Louise Questionnaire was used to evaluate AMS symptom severity. CA was impaired upon arrival at ALT1 (P < 0.001) and did not change with acclimatization at ALT16 or upon re-exposure at POST7. CA was not associated with AMS symptoms (all R < 0.50, P > 0.05). These findings suggest that alterations in CA are an intrinsic consequence of hypoxia and are not directly related to the occurrence or severity of AMS.

Tailored flow sequestration treatment using high-flow and low-flow bypass for partially thrombosed giant internal carotid artery aneurysm-a technical case report.

PubMed

Hasegawa, Hirotaka; Inoue, Tomohiro; Tamura, Akira; Saito, Isamu

2016-10-01

Direct clipping of giant partially thrombosed intracranial internal carotid artery (ICA) aneurysms is challenging, especially when important perforating arteries are involved. Proximal occlusion with bypass represents a possible alternative approach. An 80-year-old female presented with worsening visual acuity and severe headache caused by partially thrombosed giant (38 mm in diameter) aneurysms of the right ICA, suggestive of impending rupture. Direct clipping in conjunction with temporary occlusion of the lesion involving the anterior choroidal artery (AChA) was considered too risky. Thus, we sequestrated the ipsilateral ICA flow into a low-flow and a high-flow system using two external carotid artery (ECA)-ICA bypasses and one in situ bypass with cervical ICA ligation. As a result, the low-flow system by the superficial temporal artery-middle cerebral artery (MCA) bypass perfused mainly the proximal MCA lesions and aneurysm, whereas the high-flow system by ECA-radial artery-M2 bypass exclusively supplied the residual distal MCA area. This tailored flow sequestration successfully interrupted intra-aneurysmal flow and accelerated near-complete thrombosis of the aneurysm while preserving the AChA and avoiding any significant neurological deterioration. We conclude that this method is effective for the management of giant partially thrombosed aneurysms of the ICA, especially when direct clipping is difficult.

Peripheral arterial stiffness is associated with higher baseline plasma uric acid: A prospective cohort study.

PubMed

Ding, Xiaohan; Ye, Ping; Wang, Xiaona; Cao, Ruihua; Yang, Xu; Xiao, Wenkai; Zhang, Yun; Bai, Yongyi; Wu, Hongmei

2017-03-01

This prospective cohort study aimed at identifying association between uric acid (UA) and peripheral arterial stiffness. A prospective cohort longitudinal study was performed according to an average of 4.8 years' follow-up. The demographic data, anthropometric parameters, peripheral arterial stiffness (carotid-radial pulse-wave velocity, cr-PWV) and biomarker variables including UA were examined at both baseline and follow-up. Pearson's correlations were used to identify the associations between UA and peripheral arterial stiffness. Further logistic regressions were employed to determine the associations between UA and arterial stiffness. At the end of follow-up, 1447 subjects were included in the analyses. At baseline, cr-PWV ( r  = 0.200, p  < 0.001) was closely associated with UA. Furthermore, the follow-up cr-PWV ( r  = 0.145, p  < 0.001) was also strongly correlated to baseline UA in Pearson's correlation analysis. Multiple regressions also indicated the association between follow-up cr-PWV ( β  = 0.493, p  = 0.013) and baseline UA level. Logistic regressions revealed that higher baseline UA level was an independent predictor of arterial stiffness severity assessed by cr-PWV at follow-up cross-section. Peripheral arterial stiffness is closely associated with higher baseline UA level. Furthermore, a higher baseline UA level is an independent risk factor and predictor for peripheral arterial stiffness.

Comparison of Machine Learning Methods for the Arterial Hypertension Diagnostics

PubMed Central

Belo, David; Gamboa, Hugo

2017-01-01

The paper presents results of machine learning approach accuracy applied analysis of cardiac activity. The study evaluates the diagnostics possibilities of the arterial hypertension by means of the short-term heart rate variability signals. Two groups were studied: 30 relatively healthy volunteers and 40 patients suffering from the arterial hypertension of II-III degree. The following machine learning approaches were studied: linear and quadratic discriminant analysis, k-nearest neighbors, support vector machine with radial basis, decision trees, and naive Bayes classifier. Moreover, in the study, different methods of feature extraction are analyzed: statistical, spectral, wavelet, and multifractal. All in all, 53 features were investigated. Investigation results show that discriminant analysis achieves the highest classification accuracy. The suggested approach of noncorrelated feature set search achieved higher results than data set based on the principal components. PMID:28831239

A new cardiology patient simulator.

PubMed

Takashina, T; Shimizu, M; Katayama, H

1997-01-01

We report a new cardiology patient simulator developed through the application of new digital computer technology, capable of playing back selected physical findings (jugular-venous waves, arterial pulses of carotid, brachial, radial and femoral arteries, and cardiac impulses), as well as cardiac sounds, murmurs and respiratory sounds that have been prerecorded from actual patients. The examining physician uses an ordinary type of stethoscope. Four built-in speakers are located in the human-sized mannequin at the classic auscultatory sites (aortic, pulmonic, tricuspid and mitral). This compact and portable educational apparatus should facilitate medical training in the bedside cardiac examination, of physicians, medical students, nurses and paramedics throughout the world.

A free boundary problem for steady small plaques in the artery and their stability

NASA Astrophysics Data System (ADS)

Friedman, Avner; Hao, Wenrui; Hu, Bei

2015-08-01

Atherosclerosis is a leading cause of death in the United States and worldwide; it originates from a plaque which builds up in the artery. In this paper, we consider a simplified model of plaque growth involving LDL and HDL cholesterols, macrophages and foam cells, which satisfy a coupled system of PDEs with a free boundary, the interface between the plaque and the blood flow. We prove that there exist small radially symmetric stationary plaques and establish a sharp condition that ensures their stability. We also determine necessary and sufficient conditions under which a small initial plaque will shrink and disappear, or persist for all times.

A radial basis function Galerkin method for inhomogeneous nonlocal diffusion

DOE PAGES

Lehoucq, Richard B.; Rowe, Stephen T.

2016-02-01

We introduce a discretization for a nonlocal diffusion problem using a localized basis of radial basis functions. The stiffness matrix entries are assembled by a special quadrature routine unique to the localized basis. Combining the quadrature method with the localized basis produces a well-conditioned, sparse, symmetric positive definite stiffness matrix. We demonstrate that both the continuum and discrete problems are well-posed and present numerical results for the convergence behavior of the radial basis function method. As a result, we explore approximating the solution to anisotropic differential equations by solving anisotropic nonlocal integral equations using the radial basis function method.

Chasing the reflected wave back into the heart: a new hypothesis while the jury is still out

PubMed Central

Codreanu, Ion; Robson, Matthew D; Rider, Oliver J; Pegg, Tammy J; Jung, Bernd A; Dasanu, Constantin A; Clarke, Kieran; Holloway, Cameron J

2011-01-01

Background: Arterial stiffness directly influences cardiac function and is independently associated with cardiovascular risk. However, the influence of the aortic reflected pulse pressure wave on left ventricular function has not been well characterized. The aim of this study was to obtain detailed information on regional ventricular wall motion patterns corresponding to the propagation of the reflected aortic wave on ventricular segments. Methods: Left ventricular wall motion was investigated in a group of healthy volunteers (n = 14, age 23 ± 3 years), using cardiac magnetic resonance navigator-gated tissue phase mapping. The left ventricle was divided into 16 segments and regional wall motion was studied in high temporal detail. Results: Corresponding to the expected timing of the reflected aortic wave reaching the left ventricle, a characteristic “notch” of regional myocardial motion was seen in all radial, circumferential, and longitudinal velocity graphs. This notch was particularly prominent in septal segments adjacent to the left ventricular outflow tract on radial velocity graphs and in anterior and posterior left ventricular segments on circumferential velocity graphs. Similarly, longitudinal velocity graphs demonstrated a brief deceleration in the upward recoil motion of the entire ventricle at the beginning of diastole. Conclusion: These results provide new insights into the possible influence of the reflected aortic waves on ventricular segments. Although the association with the reflected wave appears to us to be unambiguous, it represents a novel research concept, and further studies enabling the actual recording of the pulse wave are required. PMID:21731888

Human health monitoring technology

NASA Astrophysics Data System (ADS)

Kim, Byung-Hyun; Yook, Jong-Gwan

2017-05-01

Monitoring vital signs from human body is very important to healthcare and medical diagnosis, because they contain valuable information about arterial occlusions, arrhythmia, atherosclerosis, autonomous nervous system pathologies, stress level, and obstructive sleep apnea. Existing methods, such as electrocardiogram (ECG) sensor and photoplethysmogram (PPG) sensor, requires direct contact to the skin and it can causes skin irritation and the inconvenience of long-term wearing. For reducing the inconvenience in the conventional sensors, microwave and millimeter-wave sensors have been proposed since 1970s using micro-Doppler effect from one's cardiopulmonary activity. The Doppler radar sensor can remotely detect the respiration and heartbeat up to few meters away from the subject, but they have a multiple subject issue and are not suitable for an ambulatory subject. As a compromise, a noncontact proximity vital sign sensor has been recently proposed and developed. The purpose of this paper is to review the noncontact proximity vital sign sensors for detection of respiration, heartbeat rate, and/or wrist pulse. This sensor basically employs near-field perturbation of radio-frequency (RF) planar resonator due to the proximity of the one's chest or radial artery at the wrist. Various sensing systems based on the SAW filter, phase-locked loop (PLL) synthesizer, reflectometer, and interferometer have been proposed. These self-sustained systems can measure the nearfield perturbation and transform it into DC voltage variation. Consequently, they can detect the respiration and heartbeat rate near the chest of subject and pulse from radial artery at the wrist.

High Spatiotemporal Resolution Dynamic Contrast-Enhanced MR Enterography in Crohn Disease Terminal Ileitis Using Continuous Golden-Angle Radial Sampling, Compressed Sensing, and Parallel Imaging.

PubMed

Ream, Justin M; Doshi, Ankur; Lala, Shailee V; Kim, Sooah; Rusinek, Henry; Chandarana, Hersh

2015-06-01

The purpose of this article was to assess the feasibility of golden-angle radial acquisition with compress sensing reconstruction (Golden-angle RAdial Sparse Parallel [GRASP]) for acquiring high temporal resolution data for pharmacokinetic modeling while maintaining high image quality in patients with Crohn disease terminal ileitis. Fourteen patients with biopsy-proven Crohn terminal ileitis were scanned using both contrast-enhanced GRASP and Cartesian breath-hold (volume-interpolated breath-hold examination [VIBE]) acquisitions. GRASP data were reconstructed with 2.4-second temporal resolution and fitted to the generalized kinetic model using an individualized arterial input function to derive the volume transfer coefficient (K(trans)) and interstitial volume (v(e)). Reconstructions, including data from the entire GRASP acquisition and Cartesian VIBE acquisitions, were rated for image quality, artifact, and detection of typical Crohn ileitis features. Inflamed loops of ileum had significantly higher K(trans) (3.36 ± 2.49 vs 0.86 ± 0.49 min(-1), p < 0.005) and v(e) (0.53 ± 0.15 vs 0.20 ± 0.11, p < 0.005) compared with normal bowel loops. There were no significant differences between GRASP and Cartesian VIBE for overall image quality (p = 0.180) or detection of Crohn ileitis features, although streak artifact was worse with the GRASP acquisition (p = 0.001). High temporal resolution data for pharmacokinetic modeling and high spatial resolution data for morphologic image analysis can be achieved in the same acquisition using GRASP.

Cardiovascular cine imaging and flow evaluation using Fast Interrupted Steady-State (FISS) magnetic resonance.

PubMed

Edelman, Robert R; Serhal, Ali; Pursnani, Amit; Pang, Jianing; Koktzoglou, Ioannis

2018-02-19

Existing cine imaging techniques rely on balanced steady-state free precession (bSSFP) or spoiled gradient-echo readouts, each of which has limitations. For instance, with bSSFP, artifacts occur from rapid through-plane flow and off-resonance effects. We hypothesized that a prototype cine technique, radial fast interrupted steady-state (FISS), could overcome these limitations. The technique was compared with standard cine bSSFP for cardiac function, coronary artery conspicuity, and aortic valve morphology. Given its advantageous properties, we further hypothesized that the cine FISS technique, in combination with arterial spin labeling (ASL), could provide an alternative to phase contrast for visualizing in-plane flow patterns within the aorta and branch vessels. The study was IRB-approved and subjects provided consent. Breath-hold cine FISS and bSSFP were acquired using similar imaging parameters. There was no significant difference in biplane left ventricular ejection fraction or cardiac image quality between the two techniques. Compared with cine bSSFP, cine FISS demonstrated a marked decrease in fat signal which improved conspicuity of the coronary arteries, while suppression of through-plane flow artifact on thin-slice cine FISS images improved visualization of the aortic valve. Banding artifacts in the subcutaneous tissues were reduced. In healthy subjects, dynamic flow patterns were well visualized in the aorta, coronary and renal arteries using cine FISS ASL, even when the slice was substantially thicker than the vessel diameter. Cine FISS demonstrates several benefits for cardiovascular imaging compared with cine bSSFP, including better suppression of fat signal and reduced artifacts from through-plane flow and off-resonance effects. The main drawback is a slight (~ 20%) decrease in temporal resolution. In addition, preliminary results suggest that cine FISS ASL provides a potential alternative to phase contrast techniques for in-plane flow quantification, while enabling an efficient, visually-appealing, semi-projective display of blood flow patterns throughout the course of an artery and its branches.

The Radial Bow following Square Nailing in Radius and Ulna Shaft Fractures in Adults and its Relation to Disability and Function.

PubMed

Dave, M B; Parmar, K D; Sachde, B A

2016-07-01

One of the points made against nailing in radius and ulna shaft fractures has been the loss of radial bow and its impact on function. The aims of the study were to assess the change in magnitude and location of the radial bow in radius and ulna shaft fractures treated with intramedullary square nails and to assess the impact of this change on functional outcome, patient reported disability and the range of motion of the forearm. We measured the magnitude of radial bow and its location in the operated extremity and compared it to the uninjured side in 32 adult patients treated with intramedullary square nailing for radius and ulna shaft fractures at our institute. The mean loss of magnitude of maximum radial bow was 2.18 mm which was statistically significant by both student-T test and Mann-Whitney U test with p value less than 0.01. The location of maximum radial bow shifted distally but was statistically insignificant. The magnitude of maximum radial bow had a negative correlation with DASH score that was statistically insignificant (R=- 0.22, p=0.21). It had a positive, statistically significant correlation to the extent of supination in the operated extremity (R = 0.66, p = 0.0004). A loss of up to 2mm of radial bow did not influence the functional outcome as assessed by criteria reported by Anderson et al. The magnitude of radial bow influenced the supination of the forearm but not the final disability as measured by DASH score. Intramedullary nailing did decrease the magnitude of radial bow but a reduction of up to 2mm did not influence the functional outcome.

The effect of acute maximal exercise on postexercise hemodynamics and central arterial stiffness in obese and normal-weight individuals.

PubMed

Bunsawat, Kanokwan; Ranadive, Sushant M; Lane-Cordova, Abbi D; Yan, Huimin; Kappus, Rebecca M; Fernhall, Bo; Baynard, Tracy

2017-04-01

Central arterial stiffness is associated with incident hypertension and negative cardiovascular outcomes. Obese individuals have higher central blood pressure (BP) and central arterial stiffness than their normal-weight counterparts, but it is unclear whether obesity also affects hemodynamics and central arterial stiffness after maximal exercise. We evaluated central hemodynamics and arterial stiffness during recovery from acute maximal aerobic exercise in obese and normal-weight individuals. Forty-six normal-weight and twenty-one obese individuals underwent measurements of central BP and central arterial stiffness at rest and 15 and 30 min following acute maximal exercise. Central BP and normalized augmentation index (AIx@75) were derived from radial artery applanation tonometry, and central arterial stiffness was obtained via carotid-femoral pulse wave velocity (cPWV) and corrected for central mean arterial pressure (cPWV/cMAP). Central arterial stiffness increased in obese individuals but decreased in normal-weight individuals following acute maximal exercise, after adjusting for fitness. Obese individuals also exhibited an overall higher central BP ( P  <   0.05), with no exercise effect. The increase in heart rate was greater in obese versus normal-weight individuals following exercise ( P  <   0.05), but there was no group differences or exercise effect for AIx@75 In conclusion, obese (but not normal-weight) individuals increased central arterial stiffness following acute maximal exercise. An assessment of arterial stiffness response to acute exercise may serve as a useful detection tool for subclinical vascular dysfunction. © 2017 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.

Patient Versus Physician Variation in Use of Transradial Percutaneous Coronary Intervention.

PubMed

Shamim, Shariq; Tang, Fengming; Safley, David; Jones, Philip; Spertus, John A; Baklanov, Dmitri

2017-06-15

The prevalence of radial access for transradial catheterization remains low in the United States, occurring in only 28% of cases in the National Cardiovascular Data Registry (NCDR) CathPCI. It is unknown whether the low adoption rate has been influenced by patient characteristics or is more operator dependent. In a 10-center study, we compared clinical and demographic characteristics among 323 radial and 1,506 femoral access percutaneous coronary intervention (PCIs) performed by 65 interventionists capable of radial PCI. We created a hierarchical logistic regression model to identify operator and patient characteristics associated with radial PCI and the median rate ratio to quantify the variation across operators. A subset was interviewed to assess health literacy and preferences in shared medical decision making. Radial access was used in 17.7% of patients. Patient factors associated with lower rate of radial PCI were previous PCI (33.4% vs 41.4%, p = 0.008), history of coronary artery bypass graft (8.4% vs 23.0%, p <0.001), and chronic total occlusion PCI (10.2% vs 17.9%, p <0.001). Operator characteristics associated with lower rate of radial PCI are being older, being longer in practice, lower number of publications, and Southern practice location. The range of radial use across operators was 1% to 99% and the median rate ratio was 1.97. Patients with radial access had lower health literacy, as assessed by the Rapid Estimate of Adult Literacy in Medicine Revised (REALM) score (6.6 ± 2.6 vs 7.1 ± 2.0, p = 0.03) but did not differ in their preferences for shared decision making. In conclusion, our study demonstrates a high degree of variability of radial access for PCI among different operators, with few differences in patient characteristics, suggesting that improvement efforts should focus on operators. Copyright © 2017 Elsevier Inc. All rights reserved.

Long-term exposure to airborne particles and arterial stiffness: the Multi-Ethnic Study of Atherosclerosis (MESA).

PubMed

O'Neill, Marie S; Diez-Roux, Ana V; Auchincloss, Amy H; Shen, Mingwu; Lima, João A; Polak, Joseph F; Barr, R Graham; Kaufman, Joel; Jacobs, David R

2011-06-01

Increased arterial stiffness could represent an intermediate subclinical outcome in the mechanistic pathway underlying associations between average long-term pollution exposure and cardiovascular events. We hypothesized that 20 years of exposure to particulate matter (PM) ≤ 2.5 and 10 μm in aerodynamic diameter (PM2.5 and PM10, respectively) would be positively associated with arterial stiffness in 3,996 participants from the Multi-Ethnic Study of Atherosclerosis (MESA) who were seen at six U.S. study sites. We assigned pollution exposure during two decades preceding a clinical exam (2000-2002) using observed PM10 from monitors nearest participants' residences and PM10 and PM2.5 imputed from a space-time model. We examined three log-transformed arterial stiffness outcome measures: Young's modulus (YM) from carotid artery ultrasound and large (C1) and small (C2) artery vessel compliance from the radial artery pulse wave. All associations are expressed per 10 μg/m3 increment in PM and were adjusted for weather, age, sex, race, glucose, triglycerides, diabetes, waist:hip ratio, seated mean arterial pressure, smoking status, pack-years, cigarettes per day, environmental tobacco smoke, and physical activity. C1 and C2 models were further adjusted for heart rate, weight, and height. Long-term average particle exposure was not associated with greater arterial stiffness measured by YM, C1, or C2, and the few associations observed were not robust across metrics and adjustment schemes. Long-term particle mass exposure did not appear to be associated with greater arterial stiffness in this study sample.

Relationship between preoperative radial artery and postoperative arteriovenous fistula blood flow in hemodialysis patients.

PubMed

Sato, Michiko; Io, Hiroaki; Tanimoto, Mitsuo; Shimizu, Yoshio; Fukui, Mitsumine; Hamada, Chieko; Horikoshi, Satoshi; Tomino, Yasuhiko

2012-01-01

It is recommended that arteriovenous fistula (AVF) blood flow should be more than 425 ml/min before cannulation. However, the relationship between preoperative radial artery flow (RAF) and postoperative AVF blood flow has still not been examined. Sixty-one patients with end-stage kidney disease (ESKD) were examined. They had an AVF prepared at Juntendo University Hospital from July 2006 through August 2007. Preoperative RAF and postoperative AVF blood flows were measured by ultrasonography. AVF blood flow gradually increased after the operation. AVF blood flow was significantly correlated with preoperative RAF. When preoperative RAF exceeded 21.4 ml/min, AVF blood flow rose to more than 425 ml/min. The postoperative AVF blood flow in the group with RAF of more than 20 ml/min was significantly higher than that in those with less than 20 ml/min. Preoperative RAF of less than 20 ml/min had a significantly high risk of primary AVF failure within 8 months compared with that of more than 20 ml/min. It appears that measurement of RAF by ultrasonography is useful for estimating AVF blood flow postoperatively and can predict the risk of complications in ESKD patients.

Arterial wave reflections and kidney function decline among persons with preserved estimated glomerular filtration rate: the Multi-Ethnic Study of Atherosclerosis.

PubMed

Hsu, Jeffrey J; Katz, Ronit; Chirinos, Julio A; Jacobs, David R; Duprez, Daniel A; Peralta, Carmen A

2016-05-01

Differences in arterial wave reflections have been associated with increased risk for heart failure and mortality. Whether these measures are also associated with kidney function decline is not well established. Reflection magnitude (RM, defined as the ratio of the backward wave [Pb] to that of the forward wave [Pf]), augmentation index (AIx), and pulse pressure amplification (PPA) were derived from radial tonometry measures among 5232 participants free of cardiovascular disease who were enrolled in the Multiethnic Study of Atherosclerosis. Kidney function was estimated by creatinine and cystatin C measurements, as well as albumin-to-creatinine ratio. We evaluated the associations of Pb, Pf, RM, AIx, and PPA with annualized estimated glomerular filtration rate (eGFR) change and rapid kidney function decline over 5 years, using generalized linear mixed models and logistic regression, respectively. Of the study participants, 48% were male, mean age was 62 years, mean eGFR and median albumin-to-creatinine ratio at baseline were 84 mL/min/1.73 m(2) and 5.3 mg/g, respectively. In demographically adjusted models, both Pb and Pf had similarly strong associations with kidney function decline; compared to those in the lowest tertiles, the persons in the highest tertiles of Pb and Pf had a 1.01 and 0.99 mL/min/1.73 m(2)/year faster eGFR decline, respectively (P < .05). However, these associations were attenuated after adjustment for systolic blood pressure. We found no significant associations between RM, AIx, or PPA and kidney function decline. In conclusion, the reflected and forward wave components were similarly associated with kidney function decline, and these associations were explained by differences in systolic blood pressure. Copyright © 2016 American Society of Hypertension. Published by Elsevier Inc. All rights reserved.

Risk factors for neurological worsening and symptomatic watershed infarction in internal carotid artery aneurysm treated by extracranial-intracranial bypass using radial artery graft.

PubMed

Matsukawa, Hidetoshi; Tanikawa, Rokuya; Kamiyama, Hiroyasu; Tsuboi, Toshiyuki; Noda, Kosumo; Ota, Nakao; Miyata, Shiro; Oda, Jumpei; Takeda, Rihee; Tokuda, Sadahisa; Kamada, Kyousuke

2016-08-01

OBJECT The revascularization technique, including bypass created using the external carotid artery (ECA), radial artery (RA), and M2 portion of middle cerebral artery (MCA), has remained indispensable for treatment of complex aneurysms. To date, it remains unknown whether diameters of the RA, superficial temporal artery (STA), and C2 portion of the internal carotid artery (ICA) and intraoperative MCA blood pressure have influences on the outcome and the symptomatic watershed infarction (WI). The aim of the present study was to evaluate the factors for the symptomatic WI and neurological worsening in patients treated by ECA-RA-M2 bypass for complex ICA aneurysm with therapeutic ICA occlusion. METHODS The authors measured the sizes of vessels (RA, C2, M2, and STA) and intraoperative MCA blood pressure (initial, after ICA occlusion, and after releasing the RA graft bypass) in 37 patients. Symptomatic WI was defined as presence of the following: postoperative new neurological deficits, WI on postoperative diffusion-weighted imaging, and ipsilateral cerebral blood flow reduction on SPECT. Neurological worsening was defined as the increase in 1 or more modified Rankin Scale scores. First, the authors performed receiver operating characteristic curve analysis for continuous variables and the binary end point of the symptomatic WI. The clinical, radiological, and physiological characteristics of patients with and without the symptomatic WI were compared using the log-rank test. Then, the authors compared the variables between patients with and without neurological worsening at discharge and at the 12-month follow-up examination or last hospital visit. RESULTS Symptomatic WI was observed in 2 (5.4%) patients. The mean MCA pressure after releasing the RA graft (< 55 mm Hg; p = 0.017), mean (MCA pressure after releasing the RA graft)/(initial MCA pressure) (< 0.70 mm Hg; p = 0.032), and mean cross-sectional area ratio ([RA/C2 diameter](2) < 0.40 mm [p < 0.0001] and [STA/C2 diameter](2) < 0.044 mm [p < 0.0001]) were related to the symptomatic WI. All preoperatively independent patients remained independent (modified Rankin Scale score < 3). After adjusting for age and sex, left operative side (p = 0.0090 and 0.038) and perforating artery ischemia (p = 0.0050 and 0.022) were related to neurological worsening at discharge (11 [29%] patients) and at the 12-month follow-up or last hospital visit (8 [22%] patients). CONCLUSIONS Results of the present study showed that the vessel diameter and intraoperative MCA pressure had impacts on the symptomatic WI and that operative side and perforating artery ischemia were related to neurological worsening in patients with complex ICA aneurysms treated by ECA-RA-M2 bypass.

47 CFR 22.911 - Cellular geographic service area.

Code of Federal Regulations, 2011 CFR

2011-10-01

... the SAB is calculated as a function of effective radiated power (ERP) and antenna center of radiation...: d is the radial distance in kilometers h is the radial antenna HAAT in meters p is the radial ERP in... the radial distance in kilometers h is the radial antenna HAAT in meters p is the radial ERP in Watts...

The Anterior Interosseus Artery Perforator Flap: Anatomical Dissections and Clinical Study.

PubMed

Panse, Nikhil S; Joshi, Sheetal B; Sahasrabudhe, Parag B; Bahetee, B; Gurude, Pradnya; Chandanwale, Ajay

2017-05-01

Reconstruction of upper extremity deformities continues to be a challenge to the reconstructive surgeon. Various loco regional, distant and free flaps are available for reconstruction. However, each has its own set of advantages and disadvantages. Of the commonly performed local flaps, radial artery forearm flap, and the posterior interosseus artery flap stand out prominently. Recently, perforator propeller flaps have been used for resurfacing the upper extremity. The anterior interosseus artery perforator flap is an uncommonly used and described flap. This study was divided into anatomical study and clinical application in a IV level of evidence. In the anatomical study, five upper extremities were studied. Clinically, 12 patients underwent reconstruction using the anterior interosseus artery perforator flap. Flaps were performed by a single surgeon. A retrospective review of these cases from November 2008 to May 2014 is presented. The anterior interosseus artery perforator was identified in four out of five cadaver limbs. The septocutaneous perforator was in the fifth extensor compartment around 4 cm proximal to the wrist joint. Of the twelve flaps, there was complete necrosis in one flap, and partial necrosis in one flap. The patient with complete necrosis underwent skin grafting at a later date. The wound healed secondarily in case of partial flap necrosis. Anterior interosseus artery perforator flap must be considered as an important reconstructive option in the armamentarium of the plastic surgeon, while managing hand and wrist defects.

Methods and apparatus for determining cardiac output

NASA Technical Reports Server (NTRS)

Cohen, Richard J. (Inventor); Sherman, Derin A. (Inventor); Mukkamala, Ramakrishna (Inventor)

2010-01-01

The present invention provides methods and apparatus for determining a dynamical property of the systemic or pulmonary arterial tree using long time scale information, i.e., information obtained from measurements over time scales greater than a single cardiac cycle. In one aspect, the invention provides a method and apparatus for monitoring cardiac output (CO) from a single blood pressure signal measurement obtained at any site in the systemic or pulmonary arterial tree or from any related measurement including, for example, fingertip photoplethysmography.According to the method the time constant of the arterial tree, defined to be the product of the total peripheral resistance (TPR) and the nearly constant arterial compliance, is determined by analyzing the long time scale variations (greater than a single cardiac cycle) in any of these blood pressure signals. Then, according to Ohm's law, a value proportional to CO may be determined from the ratio of the blood pressure signal to the estimated time constant. The proportional CO values derived from this method may be calibrated to absolute CO, if desired, with a single, absolute measure of CO (e.g., thermodilution). The present invention may be applied to invasive radial arterial blood pressure or pulmonary arterial blood pressure signals which are routinely measured in intensive care units and surgical suites or to noninvasively measured peripheral arterial blood pressure signals or related noninvasively measured signals in order to facilitate the clinical monitoring of CO as well as TPR.

Uteroplacental arterio-venous difference in soluble VEGFR-1 (sFlt-1), but not in soluble endoglin concentrations in preeclampsia.

PubMed

Paasche Roland, M C; Lorentzen, B; Godang, K; Henriksen, T

2012-03-01

The aim was to determine plasma levels of sFlt-1 and sEng on the arterial and venous side of the uteroplacental circulation in preeclamptic patients and healthy controls. Preeclamptic patients had higher arterial concentrations than controls of sFlt-1 (17,450 vs. 5055 pg/ml, p = 0.003) and sEng (68.7 vs. 28.7 ng/ml, p = 0.003). In the preclampsia group sFlt-1 was higher in the uterine vein than in the radial artery (22,450 vs. 17,450 pg/ml, p = 0.005). We found no gradient for sEng. Our results support the hypothesis that excess sFlt-1 at least partly originates in placenta, while excess sEng appears to have a different origin. Copyright © 2012 Elsevier Ltd. All rights reserved.

A Novel Arterial Constitutive Model in a Commercial Finite Element Package: Application to Balloon Angioplasty

PubMed Central

Zhao, Xuefeng; Liu, Yi; Zhang, Wei; Wang, Cong; Kassab, Ghassan S.

2011-01-01

Recently, a novel linearized constitutive model with a new strain measure that absorbs the material nonlinearity was validated for arteries. In this study, the linearized arterial stress-strain relationship is implemented into a finite element method package ANSYS, via the user subroutine USERMAT. The reference configuration is chosen to be the closed cylindrical tube (no-load state) rather than the open sector (zero-stress state). The residual strain is taken into account by analytic calculation and the incompressibility condition is enforced with Lagrange penalty method. Axisymmetric finite element analyses are conducted to demonstrate potential applications of this approach in a complex boundary value problem where angioplasty balloon interacts with the vessel wall. The model predictions of transmural circumferential and compressive radial stress distributions were also validated against an exponential-type Fung model, and the mean error was found to be within 6%. PMID:21689665

Influence of magnetic field on chemically reactive blood flow through stenosed bifurcated arteries

NASA Astrophysics Data System (ADS)

Hossain, Khan Enaet; Haque, Md. Mohidul

2017-06-01

Dynamic response of mass transfer in chemically reactive blood flow through bifurcated arteries under the stenotic condition is numerically studied in the present of a uniform magnetic field. The blood flowing through the artery is assumed an incompressible, fully developed and Newtonian. The nonlinear unsteady flow phenomena are governed by the Navier-Stokes and concentration equations. All these equations together with the appropriate boundary conditions describing the present biomechanical problem are transformed by using a radial transformation and the numerical results are obtained using a finite difference technique. Effects of stenosed bifurcation and externally applied magnetic field on the blood flow with chemical reaction are discussed with the help of graph. All the flow characteristics are found to be affected by the presence of chemical reaction and exposure of magnetic field of different intensities. Finally some important findings of the problem are concluded in this work.

Intraluminal ultrasound guidance of transverse laser coronary atherectomy

NASA Astrophysics Data System (ADS)

Aretz, H. Thomas; Martinelli, Michael A.; LeDet, Earl G.; Sedlacek, Tomas; Hatch, G. F.; Gregg, Richard E.

1990-07-01

A coronary laser atherectomy system combining laser delivery and ultrasonic imaging capability is described. The system is being developed by Intra-Sonix, Inc. to treat severe stenoses. The imaging system provides the clinician with the guidance needed to remove substantial plaque without perforation. The ultrasound transducers and laser optics are mounted in a small (less than 4 F), flexible catheter, that is deliverable over a standard guidewire (0.016 inch). The laser and ultrasound beams are directed at the artery wall to permit debulking of lesions and ultrasonic depth profiling of the tissue structure throughout the thickness of the artery. This allows the physician to determine the level of therapy to be applied and to monitor the plaque removal as the therapy progresses. The precise location of the ultrasound and laser beams in the artery is determined by a navigation system. Navigation data are processed electronically in conjunction with ultrasound data to produce real-time cross-sectional and longitudinal images of the artery wall at selected locations, which are updated as the catheter progresses through the vessel lumen. Results of in vitro tests on human atherosclerotic arteries and early in vivo experiments in a canine-human xenograft model showing image construction and radial laser delivery are discussed.

Arterial injuries in civilian practice in Lagos, Nigeria.

PubMed

Thomas, M O; Giwa, S O; Adekoya-Cole, T O

2005-12-01

This is a retrospective study of patients managed at the Lagos University Teaching Hospital for peripheral arterial injuries from January 1995 to April 2003. The aim was to study the pattern of peripheral arterial injuries in Lagos. Nigeria and to look at the outcome of management and see what improvements could be made in future. Data was collated from case notes of patients, operation register in theatre and admission and discharge books from the surgical wards and the data bank of consultants involved in patients' management. Forty-one patients. 37 males and 4 females. were treated within the study period (M:F ratio of 9:1). Twenty three patients (56.1%) suffered gunshot injuries during armed robbery attacks while 9 patients (22.0%) had stab injuries in civilian violence. Twenty-one patients (3 with gunshot injuries and 18 non gunshot penetrating injuries) were managed by direct suturing of vessels. Eight patients had prosthetic graft interposition while 2 patients had reversed saphenous vein grafts. Two patients had the superficial branches of their radial arteries tied up at the wrist. Gun shot injuries from armed robbery attack was the commonest cause of peripheral arterial injuries in this environment during the period of study.

Kv channel subunits that contribute to voltage-gated K+ current in renal vascular smooth muscle.

PubMed

Fergus, Daniel J; Martens, Jeffrey R; England, Sarah K

2003-03-01

The rat renal arterial vasculature displays differences in K(+) channel current phenotypes along its length. Small arcuate to cortical radial arteries express a delayed rectifier phenotype, while the predominant Kv current in larger arcuate and interlobar arteries is composed of both transient and sustained components. We sought to determine whether Kvalpha subunits in the rat renal interlobar and arcuate arteries form heterotetramers, which may account for the unique currents, and whether modulatory Kvbeta subunits are present in renal vascular smooth muscle cells. RT-PCR indicated the presence of several different Kvalpha subunit isoform transcripts. Co-immunoprecipitation with immunoblotting and immunohistochemical evidence suggests that a portion of the K(+) current phenotype is a heteromultimer containing delayed-rectifier Kv1.2 and A-type Kv1.4 channel subunits. RT-PCR and immunoblot analyses also demonstrated the presence of both Kvbeta1.2 and Kvbeta1.3 in renal arteries. These results suggest that heteromultimeric formation of Kvalpha subunits and the presence of modulatory Kvbeta subunits are important factors in mediating Kv currents in the renal microvasculature and suggest a potentially critical role for these channel subunits in blood pressure regulation.

Arterial Structure and Function in Mild Primary Hyperparathyroidism Is Not Directly Related to Parathyroid Hormone, Calcium, or Vitamin D

PubMed Central

Ring, Margareta; Farahnak, Parastou; Gustavsson, Tomas; Nilsson, Inga-Lena; Eriksson, Maria J.; Caidahl, Kenneth

2012-01-01

Objective Elevated levels of calcium and parathyroid hormone (PTH), characteristics of primary hyperparathyroidism (PHPT), may be associated with cardiovascular morbidity and mortality in the general population. We evaluated the possible vascular effects of these risk factors in patients with mild PHPT by using standard methods and new imaging techniques. Design A prospective case-control study. Subjects and Methods Forty-eight patients with mild PHPT without any known cardiovascular risk factors were studied at baseline and at one year after parathyroidectomy (PTX) in comparison with 48 healthy age- and gender-matched controls. We measured biochemical variables, augmentation index (AIx), aortic pulse wave velocity (PWVao), radial (IMTrad) and common carotid artery (IMTcca) intima media thicknesses, and the grayscale median (IM-GSM) of the latter. Results No significant differences were observed between PHPT patients and controls at baseline for AIx (28.6±12.2 vs. 27.7±12.8%), IMTrad (0.271±0.060 vs. 0.255±0.053 mm), IMTcca (0.688±0.113 vs. 0.680±0.135 mm), or IM-GSM (82.3±17.2 vs. 86.5±15.3), while PWVao was slightly higher in patients (8.68±1.50 vs. 8.13±1.55, p<0.05). Systolic blood pressure (SBP), calcium, and PTH were higher in patients compared with controls, and decreased after PTX, while vitamin D was lower in patients and increased after PTX. While AIx, PWVao, IMTrad, and IMTcca were related to SBP, neither correlated to vitamin D levels. Only PWVao correlated weakly to plasma PTH (r = 0.29, p<0.01) and ionized calcium (r = 0.22, p<0.05) but showed no relation when age and SBP were adjusted for. Conclusion We found normal arterial function despite high calcium, PTH, and low vitamin D levels, in patients with mild PHPT without cardiovascular risk factors. The cardiovascular risk associated with low vitamin D and/or high PTH and calcium levels may be explained by their coupling to blood pressure and other risk factors rather than direct effects on arterial structure. PMID:22815708

Radial q-space sampling for DSI.

PubMed

Baete, Steven H; Yutzy, Stephen; Boada, Fernando E

2016-09-01

Diffusion spectrum imaging (DSI) has been shown to be an effective tool for noninvasively depicting the anatomical details of brain microstructure. Existing implementations of DSI sample the diffusion encoding space using a rectangular grid. Here we present a different implementation of DSI whereby a radially symmetric q-space sampling scheme for DSI is used to improve the angular resolution and accuracy of the reconstructed orientation distribution functions. Q-space is sampled by acquiring several q-space samples along a number of radial lines. Each of these radial lines in q-space is analytically connected to a value of the orientation distribution functions at the same angular location by the Fourier slice theorem. Computer simulations and in vivo brain results demonstrate that radial diffusion spectrum imaging correctly estimates the orientation distribution functions when moderately high b-values (4000 s/mm2) and number of q-space samples (236) are used. The nominal angular resolution of radial diffusion spectrum imaging depends on the number of radial lines used in the sampling scheme, and only weakly on the maximum b-value. In addition, the radial analytical reconstruction reduces truncation artifacts which affect Cartesian reconstructions. Hence, a radial acquisition of q-space can be favorable for DSI. Magn Reson Med 76:769-780, 2016. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

Regional metabolic liver function measured in patients with cirrhosis by 2-[¹⁸F]fluoro-2-deoxy-D-galactose PET/CT.

PubMed

Sørensen, Michael; Mikkelsen, Kasper S; Frisch, Kim; Villadsen, Gerda E; Keiding, Susanne

2013-06-01

There is a clinical need for methods that can quantify regional hepatic function non-invasively in patients with cirrhosis. Here we validate the use of 2-[(18)F]fluoro-2-deoxy-d-galactose (FDGal) PET/CT for measuring regional metabolic function to this purpose, and apply the method to test the hypothesis of increased intrahepatic metabolic heterogeneity in cirrhosis. Nine cirrhotic patients underwent dynamic liver FDGal PET/CT with blood samples from a radial artery and a liver vein. Hepatic blood flow was measured by indocyanine green infusion/Fick's principle. From blood measurements, hepatic systemic clearance (Ksyst, Lblood/min) and hepatic intrinsic clearance (Vmax/Km, Lblood/min) of FDGal were calculated. From PET data, hepatic systemic clearance of FDGal in liver parenchyma (Kmet, mL blood/mL liver tissue/min) was calculated. Intrahepatic metabolic heterogeneity was evaluated in terms of coefficient-of-variation (CoV, %) using parametric images of Kmet. Mean approximation of Ksyst to Vmax/Km was 86% which validates the use of FDGal as PET tracer of hepatic metabolic function. Mean Kmet was 0.157 mL blood/mL liver tissue/min, which was lower than 0.274 mL blood/mL liver tissue/min, previously found in healthy subjects (p<0.001), in accordance with decreased metabolic function in cirrhotic livers. Mean CoV for Kmet in liver tissue was 24.4% in patients and 14.4% in healthy subjects (p<0.0001). The degree of intrahepatic metabolic heterogeneity correlated positively with HVPG (p<0.05). A 20-min dynamic FDGal PET/CT with arterial sampling provides an accurate measure of regional hepatic metabolic function in patients with cirrhosis. This is likely to have clinical implications for the assessment of patients with liver disease as well as treatment planning and monitoring. Copyright © 2013 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

Free vibrations and buckling analysis of laminated plates by oscillatory radial basis functions

NASA Astrophysics Data System (ADS)

Neves, A. M. A.; Ferreira, A. J. M.

2015-12-01

In this paper the free vibrations and buckling analysis of laminated plates is performed using a global meshless method. A refined version of Kant's theorie which accounts for transverse normal stress and through-the-thickness deformation is used. The innovation is the use of oscillatory radial basis functions. Numerical examples are performed and results are presented and compared to available references. Such functions proved to be an alternative to the tradicional nonoscillatory radial basis functions.

Mismatch between stiffness in elastic and muscular arteries as a predictor of vascular calcification in dialysis patients.

PubMed

Laucyte-Cibulskiene, Agne; Petraviciute, Modesta; Gudynaite, Migle; Gumbys, Liutauras; Valanciene, Dileta; Galiauskiene, Kristina; Ryliskyte, Ligita; Rimsevicius, Laurynas; Miglinas, Marius; Strupas, Kestutis

2018-04-01

Vascular calcification is one of the risk factors for arterial stiffness in patients with chronic kidney disease. We hypothesized that a mismatch between elastic and muscular arteries, represented as pulse wave velocity (PWV) ratio, could depict the extent of vascular calcification in end-stage renal disease. We also aimed to compare the predictive PWV ratio value to other factors possibly related to vascular calcification in dialysis population. In this cross-sectional study, in 60 chronic dialysis patients without previous cerebrovascular events, cardiovascular disease and events or clinically evident peripheral artery disease (ankle-brachial index >0.9), carotid-femoral and carotid-radial PWV as well as central hemodynamic parameters were measured by applanation tonometry (SphygmoCor). The PWV ratio using carotid-femoral PWV divided by carotid-radial PWV was calculated. Each patient underwent blood tests and chest X-ray for aortic arch calcification scoring. Two experienced radiologists blinded to patient's medical data evaluated chest X-rays (Cohen's kappa coefficient 0.76) and calculated how many sectors were calcified (Ogawa et al. in Hemodial Int 13:301-306, 2009). Differently scored chest X-rays were repeatedly reviewed and a consensus was reached. The study population consisted of 31 (51.7%) males and 29 (48.3%) females, mean age 52.73 ± 13.76 years. Increased risk for aortic arch calcification was associated with higher PWV ratio even after adjustment for age, height, heart rate, ferritin level and C-reactive protein level (OR 2.59E+04, 95% CI 2.43E+01, 2.65E+09, p = 0.021). PWV ratio together with above-mentioned variables could predict the presence of aortic arch calcification with specificity of 93% (95% CI 78, 99%) and sensitivity of 53% (95% CI 34, 72%). The elastic and muscular arteries' stiffness mismatch was strongly associated with the extent of aortic arch calcification in this dialysis population and had better calcification predictive value compared to other demographic, hemodynamic and biochemical markers.

Complications of operative treatment of injuries of peripheral arteries.

PubMed

Velinovic, M M; Davidovic, B L; Lotina, I S; Vranes, R M; Djukic, L P; Arsov, J V; Ristic, V M; Kocica, J M; Petrovic, L P

2000-06-01

In 1991 and 1992, a total of 97 patients with 106 peripherial arterial injuries underwent surgery at the Institute for Cardiovascular Diseases, Clinical Centre of Serbia. Civilian injuries accounted for 53 (54.6%) patients (94.3% males, age range: 16-63 yr, mean: 35.2), and 44 patients had war injuries (93.2% males, age range: 19-61 yr, mean: 34.8). The injuries affected the superfitial femoral artery in 31 (29.24%); the popliteal artery in 28 (26.41%); the brachial artery in 17 (16.04%); the posterior tibial artery in 6 (5.66%); the axillary artery in 5 (4.72%); the anterior tibial artery in 5 (4.72%); the tibioperoneal trunk in 4 (3. 77%); the common femoral artery in 4 (3.77%); the external iliac artery in 2 (1.89%); the profound femoral artery in 2 (1.89%); the radial artery in 1 (0.94%); and ulnar artery in 1 (0.94%).A total of 98 reconstructive procedures were used to treat these patients. Graft interposition carried out in 50 (51.02%); by pass in 25 (25. 51%); end-to-end anastomosis in 9 (9.18%); suture in 8 (8.16%); ligation in 4 (4.08%); and patch-angioplasty in 2 (2.04%). Primary reconstruction of injured arteries was performed in 72.2% and secondary repair in 27.8% cases. Infection developed in 51 (52.57%) patients, and it was significantly (P<0.05) more common in the war injuries (70.45%) and in secondary repairs (88.89%). The presence of associated lesions (69.56%) was also correlated with a greater rate of infection. Amputation was necessary in 21 (21.65%) of our patients, and was significantly (P<0.05) more often performed after secondary (44.44%) than primary operations (12.86%) and in the presence of associated injuries (32.61%).

A registry-based randomized trial comparing radial and femoral approaches in women undergoing percutaneous coronary intervention: the SAFE-PCI for Women (Study of Access Site for Enhancement of PCI for Women) trial.

PubMed

Rao, Sunil V; Hess, Connie N; Barham, Britt; Aberle, Laura H; Anstrom, Kevin J; Patel, Tejan B; Jorgensen, Jesse P; Mazzaferri, Ernest L; Jolly, Sanjit S; Jacobs, Alice; Newby, L Kristin; Gibson, C Michael; Kong, David F; Mehran, Roxana; Waksman, Ron; Gilchrist, Ian C; McCourt, Brian J; Messenger, John C; Peterson, Eric D; Harrington, Robert A; Krucoff, Mitchell W

2014-08-01

This study sought to determine the effect of radial access on outcomes in women undergoing percutaneous coronary intervention (PCI) using a registry-based randomized trial. Women are at increased risk of bleeding and vascular complications after PCI. The role of radial access in women is unclear. Women undergoing cardiac catheterization or PCI were randomized to radial or femoral arterial access. Data from the CathPCI Registry and trial-specific data were merged into a final study database. The primary efficacy endpoint was Bleeding Academic Research Consortium type 2, 3, or 5 bleeding or vascular complications requiring intervention. The primary feasibility endpoint was access site crossover. The primary analysis cohort was the subgroup undergoing PCI; sensitivity analyses were conducted in the total randomized population. The trial was stopped early for a lower than expected event rate. A total of 1,787 women (691 undergoing PCI) were randomized at 60 sites. There was no significant difference in the primary efficacy endpoint between radial or femoral access among women undergoing PCI (radial 1.2% vs. 2.9% femoral, odds ratio [OR]: 0.39; 95% confidence interval [CI]: 0.12 to 1.27); among women undergoing cardiac catheterization or PCI, radial access significantly reduced bleeding and vascular complications (0.6% vs. 1.7%; OR: 0.32; 95% CI: 0.12 to 0.90). Access site crossover was significantly higher among women assigned to radial access (PCI cohort: 6.1% vs. 1.7%; OR: 3.65; 95% CI: 1.45 to 9.17); total randomized cohort: (6.7% vs. 1.9%; OR: 3.70; 95% CI: 2.14 to 6.40). More women preferred radial access. In this pragmatic trial, which was terminated early, the radial approach did not significantly reduce bleeding or vascular complications in women undergoing PCI. Access site crossover occurred more often in women assigned to radial access. (SAFE-PCI for Women; NCT01406236). Copyright © 2014 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

[Development of a continuous blood pressure monitoring and recording system].

PubMed

Zhang, Yang; Li, Yong; Gao, Shumei; Song, Yilin

2012-09-01

A small experimental system is constructed with working principle of continuous blood pressure monitoring based on the volume compensation method. The preliminary experimental results show that the system can collect blood pressure signals at the radial artery effectively. The digital PID algorithm can track the variation of blood pressure. And the accuracy of continuous blood pressure detecting achieve the level of same kind of product.

A Clinical Study of the Pulse Wave Characteristics at the Three Pulse Diagnosis Positions of Chon, Gwan and Cheok

PubMed Central

Jeon, Young J.; Kim, Jaeuk U.; Lee, Hae J.; Lee, Jeon; Ryu, Hyun H.; Lee, Yu J.; Kim, Jong Y.

2011-01-01

In this work, we analyze the baseline, signal strength, aortic augmentation index (AIx), radial AIx, time to reflection and P_T2 at Chon, Gwan, and Cheok, which are the three pulse diagnosis positions in Oriental medicine. For the pulse measurement, we used the SphygmoCor apparatus, which has been widely used for the evaluation of the arterial stiffness at the aorta. By two-way repeated measures analysis of variance, we tested two independent measurements for repeatability and investigated their mean differences among Chon, Gwan and Cheok. To characterize further the parameters that were shown to be different between each palpation position, we carried out Duncan's test for the multiple comparisons. The baseline and signal strength were statistically different (P < .05) among Chon, Gwan and Cheok, respectively, which supports the major hypothesis of Oriental medicine that all of the three palpation positions contain different clinical information. On the other hand, aortic AIx and time to reflection were found to be statistically different between Chon and the others, and radial AIx and P_T2 did not show any difference between pulse positions. In the clinical sense, however, the aortic AIx at each palpation position was found to fall within the 90% confidence interval of normal arterial compliance. The results of the multiple comparisons indicate that the parameters of arterial stiffness were independent of the palpation positions. This work is the first attempt to characterize quantitatively the pulse signals at Chon, Gwan and Cheok with some relevant parameters extracted from the SphygmoCor apparatus. PMID:19789213

Feasibility and safety of elective transradial coronary intervention in Asian females.

PubMed

Maddury, Jyotsna; Kaushik, Manu; Madhavapeddi, Aditya; Babu, Srinivas; Kumar, Narendra; Varma, J L N; Alla, Venkata

2011-03-01

Transradial access for angioplasty and percutaneous intervention (PCI) has become more popular across the world due to lower risk of bleeding and better patient comfort. It has been shown to be effective and feasible in the Western population. However, there is a relative paucity of similar data for small-statured females, especially from Asian countries. Given the increased theoretical risk of local complications due to smaller-sized radial arteries in such females, feasibility and safety of transradial PCI (rPCI) needs to be better established in this group. We present observational data for rPCI from a 3-year period at a single tertiary care center in South Asia. Data were collected on all female patients who underwent rPCI from January 2005 to December 2007. Primary outcomes assessed were procedure failure rate and complication rate. Secondary outcomes included death, recurrence of myocardial infarction, anginal symptoms or other complaints. Outcomes were recorded post-procedurally in the hospital and after discharge for up to 6 months. A total of 93 patients were included for final data analysis. Average patient age was 57.5 ± 10.3 years, with average height of 151.7 ± 8.4 cm and average weight of 58.1 ± 12.5 kg. Seventy patients (75.3%) underwent angioplasty or percutaneous intervention (PCI) for ACS and 23 (24.7%) for chronic stable angina refractory to medical therapy. A total of 118 lesions were treated in 90 patients. Ninety-one lesions (77.1%) were classified as Type B2 and Type C according to modified American College of Cardiology/American Heart Association lesion morphology criteria. Three cases of procedure failure accounted for a failure rate of 3.23%. No specified complications were noted in any of the patients. At 6-month follow-up, no deaths were observed. Two patients developed acute myocardial infarction and 16 patients (17.7%) had recurrence of anginal symptoms. Radial artery angioplasty and stenting is feasible and safe in Asian females. Increased theoretical risk of complication due to small-sized radial arteries in this subgroup is unlikely to be true. Success rates are likely to be good even with complex coronary inventions performed with transradial access.

Self-Powered Real-Time Arterial Pulse Monitoring Using Ultrathin Epidermal Piezoelectric Sensors.

PubMed

Park, Dae Yong; Joe, Daniel J; Kim, Dong Hyun; Park, Hyewon; Han, Jae Hyun; Jeong, Chang Kyu; Park, Hyelim; Park, Jung Gyu; Joung, Boyoung; Lee, Keon Jae

2017-10-01

Continuous monitoring of an arterial pulse using a pressure sensor attached on the epidermis is an important technology for detecting the early onset of cardiovascular disease and assessing personal health status. Conventional pulse sensors have the capability of detecting human biosignals, but have significant drawbacks of power consumption issues that limit sustainable operation of wearable medical devices. Here, a self-powered piezoelectric pulse sensor is demonstrated to enable in vivo measurement of radial/carotid pulse signals in near-surface arteries. The inorganic piezoelectric sensor on an ultrathin plastic achieves conformal contact with the complex texture of the rugged skin, which allows to respond to the tiny pulse changes arising on the surface of epidermis. Experimental studies provide characteristics of the sensor with a sensitivity (≈0.018 kPa -1 ), response time (≈60 ms), and good mechanical stability. Wireless transmission of detected arterial pressure signals to a smart phone demonstrates the possibility of self-powered and real-time pulse monitoring system. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Zero-stress states of human pulmonary arteries and veins.

PubMed

Huang, W; Yen, R T

1998-09-01

The zero-stress states of the pulmonary arteries and veins from order 3 to order 9 were determined in six normal human lungs within 15 h postmortem. The zero-stress state of each vessel was obtained by cutting the vessel transversely into a series of short rings, then cutting each ring radially, which caused the ring to spring open into a sector. Each sector was characterized by its opening angle. The mean opening angle varied between 92 and 163 degrees in the arterial tree and between 89 and 128 degrees in the venous tree. There was a tendency for opening angles to increase as the sizes of the arteries and veins increased. We computed the residual strains based on the experimental measurements and estimated the residual stresses according to Hooke's law. We found that the inner wall of a vessel at the state in which the internal pressure, external pressure, and longitudinal stress are all zero was under compression and the outer wall was in tension, and that the magnitude of compressive stress was greater than the magnitude of tensile stress.

New approaches to prevention and treatment of radial artery graft vasospasm.

PubMed

Cable, D G; Caccitolo, J A; Pearson, P J; O'Brien, T; Mullany, C J; Daly, R C; Orszulak, T A; Schaff, H V

1998-11-10

There has been renewed interest in radial artery (RA) conduits for coronary artery bypass because of the relative resistance of arterial grafts to atherosclerosis compared with autogenous vein grafts. Although improved drug therapy for arterial spasm is now available, vasospasm still occurs in at least 5% to 10% of RA grafts. We systematically evaluated the effectiveness of calcium channel blockers and organic nitrates for inhibition or reversal of RA contraction in vitro. Additionally, we investigated the efficacy of novel gene therapy with endothelial nitric oxide synthase (eNOS) to inhibit RA contractions. Segments of RA from 28 patients undergoing coronary artery bypass grafting were mounted in organ chambers. In control experiments, KCl (5 to 50 mmol/L) produced dose-dependent increases in tension (maximum tension, 14.3 +/- 3.0 g, n = 7). Addition of diltiazem or verapamil had no significant effect on KCl contraction (128 +/- 36% and 88 +/- 24% control, respectively); however, nifedipine markedly inhibited KCl contraction (27 +/- 4% control, P = 0.005). Norepinephrine (NE, 10(-9) to 10(-4) M) produced dose-dependent increases in tension (maximum tension, 15.7 +/- 2.7 g in control rings, n = 8). Diltiazem and verapamil pretreatment had no significant effect on NE contraction (103 +/- 14% and 90 +/- 14% control, respectively); nifedipine significantly inhibited NE contraction (70 +/- 11% control, P = 0.02). Isosorbide dinitrate and nitroglycerin markedly inhibited KCl contractions (47 +/- 9% and 30 +/- 8% of controls, n = 6) and NE contractions (42 +/- 10% and 31 +/- 9% of controls, n = 6). Nifedipine, isosorbide, and nitroglycerin were further evaluated for the ability to reverse an established contraction (KCl 40 mmol/L); nitroglycerin was most effective in reversing RA contraction. In separate experiments, RA underwent adenoviral-mediated gene transfer with vehicle, Escherichia coli beta-galactosidase, or eNOS (eNOS, 10(10) PFU/mL x 1 hour). Transgene expression was confirmed by beta-galactosidase activity and eNOS immunohistochemistry after 40 hours of ex vivo incubation. Immunohistochemistry demonstrated recombinant NOS in adenovirus encoding bovine eNOS (Ad.CMVeNOS) RA only. Ad.CMVeNOS arteries contracted only 46.6 +/- 13.7% of controls to KCl (n = 5) and 48.2 +/- 11.4% of controls to prostaglandin F2 alpha a (10(-9) to 10(-6) M, n = 5). Diltiazem, which is used empirically to prevent RA vasospasm, had little effect on human RA contractions (receptor-independent and receptor-dependent). Organic nitrates inhibited and reversed RA contractions. Adenoviral transfer of NOS suggests that future clinical application of gene therapy may play an important role in prevention of RA vasospasm.

Radial basis function neural networks applied to NASA SSME data

NASA Technical Reports Server (NTRS)

Wheeler, Kevin R.; Dhawan, Atam P.

1993-01-01

This paper presents a brief report on the application of Radial Basis Function Neural Networks (RBFNN) to the prediction of sensor values for fault detection and diagnosis of the Space Shuttle's Main Engines (SSME). The location of the Radial Basis Function (RBF) node centers was determined with a K-means clustering algorithm. A neighborhood operation about these center points was used to determine the variances of the individual processing notes.

Wave intensity analysis in mice: an ultrasound-based study in the abdominal aorta and common carotid artery

NASA Astrophysics Data System (ADS)

Di Lascio, N.; Kusmic, C.; Stea, F.; Faita, F.

2017-03-01

Wave Intensity Analysis (WIA) can provide parameters representative of the interaction between the vascular network and the heart. It has been already demonstrated that WIA-derived biomarkes have a quantitative physiological meaning. Aim of this study was to develop an image process algorithm for performing non-invasive WIA in mice and correlate commonly used cardiac function parameters with WIA-derived indexes. Sixteen wild-type male mice (8 weeks-old) were imaged with high-resolution ultrasound (Vevo 2100). Abdominal aorta and common carotid pulse wave velocities (PWVabd, PWVcar) were obtained processing B-Mode and PW-Doppler images and employed to assess WIA. Amplitudes of the first (W1abd, W1car) and the second (W2abd, W2car) local maxima and minimum (Wbabd,Wbcar) were evaluated; areas under the negative part of the curve were also calculated (NAabd, NAcar). Cardiac output (CO), ejection fraction (EF) fractional shortening (FS) and stroke volume (SV) were estimated; strain analysis provided strain and strain rate values for longitudinal, radial and circumferential directions (LS, LSR, RS, RSR, CS, CSR). Isovolumetric relaxation time (IVRT) was calculated from mitral inflow PW-Doppler images; IVRT values were normalized for cardiac cycle length. W1abd was correlated with LS (R=0.65) and LSR (R=0.59), while W1car was correlated with CO (R=0.58), EF (R=0.72), LS (R=0.65), LSR (R=0.89), CS (R=0.71), CSR (R=0.70). Both W2abd and W2car were not correlated with IVRT. Carotid artery WIA-derived parameters are more representative of cardiac function than those obtained from the abdominal aorta. The described US-based method can provide information about cardiac function and cardio-vascular interaction simply studying a single vascular site.

The First Experience of Triple Nerve Transfer in Proximal Radial Nerve Palsy.

PubMed

Emamhadi, Mohammadreza; Andalib, Sasan

2018-01-01

Injury to distal portion of posterior cord of brachial plexus leads to palsy of radial and axillary nerves. Symptoms are usually motor deficits of the deltoid muscle; triceps brachii muscle; and extensor muscles of the wrist, thumb, and fingers. Tendon transfers, nerve grafts, and nerve transfers are options for surgical treatment of proximal radial nerve palsy to restore some motor functions. Tendon transfer is painful, requires a long immobilization, and decreases donor muscle strength; nevertheless, nerve transfer produces promising outcomes. We present a patient with proximal radial nerve palsy following a blunt injury undergoing triple nerve transfer. The patient was involved in a motorcycle accident with complete palsy of the radial and axillary nerves. After 6 months, on admission, he showed spontaneous recovery of axillary nerve palsy, but radial nerve palsy remained. We performed triple nerve transfer, fascicle of ulnar nerve to long head of the triceps branch of radial nerve, flexor digitorum superficialis branch of median nerve to extensor carpi radialis brevis branch of radial nerve, and flexor carpi radialis branch of median nerve to posterior interosseous nerve, for restoration of elbow, wrist, and finger extensions, respectively. Our experience confirmed functional elbow, wrist, and finger extensions in the patient. Triple nerve transfer restores functions of the upper limb in patients with debilitating radial nerve palsy after blunt injuries. Copyright © 2017 Elsevier Inc. All rights reserved.

Therapeutic strategies for patients with micropenis or penile dysmorphic disorder.

PubMed

Kayes, Oliver; Shabbir, Majid; Ralph, David; Minhas, Suks

2012-09-01

Micropenis in adults is defined as a stretched length of <7.5 cm. Many aetiologies exist, including congenital and endocrinological causes as well as pathological conditions, such as penile lichen sclerosus, trauma and genital cancer. The resulting reduction in functional penile length can lead to considerable psychosexual morbidity. Furthermore, the subset of patients with micropenis who also suffer from penile dysmorphic disorder require careful and intensive psychological counselling. Corrective surgery for micropenis can be performed in patients with realistic expectations. Total phalloplasty using radial-artery-based forearm skin flaps can offer restoration of normal penile length in selected patients. More-conservative surgical techniques to improve length or girth are limited by minimal enhancement but associated with a significantly lower rate of complications and comorbidity compared to total phalloplasty. Emerging tissue engineering techniques might represent a suitable alternative to penile replacement surgery in the future.

Assessment of dyssynchronous wall motion during acute myocardial ischemia using velocity vector imaging.

PubMed

Masuda, Kasumi; Asanuma, Toshihiko; Taniguchi, Asuka; Uranishi, Ayumi; Ishikura, Fuminobu; Beppu, Shintaro

2008-03-01

The purpose of this study was to investigate the diagnostic value of velocity vector imaging (VVI) for detecting acute myocardial ischemia and whether VVI can accurately demonstrate the spatial extent of ischemic risk area. Using a tracking algorithm, VVI can display velocity vectors of regional wall motion overlaid onto the B-mode image and allows the quantitative assessment of myocardial mechanics. However, its efficacy for diagnosing myocardial ischemia has not been evaluated. In 18 dogs with flow-limiting stenosis and/or total occlusion of the coronary artery, peak systolic radial velocity (V(SYS)), radial velocity at mitral valve opening (V(MVO)), peak systolic radial strain, and the percent change in wall thickening (%WT) were measured in the normal and risk areas and compared to those at baseline. Sensitivity and specificity for detecting the stenosis and occlusion were analyzed in each parameter. The area of inward velocity vectors at mitral valve opening (MVO) detected by VVI was compared to the risk area derived from real-time myocardial contrast echocardiography (MCE). Twelve image clips were randomly selected from the baseline, stenosis, and occlusions to determine the intra- and inter-observer agreement for the VVI parameters. The left circumflex coronary flow was reduced by 44.3 +/- 9.0% during stenosis and completely interrupted during occlusion. During coronary artery occlusion, inward motion at MVO was observed in the risk area. Percent WT, peak systolic radial strain, V(SYS), and V(MVO) changed significantly from values at baseline. During stenosis, %WT, peak systolic radial strain, and V(SYS) did not differ from those at baseline; however, V(MVO) was significantly increased (-0.12 +/- 0.60 cm/s vs. -0.96 +/- 0.55 cm/s, p = 0.015). Sensitivity and specificity of V(MVO) for detecting ischemia were superior to those of other parameters. The spatial extent of inward velocity vectors at MVO correlated well with that of the risk area derived from MCE (r = 0.74, p < 0.001 with a linear regression). The assessment of VVI at MVO permits easy detection of dyssynchronous wall motion during acute myocardial ischemia that cannot be diagnosed by conventional measurement of systolic wall thickness. The spatial extent of inward motion at MVO suggests the size of the risk area.

The Anterior Interosseus Artery Perforator Flap: Anatomical Dissections and Clinical Study

PubMed Central

Panse, Nikhil S; Joshi, Sheetal B; Sahasrabudhe, Parag B; Bahetee, B; Gurude, Pradnya; Chandanwale, Ajay

2017-01-01

BACKGROUND Reconstruction of upper extremity deformities continues to be a challenge to the reconstructive surgeon. Various loco regional, distant and free flaps are available for reconstruction. However, each has its own set of advantages and disadvantages. Of the commonly performed local flaps, radial artery forearm flap, and the posterior interosseus artery flap stand out prominently. Recently, perforator propeller flaps have been used for resurfacing the upper extremity. The anterior interosseus artery perforator flap is an uncommonly used and described flap. METHODS This study was divided into anatomical study and clinical application in a IV level of evidence. In the anatomical study, five upper extremities were studied. Clinically, 12 patients underwent reconstruction using the anterior interosseus artery perforator flap. Flaps were performed by a single surgeon. A retrospective review of these cases from November 2008 to May 2014 is presented. RESULTS The anterior interosseus artery perforator was identified in four out of five cadaver limbs. The septocutaneous perforator was in the fifth extensor compartment around 4 cm proximal to the wrist joint. Of the twelve flaps, there was complete necrosis in one flap, and partial necrosis in one flap. The patient with complete necrosis underwent skin grafting at a later date. The wound healed secondarily in case of partial flap necrosis. CONCLUSION Anterior interosseus artery perforator flap must be considered as an important reconstructive option in the armamentarium of the plastic surgeon, while managing hand and wrist defects. PMID:28713704

Effectiveness of a smartphone application for improving healthy lifestyles, a randomized clinical trial (EVIDENT II): study protocol

PubMed Central

2014-01-01

Background New technologies could facilitate changes in lifestyle and improve public health. However, no large randomized, controlled studies providing scientific evidence of the benefits of their use have been made. The aims of this study are to develop and validate a smartphone application, and to evaluate the effect of adding this tool to a standardized intervention designed to improve adherence to the Mediterranean diet and to physical activity. An evaluation is also made of the effect of modifying habits upon vascular structure and function, and therefore on arterial aging. Methods/Design A randomized, double-blind, multicenter, parallel group clinical trial will be carried out. A total of 1215 subjects under 70 years of age from the EVIDENT trial will be included. Counseling common to both groups (control and intervention) will be provided on adaptation to the Mediterranean diet and on physical activity. The intervention group moreover will receive training on the use of a smartphone application designed to promote a healthy diet and increased physical activity, and will use the application for three months. The main study endpoints will be the changes in physical activity, assessed by accelerometer and the 7-day Physical Activity Recall (PAR) interview, and adaptation to the Mediterranean diet, as evaluated by an adherence questionnaire and a food frequency questionnaire (FFQ). Evaluation also will be made of vascular structure and function based on central arterial pressure, the radial augmentation index, pulse velocity, the cardio-ankle vascular index, and carotid intima-media thickness. Discussion Confirmation that the new technologies are useful for promoting healthier lifestyles and that their effects are beneficial in terms of arterial aging will have important clinical implications, and may contribute to generalize their application in favor of improved population health. Trial registration Clinical Trials.gov Identifier: NCT02016014 PMID:24628961

The influence of sub-grid scale motions on particle collision in homogeneous isotropic turbulence

NASA Astrophysics Data System (ADS)

Xiong, Yan; Li, Jing; Liu, Zhaohui; Zheng, Chuguang

2018-02-01

The absence of sub-grid scale (SGS) motions leads to severe errors in particle pair dynamics, which represents a great challenge to the large eddy simulation of particle-laden turbulent flow. In order to address this issue, data from direct numerical simulation (DNS) of homogenous isotropic turbulence coupled with Lagrangian particle tracking are used as a benchmark to evaluate the corresponding results of filtered DNS (FDNS). It is found that the filtering process in FDNS will lead to a non-monotonic variation of the particle collision statistics, including radial distribution function, radial relative velocity, and the collision kernel. The peak of radial distribution function shifts to the large-inertia region due to the lack of SGS motions, and the analysis of the local flowstructure characteristic variable at particle position indicates that the most effective interaction scale between particles and fluid eddies is increased in FDNS. Moreover, this scale shifting has an obvious effect on the odd-order moments of the probability density function of radial relative velocity, i.e. the skewness, which exhibits a strong correlation to the variance of radial distribution function in FDNS. As a whole, the radial distribution function, together with radial relative velocity, can compensate the SGS effects for the collision kernel in FDNS when the Stokes number based on the Kolmogorov time scale is greater than 3.0. However, it still leaves considerable errors for { St}_k <3.0.

Simulation of balloon angioplasty in residually stressed blood vessels-Application of a gradient-enhanced fibre damage model.

PubMed

Polindara, César; Waffenschmidt, Tobias; Menzel, Andreas

2016-08-16

In this contribution we study the balloon angioplasty in a residually stressed artery by means of a non-local gradient-enhanced fibre damage model. The balloon angioplasty is a common surgical intervention used to extend or reopen narrowed blood vessels in order to restore the continuous blood flow in, for instance, atherosclerotic arteries. Inelastic, i.e. predominantly damage-related and elastoplastic processes are induced in the artery during its inflation resulting in an irreversible deformation. As a beneficial consequence, provided that the inelastic deformations do not exceed a specific limit, higher deformations can be obtained within the same pressure level and a continuous blood flow can be guaranteed. In order to study the mechanical response of the artery in this scenario, we make use of the non-local gradient-enhanced model proposed in Waffenschmidt et al. (2014). In this contribution, we extend this model to make use of an incompressible format in connection with a Q1Q1P0 finite element implementation. The residual stresses in the artery are also taken into account following the framework presented in Waffenschmidt (2015). From the results it becomes apparent that, when the artery is subjected to radial stresses beyond the physiological range, damage evolution is triggered in the collagen fibres. The impact of the residual stresses on the structural response and on the circumferential stress distribution along the thickness of the arterial wall is also studied. It is observed that the residual stresses have a beneficial effect on the mechanical response of the arterial wall. Copyright © 2016 Elsevier Ltd. All rights reserved.

Systematic Review and Meta-analysis of Major Cardiovascular Outcomes for Radial Versus Femoral Access in Patients with Acute Coronary Syndrome

PubMed Central

Ruiz-Rodriguez, Ernesto; Asfour, Ahmed; Lolay, Georges; Ziada, Khaled M.; Abdel-Latif, Ahmed K.

2016-01-01

Objectives Radial artery access (RA) for left heart catheterization and percutaneous coronary interventions (PCIs) has been demonstrated to be safe and effective. Despite consistent data showing less bleeding complications compared with femoral artery access (FA), it continues to be underused in the United States, particularly in patients with acute coronary syndrome (ACS) in whom aggressive anticoagulation and platelet inhibition regimens are needed. This systematic review and meta-analysis aims to compare major cardiovascular outcomes and safety endpoints in patients with ACS managed with PCI using radial versus femoral access. Methods Randomized controlled trials and cohort studies comparing RA versus FA in patients with ACS were analyzed. Our primary outcomes were mortality, major adverse cardiac event, major bleeding, and access-related complications. A fixed-effects model was used for the primary analyses. Results Fifteen randomized controlled trials and 17 cohort studies involving 44,854 patients with ACS were identified. Compared with FA, RA was associated with a reduction in major bleeding (odds ratio [OR] 0.45, 95% confidence interval [CI] 0.33–0.61; P < 0.001), access-related complications (OR 0.27, 95% CI 0.18–0.39; P < 0.001), mortality (OR 0.64, 95% CI 0.54–0.75; P < 0.001), and major adverse cardiac event (OR 0.70, 95% CI 0.57–0.85; P < 0.001). These significant reductions were consistent across different study designs and clinical presentations. Conclusions Based on this large meta-analysis, RA for primary PCI in the setting of ACS is associated with reduction in cardiac and safety endpoints when compared with FA in both urgent and elective procedures. This should encourage a wider adoption of this technique among centers and interventional cardiologists. PMID:26741877

Effect of inorganic nitrate on exercise capacity in heart failure with preserved ejection fraction.

PubMed

Zamani, Payman; Rawat, Deepa; Shiva-Kumar, Prithvi; Geraci, Salvatore; Bhuva, Rushik; Konda, Prasad; Doulias, Paschalis-Thomas; Ischiropoulos, Harry; Townsend, Raymond R; Margulies, Kenneth B; Cappola, Thomas P; Poole, David C; Chirinos, Julio A

2015-01-27

Inorganic nitrate (NO3(-)), abundant in certain vegetables, is converted to nitrite by bacteria in the oral cavity. Nitrite can be converted to nitric oxide in the setting of hypoxia. We tested the hypothesis that NO3(-) supplementation improves exercise capacity in heart failure with preserved ejection fraction via specific adaptations to exercise. Seventeen subjects participated in this randomized, double-blind, crossover study comparing a single dose of NO3-rich beetroot juice (NO3(-), 12.9 mmol) with an identical nitrate-depleted placebo. Subjects performed supine-cycle maximal-effort cardiopulmonary exercise tests, with measurements of cardiac output and skeletal muscle oxygenation. We also assessed skeletal muscle oxidative function. Study end points included exercise efficiency (total work/total oxygen consumed), peak VO2, total work performed, vasodilatory reserve, forearm mitochondrial oxidative function, and augmentation index (a marker of arterial wave reflections, measured via radial arterial tonometry). Supplementation increased plasma nitric oxide metabolites (median, 326 versus 10 μmol/L; P=0.0003), peak VO2 (12.6±3.7 versus 11.6±3.1 mL O2·min(-1)·kg(-1); P=0.005), and total work performed (55.6±35.3 versus 49.2±28.9 kJ; P=0.04). However, efficiency was unchanged. NO3(-) led to greater reductions in systemic vascular resistance (-42.4±16.6% versus -31.8±20.3%; P=0.03) and increases in cardiac output (121.2±59.9% versus 88.7±53.3%; P=0.006) with exercise. NO3(-) reduced aortic augmentation index (132.2±16.7% versus 141.4±21.9%; P=0.03) and tended to improve mitochondrial oxidative function. NO3(-) increased exercise capacity in heart failure with preserved ejection fraction by targeting peripheral abnormalities. Efficiency did not change as a result of parallel increases in total work and VO2. NO3(-) increased exercise vasodilatory and cardiac output reserves. NO3(-) also reduced arterial wave reflections, which are linked to left ventricular diastolic dysfunction and remodeling. www.clinicaltrials.gov. Unique identifier: NCT01919177. © 2014 American Heart Association, Inc.

Decision-Assist and Closed-Loop Control of Fluid Therapy

DTIC Science & Technology

2012-03-30

achieve target endpoints while reducing fluid needs in experimental models of hemorrhage. During the previous funding cycle, along with our... IABP ) (standard of care blood pressure monitor "gold standard") in cardiac surgical patients to blood pressure recorded by the WVSM. Rational for...WVSM vs Gold standard IABP 2) History of neuropraxia 3) Refusal to consent 4) Failure to obtain radial artery cannulation Ten CPB Patients were

Reconstruction of cubital fossa skin necrosis with radial collateral artery perforator-based propeller flap (RCAP).

PubMed

Chaput, B; Gandolfi, S; Ho Quoc, C; Chavoin, J-P; Garrido, I; Grolleau, J-L

2014-02-01

In recent years, perforator flaps have become an indispensable tool for the reconstruction process. Most recently, "propeller" perforator flaps allow each perforator vessels to become a flap donor site. Once the perforator of interest is identified by acoustic Doppler, the cutaneous or fascio-cutaneous island is designed and then customized according to the principle of "perforasome". So, the flap can be rotated such a propeller, up to 180°. Ideally the donor site is self-closing, otherwise it can be grafted at the same time. Through a skin necrosis secondary to a contrast medium extravasation of the cubital fossa in a 47-year-old man, we describe the use of propeller perforator flap based on a perforator of the radial collateral artery (RCAP). The perforator was identified preoperatively by acoustic Doppler then the flap was adapted bespoke to cover the loss of substance. Ultimately, the result was very satisfying. Well experienced for lower-extremity reconstruction, perforator-based propeller flap are still few reported for upper limb. It is likely that in the future, propeller flap supersede in many indication not only free flaps and locoregional flaps but also, leaving no room for uncertainties of the vascular network, the classic random flaps. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

Heritability and intrafamilial aggregation of arterial characteristics.

PubMed

Seidlerová, Jitka; Bochud, Murielle; Staessen, Jan A; Cwynar, Marcin; Dolejsová, Milena; Kuznetsova, Tatiana; Nawrot, Tim; Olszanecka, Agnieszka; Stolarz, Katarzyna; Thijs, Lutgarde; Wojciechowska, Wiktoria; Struijker-Boudier, Harry A; Kawecka-Jaszcz, Kalina; Elston, Robert C; Fagard, Robert; Filipovský, Jan

2008-04-01

We investigated the heritability and familial aggregation of various indexes of arterial stiffness and wave reflection and we partitioned the phenotypic correlation between these traits into shared genetic and environmental components. Using a family-based population sample, we recruited 204 parents (mean age, 51.7 years) and 290 offspring (29.4 years) from the population in Cracow, Poland (62 families), Hechtel-Eksel, Belgium (36), and Pilsen, the Czech Republic (50). We measured peripheral pulse pressure (PPp) sphygmomanometrically at the brachial artery; central pulse pressure (PPc), the peripheral augmentation indexes (PAIxs) and central augmentation indexes (CAIxs) by applanation tonometry at the radial artery; and aortic pulse wave velocity (PWV) by tonometry or ultrasound. In multivariate-adjusted analyses, we used the ASSOC and PROC GENMOD procedures as implemented in SAGE and SAS, respectively. We found significant heritability for PAIx, CAIx, PPc and mean arterial pressure ranging from 0.37 to 0.41; P < or = 0.0001. The method of intrafamilial concordance confirmed these results; intrafamilial correlation coefficients were significant for all arterial indexes (r > or = 0.12; P < or = 0.02) with the exception of PPc (r = -0.007; P = 0.90) in parent-offspring pairs. The sib-sib correlations were also significant for CAIx (r = 0.22; P = 0.001). The genetic correlation between PWV and the other arterial indexes were significant (rhoG > or = 0.29; P < 0.0001). The corresponding environmental correlations were only significantly positive for PPp (rhoE = 0.10, P = 0.03). The observation of significant intrafamilial concordance and heritability of various indexes of arterial stiffness as well as the genetic correlations among arterial phenotypes strongly support the search for shared genetic determinants underlying these traits.

METABOLIC SYNDROME AND ARTERIAL ELASTICITY IN YOUTH

PubMed Central

Gardner, Andrew W.; Parker, Donald E.; Krishnan, Sowmya; Chalmers, Laura J.

2012-01-01

Objective To compare arterial elasticity in children, adolescents, and young adults with and without metabolic syndrome (MetS), and to assess which MetS components, demographic measures, and body composition measures are associated with arterial elasticity. Materials/Methods Two-hundred six subjects (107 females and 99 males) between the ages of 10 and 20 years were recruited by local newspaper advertisements, university email advertisements, and informational flyers. Subjects were assessed on MetS components, demographic measures, body composition measures, and arterial elasticity via radial tonometry. Forty-five subjects (22%) had MetS, as defined by the International Diabetes Federation, and 161 subjects (78%) did not. Results The primary novel finding was that group differences were not observed for large artery elasticity index (LAEI) (MetS = 16.1±4.4 (ml × mmHg−1) × 10 (mean±SD), control = 15.4±4.9, (ml × mmHg−1) × 10, p=0.349), and small artery elasticity index (SAEI) (MetS = 9.2±2.7 (ml × mmHg−1) × 100, control = 8.4±2.9, (ml × mmHg−1) × 100, p=0.063). In the MetS group, fat free mass was positively associated with arterial elasticity, and was the strongest multivariate predictor of LAEI (partial R2=0.41) and SAEI (partial R2=0.41). Conclusions Youth with MetS did not exhibit differences in LAEI and SAEI compared to controls. Furthermore, fat free mass of youth with MetS was positively associated with arterial elasticity, and was the strongest predictor of both LAEI and SAEI. The clinical implication is that exercise intervention designed to increase fat free mass might increase arterial elasticity in youth, particularly in youth with MetS. PMID:23142161

Free radial forearm adiposo-fascial flap for inferior maxillectomy defect reconstruction

PubMed Central

Thankappan, Krishnakumar; Trivedi, Nirav P.; Sharma, Mohit; Kuriakose, Moni A.; Iyer, Subramania

2009-01-01

A free radial forearm fascial flap has been described for intraoral reconstruction. Adiposo-fascial flap harvesting involves few technical modifications from the conventional radial forearm fascio-cutaneous free flap harvesting. We report a case of inferior maxillectomy defect reconstruction in a 42-year-old male with a free radial forearm adiposo-fascial flap with good aesthetic and functional outcome with minimal primary and donor site morbidity. The technique of raising the flap and closing the donor site needs to be meticulous in order to achieve good cosmetic and functional outcome. PMID:19881028

Retrieval of a subintimal fractured guide wire from the brachial artery following saphenous vein graft stenting.

PubMed

Danson, Edward J; Ward, Michael

2015-06-01

We present a case of a 58-year-old woman with diabetes mellitus with a history of angina, coronary artery bypass 24 years previously and who underwent retrieval of a fractured coronary buddy wire from the right brachial artery following attempted coronary intervention to a saphenous vein graft via the right radial route. Attempted removal of the guide wire had caused guide catheter-induced dissection of the vein graft in addition to a distal stent edge dissection before fracture in the brachial artery. The fractured end of the buddy wire was found to be in the subintimal space and could only be retrieved by advancing the wire into the subclavian artery by means of wrapping its free portion around the guiding catheter. Its fractured end could then be snared into the guiding catheter but could only be withdrawn from behind the stented segment in the vein graft by means of a trap balloon in the guiding catheter. Successful stenting of a guide catheter-induced dissection and distal stent edge dissection within the vein graft was then performed. This case highlights the hazards of deploying stents over buddy wires and of fractured guide wires in coronary intervention. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

[Anesthetic management for cerebral aneurysm surgery in a patient with aortitis syndrome accompanied by lung edema].

PubMed

Maeda, Ryoko; Kohno, Yumiko; Hoshino, Hajime; Suzuki, Hideo; Hirabayashi, Yoshiyuki; Seo, Norimasa

2003-08-01

A 48-year-old woman with aortitis syndrome underwent clipping of dissecting aneurysm of the left posterior inferior cerebellar artery following subarachnoid hemorrhage. Preoperative echocardiography demonstrated moderate aortic regurgitation and pulmonary hypertension. Intravenous infusion (1900 ml.day-1) was performed to avoid cerebral vasospasm, but the patient developed lung edema. She received delayed surgical treatment after the improvement of lung symptoms. Anesthesia was induced with fentanyl (0.1 mg), propofol (90 mg) and vecuronium (6 mg). Radial arterial flow was judged to be insufficient for cannulation, and a cannulation was therefore performed on the dorsal pedis artery. During induction of anesthesia, there was a significant decrease in the arterial pressure, that required a total of 32 mg of intravenous ephedrine. Following tracheal intubation, a central venous catheter was inserted and dopamine was continuously administered. The patient was positioned in the park bench position. We thought that the placement of the introducer for Swan-Ganz catheter was difficult under the position and Swan-Ganz catheter was not inserted. Anesthesia was maintained with sevoflurane, air, and oxygen. We continuously monitored the central venous pressure as an indicator of fluid balance. In this case, we monitored dorsal pedis arterial pressure directly, which might not be sufficiently reliable to predict the decrease in cerebral blood flow.

Impact of fluid-structure interaction on direct tumor-targeting in a representative hepatic artery system.

PubMed

Childress, Emily M; Kleinstreuer, Clement

2014-03-01

Direct targeting of solid tumors with chemotherapeutic drugs and/or radioactive microspheres can be a treatment option which minimizes side-effects and reduces cost. Briefly, computational analysis generates particle release maps (PRMs) which visually link upstream particle injection regions in the main artery with associated exit branches, some connected to tumors. The overall goal is to compute patient-specific PRMs realistically, accurately, and cost-effectively, which determines the suitable radial placement of a micro-catheter for optimal particle injection. Focusing in this paper on new steps towards realism and accuracy, the impact of fluid-structure interaction on direct drug-targeting is evaluated, using a representative hepatic artery system with liver tumor as a test bed. Specifically, the effect of arterial wall motion was demonstrated by modeling a two-way fluid-structure interaction analysis with Lagrangian particle tracking in the bifurcating arterial system. Clearly, rapid computational evaluation of optimal catheter location for tumor-targeting in a clinical application is very important. Hence, rigid-wall cases were also compared to the flexible scenario to establish whether PRMs generated when based on simplifying assumptions could provide adequate guidance towards ideal catheter placement. It was found that the best rigid (i.e., time-averaged) geometry is the physiological one that occurs during the diastolic targeting interval.

Carbon monoxide inhalation induces headache in a human headache model.

PubMed

Arngrim, Nanna; Schytz, Henrik Winther; Britze, Josefine; Vestergaard, Mark Bitsch; Sander, Mikael; Olsen, Karsten Skovgaard; Olesen, Jes; Ashina, Messoud

2018-04-01

Introduction Carbon monoxide (CO) is an endogenously produced signalling molecule that has a role in nociceptive processing and cerebral vasodilatation. We hypothesized that inhalation of CO would induce headache and vasodilation of cephalic and extracephalic arteries. Methods In a randomized, double-blind, placebo-controlled crossover design, 12 healthy volunteers were allocated to inhalation of CO (carboxyhemoglobin 22%) or placebo on two separate days. Headache was scored on a verbal rating scale from 0-10. We recorded mean blood velocity in the middle cerebral artery (VMCA) by transcranial Doppler, diameter of the superficial temporal artery (STA) and radial artery (RA) by high-resolution ultrasonography and facial skin blood flow by laser speckle contrast imaging. Results Ten volunteers developed headache after CO compared to six after placebo. The area under the curve for headache (0-12 hours) was increased after CO compared with placebo ( p = 0.021). CO increased VMCA ( p = 0.002) and facial skin blood flow ( p = 0.012), but did not change the diameter of the STA ( p = 0.060) and RA ( p = 0.433). Conclusion In conclusion, the study demonstrated that CO caused mild prolonged headache but no arterial dilatation in healthy volunteers. We suggest this may be caused by a combination of hypoxic and direct cellular effects of CO.

Satisfiability of logic programming based on radial basis function neural networks

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hamadneh, Nawaf; Sathasivam, Saratha; Tilahun, Surafel Luleseged

2014-07-10

In this paper, we propose a new technique to test the Satisfiability of propositional logic programming and quantified Boolean formula problem in radial basis function neural networks. For this purpose, we built radial basis function neural networks to represent the proportional logic which has exactly three variables in each clause. We used the Prey-predator algorithm to calculate the output weights of the neural networks, while the K-means clustering algorithm is used to determine the hidden parameters (the centers and the widths). Mean of the sum squared error function is used to measure the activity of the two algorithms. We appliedmore » the developed technique with the recurrent radial basis function neural networks to represent the quantified Boolean formulas. The new technique can be applied to solve many applications such as electronic circuits and NP-complete problems.« less

Reliability and concurrent validity of a peripheral pulse oximeter and health-app system for the quantification of heart rate in healthy adults.

PubMed

Losa-Iglesias, Marta Elena; Becerro-de-Bengoa-Vallejo, Ricardo; Becerro-de-Bengoa-Losa, Klark Ricardo

2016-06-01

There are downloadable applications (Apps) for cell phones that can measure heart rate in a simple and painless manner. The aim of this study was to assess the reliability of this type of App for a Smartphone using an Android system, compared to the radial pulse and a portable pulse oximeter. We performed a pilot observational study of diagnostic accuracy, randomized in 46 healthy volunteers. The patients' demographic data and cardiac pulse were collected. Radial pulse was measured by palpation of the radial artery with three fingers at the wrist over the radius; a low-cost portable, liquid crystal display finger pulse oximeter; and a Heart Rate Plus for Samsung Galaxy Note®. This study demonstrated high reliability and consistency between systems with respect to the heart rate parameter of healthy adults using three systems. For all parameters, ICC was > 0.93, indicating excellent reliability. Moreover, CVME values for all parameters were between 1.66-4.06 %. We found significant correlation coefficients and no systematic differences between radial pulse palpation and pulse oximeter and a high precision. Low-cost pulse oximeter and App systems can serve as valid instruments for the assessment of heart rate in healthy adults. © The Author(s) 2014.

Fabrication and Optimal Design of Biodegradable Polymeric Stents for Aneurysms Treatments

PubMed Central

Han, Xue; Wu, Xia; Kelly, Michael; Chen, Xiongbiao

2017-01-01

An aneurysm is a balloon-like bulge in the wall of blood vessels, occurring in major arteries of the heart and brain. Biodegradable polymeric stent-assisted coiling is expected to be the ideal treatment of wide-neck complex aneurysms. This paper presents the development of methods to fabricate and optimally design biodegradable polymeric stents for aneurysms treatment. Firstly, a dispensing-based rapid prototyping (DBRP) system was developed to fabricate coil and zigzag structures of biodegradable polymeric stents. Then, compression testing was carried out to characterize the radial deformation of the stents fabricated with the coil or zigzag structure. The results illustrated the stent with a zigzag structure has a stronger radial stiffness than the one with a coil structure. On this basis, the stent with a zigzag structure was chosen for the development of a finite element model for simulating the real compression tests. The result showed the finite element model of biodegradable polymeric stents is acceptable within a range of radial deformation around 20%. Furthermore, the optimization of the zigzag structure was performed with ANSYS DesignXplorer, and the results indicated that the total deformation could be decreased by 35.7% by optimizing the structure parameters, which would represent a significant advance of the radial stiffness of biodegradable polymeric stents. PMID:28264515

Radial nerve palsy in mid/distal humeral fractures: is early exploration effective?

PubMed

Keighley, Geffrey; Hermans, Deborah; Lawton, Vidya; Duckworth, David

2018-03-01

Radial nerve palsies are a common complication with displaced distal humeral fractures. This case series examines the outcomes of early operative exploration and decompression of the nerve with fracture fixation with the view that this provides a solid construct for optimisation of nerve recovery. A total of 10 consecutive patients with a displaced distal humeral fracture and an acute radial nerve palsy were treated by the senior author by open reduction and internal fixation of the distal humerus and exploration and decompression of the radial nerve. Motor function and sensation of the radial nerve was assessed in the post-operative period every 2 months or until full recovery of the radial nerve function had occurred. All patients (100%) had recovery of motor and sensation function of their upper limb in the radial nerve distribution over a 12-month period. Recovery times ranged between 4 and 32 weeks, with the median time to recovery occurring at 26 weeks and the average time to full recovery being 22.9 weeks. Wrist extension recovered by an average of 3 months (range 2-26 weeks) and then finger extension started to recover 2-6 weeks after this. Disability of the arm, shoulder and hand scores ranged from 0 to 11.8 at greater than 1 year post-operatively. Our study demonstrated that early operative exploration of the radial nerve when performing an open stabilization of displaced distal humeral fractures resulted in a 100% recovery of the radial nerve. © 2017 Royal Australasian College of Surgeons.

Conformable amplified lead zirconate titanate sensors with enhanced piezoelectric response for cutaneous pressure monitoring.

PubMed

Dagdeviren, Canan; Su, Yewang; Joe, Pauline; Yona, Raissa; Liu, Yuhao; Kim, Yun-Soung; Huang, YongAn; Damadoran, Anoop R; Xia, Jing; Martin, Lane W; Huang, Yonggang; Rogers, John A

2014-08-05

The ability to measure subtle changes in arterial pressure using devices mounted on the skin can be valuable for monitoring vital signs in emergency care, detecting the early onset of cardiovascular disease and continuously assessing health status. Conventional technologies are well suited for use in traditional clinical settings, but cannot be easily adapted for sustained use during daily activities. Here we introduce a conformal device that avoids these limitations. Ultrathin inorganic piezoelectric and semiconductor materials on elastomer substrates enable amplified, low hysteresis measurements of pressure on the skin, with high levels of sensitivity (~0.005 Pa) and fast response times (~0.1 ms). Experimental and theoretical studies reveal enhanced piezoelectric responses in lead zirconate titanate that follow from integration on soft supports as well as engineering behaviours of the associated devices. Calibrated measurements of pressure variations of blood flow in near-surface arteries demonstrate capabilities for measuring radial artery augmentation index and pulse pressure velocity.

A Linearized and Incompressible Constitutive Model for Arteries

PubMed Central

Liu, Y.; Zhang, W.; Wang, C.; Kassab, G. S.

2011-01-01

In many biomechanical studies, blood vessels can be modeled as pseudoelastic orthotropic materials that are incompressible (volume-preserving) under physiological loading. To use a minimum number of elastic constants to describe the constitutive behavior of arteries, we adopt a generalized Hooke’s law for the co-rotational Cauchy stress and a recently proposed logarithmic-exponential strain. This strain tensor absorbs the material nonlinearity and its trace is zero for volume-preserving deformations. Thus, the relationships between model parameters due to the incompressibility constraint are easy to analyze and interpret. In particular, the number of independent elastic constants reduces from ten to seven in the orthotropic model. As an illustratory study, we fit this model to measured data of porcine coronary arteries in inflation-stretch tests. Four parameters, n (material nonlinearity), Young’s moduli E1 (circumferential), E2 (axial), and E3 (radial) are necessary to fit the data. The advantages and limitations of this model are discussed. PMID:21605567

A linearized and incompressible constitutive model for arteries.

PubMed

Liu, Y; Zhang, W; Wang, C; Kassab, G S

2011-10-07

In many biomechanical studies, blood vessels can be modeled as pseudoelastic orthotropic materials that are incompressible (volume-preserving) under physiological loading. To use a minimum number of elastic constants to describe the constitutive behavior of arteries, we adopt a generalized Hooke's law for the co-rotational Cauchy stress and a recently proposed logarithmic-exponential strain. This strain tensor absorbs the material nonlinearity and its trace is zero for volume-preserving deformations. Thus, the relationships between model parameters due to the incompressibility constraint are easy to analyze and interpret. In particular, the number of independent elastic constants reduces from ten to seven in the orthotropic model. As an illustratory study, we fit this model to measured data of porcine coronary arteries in inflation-stretch tests. Four parameters, n (material nonlinearity), Young's moduli E₁ (circumferential), E₂ (axial), and E₃ (radial) are necessary to fit the data. The advantages and limitations of this model are discussed. Copyright © 2011 Elsevier Ltd. All rights reserved.

Meshless Solution of the Problem on the Static Behavior of Thin and Thick Laminated Composite Beams

NASA Astrophysics Data System (ADS)

Xiang, S.; Kang, G. W.

2018-03-01

For the first time, the static behavior of laminated composite beams is analyzed using the meshless collocation method based on a thin-plate-spline radial basis function. In the approximation of a partial differential equation by using a radial basis function, the shape parameter has an important role in ensuring the numerical accuracy. The choice of a shape parameter in the thin plate spline radial basis function is easier than in other radial basis functions. The governing differential equations are derived based on Reddy's third-order shear deformation theory. Numerical results are obtained for symmetric cross-ply laminated composite beams with simple-simple and cantilever boundary conditions under a uniform load. The results found are compared with available published ones and demonstrate the accuracy of the present method.

Sexual Function Is an Indicator of Central Arterial Stiffness and Arterial Stiffness Gradient in Japanese Adult Men.

PubMed

Kumagai, Hiroshi; Yoshikawa, Toru; Myoenzono, Kanae; Kosaki, Keisei; Akazawa, Nobuhiko; Asako, Zempo-Miyaki; Tsujimoto, Takehiko; Kidokoro, Tetsuhiro; Tanaka, Kiyoji; Maeda, Seiji

2018-05-05

As arterial stiffness increases in the absence of subjective symptoms, a personal indicator that reflects increased risk of cardiovascular disease is necessary. Penile erection is regulated by vascular function, and atherosclerosis affects the penile artery earlier than it affects the coronary and carotid arteries. Therefore, we hypothesized that deterioration of erectile function could be a marker of increased risk for cardiovascular disease. To test our hypothesis, we assessed erectile function and arterial stiffness in a cross-sectional study. Carotid-femoral pulse wave velocity (PWV), brachial-ankle PWV, femoral-ankle PWV, and arterial stiffness gradient (PWV ratio: carotid-femoral PWV/femoral-ankle PWV) were measured as indexes of central, systemic, and peripheral arterial stiffness and peripheral organ damage, respectively, in 317 adult men. In addition, erectile function was assessed by using the questionnaire International Index of Erectile Function 5 (a descending score indicates worsening of erectile function). The scores of male sexual function were inversely correlated with carotid-femoral PWV ( r s =-0.41), brachial-ankle PWV ( r s =-0.35), femoral-ankle PWV ( r s =-0.19), and PWV ratio ( r s =-0.33). Furthermore, multivariate linear regression analyses revealed that International Index of Erectile Function 5 scores were significantly associated with carotid-femoral PWV (β=-0.22) and PWV ratio (β=-0.25), but not with brachial-ankle PWV and femoral-ankle PWV. Our results indicated that erectile function is independently associated with central arterial stiffness and peripheral organ damage. These findings suggest that male sexual function could be an easily identifiable and independent marker of increased central arterial stiffness and peripheral organ damage. © 2018 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

Middle-aged, but not young, rats develop cognitive impairment and cortical neurodegeneration following the four-vessel occlusion/internal carotid artery model of chronic cerebral hypoperfusion.

PubMed

Ferreira, Emilene D Fiuza; Romanini, Cássia V; Mori, Marco A; de Oliveira, Rúbia M Weffort; Milani, Humberto

2011-10-01

Permanent, stepwise occlusion of the vertebral arteries (VAs) and internal carotid arteries (ICAs) following the sequence VA→ICA→ICA, with an interstage interval (ISI, →) of 7 days, has been investigated as a four-vessel occlusion (4-VO)/ICA model of chronic cerebral hypoperfusion. This model has the advantage of not causing retinal damage. In young rats, however, 4-VO/ICA with an ISI of 7 days fails to cause behavioral sequelae. We hypothesized that such a long ISI would allow the brain to efficiently compensate for cerebral hypoperfusion, preventing the occurrence of cognitive impairment and neurodegeneration. The present study evaluated whether brain neurodegeneration and learning/memory deficits can be expressed by reducing the length of the ISI and whether aging influences the outcome. Young, male Wistar rats were subjected to 4-VO/ICA with different ISIs (5, 4, 3 or 2 days). An ISI of 4 days was used in middle-aged rats. Ninety days after 4-VO/ICA, the rats were tested for learning/memory impairment in a modified radial maze and then examined for neurodegeneration of the hippocampus and cerebral cortex. Regardless of the ISI, young rats were not cognitively impaired, although hippocampal damage was evident. Learning/memory deficits and hippocampal and cortical neurodegeneration occurred in middle-aged rats. The data indicate that 4-VO/ICA has no impact on the capacity of young rats to learn the radial maze task, despite 51% hippocampal cell death. Such resistance is lost in middle-aged animals, for which the most extensive neurodegeneration observed in both the hippocampus and cerebral cortex may be responsible. © 2011 The Authors. European Journal of Neuroscience © 2011 Federation of European Neuroscience Societies and Blackwell Publishing Ltd.

Early results of percutaneous arteriovenous fistula creation with the Ellipsys Vascular Access System.

PubMed

Mallios, Alexandros; Jennings, William C; Boura, Benoit; Costanzo, Alessandro; Bourquelot, Pierre; Combes, Myriam

2018-04-18

We reviewed our initial experience creating a percutaneous arteriovenous fistula (pAVF) using a thermal resistance anastomosis device with proximal radial artery inflow. A retrospective review was conducted of all patients who underwent a pAVF creation procedure between May 2017 and October 2017. Primary end points of the study were technical success, patency by Doppler ultrasound examination or angiography, flow levels achieved, time to first use, and pAVF-related complications. A pAVF was attempted in 34 patients with technical success in 33 individuals (97%). Patency of the pAVF was 94%. Mean access flow was 946 mL/min (brachial artery measurement) at the latest follow-up visit (53-229 days; average, 141 days). At 6 weeks, all fistulas have been used or were ready for dialysis by clinical examination or ultrasound examination. Only one patient required superficialization of the upper arm cephalic vein by lipectomy. There were no adverse events related to the pAVF creation or use, nor was there need for further interventions. Successful pAVFs with proximal radial artery inflow were created with excellent initial results regarding technical success, patency, and safety. Advantages include avoidance of a surgical incision, short procedure times, good acceptance by patients, prompt access maturation, moderate flow, and low-pressure access, with possible reduction of risk for ischemic complications. Avoidance of vessel manipulation and side branch ligation might reduce risk of thrombosis and improve long-term patency and reduce need for further interventions. These early findings need to be confirmed in larger and longer follow-up studies. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

Intrauterine growth restriction decreases pulmonary alveolar and vessel growth and causes pulmonary artery endothelial cell dysfunction in vitro in fetal sheep

PubMed Central

Seedorf, Gregory J.; Brown, Alicia; Roe, Gates; O'Meara, Meghan C.; Gien, Jason; Tang, Jen-Ruey; Abman, Steven H.

2011-01-01

Intrauterine growth restriction (IUGR) increases the risk for bronchopulmonary dysplasia (BPD). Abnormal lung structure has been noted in animal models of IUGR, but whether IUGR adversely impacts fetal pulmonary vascular development and pulmonary artery endothelial cell (PAEC) function is unknown. We hypothesized that IUGR would decrease fetal pulmonary alveolarization, vascular growth, and in vitro PAEC function. Studies were performed in an established model of severe placental insufficiency and IUGR induced by exposing pregnant sheep to elevated temperatures. Alveolarization, quantified by radial alveolar counts, was decreased 20% (P < 0.005) in IUGR fetuses. Pulmonary vessel density was decreased 44% (P < 0.01) in IUGR fetuses. In vitro, insulin increased control PAEC migration, tube formation, and nitric oxide (NO) production. This response was absent in IUGR PAECs. VEGFA stimulated tube formation, and NO production also was absent. In control PAECs, insulin increased cell growth by 68% (P < 0.0001). Cell growth was reduced in IUGR PAECs by 29% at baseline (P < 0.01), and the response to insulin was attenuated (P < 0.005). Despite increased basal and insulin-stimulated Akt phosphorylation in IUGR PAECs, endothelial NO synthase (eNOS) protein expression as well as basal and insulin-stimulated eNOS phosphorylation were decreased in IUGR PAECs. Both VEGFA and VEGFR2 also were decreased in IUGR PAECs. We conclude that fetuses with IUGR are characterized by decreased alveolar and vascular growth and PAEC dysfunction in vitro. This may contribute to the increased risk for adverse respiratory outcomes and BPD in infants with IUGR. PMID:21873446

Endothelial dysfunction in patients with chronic heart failure is independently associated with increased incidence of hospitalization, cardiac transplantation, or death.

PubMed

Fischer, D; Rossa, S; Landmesser, U; Spiekermann, S; Engberding, N; Hornig, B; Drexler, H

2005-01-01

Endothelial dysfunction of coronary and peripheral arteries has been demonstrated in patients with chronic heart failure (CHF) and appears to be associated with functional implications. However, it is unknown whether endothelial dysfunction in CHF is independently associated with impaired outcome or progression of the disease. We assessed the follow-up of 67 consecutive patients with CHF [New York Heart Association (NYHA) functional class II-III] in which flow-dependent, endothelium-mediated vasodilation (FDD) of the radial artery was assessed by high resolution ultrasound. The primary endpoint was defined by cardiac death, hospitalization due to worsening of heart failure (NYHA class IV, pulmonary oedema), or heart transplantation. Cox regression analysis was used to determine whether FDD was associated with these heart failure-related events. During a median follow-up of 45.7 months 24 patients had an event: 18 patients were hospitalized due to worsening of heart failure or heart transplantation, six patients died for cardiac reasons. Cox regression analysis demonstrated that FDD (P<0.01), diabetes mellitus (P<0.01), and ejection fraction (P<0.01) were independent predictive factors for the occurrence of the primary endpoint. The Kaplan-Meier survival curve revealed a significantly better clinical outcome in patients with FDD above the median (6.2%) compared with those with FDD below the median (P<0.013). These observations suggest that endothelium-mediated vasodilation represents an independent predictor of cardiac death and hospitalization in patients with CHF, consistent with the notion that endothelium-derived nitric oxide may play a protective role in heart failure.

Improved accuracy of methemoglobin detection by pulse CO-oximetry during hypoxia.

PubMed

Feiner, John R; Bickler, Philip E

2010-11-01

Methemoglobin in the blood cannot be detected by conventional pulse oximetry and may bias the oximeter's estimate (Spo(2)) of the true arterial functional oxygen saturation (Sao(2)). A recently introduced "pulse CO-oximeter" (Masimo Rainbow SET® Radical-7) that measures SpMet, a noninvasive measurement of the percentage of methemoglobin in arterial blood (%MetHb), was shown to read spuriously high values during hypoxia. In this study we sought to determine whether the manufacturer's modifications have improved the device's ability to detect and accurately measure methemoglobin and deoxyhemoglobin simultaneously. Twelve healthy adult volunteer subjects were fitted with sensors on the middle finger of each hand, and a radial arterial catheter was placed for blood sampling. Intravenous administration of ∼300 mg of sodium nitrite elevated subjects' methemoglobin levels to a 7% to 11% target level, and hypoxia was induced to different levels of Sao(2) (70% to 100%) by varying fractional inspired oxygen. Pulse CO-oximeter readings were compared with arterial blood values measured with a Radiometer ABL800 FLEX multi-wavelength oximeter. Pulse CO-oximeter methemoglobin reading performance was analyzed by the bias (SpMet-%MetHb), and by observing the incidence of meaningful reading errors and predictive value at the various hypoxia levels. Spo(2) bias (Spo(2)--Sao(2)), precision, and root-mean-square error were evaluated during conditions of elevated methemoglobin. Observations spanned 74% to 100% Sao(2) and 0.4% to 14.4% methemoglobin with 307 blood draws and 602 values from the 2 oximeters. Masimo methemoglobin reading bias and precision over the full Sao(2) span was 0.16% and 0.83%, respectively, and was similar across the span. Masimo Spo(2) readings were biased -1.93% across the 70% to 100% Sao(2) range. The Rainbow's methemoglobin readings are acceptably accurate over an oxygen saturation range of 74%-100% and a methemoglobin range of 0%-14%.

Dll4-Notch signaling determines the formation of native arterial collateral networks and arterial function in mouse ischemia models.

PubMed

Cristofaro, Brunella; Shi, Yu; Faria, Marcella; Suchting, Steven; Leroyer, Aurelie S; Trindade, Alexandre; Duarte, Antonio; Zovein, Ann C; Iruela-Arispe, M Luisa; Nih, Lina R; Kubis, Nathalie; Henrion, Daniel; Loufrani, Laurent; Todiras, Mihail; Schleifenbaum, Johanna; Gollasch, Maik; Zhuang, Zhen W; Simons, Michael; Eichmann, Anne; le Noble, Ferdinand

2013-04-01

Arteriogenesis requires growth of pre-existing arteriolar collateral networks and determines clinical outcome in arterial occlusive diseases. Factors responsible for the development of arteriolar collateral networks are poorly understood. The Notch ligand Delta-like 4 (Dll4) promotes arterial differentiation and restricts vessel branching. We hypothesized that Dll4 may act as a genetic determinant of collateral arterial networks and functional recovery in stroke and hind limb ischemia models in mice. Genetic loss- and gain-of-function approaches in mice showed that Dll4-Notch signaling restricts pial collateral artery formation by modulating arterial branching morphogenesis during embryogenesis. Adult Dll4(+/-) mice showed increased pial collateral numbers, but stroke volume upon middle cerebral artery occlusion was not reduced compared with wild-type littermates. Likewise, Dll4(+/-) mice showed reduced blood flow conductance after femoral artery occlusion, and, despite markedly increased angiogenesis, tissue ischemia was more severe. In peripheral arteries, loss of Dll4 adversely affected excitation-contraction coupling in arterial smooth muscle in response to vasopressor agents and arterial vessel wall adaption in response to increases in blood flow, collectively contributing to reduced flow reserve. We conclude that Dll4-Notch signaling modulates native collateral formation by acting on vascular branching morphogenesis during embryogenesis. Dll4 furthermore affects tissue perfusion by acting on arterial function and structure. Loss of Dll4 stimulates collateral formation and angiogenesis, but in the context of ischemic diseases such beneficial effects are overruled by adverse functional changes, demonstrating that ischemic recovery is not solely determined by collateral number but rather by vessel functionality.

Dll4-Notch signaling determines the formation of native arterial collateral networks and arterial function in mouse ischemia models

PubMed Central

Cristofaro, Brunella; Shi, Yu; Faria, Marcella; Suchting, Steven; Leroyer, Aurelie S.; Trindade, Alexandre; Duarte, Antonio; Zovein, Ann C.; Iruela-Arispe, M. Luisa; Nih, Lina R.; Kubis, Nathalie; Henrion, Daniel; Loufrani, Laurent; Todiras, Mihail; Schleifenbaum, Johanna; Gollasch, Maik; Zhuang, Zhen W.; Simons, Michael; Eichmann, Anne; le Noble, Ferdinand

2013-01-01

Arteriogenesis requires growth of pre-existing arteriolar collateral networks and determines clinical outcome in arterial occlusive diseases. Factors responsible for the development of arteriolar collateral networks are poorly understood. The Notch ligand Delta-like 4 (Dll4) promotes arterial differentiation and restricts vessel branching. We hypothesized that Dll4 may act as a genetic determinant of collateral arterial networks and functional recovery in stroke and hind limb ischemia models in mice. Genetic loss- and gain-of-function approaches in mice showed that Dll4-Notch signaling restricts pial collateral artery formation by modulating arterial branching morphogenesis during embryogenesis. Adult Dll4+/- mice showed increased pial collateral numbers, but stroke volume upon middle cerebral artery occlusion was not reduced compared with wild-type littermates. Likewise, Dll4+/- mice showed reduced blood flow conductance after femoral artery occlusion, and, despite markedly increased angiogenesis, tissue ischemia was more severe. In peripheral arteries, loss of Dll4 adversely affected excitation-contraction coupling in arterial smooth muscle in response to vasopressor agents and arterial vessel wall adaption in response to increases in blood flow, collectively contributing to reduced flow reserve. We conclude that Dll4-Notch signaling modulates native collateral formation by acting on vascular branching morphogenesis during embryogenesis. Dll4 furthermore affects tissue perfusion by acting on arterial function and structure. Loss of Dll4 stimulates collateral formation and angiogenesis, but in the context of ischemic diseases such beneficial effects are overruled by adverse functional changes, demonstrating that ischemic recovery is not solely determined by collateral number but rather by vessel functionality. PMID:23533173

Comparison of radial 4D Flow-MRI with perivascular ultrasound to quantify blood flow in the abdomen and introduction of a porcine model of pre-hepatic portal hypertension.

PubMed

Frydrychowicz, A; Roldan-Alzate, A; Winslow, E; Consigny, D; Campo, C A; Motosugi, U; Johnson, K M; Wieben, O; Reeder, S B

2017-12-01

Objectives of this study were to compare radial time-resolved phase contrast magnetic resonance imaging (4D Flow-MRI) with perivascular ultrasound (pvUS) and to explore a porcine model of acute pre-hepatic portal hypertension (PHTN). Abdominal 4D Flow-MRI and pvUS in portal and splenic vein, hepatic and both renal arteries were performed in 13 pigs of approximately 60 kg. In six pigs, measurements were repeated after partial portal vein (PV) ligature. Inter- and intra-reader comparisons and statistical analysis including Bland-Altman (BA) comparison, paired Student's t tests and linear regression were performed. PvUS and 4D Flow-MRI measurements agreed well; flow before partial PV ligature was 322 ± 30 ml/min in pvUS and 297 ± 27 ml/min in MRI (p = 0.294), and average BA difference was 25 ml/min [-322; 372]. Inter- and intra-reader results differed very little, revealed excellent correlation (R 2  = 0.98 and 0.99, respectively) and resulted in BA differences of -5 ml/min [-161; 150] and -2 ml/min [-28; 25], respectively. After PV ligature, PV flow decreased from 356 ± 50 to 298 ± 61 ml/min (p = 0.02), and hepatic arterial flow increased from 277 ± 36 to 331 ± 65 ml/min (p = n.s.). The successful in vivo comparison of radial 4D Flow-MRI to perivascular ultrasound revealed good agreement of abdominal blood flow although with considerable spread of results. A model of pre-hepatic PHTN was successfully introduced and acute responses monitored. • Radial 4D Flow-MRI in the abdomen was successfully compared to perivascular ultrasound. • Inter- and intra-reader testing demonstrated excellent reproducibility of upper abdominal 4D Flow-MRI. • A porcine model of acute pre-hepatic portal hypertension was successfully introduced. • 4D Flow-MRI successfully monitored acute changes in a model of portal hypertension.

Effects of high flavanol dark chocolate on cardiovascular function and platelet aggregation.

PubMed

Rull, Gurvinder; Mohd-Zain, Zetty N; Shiel, Julian; Lundberg, Martina H; Collier, David J; Johnston, Atholl; Warner, Timothy D; Corder, Roger

2015-08-01

Regular consumption of chocolate and cocoa products has been linked to reduced cardiovascular mortality. This study compared the effects of high flavanol dark chocolate (HFDC; 1064mg flavanols/day for 6weeks) and low flavanol dark chocolate (LFDC; 88mg flavanols/day for 6weeks) on blood pressure, heart rate, vascular function and platelet aggregation in men with pre-hypertension or mild hypertension. Vascular function was assessed by pulse wave analysis using radial artery applanation tonometry in combination with inhaled salbutamol (0.4mg) to assess changes due to endothelium-dependent vasodilatation. HFDC did not significantly reduce blood pressure compared to baseline or LFDC. Heart rate was increased by LFDC compared to baseline, but not by HFDC. Vascular responses to salbutamol tended to be greater after HFDC. Platelet aggregation induced by collagen or the thromboxane analogue U46619 was unchanged after LFDC or HFDC, whereas both chocolates reduced responses to ADP and the thrombin receptor activator peptide, SFLLRNamide (TRAP6), relative to baseline. Pre-incubation of platelets with theobromine also attenuated platelet aggregation induced by ADP or TRAP6. We conclude that consumption of HFDC confers modest improvements in cardiovascular function. Platelet aggregation is modulated by a flavanol-independent mechanism that is likely due to theobromine. Copyright © 2015 Elsevier Inc. All rights reserved.

Arterial function parameters in patients with metabolic syndrome and severe hypertriglyceridemia.

PubMed

Rinkūnienė, Egidija; Butkutė, Eglė; Puronaitė, Roma; Petrulionienė, Žaneta; Dženkevičiūtė, Vilma; Kasiulevičius, Vytautas; Laucevičius, Aleksandras

Hypertriglyceridemia (hTG) is 1 of the dyslipidemia manifestations in patients with metabolic syndrome (MetS). However, for several decades, the role of hTG in cardiovascular risk was not well established. The aim of this study was to assess the parameters of the vascular structure and function in patients with MetS and different degree of hTG. Patients (aged 40-65 years) with MetS were divided into 3 groups by triglyceride (TG) levels according to National Cholesterol Education Program Adult Treatment Panel III Guidelines: severe hTG (TG ≥ 500 mg/dL), moderate hTG (TG 200-499 mg/dL), and a control (TG < 150 mg/dL) groups. Noninvasive assessment of vascular parameters (aortic augmentation index adjusted for heart rate 75 bpm [AixHR75], pulse wave velocity [PWV], flow-mediated dilatation, and common carotid artery intima-media thickness (IMT)) were performed. Among the 1938 patients analyzed, 1041 had hTG. Moderate hTG was observed in 90.40% (n = 941), whereas severe TG was observed in 9.6% (n = 100) of patients. Overall TG concentration was 231.17 ± 184.23 mg/dL; in severe hTG group, TG concentration was 795.36 ± 368.45 mg/dL, in moderate hTG group 285.20 ± 70.86 mg/dL, and 112.48 ± 24.80 mg/dL in control group. AIxHR75 and IMT were the lowest in the severe hTG group (P < .001 for both). Mean arterial pressure, carotid-radial PWV (9.25 ± 1.13 vs 9.24 ± 1.28 vs 8.91 ± 1.28; P < .001) as well as carotid-femoral PWV (8.63 ± 1.65 vs 8.75 ± 1.58 vs 8.51 ± 1.6; P = .006) were the higher in hTG groups compared with control. There were no significant differences between groups in flow-mediated dilatation (3.39 ± 2.01 vs 3.26 ± 2.43 vs 3.45 ± 2.61, P = .283). Patients with MetS and severe hTG have lower IMT and AIxHR75 and higher PWV and mean arterial pressure. Many factors could affect arterial parameters, and more research are needed to investigate arterial parameters and hTG connection. Copyright © 2017 National Lipid Association. Published by Elsevier Inc. All rights reserved.

Green's function of radial inhomogeneous spheres excited by internal sources.

PubMed

Zouros, Grigorios P; Kokkorakis, Gerassimos C

2011-01-01

Green's function in the interior of penetrable bodies with inhomogeneous compressibility by sources placed inside them is evaluated through a Schwinger-Lippmann volume integral equation. In the case of a radial inhomogeneous sphere, the radial part of the unknown Green's function can be expanded in a double Dini's series, which allows analytical evaluation of the involved cumbersome integrals. The simple case treated here can be extended to more difficult situations involving inhomogeneous density as well as to the corresponding electromagnetic or elastic problem. Finally, numerical results are given for various inhomogeneous compressibility distributions.

Type 2 diabetes is associated with increased pulse wave velocity measured at different sites of the arterial system but not augmentation index in a Chinese population.

PubMed

Zhang, Minghua; Bai, Yongyi; Ye, Ping; Luo, Leiming; Xiao, Wenkai; Wu, Hongmei; Liu, Dejun

2011-10-01

Patients with type 2 diabetes have increased stiffness of central elastic arteries. However, whether peripheral muscular artery stiffness is equally affected by the disease remains sparsely examined. Moreover, the association between pulse wave velocity (PWV) and augmentation index (AIx) in diabetes is poorly understood. Type 2 diabetes is associated with the alterations in arterial stiffness (PWV and AIx) in a community-based population. A total of 79 Chinese patients with type 2 diabetes and 79 sex-, age- (±3 years), and body mass index- (±2 kg/m(2) ) matched healthy controls were studied. Carotid-femoral pulse wave velocity (CF-PWV), carotid-radial pulse wave velocity (CR-PWV), and carotid-ankle pulse wave velocity (CA-PWV) were calculated from tonometry waveforms and body surface measurements, whereas AIx was assessed using pulse wave analyses. In univariate analysis, patients with type 2 diabetes showed increased CF-PWV (P < 0.001), CR-PWV (P = 0.012), and CA-PWV (P = 0.016), and lower AIx (P = 0.017) than the control group. In multiple linear regression models adjusting for covariates, type 2 diabetes remained a significant determinant of CF-PWV. Fasting glucose was associated with CR-PWV but was not related to CA-PWV or AIx. Our findings suggest that patients with type 2 diabetes have increased central and peripheral artery stiffness, but preserved AIx compared to controls. Diabetes was a predictor of central artery stiffness, and glucose was a determinant of peripheral artery stiffness. © 2011 Wiley Periodicals, Inc.

Nasolabial facial artery and vein as recipient vessels for midface microsurgical reconstruction.

PubMed

Oh, Suk Joon; Jeon, Man Kyung; Koh, Sung Hoon

2011-05-01

Although free flap transfer is commonly performed to reconstruct facial defects, the submandibular facial artery and vein have historically been considered as adequate recipient vessels for microsurgical reconstruction. If the vascular pedicles of the free flap are short, vein grafts are necessary. The purpose of this study was to determine the indications for and effectiveness of using the nasolabial facial vessels for midfacial reconstruction. A retrospective chart review of 6 patients undergoing microsurgical reconstruction for defects of the face revealed 6 free tissue transfers in which the nasolabial facial artery and vein were considered for use as recipient vessels. Flap success rates were evaluated. Six patients (5 men and 1 woman) underwent 6 free flap transfers. Five anterior helix free flaps were used for the reconstruction of defects in the lower third of the nose. Nasal defects were due to trauma in 4 patients and squamous cell carcinoma in 1 patient. In 1 neurofibromatosis type 1 case, a radial forearm flap was used for reconstruction of the left orbital defect. The facial artery and vein in the nasolabial fold were used as the recipient artery and vein in every case. The mean length of follow-up was 5.8 years. All flaps survived. All patients were satisfied with the degree of aesthetic improvement after surgery.Use of the facial artery and vein in the nasolabial fold for facial reconstruction is reliable and safe. The nasolabial facial artery and vein should be considered as primary recipient vessels in microsurgical reconstruction of the midface.

Respiratory Motion-Resolved Compressed Sensing Reconstruction of Free-Breathing Radial Acquisition for Dynamic Liver Magnetic Resonance Imaging.

PubMed

Chandarana, Hersh; Feng, Li; Ream, Justin; Wang, Annie; Babb, James S; Block, Kai Tobias; Sodickson, Daniel K; Otazo, Ricardo

2015-11-01

This study aimed to demonstrate feasibility of free-breathing radial acquisition with respiratory motion-resolved compressed sensing reconstruction [extra-dimensional golden-angle radial sparse parallel imaging (XD-GRASP)] for multiphase dynamic gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced liver imaging, and to compare image quality to compressed sensing reconstruction with respiratory motion-averaging (GRASP) and prior conventional breath-held Cartesian-sampled data sets [BH volume interpolated breath-hold examination (VIBE)] in same patients. In this Health Insurance Portability and Accountability Act-compliant prospective study, 16 subjects underwent free-breathing continuous radial acquisition during Gd-EOB-DTPA injection and had prior BH-VIBE available. Acquired data were reconstructed using motion-averaging GRASP approach in which consecutive 84 spokes were grouped in each contrast-enhanced phase for a temporal resolution of approximately 14 seconds. Additionally, respiratory motion-resolved reconstruction was performed from the same k-space data by sorting each contrast-enhanced phase into multiple respiratory motion states using compressed sensing algorithm named XD-GRASP, which exploits sparsity along both the contrast-enhancement and respiratory-state dimensions.Contrast-enhanced dynamic multiphase XD-GRASP, GRASP, and BH-VIBE images were anonymized, pooled together in a random order, and presented to 2 board-certified radiologists for independent evaluation of image quality, with higher score indicating more optimal examination. The XD-GRASP reconstructions had significantly (all P < 0.05) higher overall image quality scores compared to GRASP for early arterial (reader 1: 4.3 ± 0.6 vs 3.31 ± 0.6; reader 2: 3.81 ± 0.8 vs 3.38 ± 0.9) and late arterial (reader 1: 4.5 ± 0.6 vs 3.63 ± 0.6; reader 2: 3.56 ± 0.5 vs 2.88 ± 0.7) phases of enhancement for both readers. The XD-GRASP also had higher overall image quality score in portal venous phase, which was significant for reader 1 (4.44 ± 0.5 vs 3.75 ± 0.8; P = 0.002). In addition, the XD-GRASP had higher overall image quality score compared to BH-VIBE for early (reader 1: 4.3 ± 0.6 vs 3.88 ± 0.6; reader 2: 3.81 ± 0.8 vs 3.50 ± 1.0) and late (reader 1: 4.5 ± 0.6 vs 3.44 ± 0.6; reader 2: 3.56 ± 0.5 vs 2.94 ± 0.9) arterial phases. Free-breathing motion-resolved XD-GRASP reconstructions provide diagnostic high-quality multiphase images in patients undergoing Gd-EOB-DTPA-enhanced liver examination.

Development of the arterial pattern in the upper limb of staged human embryos: normal development and anatomic variations

PubMed Central

RODRÍGUEZ-NIEDENFÜHR, M.; BURTON, G. J.; DEU, J.; SAÑUDO, J. R.

2001-01-01

A total of 112 human embryos (224 upper limbs) between stages 12 and 23 of development were examined. It was observed that formation of the arterial system in the upper limb takes place as a dual process. An initial capillary plexus appears from the dorsal aorta during stage 12 and develops at the same rate as the limb. At stage 13, the capillary plexus begins a maturation process involving the enlargement and differentiation of selected parts. This remodelling process starts in the aorta and continues in a proximal to distal sequence. By stage 15 the differentiation has reached the subclavian and axillary arteries, by stage 17 it has reached the brachial artery as far as the elbow, by stage 18 it has reached the forearm arteries except for the distal part of the radial, and finally by stage 21 the whole arterial pattern is present in its definitive morphology. This differentiation process parallels the development of the skeletal system chronologically. A number of arterial variations were observed, and classified as follows: superficial brachial (7.7%), accessory brachial (0.6%), brachioradial (14%), superficial brachioulnar (4.7%), superficial brachioulnoradial (0.7%), palmar pattern of the median (18.7%) and superficial brachiomedian (0.7%) arteries. They were observed in embryos belonging to stages 17–23 and were not related to a specific stage of development. Statistical comparison with the rates of variations reported in adults did not show significant differences. It is suggested that the variations arise through the persistence, enlargement and differentiation of parts of the initial network which would normally remain as capillaries or even regress. PMID:11693301

Contemporary Results of Surgical Management of Peripheral Mycotic Aneurysms.

PubMed

Salzler, Gg; Long, B; Avgerinos, Ed; Chaer, Ra; Leers, S; Hager, E; Makaroun, Ms; Eslami, Mh

2018-06-07

Mycotic aneurysms of the extremities occur infrequently but can cause severe life and limb complications. Traditional treatment typically includes debridement and revascularization, though in select patients ligation may be well tolerated. We reviewed our experience with these aneurysms treated with these two modalities. A retrospective review of patients treated for peripheral mycotic aneurysms at one institution from January 2005 to December 2015 was performed under an Institutional Review Board-approved protocol. Demographics, perioperative details, and long-term outcomes were collected and standard statistical methods were used to compare treatments. We identified 28 patients with 29 peripheral mycotic aneurysms. The majority of patients (19: 67.9%) were male with an average age of 60.1 ± 17 years. Among cases with a known cause, direct injury to artery was the most common precursor to mycotic aneurysm formation; iatrogenic causes were the most common (15: 51.7%) followed by intravenous drug use (5: 17.2%). Distal bacterial translocation was the other cause of mycotic aneurysm formation due to osteomyelitis (2:10.5%) and bacterial endocarditis (1:3.5%). The causes of the remainder of cases (6:20.7%) were unknown. Symptoms included fever (46.4%), drainage (42.9%), rupture (35.7%), erythema (21.4%), and limb ischemia (17.9%). Staphylococcus aureus was the most common bacteria isolated (38.5%, from 7 positive blood cultures and 3 positive wound culture) with 30% of these being MRSA, followed by Streptococcus species (11.5%), and other Staphylococcus (7.7%). Eight (30.7%) patients had negative cultures. The most common location of arterial aneurysm was the common femoral artery (17:58.6%), with 17.2% (5) occurring in the popliteal artery, 13.8% (4) in the brachial artery, 10.3% (3) in the radial or ulnar artery, and 3.5%(1) in the external iliac artery. 18 patients underwent revascularization, while 11 had resection/ligation without revascularization (4 femoral, 2 popliteal, 3 radial/ulnar, 1 brachial, and 1 external iliac). There was no significant difference in limb threatening ischemia between these two groups (p=0.14). Of those who were not revascularized, one developed significant initial ischemia but died prior to amputation and the other underwent revascularization within one year after tolerating the initial ligation. Upper extremity aneurysms were more likely to be reintervention-free than those in the lower extremities (p=0.01). In this series, resection or ligation of peripheral mycotic aneurysms without revascularization was well tolerated. With close follow-up of these patients, resection or ligation may obviate the more extensive initial revascularization procedures in these infected fields. Copyright © 2018 Elsevier Inc. All rights reserved.

Point Set Denoising Using Bootstrap-Based Radial Basis Function.

PubMed

Liew, Khang Jie; Ramli, Ahmad; Abd Majid, Ahmad

2016-01-01

This paper examines the application of a bootstrap test error estimation of radial basis functions, specifically thin-plate spline fitting, in surface smoothing. The presence of noisy data is a common issue of the point set model that is generated from 3D scanning devices, and hence, point set denoising is one of the main concerns in point set modelling. Bootstrap test error estimation, which is applied when searching for the smoothing parameters of radial basis functions, is revisited. The main contribution of this paper is a smoothing algorithm that relies on a bootstrap-based radial basis function. The proposed method incorporates a k-nearest neighbour search and then projects the point set to the approximated thin-plate spline surface. Therefore, the denoising process is achieved, and the features are well preserved. A comparison of the proposed method with other smoothing methods is also carried out in this study.

Modeling multivariate time series on manifolds with skew radial basis functions.

PubMed

Jamshidi, Arta A; Kirby, Michael J

2011-01-01

We present an approach for constructing nonlinear empirical mappings from high-dimensional domains to multivariate ranges. We employ radial basis functions and skew radial basis functions for constructing a model using data that are potentially scattered or sparse. The algorithm progresses iteratively, adding a new function at each step to refine the model. The placement of the functions is driven by a statistical hypothesis test that accounts for correlation in the multivariate range variables. The test is applied on training and validation data and reveals nonstatistical or geometric structure when it fails. At each step, the added function is fit to data contained in a spatiotemporally defined local region to determine the parameters--in particular, the scale of the local model. The scale of the function is determined by the zero crossings of the autocorrelation function of the residuals. The model parameters and the number of basis functions are determined automatically from the given data, and there is no need to initialize any ad hoc parameters save for the selection of the skew radial basis functions. Compactly supported skew radial basis functions are employed to improve model accuracy, order, and convergence properties. The extension of the algorithm to higher-dimensional ranges produces reduced-order models by exploiting the existence of correlation in the range variable data. Structure is tested not just in a single time series but between all pairs of time series. We illustrate the new methodologies using several illustrative problems, including modeling data on manifolds and the prediction of chaotic time series.

Hemodynamic and arterial stiffness differences between African-Americans and Caucasians after maximal exercise.

PubMed

Yan, Huimin; Ranadive, Sushant M; Heffernan, Kevin S; Lane, Abbi D; Kappus, Rebecca M; Cook, Marc D; Wu, Pei-Tzu; Sun, Peng; Harvey, Idethia S; Woods, Jeffrey A; Wilund, Kenneth R; Fernhall, Bo

2014-01-01

African-American (AA) men have higher arterial stiffness and augmentation index (AIx) than Caucasian-American (CA) men. Women have greater age-associated increases in arterial stiffness and AIx than men. This study examined racial and sex differences in arterial stiffness and central hemodynamics at rest and after an acute bout of maximal exercise in young healthy individuals. One hundred young, healthy individuals (28 AA men, 24 AA women, 25 CA men, and 23 CA women) underwent measurements of aortic blood pressure (BP) and arterial stiffness at rest and 15 and 30 min after an acute bout of graded maximal aerobic exercise. Aortic BP and AIx were derived from radial artery applanation tonometry. Aortic stiffness (carotid-femoral) was measured via pulse wave velocity. Aortic stiffness was increased in AA subjects but not in CA subjects (P < 0.05) after an acute bout of maximal cycling exercise, after controlling for body mass index. Aortic BP decreased after exercise in CA subjects but not in AA subjects (P < 0.05). Women exhibited greater reductions in AIx after maximal aerobic exercise compared with men (P < 0.05). In conclusion, race and sex impact vascular and central hemodynamic responses to exercise. Young AA and CA subjects exhibited differential responses in central stiffness and central BP after acute maximal exercise. Premenopausal women had greater augmented pressure at rest and after maximal aerobic exercise than men. Future research is needed to examine the potential mechanisms.

Hemodynamic and arterial stiffness differences between African-Americans and Caucasians after maximal exercise

PubMed Central

Ranadive, Sushant M.; Heffernan, Kevin S.; Lane, Abbi D.; Kappus, Rebecca M.; Cook, Marc D.; Wu, Pei-Tzu; Sun, Peng; Harvey, Idethia S.; Woods, Jeffrey A.; Wilund, Kenneth R.; Fernhall, Bo

2013-01-01

African-American (AA) men have higher arterial stiffness and augmentation index (AIx) than Caucasian-American (CA) men. Women have greater age-associated increases in arterial stiffness and AIx than men. This study examined racial and sex differences in arterial stiffness and central hemodynamics at rest and after an acute bout of maximal exercise in young healthy individuals. One hundred young, healthy individuals (28 AA men, 24 AA women, 25 CA men, and 23 CA women) underwent measurements of aortic blood pressure (BP) and arterial stiffness at rest and 15 and 30 min after an acute bout of graded maximal aerobic exercise. Aortic BP and AIx were derived from radial artery applanation tonometry. Aortic stiffness (carotid-femoral) was measured via pulse wave velocity. Aortic stiffness was increased in AA subjects but not in CA subjects (P < 0.05) after an acute bout of maximal cycling exercise, after controlling for body mass index. Aortic BP decreased after exercise in CA subjects but not in AA subjects (P < 0.05). Women exhibited greater reductions in AIx after maximal aerobic exercise compared with men (P < 0.05). In conclusion, race and sex impact vascular and central hemodynamic responses to exercise. Young AA and CA subjects exhibited differential responses in central stiffness and central BP after acute maximal exercise. Premenopausal women had greater augmented pressure at rest and after maximal aerobic exercise than men. Future research is needed to examine the potential mechanisms. PMID:24186094

l-Arginine Pathway Metabolites Predict Need for Intra-operative Shunt During Carotid Endarterectomy.

PubMed

Szabo, P; Lantos, J; Nagy, L; Keki, S; Volgyi, E; Menyhei, G; Illes, Z; Molnar, T

2016-12-01

Asymmetric dimethylarginine (ADMA) inhibits nitric oxide (NO) synthesis and is a marker of atherosclerosis. This study examined the correlation between pre-operative l-arginine and ADMA concentration during carotid endarterectomy (CEA), and jugular lactate indicating anaerobic cerebral metabolism, jugular S100B reflecting blood-brain barrier integrity, and with factors of surgical intervention. The concentration of l-arginine, ADMA, and symmetric dimethylarginine was measured in blood taken under regional anaesthesia from the radial artery of 55 patients prior to CEA. Blood gas parameters, concentration of lactate, and S100B were also serially measured in blood taken from both the radial artery and the jugular bulb before and after carotid clamping, and after release of the clamp. To estimate anaerobic metabolism, the jugulo-arterial ratio of CO 2 gap/oxygen extraction was calculated. Positive correlation was found between pre-operative ADMA levels and the ratio of jugulo-arterial CO 2 gap/oxygen extraction during clamp and reperfusion (p = .005 and p = .01, respectively). An inverse correlation was found between the pre-operative l-arginine concentration and jugular lactate at each time point (both p = .002). The critical pre-operative level of l-arginine was determined by receiver operator curve analysis. If l-arginine was below the cutoff value of 35 μmol/L, jugular S100B concentration was higher 24 h post-operatively (p = .03), and jugular lactate levels were increased during reperfusion (p = .02). The median pre-operative concentration of l-arginine was lower in patients requiring an intra-operative shunt than in patients without need of shunt (median: 30.3 μmol/L [interquartile range 24.4-34.4 μmol/L] vs. 57.6 μmol/L [interquartile range 42.3-74.5 μmol/L]; p = .002). High pre-operative ADMA concentration predicts poor cerebral perfusion indicated by elevated jugulo-arterial CO 2 gap/oxygen extraction. Low pre-operative l-arginine concentration predicts the need for a shunt. The inverse correlation between pre-operative l-arginine concentration and both jugular lactate and S100B during carotid clamping suggests a protective role of the NO donor l-arginine. Copyright © 2016 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.

Peritumoral Artery Scoring System: a Novel Scoring System to Predict Renal Function Outcome after Laparoscopic Partial Nephrectomy.

PubMed

Zhang, Ruiyun; Wu, Guangyu; Huang, Jiwei; Shi, Oumin; Kong, Wen; Chen, Yonghui; Xu, Jianrong; Xue, Wei; Zhang, Jin; Huang, Yiran

2017-06-06

The present study aimed to assess the impact of peritumoral artery characteristics on renal function outcome prediction using a novel Peritumoral Artery Scoring System based on computed tomography arteriography. Peritumoral artery characteristics and renal function were evaluated in 220 patients who underwent laparoscopic partial nephrectomy and then validate in 51 patients with split and total glomerular filtration rate (GFR). In particular, peritumoral artery classification and diameter were measured to assign arteries into low, moderate, and high Peritumoral Artery Scoring System risk categories. Univariable and multivariable logistic regression analyses were then used to determine risk factors for major renal functional decline. The Peritumoral Artery Scoring System and four other nephrometry systems were compared using receiver operating characteristic curve analysis. The Peritumoral Artery Scoring System was significantly superior to the other systems for predicting postoperative renal function decline (p < 0.001). In receiver operating characteristic analysis, our category system was a superior independent predictor of estimated glomerular filtration rate (eGFR) decline (area-under-the-curve = 0.865, p < 0.001) and total GFR decline (area-under-the-curve = 0.796, p < 0.001), and split GFR decline (area-under-the-curve = 0.841, p < 0.001). Peritumoral artery characteristics were independent predictors of renal function outcome after laparoscopic partial nephrectomy.

Aortic Blood Flow Reversal Determines Renal Function: Potential Explanation for Renal Dysfunction Caused by Aortic Stiffening in Hypertension.

PubMed

Hashimoto, Junichiro; Ito, Sadayoshi

2015-07-01

Aortic stiffness determines the glomerular filtration rate (GFR) and predicts the progressive decline of the GFR. However, the underlying pathophysiological mechanism remains obscure. Recent evidence has shown a close link between aortic stiffness and the bidirectional (systolic forward and early diastolic reverse) flow characteristics. We hypothesized that the aortic stiffening-induced renal dysfunction is attributable to altered central flow dynamics. In 222 patients with hypertension, Doppler velocity waveforms were recorded at the proximal descending aorta to calculate the reverse/forward flow ratio. Tonometric waveforms were recorded to measure the carotid-femoral (aortic) and carotid-radial (peripheral) pulse wave velocities, to estimate the aortic pressure from the radial waveforms, and to compute the aortic characteristic impedance. In addition, renal hemodynamics was evaluated by duplex ultrasound. The estimated GFR was inversely correlated with the aortic pulse wave velocity, reverse/forward flow ratio, pulse pressure, and characteristic impedance, whereas it was not correlated with the peripheral pulse wave velocity or mean arterial pressure. The association between aortic pulse wave velocity and estimated GFR was independent of age, diabetes mellitus, hypercholesterolemia, and antihypertensive medication. However, further adjustment for the aortic reverse/forward flow ratio and pulse pressure substantially weakened this association, and instead, the reverse/forward flow ratio emerged as the strongest determinant of estimated GFR (P=0.001). A higher aortic reverse/forward flow ratio was also associated with lower intrarenal forward flow velocities. These results suggest that an increase in aortic flow reversal (ie, retrograde flow from the descending thoracic aorta toward the aortic arch), caused by aortic stiffening and impedance mismatch, reduces antegrade flow into the kidney and thereby deteriorates renal function. © 2015 American Heart Association, Inc.

Abductor pollicis longus: a case of mistaken identity.

PubMed

Elliott, B G

1992-08-01

Abductor pollicis longus, long regarded as a motor for the thumb, is anatomically and functionally a radial deviator of the wrist and should be so named. The abductor carpi is proposed. If the other radial deviators of the wrist are acting this tendon can be selectively utilized as a transfer without loss of function. Reflex spasm of this muscle probably plays an important role in the radial deviation deformity seen in the rheumatoid hand.

Connective tissue-activating peptide III: a novel blood biomarker for early lung cancer detection.

PubMed

Yee, John; Sadar, Marianne D; Sin, Don D; Kuzyk, Michael; Xing, Li; Kondra, Jennifer; McWilliams, Annette; Man, S F Paul; Lam, Stephen

2009-06-10

There are no reliable blood biomarkers to detect early lung cancer. We used a novel strategy that allows discovery of differentially present proteins against a complex and variable background. Mass spectrometry analyses of paired pulmonary venous-radial arterial blood from 16 lung cancer patients were applied to identify plasma proteins potentially derived from the tumor microenvironment. Two differentially expressed proteins were confirmed in 64 paired venous-arterial blood samples using an immunoassay. Twenty-eight pre- and postsurgical resection peripheral blood samples and two independent, blinded sets of plasma from 149 participants in a lung cancer screening study (49 lung cancers and 100 controls) and 266 participants from the National Heart Lung and Blood Institute Lung Health Study (45 lung cancer and 221 matched controls) determined the accuracy of the two protein markers to detect subclinical lung cancer. Connective tissue-activating peptide III (CTAP III)/ neutrophil activating protein-2 (NAP-2) and haptoglobin were identified to be significantly higher in venous than in arterial blood. CTAP III/NAP-2 levels decreased after tumor resection (P = .01). In two independent population cohorts, CTAP III/NAP-2 was significantly associated with lung cancer and improved the accuracy of a lung cancer risk prediction model that included age, smoking, lung function (FEV(1)), and an interaction term between FEV(1) and CTAP III/NAP-2 (area under the curve, 0.84; 95% CI, 0.77 to 0.91) compared to CAPIII/NAP-2 alone. We identified CTAP III/NAP-2 as a novel biomarker to detect preclinical lung cancer. The study underscores the importance of applying blood biomarkers as part of a multimodal lung cancer risk prediction model instead of as stand-alone tests.

Effect of American ginseng (Panax quinquefolius L.) on arterial stiffness in subjects with type-2 diabetes and concomitant hypertension.

PubMed

Mucalo, Iva; Jovanovski, Elena; Rahelić, Dario; Božikov, Velimir; Romić, Zeljko; Vuksan, Vladimir

2013-10-28

Substantial pre-clinical and some clinical data are available showing that Asian ginseng (Panax ginseng C.A. Meyer) varieties or its particular ginsenosides exert a vasodilatating effect, thus may modulate vascular function. However, the clinical evidence for American ginseng (Panax quinquefolius L.) is scarce. Therefore, this study evaluates the effect of American ginseng (AG) on arterial stiffness, as measured by augmentation index (AI), and blood pressure (BP), in type 2 diabetes patients with concomitant hypertension. Using a double-blind, placebo-controlled, parallel design, each participant was randomized to either the selected AG extract or placebo at daily dose of 3g for 12 weeks as an adjunct to their usual antihypertensive and anti-diabetic therapy (diet and/or medications). AI and BP were measured by applanation tonometry at baseline and after 12 weeks of treatment. A total of 64 individuals with well-controlled essential hypertension and type 2 diabetes (gender: 22 M:42 F, age:63 ± 9.3 years, BP: 145 ± 10.8/84 ± 8.0 mmHg, HbA1c: 7.0 ± 1.3%, fasting blood glucose (FBG): 8.1 ± 2.3 mmol/L) completed the study. Compared to placebo, 3g of AG significantly lowered radial AI by 5.3% (P=0.041) and systolic BP by 11.7% (P<0.001) at 12 weeks. No effect was observed with diastolic BP. Addition of AG extract to conventional therapy in diabetes with concomitant hypertension improved arterial stiffness and attenuated systolic BP, thus warrants further investigation on long-term endothelial parameters before recommended as an adjunct treatment. © 2013 Elsevier Ireland Ltd. All rights reserved.

Evidence of cardiac functional reserve upon exhaustion during incremental exercise to determine VO2max.

PubMed

Elliott, Adrian D; Skowno, Justin; Prabhu, Mahesh; Noakes, Timothy David; Ansley, Les

2015-01-01

There remains considerable debate regarding the limiting factor(s) for maximal oxygen uptake (VO2max). Previous studies have shown that the central circulation may be the primary limiting factor for VO2max and that cardiac work increases beyond VO2max. We sought to evaluate whether the work of the heart limits VO2max during upright incremental cycle exercise to exhaustion. Eight trained men completed two incremental exercise trials, each terminating with exercise at two different rates of work eliciting VO2max (MAX and SUPRAMAX). During each exercise trial we continuously recorded cardiac output using pulse-contour analysis calibrated with a lithium dilution method. Intra-arterial pressure was recorded from the radial artery while pulmonary gas exchange was measured continuously for an assessment of oxygen uptake. The workload during SUPRAMAX (mean±SD: 346.5±43.2 W) was 10% greater than that achieved during MAX (315±39.3 W). There was no significant difference between MAX and SUPRAMAX for Q (28.7 vs 29.4 L/min) or VO2 (4.3 vs 4.3 L/min). Mean arterial pressure was significantly higher during SUPRAMAX, corresponding to a higher cardiac power output (8.1 vs 8.5 W; p<0.06). Despite similar VO2 and Q, the greater cardiac work during SUPRAMAX supports the view that the heart is working submaximally at exhaustion during an incremental exercise test (MAX). Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Comparative Analysis of Arterial Parameters Variations Associated with Inter-Individual Variations in Peripheral and Aortic Blood Pressure: Cross-Sectional Study in Healthy Subjects Aged 2-84 years.

PubMed

Zócalo, Yanina; Curcio, Santiago; García-Espinosa, Victoria; Chiesa, Pedro; Giachetto, Gustavo; Bia, Daniel

2017-12-01

The association between arterial parameters and blood pressure (BP) interindividual variations could depend on the arterial segment, BP component (systolic, SBP; diastolic, DBP; pulse pressure, PP) and/or on whether central (cBP) or peripheral (pBP) BP variations are considered. To assess and compare arterial parameters variations associated with interindividual variations in cBP and pBP. Healthy subjects (n = 923; 488 males, 2-84 years) were included. pBP and cBP waves were obtained (Mobil-O-Graph; SphygmoCor). Arterial diameter, intima-media thickness, local elastic modulus (carotid, CEM; brachial, BEM; femoral, FEM) and regional (carotid-radial and carotid-femoral pulse wave velocity; crPWV and cfPWV) arterial stiffness were determined. Associations between BP and arterial parameters interindividual variations were analyzed and compared (correlations; linear regressions; slopes comparisons) considering data transformed into z-scores. Given a variation in z-cSBP or z-pSBP, z-CEM, z-FEM and z-cfPWV (stiffness indexes), were among the parameters with major BP-associated variations. z-crPWV and z-cfPWV, rather than local stiffness indexes were the parameters with major variations associated with z-DBP variations. z-cPP or z-pPP were associated with z-CEM and z-FEM variations, but not with brachial or regional stiffness variations. Most of the arterial parameters-BP slopes did not show significant differences when considering a variation in z-cSBP and z-pSBP. z-CEM and z-FEM were mainly associated with z-cPP and z-pPP variations, respectively. Disregard of age and sex, the variations in arterial parameters associated with BP interindividual variations showed differences depending on whether variations were central or peripheral; in SBP, DBP or PP and depending on the arterial segment considered.

Retinal oximetry measures systemic hypoxia in central nervous system vessels in chronic obstructive pulmonary disease

PubMed Central

Bragason, David; Hardarson, Sveinn Hakon; Vacchiano, Charles; Gislason, Thorarinn; Kristjansdottir, Jona Valgerdur; Kristjansdottir, Gudrun; Stefánsson, Einar

2017-01-01

Background Determination of the blood oxyhemoglobin saturation in the retinal vessels of the eye can be achieved through spectrophotometric retinal oximetry which provides access to the state of oxyhemoglobin saturation in the central nervous system circulation. The purpose of this study was to test the capability of the Oxymap T1 oximeter to detect systemic hypoxemia and the effect of supplemental oxygen on retinal vessel oxyhemoglobin saturation. Methods Oxygen saturation of hemoglobin in retinal arterioles and venules was measured in 11 subjects with severe chronic obstructive pulmonary disease (COPD) on long term oxygen therapy. Measurements were made with and without their daily supplemental oxygen. Eleven healthy age and gender matched subjects were measured during ambient air breathing for comparison of oxyhemoglobin saturation in retinal arterioles and venules. Retinal arteriolar oxyhemoglobin saturation in COPD subjects inspiring ambient air was compared with finger pulse oximetry and blood samples from radial artery. Results COPD subjects had significantly lower oxyhemoglobin saturation during ambient air breathing than healthy controls in both retinal arterioles (87.2%±4.9% vs. 93.4%±4.3%, p = 0.02; n = 11) and venules (45.0%±10.3% vs. 55.2%±5.5%, p = 0.01). Administration of their prescribed supplemental oxygen increased oxyhemoglobin saturation in retinal arterioles (87.2%±4.9% to 89.5%±6.0%, p = 0.02) but not in venules (45.0%±10.3% to 46.7%±12.8%, p = 0.3). Retinal oximetry values were slightly lower than radial artery blood values (mean percentage points difference = -5.0±5.4, 95% CI: -15.68 to 5.67) and finger pulse oximetry values (-3.1±5.5, 95% CI: -14.05 to 7.84). Conclusions The noninvasive Oxymap T1 retinal oximetry detects hypoxemia in central nervous system vessels in patients with severe COPD compared with healthy controls. The instrument is sensitive to changes in oxygen breathing but displays slightly lower measures than finger pulse oximetry or radial artery measures. With further technological improvement, retinal oximetry may offer noninvasive “on-line” measurement of oxygen levels in central circulation in general anesthesia and critically ill patients. PMID:28328974

The Radial Distribution Function (RDF) of Amorphous Selenium Obtained through the Vacuum Evaporator

DOE Office of Scientific and Technical Information (OSTI.GOV)

Guda, Bardhyl; Dede, Marie

2010-01-21

After the amorphous selenium obtained through the vacuum evaporator, the relevant diffraction intensity is taken and its processing is made. Further on the interferential function is calculated and the radial density function is defined. For determining these functions are used two methods, which were compared with each other and finally are received results for amorphous selenium RDF.

Zernike Basis to Cartesian Transformations

NASA Astrophysics Data System (ADS)

Mathar, R. J.

2009-12-01

The radial polynomials of the 2D (circular) and 3D (spherical) Zernike functions are tabulated as powers of the radial distance. The reciprocal tabulation of powers of the radial distance in series of radial polynomials is also given, based on projections that take advantage of the orthogonality of the polynomials over the unit interval. They play a role in the expansion of products of the polynomials into sums, which is demonstrated by some examples. Multiplication of the polynomials by the angular bases (azimuth, polar angle) defines the Zernike functions, for which we derive transformations to and from the Cartesian coordinate system centered at the middle of the circle or sphere.

Does interruption of the artery of Adamkiewicz during total en bloc spondylectomy affect neurologic function?

PubMed

Murakami, Hideki; Kawahara, Norio; Tomita, Katsuro; Demura, Satoru; Kato, Satoshi; Yoshioka, Katsuhito

2010-10-15

A retrospective review of patients with interruption of the artery of Adamkiewicz during total en bloc spondylectomy (TES). To assess neurologic function after interruption of the artery of Adamkiewicz in TES. The most important feeding artery of the thoracolumbar spinal cord is the great anterior radiculomedullary artery, also called the artery of Adamkiewicz. The artery of Adamkiewicz supplies the lower two-thirds of the spinal cord via the anterior spinal artery. It is naturally believed among spine surgeons that interruption of the artery of Adamkiewicz during surgeries is absolutely contraindicated. However, it is necessary to sacrifice the artery of Adamkiewicz during TES, when the tumor, by chance, exists at the level of the artery of Adamkiewicz. Between 1990 and 2009, we have performed 180 cases of TES. All cases except for few emergency cases received preoperative embolization. The artery of Adamkiewicz was verified by angiography of the segmental arteries. There were 15 patients in which the artery of Adamkiewicz was found at the levels of resected vertebrae. Interruption of the artery was performed during surgery in these 15 cases. Neurologic function was analyzed retrospectively. Of the 15 patients, the Frankel grade before surgery was C in 1, D in 5, and E in 9. At follow-up, the Frankel grade was D in 1 and E in 14. There were no cases of neurologic deterioration or paralysis after TES. On the basis of our results of TES on up to 3 vertebrae, interruption of the artery of Adamkiewicz for TES does not adversely affect neurologic function. We advocate strongly that our surgeons are allowed to sacrifice up to 3 pairs of segmental arteries, even including the artery of Adamkiewicz, if necessary.

Endothelium Preserving Microwave Treatment for Atherosclerosis

NASA Technical Reports Server (NTRS)

Carl, James R. (Inventor); Arndt, G. Dickey (Inventor); Fink, Patrick W. (Inventor); Beer, N. Reginald (Inventor); Henry, Phillip D. (Inventor); Pacifico, Antonio (Inventor); Raffoul, George W. (Inventor)

2000-01-01

Method and apparatus are provided to treat atherosclerosis wherein the artery is partially closed by dilating the artery while preserving the vital and sensitive endothelial layer thereof Microwave energy having a frequency from 3 GHz to 300 GHz is propagated into the arterial wall to produce a desired temperature profile therein at tissue depths sufficient for thermally necrosing connective tissue and softening fatty and waxy plaque while limiting heating of surrounding tissues including the endothelial laser and/or other healthy tissue, organs, and blood. The heating period for raising the temperature a potentially desired amount, about 20 C., within the atherosclerotic lesion may be less than about one second. In one embodiment of the invention, a radically beveled waveguide antenna is used to deliver microwave energy at frequencies from 25 GHz or 30 GHz to about 300 GHz and is focused towards a particular radial sector of the artery. Because the atherosclerotic lesions are often asymmetrically disposed, directable of focussed heating preserves healthy sectors of the artery and applies energy to the asymmetrically positioned lesion faster than a non-directed beam. A computer simulation predicts isothermic temperature profiles for the given conditions and man be used in selecting power, pulse duration, beam width, and frequency of operation to maximize energy deposition and control heat rise within the atherosclerotic lesion without harming healthy tissues or the sensitive endothelium cells.

Endothelium Preserving Microwave Treatment for Atherosclerosis

NASA Technical Reports Server (NTRS)

Carl, James R. (Inventor); Arndt, G. Dickey (Inventor); Fink, Patrick W. (Inventor); Beer, N. Reginald (Inventor); Henry, Phillip D. (Inventor); Pacifico, Antonio (Inventor); Raffoul, George W. (Inventor)

2001-01-01

Method and apparatus are provided to treat atherosclerosis wherein the artery is partially closed by dilating the artery while preserving the vital and sensitive endothelial layer thereof. Microwave energy having a frequency from 3 GHz to 300 GHz is propagated into the arterial wall to produce a desired temperature profile therein at tissue depths sufficient for thermally necrosing connective tissue and softening fatty and waxy plaque while limiting heating of surrounding tissues including the endothelial layer and/or other healthy tissue, organs, and blood. The heating period for raising the temperature a potentially desired amount, about 20 C. within the atherosclerotic lesion may be less than about one second. In one embodiment of the invention, a radically beveled waveguide antenna is used to deliver microwave energy at frequencies from 25 GHz or 30 GHz to about 300 GHz and is focused towards a particular radial sector of the artery. Because the atherosclerotic lesions are often asymmetrically disposed directable or focussed heating preserves healthy sectors of the artery and applies energy to the asymmetrically positioned lesion faster than a non-directed beam. A computer simulation predicts isothermic temperature profiles for the given conditions and may be used in selecting power, pulse duration, beam width, and frequency of operation to maximize energy deposition and control heat rise within the atherosclerotic lesion without harming healthy tissues or the sensitive endothelium cells.

A mechanical argument for the differential performance of coronary artery grafts.

PubMed

Prim, David A; Zhou, Boran; Hartstone-Rose, Adam; Uline, Mark J; Shazly, Tarek; Eberth, John F

2016-02-01

Coronary artery bypass grafting (CABG) acutely disturbs the homeostatic state of the transplanted vessel making retention of graft patency dependent on chronic remodeling processes. The time course and extent to which remodeling restores vessel homeostasis will depend, in part, on the nature and magnitude of the mechanical disturbances induced upon transplantation. In this investigation, biaxial mechanical testing and histology were performed on the porcine left anterior descending artery (LAD) and analogs of common autografts, including the internal thoracic artery (ITA), radial artery (RA), great saphenous vein (GSV) and lateral saphenous vein (LSV). Experimental data were used to quantify the parameters of a structure-based constitutive model enabling prediction of the acute vessel mechanical response pre-transplantation and under coronary loading conditions. A novel metric Ξ was developed to quantify mechanical differences between each graft vessel in situ and the LAD in situ, while a second metric Ω compares the graft vessels in situ to their state under coronary loading. The relative values of these metrics among candidate autograft sources are consistent with vessel-specific variations in CABG clinical success rates with the ITA as the superior and GSV the inferior graft choices based on mechanical performance. This approach can be used to evaluate other candidate tissues for grafting or to aid in the development of synthetic and tissue engineered alternatives. Copyright © 2015 Elsevier Ltd. All rights reserved.

Endothelium Preserving Microwave Treatment for Atherosclerosis

NASA Technical Reports Server (NTRS)

Carl, James R. (Inventor); Arndt, Dickey (Inventor); Fink, Patrick W. (Inventor); Beer, Reginald (Inventor); Henry, Phillip D. (Inventor); Pacifico, Antonio (Inventor); Raffoul, George W. (Inventor)

2002-01-01

Method and apparatus are provided to treat atherosclerosis wherein the artery is partially closed by dilating the artery while preserving the vital and sensitive endothelial layer thereof. Microwave energy having a frequency from 3 GHz to 300 GHz is propagated into the arterial wall to produce a desired temperature profile therein at tissue depths sufficient for thermally necrosing connective tissue and softening fatty and waxy plaque while limiting heating of surrounding tissues including the endothelial layer and/or other healthy tissue, organs, and blood. The heating period for raising the temperature a potentially desired amount, about 20 C. within the atherosclerotic lesion may be less than about one second. In one embodiment of the invention, a radically beveled waveguide antenna is used to deliver microwave energy at frequencies from 25 GHz or 30 GHz to about 300 GHz and is focused towards a particular radial sector of the artery. Because the atherosclerotic lesions are often asymmetrically disposed, directable or focussed heating preserves healthy sectors or the artery and applies energy to the asymmetrically positioned lesion faster than a non-directed bean. A computer simulation predicts isothermic temperature profiles for the given conditions and may be used in selecting power, pulse duration, beam width, and frequency of operation to maximize energy deposition and control heat rise within the atherosclerotic lesion without harming healthy tissues or the sensitive endothelium cells.

In vivo time-lapse imaging of cell proliferation and differentiation in the optic tectum of Xenopus laevis tadpoles

PubMed Central

Bestman, Jennifer E.; Lee-Osbourne, Jane; Cline, Hollis T.

2012-01-01

We analyzed the function of neural progenitors in the developing CNS of Xenopus laevis tadpoles using in vivo time-lapse confocal microscopy to collect images through the tectum at intervals of 2 to 24 hours over 3 days. Neural progenitor cells were labeled with fluorescent protein reporters based on expression of endogenous Sox2 transcription factor. With this construct, we identified Sox2-expressing cells as radial glia and as a component of the progenitor pool of cells in the developing tectum that gives rise to neurons and other radial glia. Lineage analysis of individual radial glia and their progeny demonstrated that less than 10% of radial glia undergo symmetric divisions resulting in two radial glia, while the majority of radial glia divide asymmetrically to generate neurons and radial glia. Time-lapse imaging revealed the direct differentiation of radial glia into neurons. Although radial glia may guide axons as they navigate to superficial tectum, we find no evidence that radial glia function as a scaffold for neuronal migration at early stages of tectal development. Over three days, the number of labeled cells increased 20%, as the fraction of radial glia dropped and the proportion of neuronal progeny increased to approximately 60% of the labeled cells. Tadpoles provided with short-term visual enhancement generated significantly more neurons, with a corresponding decrease in cell proliferation. Together these results demonstrate that radial glial cells are neural progenitors in the developing optic tectum and reveal that visual experience increases the proportion of neurons generated in an intact animal. PMID:22113462

[Obesity as pathology of adipocytes: number of cells, volume of arterial bloodstream,local pools of circulation in vivo, natriuretic peptides and arterial hypertension].

PubMed

Titov, V N; Dmitriev, V A

2015-03-01

The non-specific systemic biological reaction of arterial pressure from the level of organism. vasomotor center and proximal section of arterial bloodstream is appealed to compensate disorders of metabolism and microcirculation in distal section of arteries. This phenomenon occurs in several cases. The primarily local disorders of metabolism at autocrine level, physiological (aphysiological) death of cells, "littering" of intercellular medium become the cause of disorder of microcirculation in paracrin cenosises and deteriorate realization of biological functions of homeostasis, trophology, endoecology and adaptation. The local compensation of affected perfusion in paracrin cenosises at the expense of function of peripheral peristaltic pumps, redistribution of local bloodflow in biological reaction of endothelium-depended vaso-dilation has no possibility to eliminate disorders in realization of biological functions. The systemic increase of arterial pressure under absence of specific symptoms of symptomatic arterial hypertension is a test to detect disorder of biological functions of homeostasis, trophology, biological function of endoecology and adaptation. Allforms of arterial hypertension develop by common algorithm independently from causes of disorders of blood flow, microcirculation in distal section of arteries. The non-specific systemic compensation ofdisorders of metabolism from level of organism, in proximal section of arterial bloodstream always is the same one and results in aphysiological alterations in organs-targets. To comprehend etiological characteristics of common pathogenesis of arterial hypertension is possible in case of application of such technically complicated and still unclear in differential diagnostic of deranged functions modes of metabolomics.

TESTING THE EFFECTS OF EXPANSION ON SOLAR WIND TURBULENCE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vech, Daniel; Chen, Christopher H K, E-mail: dvech@umich.edu

2016-11-20

We present a multi-spacecraft approach to test the predictions of recent studies on the effect of solar wind expansion on the radial spectral, variance, and local 3D anisotropies of the turbulence. We found that on small scales (5000–10,000 km) the power levels of the B-trace structure functions do not depend on the sampling direction with respect to the radial suggesting that on this scale the effect of expansion is small possibly due to fast turbulent timescales. On larger scales (110–135 R{sub E}), the fluctuations of the radial magnetic field component are reduced by ∼20% compared to the transverse (perpendicular tomore » radial) ones, which could be due to expansion confining the fluctuations into the plane perpendicular to radial. For the local 3D spectral anisotropy, the B-trace structure functions showed dependence on the sampling direction with respect to radial. The anisotropy in the perpendicular plane is reduced when the increments are taken perpendicular with respect to radial, which could be an effect of expansion.« less

Various clinical scenarios leading to development of the string sign of the internal thoracic artery after coronary bypass surgery: the role of competitive flow, a case series.

PubMed

Kolozsvari, Rudolf; Galajda, Zoltan; Ungvari, Tamas; Szabo, Gabor; Racz, Ildikó; Szerafin, Tamás; Herzfeld, István; Edes, István; Peterffy, Arpad; Koszegi, Zsolt

2012-01-30

The left internal mammary artery (LIMA) is the choice for grafting of the left anterior descending coronary artery (LAD). One possible mechanism of the rare graft failure involve the presence of competitive flow. 105 patients who had undergone coronary bypass grafting between 1998 and 2000 were included in this observational study. The recatheterizations were performed 28 months after the operations. The rate of patency the LIMA grafts was determined, and the cases with graft failure were analyzed. The LIMA graft was patent in 99 patients (94%). Six patients (6%) exhibited diffuse involution of the graft (string sign). The string sign was always associated with competitive flow as the basis of the LIMA graft involution. In one case quantitative re-evaluation of the preoperative coronary angiography revealed merely less than 50% diameter stenosis on the LAD with a nonligated side-branch of the LIMA. At recatheterization in two patients the pressure wire measurements demonstrated only a non-significant decrease of the fractional flow reserve (0.83 and 0.89), despite the 53% and 57% diameter stenosis in the angiogram. Another patient displayeda significant regression of the LAD lesion between the pre- and postoperative coronary angiography (from 76% to 44%) as the cause of the development of the competitive flow. In one instance, a radial artery graft on the LAD during a redo bypass operation resulted in competitive flow in the radial graft due to the greater diameter than that of the LIMA. In a further patient, competitive flow developed from a short sequential part of the LIMA graft between the nonsignificantly stenosed diagonal branch and the LAD, with involution of the main part of the graft to the diagonal branch. The most common cause of the development of the string sign of a LIMA graft due to competitive flow is overassessment of the lesion of the LAD. Regression of a previous lesion or some other neighboring graft can also cause the phenomenon.

Breath-hold imaging of the coronary arteries using Quiescent-Interval Slice-Selective (QISS) magnetic resonance angiography: pilot study at 1.5 Tesla and 3 Tesla.

PubMed

Edelman, Robert R; Giri, S; Pursnani, A; Botelho, M P F; Li, W; Koktzoglou, I

2015-11-23

Coronary magnetic resonance angiography (MRA) is usually obtained with a free-breathing navigator-gated 3D acquisition. Our aim was to develop an alternative breath-hold approach that would allow the coronary arteries to be evaluated in a much shorter time and without risk of degradation by respiratory motion artifacts. For this purpose, we implemented a breath-hold, non-contrast-enhanced, quiescent-interval slice-selective (QISS) 2D technique. Sequence performance was compared at 1.5 and 3 Tesla using both radial and Cartesian k-space trajectories. The left coronary circulation was imaged in six healthy subjects and two patients with coronary artery disease. Breath-hold QISS was compared with T2-prepared 2D balanced steady-state free-precession (bSSFP) and free-breathing, navigator-gated 3D bSSFP. Approximately 10 2.1-mm thick slices were acquired in a single ~20-s breath-hold using two-shot QISS. QISS contrast-to-noise ratio (CNR) was 1.5-fold higher at 3 Tesla than at 1.5 Tesla. Cartesian QISS provided the best coronary-to-myocardium CNR, whereas radial QISS provided the sharpest coronary images. QISS image quality exceeded that of free-breathing 3D coronary MRA with few artifacts at either field strength. Compared with T2-prepared 2D bSSFP, multi-slice capability was not restricted by the specific absorption rate at 3 Tesla and pericardial fluid signal was better suppressed. In addition to depicting the coronary arteries, QISS could image intra-cardiac structures, pericardium, and the aortic root in arbitrary slice orientations. Breath-hold QISS is a simple, versatile, and time-efficient method for coronary MRA that provides excellent image quality at both 1.5 and 3 Tesla. Image quality exceeded that of free-breathing, navigator-gated 3D MRA in a much shorter scan time. QISS also allowed rapid multi-slice bright-blood, diastolic phase imaging of the heart, which may have complementary value to multi-phase cine imaging. We conclude that, with further clinical validation, QISS might provide an efficient alternative to commonly used free-breathing coronary MRA techniques.

Validation of Noninvasive MOEMS-Assisted Measurement System Based on CCD Sensor for Radial Pulse Analysis

PubMed Central

Malinauskas, Karolis; Palevicius, Paulius; Ragulskis, Minvydas; Ostasevicius, Vytautas; Dauksevicius, Rolanas

2013-01-01

Examination of wrist radial pulse is a noninvasive diagnostic method, which occupies a very important position in Traditional Chinese Medicine. It is based on manual palpation and therefore relies largely on the practitioner′s subjective technical skills and judgment. Consequently, it lacks reliability and consistency, which limits practical applications in clinical medicine. Thus, quantifiable characterization of the wrist pulse diagnosis method is a prerequisite for its further development and widespread use. This paper reports application of a noninvasive CCD sensor-based hybrid measurement system for radial pulse signal analysis. First, artery wall deformations caused by the blood flow are calibrated with a laser triangulation displacement sensor, following by the measurement of the deformations with projection moiré method. Different input pressures and fluids of various viscosities are used in the assembled artificial blood flow system in order to test the performance of laser triangulation technique with detection sensitivity enhancement through microfabricated retroreflective optical element placed on a synthetic vascular graft. Subsequently, the applicability of double-exposure whole-field projection moiré technique for registration of blood flow pulses is considered: a computational model and representative example are provided, followed by in vitro experiment performed on a vascular graft with artificial skin atop, which validates the suitability of the technique for characterization of skin surface deformations caused by the radial pulsation. PMID:23609803

Validation of noninvasive MOEMS-assisted measurement system based on CCD sensor for radial pulse analysis.

PubMed

Malinauskas, Karolis; Palevicius, Paulius; Ragulskis, Minvydas; Ostasevicius, Vytautas; Dauksevicius, Rolanas

2013-04-22

Examination of wrist radial pulse is a noninvasive diagnostic method, which occupies a very important position in Traditional Chinese Medicine. It is based on manual palpation and therefore relies largely on the practitioner's subjective technical skills and judgment. Consequently, it lacks reliability and consistency, which limits practical applications in clinical medicine. Thus, quantifiable characterization of the wrist pulse diagnosis method is a prerequisite for its further development and widespread use. This paper reports application of a noninvasive CCD sensor-based hybrid measurement system for radial pulse signal analysis. First, artery wall deformations caused by the blood flow are calibrated with a laser triangulation displacement sensor, following by the measurement of the deformations with projection moiré method. Different input pressures and fluids of various viscosities are used in the assembled artificial blood flow system in order to test the performance of laser triangulation technique with detection sensitivity enhancement through microfabricated retroreflective optical element placed on a synthetic vascular graft. Subsequently, the applicability of double-exposure whole-field projection moiré technique for registration of blood flow pulses is considered: a computational model and representative example are provided, followed by in vitro experiment performed on a vascular graft with artificial skin atop, which validates the suitability of the technique for characterization of skin surface deformations caused by the radial pulsation.

Peripheral vascular dysfunction in migraine: a review

PubMed Central

2013-01-01

Numerous studies have indicated an increased risk of vascular disease among migraineurs. Alterations in endothelial and arterial function, which predispose to atherosclerosis and cardiovascular diseases, have been suggested as an important link between migraine and vascular disease. However, the available evidence is inconsistent. We aimed to review and summarize the published evidence about the peripheral vascular dysfunction of migraineurs. We systematically searched in BIOSIS, the Cochrane database, Embase, Google scholar, ISI Web of Science, and Medline to identify articles, published up to April 2013, evaluating the endothelial and arterial function of migraineurs. Several lines of evidence for vascular dysfunction were reported in migraineurs. Findings regarding endothelial function are particularly controversial since studies variously indicated the presence of endothelial dysfunction in migraineurs, the absence of any difference in endothelial function between migraineurs and non-migraineurs, and even an enhanced endothelial function in migraineurs. Reports on arterial function are more consistent and suggest that functional properties of large arteries are altered in migraineurs. Peripheral vascular function, particularly arterial function, is a promising non-invasive indicator of the vascular health of subjects with migraine. However, further targeted research is needed to understand whether altered arterial function explains the increased risk of vascular disease among patients with migraine. PMID:24083826

Mechanical function near defects in an aligned nanofiber composite is preserved by inclusion of disorganized layers: Insight into meniscus structure and function.

PubMed

Bansal, Sonia; Mandalapu, Sai; Aeppli, Céline; Qu, Feini; Szczesny, Spencer E; Mauck, Robert L; Zgonis, Miltiadis H

2017-07-01

The meniscus is comprised of circumferentially aligned fibers that resist the tensile forces within the meniscus (i.e., hoop stress) that develop during loading of the knee. Although these circumferential fibers are severed by radial meniscal tears, tibial contact stresses do not increase until the tear reaches ∼90% of the meniscus width, suggesting that the severed circumferential fibers still bear load and maintain the mechanical functionality of the meniscus. Recent data demonstrates that the interfibrillar matrix can transfer strain energy to disconnected fibrils in tendon fascicles. In the meniscus, interdigitating radial tie fibers, which function to stabilize and bind the circumferential fibers together, are hypothesized to function in a similar manner by transmitting load to severed circumferential fibers near a radial tear. To test this hypothesis, we developed an engineered fibrous analog of the knee meniscus using poly(ε-caprolactone) to create aligned scaffolds with variable amounts of non-aligned elements embedded within the scaffold. We show that the tensile properties of these scaffolds are a function of the ratio of aligned to non-aligned elements, and change in a predictable fashion following a simple mixture model. When measuring the loss of mechanical function in scaffolds with a radial tear, compared to intact scaffolds, the decrease in apparent linear modulus was reduced in scaffolds containing non-aligned layers compared to purely aligned scaffolds. Increased strains in areas adjacent to the defect were also noted in composite scaffolds. These findings indicate that non-aligned (disorganized) elements interspersed within an aligned network can improve overall mechanical function by promoting strain transfer to nearby disconnected fibers. This finding supports the notion that radial tie fibers may similarly promote tear tolerance in the knee meniscus, and will direct changes in clinical practice and provide guidance for tissue engineering strategies. The meniscus is a complex fibrous tissue, whose architecture includes radial tie fibers that run perpendicular to and interdigitate with the predominant circumferential fibers. We hypothesized that these radial elements function to preserve mechanical function in the context of interruption of circumferential bundles, as would be the case in a meniscal tear. To test this hypothesis, we developed a biomaterial analog containing disorganized layers enmeshed regularly throughout an otherwise aligned network. Using this material formulation, we showed that strain transmission is improved in the vicinity of defects when disorganized fiber layers were present. This supports the idea that radial elements within the meniscus improve function near a tear, and will guide future clinical interventions and the development of engineered replacements. Copyright © 2017 Acta Materialia Inc. All rights reserved.

Coronary Artery Bypass Grafting in Diabetic Patients: Complete Arterial versus Internal Thoracic Artery and Sequential Vein Grafts-A Propensity-Score Matched Analysis.

PubMed

Kunihara, Takashi; Wendler, Olaf; Heinrich, Kerstin; Nomura, Ryota; Schäfers, Hans-Joachim

2018-06-20

 The optimal choice of conduit and configuration for coronary artery bypass grafting (CABG) in diabetic patients remains somewhat controversial, even though arterial grafts have been proposed as superior. We attempted to clarify the role of complete arterial revascularization using the left internal thoracic artery (LITA) and the radial artery (RA) alone in "T-Graft" configuration on long-term outcome.  From 1994 to 2001, 104 diabetic patients with triple vessel disease underwent CABG using LITA/RA "T-Grafts" (Group-A). Using propensity-score matching, 104 patients with comparable preoperative characteristics who underwent CABG using LITA and one sequential vein graft were identified (Group-V). Freedom from all causes of death, cardiac death, major adverse cardiac event (MACE), major adverse cardiac (and cerebral) event (MACCE), and repeat revascularization at 10 years of Group-A was 60 ± 5%, 67 ± 5%, 48 ± 5%, 37 ± 5%, and 81 ± 4%, respectively, compared with 58 ± 5%, 70 ± 5%, 49 ± 5%, 39 ± 5%, and 93 ± 3% in Group-V. There were no significant differences in these end points between groups regardless of insulin-dependency. Multivariable Cox proportional hazards model identified age, left ventricular ejection fraction, renal failure, and hyperlipidemia as independent predictors for all death, age and left ventricular ejection fraction for cardiac death, sinus rhythm for both MACE and MACCE, and prior percutaneous coronary intervention for re-revascularization.  In our experience, complete arterial revascularization using LITA/RA "T-Grafts" does not provide superior long-term clinical benefits for diabetic patients compared with a combination of LITA and sequential vein graft. Georg Thieme Verlag KG Stuttgart · New York.

Errors in radial velocity variance from Doppler wind lidar

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, H.; Barthelmie, R. J.; Doubrawa, P.

A high-fidelity lidar turbulence measurement technique relies on accurate estimates of radial velocity variance that are subject to both systematic and random errors determined by the autocorrelation function of radial velocity, the sampling rate, and the sampling duration. Our paper quantifies the effect of the volumetric averaging in lidar radial velocity measurements on the autocorrelation function and the dependence of the systematic and random errors on the sampling duration, using both statistically simulated and observed data. For current-generation scanning lidars and sampling durations of about 30 min and longer, during which the stationarity assumption is valid for atmospheric flows, themore » systematic error is negligible but the random error exceeds about 10%.« less

Errors in radial velocity variance from Doppler wind lidar

DOE PAGES

Wang, H.; Barthelmie, R. J.; Doubrawa, P.; ...

2016-08-29

A high-fidelity lidar turbulence measurement technique relies on accurate estimates of radial velocity variance that are subject to both systematic and random errors determined by the autocorrelation function of radial velocity, the sampling rate, and the sampling duration. Our paper quantifies the effect of the volumetric averaging in lidar radial velocity measurements on the autocorrelation function and the dependence of the systematic and random errors on the sampling duration, using both statistically simulated and observed data. For current-generation scanning lidars and sampling durations of about 30 min and longer, during which the stationarity assumption is valid for atmospheric flows, themore » systematic error is negligible but the random error exceeds about 10%.« less

Comparison of vascular distensibility in the upper and lower extremity.

PubMed

Eiken, O; Kölegård, R

2004-07-01

Because of the great differences in hydrostatic pressure acting along the blood vessels in the erect posture, leg vessels are exposed to greater transmural pressures than arm vessels. The in vivo pressure-distension relationship of arteries, arterioles and veins in the arm were compared with those of the leg. Experiments were performed with the subject (n = 11) positioned in a pressure chamber with an arm or lower leg (test limb) extended at heart level through a hole in the chamber door. Intravascular pressure in the arm/lower leg was increased by stepwise increasing chamber pressure to +180 and +210 mmHg, respectively. Diameters of blood vessels and arterial flow were measured using ultrasonographic/Doppler techniques. Changes in forearm and lower leg volumes were assessed using an impedance technique. The subject rated perceived pain in the test limb. The brachial and radial arteries were found to be more distensible than the posterior tibial artery (P < 0.001). Likewise, the distension was more pronounced in the cephalic than in the great saphenous vein (P < 0.001). In the brachial artery, but not in the posterior tibial artery, flow increased markedly at the highest levels of distending pressure (P < 0.001). At the highest intravascular pressures, the rate of change in tissue impedance was greater in the forearm than the lower leg (P < 0.01). At any given level of markedly increased pressure, pain was rated higher in the arm than in the leg (P < 0.001). It seems that the wall stiffness of arteries, pre-capillary resistance vessels and veins adapts to meet the long-term demands imposed by the hydrostatic pressure acting locally on the vessel walls.

Carotid rupture following electrical injury: a report of two cases.

PubMed

Toy, Jonathan; Ball, Brandon J; Tredget, Edward E

2012-01-01

Electrical injuries often result in extensive tissue damage where vascular damage may occur and result in thrombosis and spontaneous rupture of blood vessels. Rupture of the brachial, radial, ulnar, internal mammary, and obturator arteries has been reported in the literature. The authors present two cases of carotid artery rupture following high-voltage electrical injuries. The first case is a 21-year-old man who was climbing a fence near a high-voltage power line when a gold chain he was wearing around his neck caught on the power line, resulting in a 10% circumferential electrical injury to his neck. He presented with visible arterial bleeding from the large neck wound and was taken to the operating room, where a 1-cm laceration to the carotid artery was repaired with a vein patch. On the second postoperative day, the patch dislodged, and a spontaneous rupture of the common carotid artery occurred. The damaged artery was subsequently ligated. The patient recovered with no neurological sequelae. The second case is a 43-year-old man who suffered a high-voltage injury while working on an electrical panel, resulting in a 50% TBSA full-thickness burn to the face, scalp, trunk, and extremities. Four weeks after admission, a latissimus dorsi myocutaneous free flap was used for coverage of exposed outer table of the skull. Intraoperatively, the carotid artery spontaneously ruptured proximal to where the dissection was being carried out. The patient recovered with no neurological sequelae. High-voltage electrical injury results in significant damage to blood vessels via a number of mechanisms. Rupture of a major vessel is a rare, life-threatening sequelae of electrical injury.

Results of Early High-Flow Bypass and Trapping for Ruptured Blood Blister-Like Aneurysms of the Internal Carotid Artery.

PubMed

Kikkawa, Yuichiro; Ikeda, Toshiki; Takeda, Ririko; Nakajima, Hiroyuki; Ogura, Takeshi; Ooigawa, Hidetoshi; Kurita, Hiroki

2017-09-01

The aim of this study is to clarify the efficacy and safety of early surgery using trapping of the affected internal carotid artery (ICA) and high-flow bypass between the second portion of the middle cerebral artery and cervical external carotid artery with radial artery graft for ruptured blood blister-like aneurysms (BBAs) arising from the anterior wall of the ICA. Medical charts of 16 consecutive patients (7 men and 9 women; mean, 59 years) with subarachnoid hemorrhage (World Federation of Neurosurgical Societies grade I, n = 2; grade II, n = 5; grade III, n = 2; grade IV, n = 4; grade V, n = 3) caused by ruptured BBA surgically treated between July 2010 and October 2015 were retrospectively reviewed. Eleven patients underwent acute surgery within 24 hours after the onset, whereas surgery was performed between 3 and 17 days after the onset because of referral delay or associated vasospasm in 5 patients. All patients underwent the same surgical procedure. Elimination of the BBA and patency of the bypass were achieved in all patients. Postoperatively, 2 patients showed small infarction in the Heubner artery area, and 2 others suffered symptomatic vasospasm, but no patient suffered infarction in the posterior communicating/anterior choroidal artery territories. Identically, no patient showed ischemic optic neuropathy. At the last follow-up (mean, 36 months), favorable clinical outcome (good recovery or mild disability in Glasgow Outcome Scale) was achieved in 14 (88%) of the patients without rebleeding or refilling of the aneurysms. Early surgical repair of BBAs by trapping of the affected ICA with high-flow bypass is safe and effective treatment with satisfactory midterm outcome. Copyright © 2017 Elsevier Inc. All rights reserved.

Effect of CPAP on arterial stiffness in severely obese patients with obstructive sleep apnoea.

PubMed

Seetho, Ian W; Asher, Rebecca; Parker, Robert J; Craig, Sonya; Duffy, Nick; Hardy, Kevin J; Wilding, John P H

2015-12-01

Obstructive sleep apnoea (OSA) may independently increase cardiovascular risk in obesity. Although there is evidence that arterial stiffness is altered in OSA, knowledge of these effects with continuous positive airway pressure (CPAP) in severe obesity (body mass index (BMI) ≥ 35 kg/m(2)) is limited. This study aimed to explore how arterial stiffness, as measured by the augmentation index (Aix), changed in severely obese patients with OSA who were treated with CPAP and in patients without OSA. Forty-two patients with severe obesity-22 with OSA, 20 without OSA-were recruited at baseline and followed-up after a median of 13.5 months. Pulse wave analysis (PWA) was performed using applanation tonometry at the radial artery to measure augmentation index (Aix), augmentation pressure (AP) and subendocardial viability ratio (SEVR). Cardiovascular parameters and body composition were also measured. There were significant improvements in Aix, AP (both P < 0.001) and SEVR (P = 0.021) in OSA patients on CPAP compared with subjects without OSA. Epworth scores (P < 0.001), systolic (P < 0.001) and mean arterial pressures (P = 0.002) improved with CPAP. Regression showed that CPAP was significantly associated with change in arterial stiffness from baseline. However, patients with OSA on CPAP continued to have increased arterial stiffness (Aix) (P < 0.001), AP (P = 0.028) and reduced SEVR (P = 0.002) relative to non-OSA patients. Although sleepiness and blood pressure improve with CPAP in severe obesity, CPAP alone is not sufficient to modify PWA measures to levels comparable with non-OSA patients. This supports a need for a multifaceted approach when managing cardiovascular risk in patients with severe obesity and obstructive sleep apnoea receiving CPAP therapy.

In vivo observation of the hypo-echoic "black hole" phenomenon in rat arterial bloodstream: a preliminary Study.

PubMed

Nam, Kweon-Ho; Paeng, Dong-Guk

2014-07-01

The "black hole," a hypo-echoic hole at the center of the bloodstream surrounded by a hyper-echoic zone in cross-sectional views, has been observed in ultrasound backscattering measurements of blood with red blood cell aggregation in in vitro studies. We investigated whether the phenomenon occurs in the in vivo arterial bloodstream of rats using a high-frequency ultrasound imaging system. Longitudinal and cross-sectional ultrasound images of the rat common carotid artery (CCA) and abdominal aorta were obtained using a 40-MHz ultrasound system. A high-frame-rate retrospective imaging mode was employed to precisely examine the dynamic changes in blood echogenicity in the arteries. When the imaging was performed with non-invasive scanning, blood echogenicity was very low in the CCA as compared with the surrounding tissues, exhibiting no hypo-echoic zone at the center of the vessel. Invasive imaging of the CCA by incising the skin and subcutaneous tissues at the imaging area provided clearer and brighter blood echo images, showing the "black hole" phenomenon near the center of the vessel in longitudinal view. The "black hole" was also observed in the abdominal aorta under direct imaging after laparotomy. The aortic "black hole" was clearly observed in both longitudinal and cross-sectional views. Although the "black hole" was always observed near the center of the arteries during the diastolic phase, it dissipated or was off-center along with the asymmetric arterial wall dilation at systole. In conclusion, we report the first in vivo observation of the hypo-echoic "black hole" caused by the radial variation of red blood cell aggregation in arterial bloodstream. Copyright © 2014 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

Isolated Human Pulmonary Artery Structure and Function Pre- and Post-Cardiopulmonary Bypass Surgery.

PubMed

Dora, Kim A; Stanley, Christopher P; Al Jaaly, Emad; Fiorentino, Francesca; Ascione, Raimondo; Reeves, Barnaby C; Angelini, Gianni D

2016-02-23

Pulmonary dysfunction is a known complication after cardiac surgery using cardiopulmonary bypass, ranging from subclinical functional changes to prolonged postoperative ventilation, acute lung injury, and acute respiratory distress syndrome. Whether human pulmonary arterial function is compromised is unknown. The aim of the present study was to compare the structure and function of isolated and cannulated human pulmonary arteries obtained from lung biopsies after the chest was opened (pre-cardiopulmonary bypass) to those obtained at the end of cardiopulmonary bypass (post-cardiopulmonary bypass) from patients undergoing coronary artery bypass graft surgery. Pre- and post-cardiopulmonary bypass lung biopsies were received from 12 patients undergoing elective surgery. Intralobular small arteries were dissected, cannulated, pressurized, and imaged using confocal microscopy. Functionally, the thromboxane mimetic U46619 produced concentration-dependent vasoconstriction in 100% and 75% of pre- and post-cardiopulmonary bypass arteries, respectively. The endothelium-dependent agonist bradykinin stimulated vasodilation in 45% and 33% of arteries pre- and post-cardiopulmonary bypass, respectively. Structurally, in most arteries smooth muscle cells aligned circumferentially; live cell viability revealed that although 100% of smooth muscle and 90% of endothelial cells from pre-cardiopulmonary bypass biopsies had intact membranes and were considered viable, only 60% and 58%, respectively, were viable from post-cardiopulmonary bypass biopsies. We successfully investigated isolated pulmonary artery structure and function in fresh lung biopsies from patients undergoing heart surgery. Pulmonary artery contractile tone and endothelium-dependent dilation were significantly reduced in post-cardiopulmonary bypass biopsies. The decreased functional responses were associated with reduced cell viability. URL: http://www.isrctn.com/ISRCTN34428459. Unique identifier: ISRCTN 34428459. © 2016 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

A Meshless Method Using Radial Basis Functions for Beam Bending Problems

NASA Technical Reports Server (NTRS)

Raju, I. S.; Phillips, D. R.; Krishnamurthy, T.

2004-01-01

A meshless local Petrov-Galerkin (MLPG) method that uses radial basis functions (RBFs) as trial functions in the study of Euler-Bernoulli beam problems is presented. RBFs, rather than generalized moving least squares (GMLS) interpolations, are used to develop the trial functions. This choice yields a computationally simpler method as fewer matrix inversions and multiplications are required than when GMLS interpolations are used. Test functions are chosen as simple weight functions as they are in the conventional MLPG method. Compactly and noncompactly supported RBFs are considered. Noncompactly supported cubic RBFs are found to be preferable. Patch tests, mixed boundary value problems, and problems with complex loading conditions are considered. Results obtained from the radial basis MLPG method are either of comparable or better accuracy than those obtained when using the conventional MLPG method.

Sector magnets or transverse electromagnetic fields in cylindrical coordinates

DOE PAGES

Zolkin, T.

2017-04-10

Laplace’s equation is considered for scalar and vector potentials describing electric or magnetic fields in cylindrical coordinates, with invariance along the azimuthal coordinate. In a series, we found special functions which, when expanded to lowest order in power series in radial and vertical coordinates, replicate harmonic polynomials in two variables. These functions are based on radial harmonics found by Edwin M. McMillan forty years ago. In addition to McMillan’s harmonics, a second family of radial harmonics is introduced to provide a symmetric description between electric and magnetic fields and to describe fields and potentials in terms of the same functions.more » Formulas are provided which relate any transverse fields specified by the coefficients in the power series expansion in radial or vertical planes in cylindrical coordinates with the set of new functions. Our result is important for potential theory and for theoretical study, design and proper modeling of sector dipoles, combined function dipoles and any general sector element for accelerator physics. All results are presented in connection with these problems.« less

Sector magnets or transverse electromagnetic fields in cylindrical coordinates

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zolkin, T.

Laplace’s equation is considered for scalar and vector potentials describing electric or magnetic fields in cylindrical coordinates, with invariance along the azimuthal coordinate. In a series, we found special functions which, when expanded to lowest order in power series in radial and vertical coordinates, replicate harmonic polynomials in two variables. These functions are based on radial harmonics found by Edwin M. McMillan forty years ago. In addition to McMillan’s harmonics, a second family of radial harmonics is introduced to provide a symmetric description between electric and magnetic fields and to describe fields and potentials in terms of the same functions.more » Formulas are provided which relate any transverse fields specified by the coefficients in the power series expansion in radial or vertical planes in cylindrical coordinates with the set of new functions. Our result is important for potential theory and for theoretical study, design and proper modeling of sector dipoles, combined function dipoles and any general sector element for accelerator physics. All results are presented in connection with these problems.« less

Flow-mediated vasodilation is augmented in a corkscrew collateral artery compared with that in a native artery in patients with thromboangiitis obliterans (Buerger disease).

PubMed

Fujii, Yuichi; Fujimura, Noritaka; Mikami, Shinsuke; Maruhashi, Tatsuya; Kihara, Yasuki; Chayama, Kazuaki; Noma, Kensuke; Higashi, Yukihito

2011-12-01

A healthy endothelium maintains vascular tone and structure. The purpose of this study was to evaluate endothelial function in corkscrew collateral arteries in Buerger disease. We measured flow-mediated vasodilation (FMD) in corkscrew arteries in 26 patients with Buerger disease, in control arteries in 26 healthy subjects, and in native arteries in 16 patients with Buerger disease. Hyperemic flow was lower in corkscrew arteries than in native arteries in patients with Buerger disease and in control arteries in healthy subjects. There was no significant difference between hyperemic flow in patients with Buerger disease in whom measurements were performed in native arteries and that in healthy subjects. FMD was lower in corkscrew arteries and native arteries in patients with Buerger disease than in control arteries in healthy subjects. There was no significant difference between FMD in corkscrew arteries in patients with Buerger disease and in that in native arteries. The ratio of FMD to hyperemic flow was significantly smaller in native arteries in patients with Buerger disease than in corkscrew arteries and in control arteries in healthy subjects (5.5 ± 6.2 vs 8.8 ± 8.9 and 9.6 ± 7.6 mL/min, P < .001, respectively). There was no significant difference in the ratio of FMD to hyperemic flow between corkscrew arteries in Buerger disease and control arteries in healthy subjects. Nitroglycerin-induced vasodilation was similar in all leg arteries. Endothelial function of a corkscrew collateral artery in patients with Buerger disease is maintained, while endothelial function is impaired in a native artery in Buerger disease. Copyright © 2011 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.

Relation between digital peripheral arterial tonometry and brachial artery ultrasound measures of vascular function in patients with coronary artery disease and in healthy volunteers.

PubMed

Lee, Craig R; Bass, Almasa; Ellis, Kyle; Tran, Bryant; Steele, Savanna; Caughey, Melissa; Stouffer, George A; Hinderliter, Alan L

2012-03-01

Digital peripheral arterial tonometry (PAT) is an emerging, noninvasive method to assess vascular function. The physiology underlying this phenotype, however, remains unclear. Therefore, we evaluated the relation between digital PAT and established brachial artery ultrasound measures of vascular function under basal conditions and after reactive hyperemia. Using a cross-sectional study design, digital PAT and brachial artery ultrasonography with pulsed wave Doppler were simultaneously completed at baseline and after reactive hyperemia in both those with established coronary artery disease (n = 99) and healthy volunteers with low cardiovascular disease risk (n = 40). Under basal conditions, the digital pulse volume amplitude demonstrated a significant positive correlation with the brachial artery velocity-time integral that was independent of the arterial diameter, in both the healthy volunteer (r(s) = 0.64, p <0.001) and coronary artery disease (r(s) = 0.63, p <0.001) cohorts. Similar positive relations were observed with the baseline brachial artery blood flow velocity and blood flow. In contrast, no relation between the reactive hyperemia-evoked digital PAT ratio and either brachial artery flow-mediated dilation or shear stress was observed in either cohort (p = NS). In conclusion, these findings demonstrate that the digital PAT measures of vascular function more closely reflect basal blood flow in the brachial artery than reactive hyperemia-induced changes in the arterial diameter or flow velocity, and the presence of vascular disease does not modify the physiology underlying the digital PAT phenotype. Copyright © 2012 Elsevier Inc. All rights reserved.

Design and Performance Evaluation of Real-time Endovascular Interventional Surgical Robotic System with High Accuracy.

PubMed

Wang, Kundong; Chen, Bing; Lu, Qingsheng; Li, Hongbing; Liu, Manhua; Shen, Yu; Xu, Zhuoyan

2018-05-15

Endovascular interventional surgery (EIS) is performed under a high radiation environment at the sacrifice of surgeons' health. This paper introduces a novel endovascular interventional surgical robot that aims to reduce radiation to surgeons and physical stress imposed by lead aprons during fluoroscopic X-ray guided catheter intervention. The unique mechanical structure allowed the surgeon to manipulate the axial and radial motion of the catheter and guide wire. Four catheter manipulators (to manipulate the catheter and guide wire), and a control console which consists of four joysticks, several buttons and two twist switches (to control the catheter manipulators) were presented. The entire robotic system was established on a master-slave control structure through CAN (Controller Area Network) bus communication, meanwhile, the slave side of this robotic system showed highly accurate control over velocity and displacement with PID controlling method. The robotic system was tested and passed in vitro and animal experiments. Through functionality evaluation, the manipulators were able to complete interventional surgical motion both independently and cooperatively. The robotic surgery was performed successfully in an adult female pig and demonstrated the feasibility of superior mesenteric and common iliac artery stent implantation. The entire robotic system met the clinical requirements of EIS. The results show that the system has the ability to imitate the movements of surgeons and to accomplish the axial and radial motions with consistency and high-accuracy. Copyright © 2018 John Wiley & Sons, Ltd.

POLYANA-A tool for the calculation of molecular radial distribution functions based on Molecular Dynamics trajectories

NASA Astrophysics Data System (ADS)

Dimitroulis, Christos; Raptis, Theophanes; Raptis, Vasilios

2015-12-01

We present an application for the calculation of radial distribution functions for molecular centres of mass, based on trajectories generated by molecular simulation methods (Molecular Dynamics, Monte Carlo). When designing this application, the emphasis was placed on ease of use as well as ease of further development. In its current version, the program can read trajectories generated by the well-known DL_POLY package, but it can be easily extended to handle other formats. It is also very easy to 'hack' the program so it can compute intermolecular radial distribution functions for groups of interaction sites rather than whole molecules.

Improved radial dose function estimation using current version MCNP Monte-Carlo simulation: Model 6711 and ISC3500 125I brachytherapy sources.

PubMed

Duggan, Dennis M

2004-12-01

Improved cross-sections in a new version of the Monte-Carlo N-particle (MCNP) code may eliminate discrepancies between radial dose functions (as defined by American Association of Physicists in Medicine Task Group 43) derived from Monte-Carlo simulations of low-energy photon-emitting brachytherapy sources and those from measurements on the same sources with thermoluminescent dosimeters. This is demonstrated for two 125I brachytherapy seed models, the Implant Sciences Model ISC3500 (I-Plant) and the Amersham Health Model 6711, by simulating their radial dose functions with two versions of MCNP, 4c2 and 5.

Rheumatoid Arthritis is Independently Associated with Increased Left Ventricular Mass but not Reduced Ejection Fraction

PubMed Central

Rudominer, Rebecca L.; Roman, Mary J.; Devereux, Richard B.; Paget, Stephen A.; Schwartz, Joseph E.; Lockshin, Michael D.; Crow, Mary K.; Sammaritano, Lisa; Levine, Daniel M.; Salmon, Jane E.

2008-01-01

Background Rheumatoid arthritis (RA) is a chronic inflammatory disease associated with premature atherosclerosis, vascular stiffening, and heart failure. Whether RA is associated with underlying structural and functional abnormalities of the left ventricle (LV) is poorly understood. Methods and Results 89 patients with RA without clinical cardiovascular disease and 89 healthy matched controls underwent echocardiography, carotid ultrasonography, and radial tonometry to measure arterial stiffness. RA patients and controls were similar in body size, hypertension and diabetes status, and cholesterol. LV diastolic diameter (4.92 vs. 4.64 cm, p <0.001), mass (136.9 vs. 121.7 g, p = 0.001 or 36.5 vs. 32.9 g/m 2.7, p = 0.01), ejection fraction (EF) (71% vs. 67%, p <0.001), and prevalence of LV hypertrophy (LVH) (18% vs. 6.7%, p = 0.023) were all higher among RA patients. In multivariate analysis, presence of RA (p = 0.004) was an independent correlate of LV mass. Furthermore, RA was independently associated with the presence of LVH (OR 4.14, [95% CI 1.24-13.80; p=0.021]). Among RA patients, age at diagnosis and disease duration were independently related to LV mass. RA patients with LVH were older and had higher systolic pressure, damage index score, C-reactive protein, homocysteine and arterial stiffness index compared to those without LVH. Conclusion RA is associated with increased LV mass. Disease duration is independently related to increased LV mass, suggesting a pathophysiological link between chronic inflammation and LVH. In contrast, LV systolic function is preserved in RA patients indicating that systolic dysfunction is not an intrinsic feature of RA. PMID:19116901

Myocardial Deformation Measured by 3-Dimensional Speckle Tracking in Children and Adolescents With Systemic Arterial Hypertension.

PubMed

Navarini, Susanne; Bellsham-Revell, Hannah; Chubb, Henry; Gu, Haotian; Sinha, Manish D; Simpson, John M

2017-12-01

Systemic arterial hypertension predisposes children to cardiovascular risk in childhood and adult life. Despite extensive study of left ventricular (LV) hypertrophy, detailed 3-dimensional strain analysis of cardiac function in hypertensive children has not been reported. The aim of this study was to evaluate LV mechanics (strain, twist, and torsion) in young patients with hypertension compared with a healthy control group and assess factors associated with functional measurements. Sixty-three patients (26 hypertension and 37 normotensive) were enrolled (mean age, 14.3 and 11.4 years; 54% men and 41% men, respectively). All children underwent clinical evaluation and echocardiographic examination, including 3-dimensional strain. There was no difference in LV volumes and ejection fraction between the groups. Myocardial deformation was significantly reduced in those with hypertension compared with controls. For hypertensive and normotensive groups, respectively, global longitudinal strain was -15.1±2.3 versus -18.5±1.9 ( P <0.0001), global circumferential strain -15.2±3 versus -19.9±3.1 (<0.0001), global radial strain +44.0±11.3 versus 63.4±10.5 ( P <0.0001), and global 3-dimensional strain -26.1±3.8 versus -31.5±3.8 ( P <0.0001). Basal clockwise rotation, apical counterclockwise rotation, twist, and torsion were not significantly different. After multivariate regression analyses blood pressure, body mass index and LV mass maintained a significant relationship with measures of LV strain. Similar ventricular volumes and ejection fraction were observed in hypertensive and normotensive children, but children with hypertension had significantly lower strain indices. Whether reduced strain might predict future cardiovascular risk merits further longitudinal study. © 2017 American Heart Association, Inc.

GuideLiner™ as guide catheter extension for the unreachable mammary bypass graft.

PubMed

Vishnevsky, Alec; Savage, Michael P; Fischman, David L

2018-03-09

Percutaneous coronary intervention (PCI) of mammary artery bypass grafts through a trans-radial (TR) approach can present unique challenges, including coaxial vessel engagement of the guiding catheter, adequate visualization of the target lesion, sufficient backup support for equipment delivery, and the ability to reach very distal lesions. The GuideLiner catheter, a rapid exchange monorail mother-in-daughter system, facilitates successful interventions in such challenging anatomy. We present a case of a patient undergoing PCI of a right internal mammary artery (RIMA) graft via TR access in whom the graft could not be engaged with any guiding catheter. Using a balloon tracking technique over a guidewire, a GuideLiner was placed as an extension of the guiding catheter and facilitated TR-PCI by overcoming technical challenges associated with difficult anatomy. © 2018 Wiley Periodicals, Inc.

Behaviour of two typical stents towards a new stent evolution.

PubMed

Simão, M; Ferreira, J M; Mora-Rodriguez, J; Fragata, J; Ramos, H M

2017-06-01

This study explores the analysis of a new stent geometry from two typical stents used to treat the coronary artery disease. Two different finite element methods are applied with different boundary conditions to investigate the stenosis region. Computational fluid dynamics (CFD) models including fluid-structure interaction are used to assess the haemodynamic impact of two types of coronary stents implantation: (1) type 1-based on a strut-link stent geometry and (2) type 2-a continuous helical stent. Using data from a recent clinical stenosis, flow disturbances and consequent shear stress alterations introduced by the stent treatment are investigated. A relationship between stenosis and the induced flow fields for the two types of stent designs is analysed as well as the correlation between haemodynamics and vessel wall biomechanical factors during the initiation and development of stenosis formation in the coronary artery. Both stents exhibit a good performance in reducing the obstruction artery. However, stent type 1 presents higher radial deformation than the type 2. This deformation can be seen as a limitation with a long-term clinical impact.

Adaptive control with self-tuning for non-invasive beat-by-beat blood pressure measurement.

PubMed

Nogawa, Masamichi; Ogawa, Mitsuhiro; Yamakoshi, Takehiro; Tanaka, Shinobu; Yamakoshi, Ken-ichi

2011-01-01

Up to now, we have successfully carried out the non-invasive beat-by-beat measurement of blood pressure (BP) in the root of finger, superficial temporal and radial artery based on the volume-compensation technique with reasonable accuracy. The present study concerns with improvement of control method for this beat-by-beat BP measurement. The measurement system mainly consists of a partial pressurization cuff with a pair of LED and photo-diode for the detection of arterial blood volume, and a digital self-tuning control method. Using healthy subjects, the performance and accuracy of this system were evaluated through comparison experiments with the system using a conventional empirically tuned PID controller. The significant differences of BP measured in finger artery were not showed in systolic (SBP), p=0.52, and diastolic BP (DBP), p=0.35. With the advantage of the adaptive control with self-tuning method, which can tune the control parameters without disturbing the control system, the application area of the non-invasive beat-by-beat measurement method will be broadened.

Effect of fat loss on arterial elasticity in obese adolescents with clinical insulin resistance: RESIST study.

PubMed

Ho, Mandy; Gow, Megan; Baur, Louise A; Benitez-Aguirre, Paul Z; Tam, Charmaine S; Donaghue, Kim C; Craig, Maria E; Cowell, Chris T; Garnett, Sarah P

2014-10-01

Reduced arterial elasticity contributes to an obesity-related increase in cardiovascular risk in adults. To evaluate the effect of fat loss on arterial elasticity in obese adolescents at risk of type 2 diabetes. A secondary data analysis of the RESIST study was performed in two hospitals in Sydney, Australia. The study included 56 subjects (ages, 10 to 17 y; 25 males) with prediabetes and/or clinical features of insulin resistance. A 12-month lifestyle plus metformin intervention. Arterial elasticity and systemic vascular resistance were measured using radial tonometry pulse contour analysis, percentage body fat (%BF) was measured by dual-energy x-ray absorptiometry, and insulin sensitivity index was derived from an oral glucose tolerance test and lipids. Adolescents (n = 31) with decreased %BF (mean change [range], -4.4% [-18.3 to -0.01%]) after the intervention had significant increases in the mean large arterial elasticity index (mean change [95%CI], 5.1 [1.9 to 8.2] mL/mm Hg * 10; P = .003) and insulin sensitivity index (0.5 [0.1 to 0.9]; P = .010) and a decrease in systemic vascular resistance (-82 [-129 to -35] dyne * s * cm(-5); P = .001). There were no significant changes in these parameters in adolescents who increased their %BF. Nor was there any significant change in the mean small arterial elasticity index in either group. Long-term follow-up of these adolescents is warranted to assess whether the observed changes in vascular elasticity will lead to a clinical benefit including reduced cardiovascular morbidity and mortality.

Relationship between glycaemic levels and arterial stiffness in non-diabetic adults.

PubMed

Cavero-Redondo, Iván; Martínez-Vizcaíno, Vicente; Álvarez-Bueno, Celia; Recio-Rodríguez, José Ignacio; Gómez-Marcos, Manuel Ángel; García-Ortiz, Luis

2018-01-23

To examine, in a non-diabetic population, whether the association between arterial stiffness and glycaemic levels depends on the test used as a glycaemic indicator, fasting plasma glucose (FPG) or glycated haemoglobin A1c (HbA1c). A cross-sectional analysis of a 220 non-diabetic subsample from the EVIDENT II study in which FPG, HbA1c and arterial stiffness-related parameters (pulse wave velocity, radial and central augmentation index, and central pulse pressure) were determined. Mean differences in arterial stiffness-related parameters by HbA1c and FPG tertiles were tested using analysis of covariance. All means of arterial stiffness-related parameters increased by HbA1c tertiles, although mean differences were only statistically significant in pulse wave velocity (p ≤.001), even after controlling for potential confounders (HbA1c <5.30% = 6.88 m/s; HbA1c 5.30%-5.59% = 7.06 m/s; and HbA1c ≥5.60% = 8.16 m/s, p =.004). Conversely, mean differences in pulse wave velocity by FPG tertiles did not reach statistically significant differences after controlling for potential confounders (FPG 4.44 mmol/l = 7.18 m/s; FPG 4.44 mmol/l-4.87 mmol/l = 7.26 m/s; and FPG ≥4.88 mmol/l = 7.93 m/s, p =.066). Glucose levels in a non-diabetic population were associated with arterial stiffness but better when levels were determined using HbA1c. Copyright © 2017 Elsevier España, S.L.U. All rights reserved.

Effect of quantum dispersion on the radial distribution function of a one-component sticky-hard-sphere fluid

NASA Astrophysics Data System (ADS)

Fantoni, Riccardo

2018-04-01

In this short communication we present a possible scheme to study the radial distribution function of the quantum slightly polydisperse Baxter sticky hard sphere liquid at finite temperature thorugh a semi-analytical method devised by Chandler and Wolynes.

Radial Basis Function Based Quadrature over Smooth Surfaces

DTIC Science & Technology

2016-03-24

Radial Basis Functions φ(r) Piecewise Smooth (Conditionally Positive Definite) MN Monomial |r|2m+1 TPS thin plate spline |r|2mln|r| Infinitely Smooth...smooth surfaces using polynomial interpolants, while [27] couples Thin - Plate Spline interpolation (see table 1) with Green’s integral formula [29

Effects of bileaflet mechanical heart valve orientation on coronary flow

NASA Astrophysics Data System (ADS)

Haya, Laura; Tavoularis, Stavros

2015-11-01

The aortic sinus is approximately tri-radially symmetric, but bileaflet mechanical heart valves (BMHVs), which are commonly used to replace diseased aortic valves, are bilaterally symmetric. This mismatch in symmetry suggests that the orientation in which a BMHV is implanted within the aortic sinus affects the flow characteristics downstream of it. This study examines the effect of BMHV orientation on the flow in the coronary arteries, which originate in the aortic sinus and supply the heart tissue with blood. Planar particle image velocimetry measurements were made past a BMHV mounted at the inlet of an anatomical aorta model under physiological flow conditions. The complex interactions between the valve jets, the sinus vortex and the flow in the right coronary artery were elucidated for three valve orientations. The coronary flow rate was directly affected by the size, orientation, and time evolution of the vortex in the sinus, all of which were sensitive to the valve's orientation. The total flow through the artery was highest when the valve was oriented with its axis of symmetry intersecting the artery's opening. The findings of this research may assist surgeons in choosing the best orientation for BMHV implantation. The bileaflet valve was donated by St. Jude Medical. Financial support was provided by the Natural Sciences and Engineering Research Council of Canada.

Amyloid-β efflux from the CNS into the plasma

PubMed Central

Roberts, Kaleigh Filisa; Elbert, Donald L.; Kasten, Tom P.; Patterson, Bruce W.; Sigurdson, Wendy C.; Connors, Rose E.; Ovod, Vitaliy; Munsell, Ling Y.; Mawuenyega, Kwasi G.; Miller-Thomas, Michelle M.; Moran, Christopher J.; Cross, Dewitte T.; Derdeyn, Colin P.; Bateman, Randall J.

2015-01-01

Objective The aim of this study was to measure the flux of amyloid-β (Aβ) across the human cerebral capillary bed in order to determine if transport into the blood is a significant mechanism of clearance for Aβ produced in the central nervous system (CNS). Methods Time-matched blood samples were simultaneously collected from a cerebral vein (including the sigmoid sinus, inferior petrosal sinus, and the internal jugular vein), femoral vein, and radial artery of patients undergoing Inferior Petrosal Sinus Sampling (IPSS). For each plasma sample, Aβ concentration was assessed by three assays and the venous to arterial Aβ concentration ratios were determined. Results Aβ concentration was increased by ~7.5% in venous blood leaving the CNS capillary bed compared to arterial blood, indicating efflux from the CNS into the peripheral blood (p < 0.0001). There was no difference in peripheral venous Aβ concentration compared to arterial blood concentration. Interpretation Our results are consistent with clearance of CNS-derived Aβ into the venous blood supply with no increase from a peripheral capillary bed. Modeling these results suggests that direct transport of Aβ across the blood-brain barrier accounts for ~25% of Aβ clearance, and reabsorption of cerebrospinal fluid Aβ accounts for ~25% of the total CNS Aβ clearance in humans. PMID:25205593

Dual-modality arterial pulse monitoring system for continuous blood pressure measurement.

PubMed

Wen-Xuan Dai; Yuan-Ting Zhang; Jing Liu; Xiao-Rong Ding; Ni Zhao

2016-08-01

Accurate and ambulatory measurement of blood pressure (BP) is essential for efficient diagnosis, management and prevention of cardiovascular diseases (CVDs). However, traditional cuff-based BP measurement methods provide only intermittent BP readings and can cause discomfort with the occlusive cuff. Although pulse transit time (PTT) method is promising for cuffless and continuous BP measurement, its pervasive use is restricted by its limited accuracy and requirement of placing sensors on multiple body sites. To tackle these issues, we propose a novel dual-modality arterial pulse monitoring system for continuous blood pressure measurement, which simultaneously records the pressure and photoplethysmography (PPG) signals of radial artery. The obtained signals can be used to generate a pressure-volume curve, from which the elasticity index (EI) and viscosity index (VI) can be extracted. Experiments were carried out among 7 healthy subjects with their PPG, ECG, arterial pressure wave and reference BP collected to examine the effectiveness of the proposed indexes. The results of this study demonstrate that a linear regression model combining EI and VI has significantly higher BP tracking correlation coefficient as compared to the PTT method. This suggests that the proposed system and method can potentially be used for convenient and continuous blood pressure estimation with higher accuracy.

A simple on-line arterial time-activity curve detector for [O-15] water PET studies

NASA Astrophysics Data System (ADS)

Wollenweber, S. D.; Hichwa, R. D.; Ponto, L. L. B.

1997-08-01

A simple, automated on-line detector system has been fabricated and implemented to detect the arterial time-activity curve (TAG) for bolus-injection [O-15] water PET studies. This system offers two significant improvements over existing systems: a pump mechanism is not required to control arterial blood flow through the detector and dispersion correction of the time-activity curve for dispersion in external tubing is unnecessary. The [O-15] positrons emanating from blood within a thin-walled, 0.134 cm inner-diameter plastic tube are detected by a 0.5 cm wide by 1.0 cm long by 0.1 cm thick plastic scintillator mounted to a miniature PMT. Photon background is reduced to insignificant levels by a 2.0 cm thick cylindrical lead shield. Mean cerebral blood flow (mCBF) determined from an autoradiographic model and from the TAC measured by 1-second automated sampling was compared to that calculated from a TAC acquired using 5-second integrated manual samples. Improvements in timing resolution (1-sec vs. 5-sec) cause small but significant differences between the two sampling methods. Dispersion is minimized due to small tubing diameters, short lengths of tubing between the radial arterial sampling site and the detector and the presence of a 3-way valve 10 cm proximal to the detector.

Multiplicity of morphologies in poly (l-lactide) bioresorbable vascular scaffolds

PubMed Central

Ailianou, Artemis; Ramachandran, Karthik; Kossuth, Mary Beth; Oberhauser, James Paul; Kornfield, Julia A.

2016-01-01

Poly(l-lactide) (PLLA) is the structural material of the first clinically approved bioresorbable vascular scaffold (BVS), a promising alternative to permanent metal stents for treatment of coronary heart disease. BVSs are transient implants that support the occluded artery for 6 mo and are completely resorbed in 2 y. Clinical trials of BVSs report restoration of arterial vasomotion and elimination of serious complications such as late stent thrombosis. It is remarkable that a scaffold made from PLLA, known as a brittle polymer, does not fracture when crimped onto a balloon catheter or during deployment in the artery. We used X-ray microdiffraction to discover how PLLA acquired ductile character and found that the crimping process creates localized regions of extreme anisotropy; PLLA chains in the scaffold change orientation from the hoop direction to the radial direction on micrometer-scale distances. This multiplicity of morphologies in the crimped scaffold works in tandem to enable a low-stress response during deployment, which avoids fracture of the PLLA hoops and leaves them with the strength needed to support the artery. Thus, the transformations of the semicrystalline PLLA microstructure during crimping explain the unexpected strength and ductility of the current BVS and point the way to thinner resorbable scaffolds in the future. PMID:27671659

Analytical bound-state solutions of the Schrödinger equation for the Manning-Rosen plus Hulthén potential within SUSY quantum mechanics

NASA Astrophysics Data System (ADS)

Ahmadov, A. I.; Naeem, Maria; Qocayeva, M. V.; Tarverdiyeva, V. A.

2018-01-01

In this paper, the bound-state solution of the modified radial Schrödinger equation is obtained for the Manning-Rosen plus Hulthén potential by using new developed scheme to overcome the centrifugal part. The energy eigenvalues and corresponding radial wave functions are defined for any l≠0 angular momentum case via the Nikiforov-Uvarov (NU) and supersymmetric quantum mechanics (SUSY QM) methods. Thanks to both methods, equivalent expressions are obtained for the energy eigenvalues, and the expression of radial wave functions transformations to each other is presented. The energy levels and the corresponding normalized eigenfunctions are represented in terms of the Jacobi polynomials for arbitrary l states. A closed form of the normalization constant of the wave functions is also found. It is shown that, the energy eigenvalues and eigenfunctions are sensitive to nr radial and l orbital quantum numbers.

Neurogenic Radial Glia-like Cells in Meninges Migrate and Differentiate into Functionally Integrated Neurons in the Neonatal Cortex.

PubMed

Bifari, Francesco; Decimo, Ilaria; Pino, Annachiara; Llorens-Bobadilla, Enric; Zhao, Sheng; Lange, Christian; Panuccio, Gabriella; Boeckx, Bram; Thienpont, Bernard; Vinckier, Stefan; Wyns, Sabine; Bouché, Ann; Lambrechts, Diether; Giugliano, Michele; Dewerchin, Mieke; Martin-Villalba, Ana; Carmeliet, Peter

2017-03-02

Whether new neurons are added in the postnatal cerebral cortex is still debated. Here, we report that the meninges of perinatal mice contain a population of neurogenic progenitors formed during embryonic development that migrate to the caudal cortex and differentiate into Satb2 + neurons in cortical layers II-IV. The resulting neurons are electrically functional and integrated into local microcircuits. Single-cell RNA sequencing identified meningeal cells with distinct transcriptome signatures characteristic of (1) neurogenic radial glia-like cells (resembling neural stem cells in the SVZ), (2) neuronal cells, and (3) a cell type with an intermediate phenotype, possibly representing radial glia-like meningeal cells differentiating to neuronal cells. Thus, we have identified a pool of embryonically derived radial glia-like cells present in the meninges that migrate and differentiate into functional neurons in the neonatal cerebral cortex. Copyright © 2016 Elsevier Inc. All rights reserved.

Noninvasive assessment of arterial function in children: clinical applications

PubMed Central

Aggoun, Y; Beghetti, M

2002-01-01

Non invasive methods to assess arterial function are widely used in adults. The development and progression of arterial vascular disease is a multifactorial process that can start early in life, thus even in a pediatric population. Risk factors for cardiovascular disease mediate their effects by altering the structure, properties and function of wall and endothelial components of the arterial blood vessels. The ability to detect and monitor sub-clinical damage, representing the cumulative and integrated influence of risk factors in impairing arterial wall integrity, holds potential to further refine cardiovascular risk stratification and enable early intervention to prevent or attenuate disease progression. Measurements that provide more direct information in relation to changes in arterial wall integrity clearly hold predictive and therapeutic potential. The aim of this current review will be to describe the non-invasive procedure used in children to investigate the mechanical properties of a great elastic artery, the common carotid, and the endothelial function of the brachial artery. The accuracy of recording noninvasively the blood pressure wave contour along the arterial tree has been improved by the technique of applanation tonometry. The results obtained with these methods in previous studies are described. PMID:22368620

Arterial stiffness and decline of renal function in a primary care population.

PubMed

van Varik, Bernard J; Vossen, Liv M; Rennenberg, Roger J; Stoffers, Henri E; Kessels, Alfons G; de Leeuw, Peter W; Kroon, Abraham A

2017-01-01

Arterial stiffness is an important pathophysiological factor linking cardiovascular disease and kidney disease. Controversy exists as to whether arterial stiffness causes renal function decline, or kidney dysfunction leads to stiffening or whether the association is mutual. We aimed to investigate the longitudinal association between arterial stiffness and annual rate of renal function decline. We prospectively investigated in a primary care population whether carotid-femoral pulse wave velocity (PWV) was associated with estimated glomerular filtration rate (eGFR) and annual decline in eGFR in participants aged ⩾40 years without overt kidney disease. Baseline data on PWV and eGFR were available for 587 participants; follow-up measurements with a mean duration of 5.6 years were available for 222 patients. PWV, female gender and mean arterial pressure were independently associated with eGFR at baseline, although age confounded this association. More importantly, baseline PWV, age and eGFR were independent predictors of renal function decline. Stratification for age showed that the effect of PWV on rate of eGFR decline was amplified with advancing age. On the other hand, baseline eGFR did not determine annual change in PWV, suggesting a unidirectional association between arterial stiffness and eGFR. Arterial stiffness amplifies age-related renal function decline, suggesting that arterial stiffness plays a causal role in the development of renal damage, at least at later stages of age-related renal function decline, possibly through impaired renal autoregulation and increased arterial blood pressure pulsatility.

Psychophysiological Studies II. Performance and Physiological Response in Coronary Prone and Noncoronary Prone Individuals.

DTIC Science & Technology

1986-01-30

Cyborg BL907 heart rate monitor. A pressure sensitive transducer was placed over the radial artery of the left arm to measure HR in beats per minute...measurement was obtained with a Cyborg Thermal P642. Temperature was recorded by a thermistor placed on the dorsal surface of the middle finger of...the left hand (second phalanx) and was displayed to .01 degrees Farenheit. Electromyogram activity was measured with a Cyborg P303. Measurements (to .1

Obesity and overweight associated with increased carotid diameter and decreased arterial function in young otherwise healthy men.

PubMed

Kappus, Rebecca M; Fahs, Christopher A; Smith, Denise; Horn, Gavin P; Agiovlasitis, Stomatis; Rossow, Lindy; Jae, Sae Y; Heffernan, Kevin S; Fernhall, Bo

2014-04-01

Obesity is linked to cardiovascular disease, stroke, increased mortality and vascular remodeling. Although increased arterial diameter is associated with multiple cardiovascular risk factors and obesity, it is unknown whether lumen enlargement is accompanied by unfavorable vascular changes in young and otherwise healthy obese individuals. The purpose of this study was to compare carotid and brachial artery diameter, blood pressure, arterial stiffness, and endothelial function in young, apparently healthy, normal-weight, overweight, and obese male subjects. One hundred sixty-five male subjects (27.39±0.59 years) were divided into 3 groups (normal weight, overweight, and obese) according to body mass index. Subjects underwent cardiovascular measurements to determine arterial diameter, function, and stiffness. After adjusting for age, the obese group had significantly greater brachial, carotid, and aortic pressures, brachial pulse wave velocity, carotid intima media thickness, and carotid arterial diameter compared with both the overweight and normal-weight groups. Obesity is associated with a much worse arterial profile, as an increased carotid lumen size was accompanied by higher blood pressure, greater arterial stiffness, and greater carotid intima media thickness in obese compared with overweight or normal-weight individuals. These data suggest that although obesity may be a factor in arterial remodeling, such remodeling is also accompanied by other hemodynamic and arterial changes consistent with reduced arterial function and increased cardiovascular risk.

Obesity and Overweight Associated With Increased Carotid Diameter and Decreased Arterial Function in Young Otherwise Healthy Men

PubMed Central

2014-01-01

BACKGROUND Obesity is linked to cardiovascular disease, stroke, increased mortality and vascular remodeling. Although increased arterial diameter is associated with multiple cardiovascular risk factors and obesity, it is unknown whether lumen enlargement is accompanied by unfavorable vascular changes in young and otherwise healthy obese individuals. The purpose of this study was to compare carotid and brachial artery diameter, blood pressure, arterial stiffness, and endothelial function in young, apparently healthy, normal-weight, overweight, and obese male subjects. METHODS One hundred sixty-five male subjects (27.39±0.59 years) were divided into 3 groups (normal weight, overweight, and obese) according to body mass index. Subjects underwent cardiovascular measurements to determine arterial diameter, function, and stiffness. RESULTS After adjusting for age, the obese group had significantly greater brachial, carotid, and aortic pressures, brachial pulse wave velocity, carotid intima media thickness, and carotid arterial diameter compared with both the overweight and normal-weight groups. CONCLUSIONS Obesity is associated with a much worse arterial profile, as an increased carotid lumen size was accompanied by higher blood pressure, greater arterial stiffness, and greater carotid intima media thickness in obese compared with overweight or normal-weight individuals. These data suggest that although obesity may be a factor in arterial remodeling, such remodeling is also accompanied by other hemodynamic and arterial changes consistent with reduced arterial function and increased cardiovascular risk. PMID:24048148

Prediction of Left Ventricular Filling Pressure by 3-Dimensional Speckle-Tracking Echocardiography in Patients With Coronary Artery Disease.

PubMed

Ma, Hong; Xie, Rong-Ai; Gao, Li-Jian; Zhang, Jin-Ping; Wu, Wei-Chun; Wang, Hao

2015-10-01

The purpose of this study was to investigate the diagnostic value of 3-dimensional (3D) speckle-tracking echocardiography for estimating left ventricular filling pressure in patients with coronary artery disease (CAD) and a preserved left ventricular ejection fraction. Altogether, 84 patients with CAD and 30 age- and sex-matched healthy control participants in sinus rhythm were recruited prospectively. All participants underwent conventional and 3D speckle-tracking echocardiography. Global strain values were automatically calculated by 3D speckle-tracking analysis. The left ventricular end-diastolic pressure (LVEDP) was determined invasively by left heart catheterization. Echocardiography and cardiac catheterization were performed within 24 hours. Compared with the controls, patients with CAD showed lower global longitudinal strain, global circumferential strain, global area strain, and global radial strain. Patients with CAD who had an elevated LVEDP had much lower levels of all 4 3D-speckle-tracking echocardiographic variables. Pearson correlation analysis revealed that the LVEDP correlated positively with the early transmitral flow velocity/early diastolic myocardial velocity (E/E') ratio, global longitudinal strain, global circumferential strain, and global area strain. It correlated negatively with global radial strain. Receiver operating characteristic curve analysis revealed that these 3D speckle-tracking echocardiographic indices could effectively predict elevated left ventricular filling pressure (LVEDP >15 mm Hg) in patients with CAD (areas under the curve: global longitudinal strain, 0.78; global radial strain, 0.77; global circumferential strain, 0.75; and global area strain, 0.74). These parameters, however, showed no advantages over the commonly used E/E' ratio (area under the curve, 0.84). Three-dimensional speckle-tracking echocardiography was a practical technique for predicting elevated left ventricular filling pressure, but it might not be superior to the commonly used E/E' ratio in patients with CAD who have a normal left ventricular ejection fraction. © 2015 by the American Institute of Ultrasound in Medicine.

Transradial percutaneous coronary intervention without on-site cardiac surgery for stable coronary disease and myocardial infarction: preliminary report and initial experience in 174 patients.

PubMed

Escárcega, Ricardo O; Pérez-Alva, Juan C; Jiménez-Hernández, Mario; Mendoza-Pinto, Claudia; Pérez, Ruben S; Porras, Renán S; García-Carrasco, Mario

2010-10-01

On-site cardiac surgery is not widely available in developing countries despite a high prevalence of coronary artery disease. To analyze the safety, feasibility and cost-effectiveness of transradial percutaneous coronary intervention without on-site cardiac surgery in a community hospital in a developing country. Of the 174 patients who underwent PCI for the first time in our center, we analyzed two groups: stable coronary disease and acute myocardial infarction. The primary endpoint was the rate of complications during the first 24 hours after PCI. We also analyzed the length of hospital stay and the rate of hospital readmission in the first week after PCI, and compared costs between the radial and femoral approaches. The study group comprised 131 patients with stable coronary disease and 43 with acute MI. Among the patients with stable coronary disease 8 (6.1%) had pulse loss, 12 (9.16%) had on-site hematoma, and 3 (2.29%) had bleeding at the site of the puncture. Among the patients with acute MI, 3 (6.98) had pulse loss and 5 (11.63%) had bleeding at the site of the puncture. There were no cases of atriovenous fistula or nerve damage. In the stable coronary disease group, 130 patients (99%) were discharged on the same day (2.4 +/- 2 hours). In the acute MI group, the length of stay was 6.6 +/- 2.5 days with at least 24 hours in the intensive care unit. There were no hospital readmissions in the first week after the procedure. The total cost, which includes equipment related to the specific approach and recovery room stay, was significantly lower with the radial approach compared to the femoral approach (US$ 500 saving per intervention). The transradial approach was safe and feasible in a community hospital in a developing country without on-site cardiac surgery backup. The radial artery approach is clearly more cost-effective than the femoral approach.

Clinical Results and Mechanical Properties of the Carotid CGUARD Double-Layered Embolic Prevention Stent.

PubMed

Wissgott, Christian; Schmidt, Wolfram; Brandt-Wunderlich, Christoph; Behrens, Peter; Andresen, Reimer

2017-02-01

To report early clinical outcomes with a novel double-layer stent for the internal carotid artery (ICA) and the in vitro investigation of the stent's mechanical properties. A prospective single-center study enrolled 30 consecutive patients (mean age 73.1±6.3 years; 21 men) with symptomatic (n=25) or high-grade (n=5) ICA stenosis treated with the new double-layer carotid CGUARD Embolic Prevention System (EPS) stent, which has an inner open-cell nitinol design with an outer closed-cell polyethylene terephthalate layer. The average stenosis of the treated arteries was 84.1%±7.9% with a mean lesion length of 16.6±2.1 mm. In the laboratory, 8×40-mm stents where tested in vitro with respect to their radial force during expansion, the bending stiffness of the stent system and the expanded stent, as well as the collapse pressure in a thin and flexible sheath. The wall adaptation was assessed using fluoroscopy after stent release in step and curved vessel models. The stent was successfully implanted in all patients. No peri- or postprocedural complications occurred; no minor or major stroke was observed in the 6-month follow-up. The bending stiffness of the expanded stent was 63.1 N·mm 2 and (not unexpectedly) was clearly lower than that of the stent system (601.5 N·mm 2 ). The normalized radial force during expansion of the stent to 7.0 mm, consistent with in vivo sizing, was relatively high (0.056 N/mm), which correlates well with the collapse pressure of 0.17 bars. Vessel wall adaptation was harmonic and caused no straightening of the vessel after clinical application. Because of its structure, the novel CGUARD EPS stent is characterized by a high flexibility combined with a high radial force and very good plaque coverage. These first clinical results demonstrate a very safe implantation behavior without any stroke up to 6 months after the procedure.

[The biological reaction of inflammation, methylglyoxal of blood plasma, functional and structural alterations in elastic type arteries at the early stage of hypertension disease].

PubMed

Titov, V N; Dmitriev, V A; Oshchepkov, E V; Balakhonova, T V; Tripoten', M I; Shiriaeva, Iu K

2012-08-01

The article deals with studying of the relationship between biologic reaction of inflammation with glycosylation reaction and content of methylglyoxal in blood serum. The positive correlation between pulse wave velocity and content of methylglyoxal, C-reactive protein in intercellular medium and malleolar brachial index value was established. This data matches the experimental results concerning involvement of biological reaction of inflammation into structural changes of elastic type arteries under hypertension disease, formation of arteries' rigidity and increase of pulse wave velocity. The arterial blood pressure is a biological reaction of hydrodynamic pressure which is used in vivo by several biological functions: biological function of homeostasis, function of endoecology, biological function of adaptation and function of locomotion. The biological reaction of hydrodynamic (hydraulic) pressure is a mode of compensation of derangement of several biological functions which results in the very high rate of hypertension disease in population. As a matter of fact, hypertension disease is a syndrome of lingering pathological compensation by higher arterial blood pressure of the biological functions derangements occurring in the distal section at the level of paracrine cenoses of cells. The arterial blood pressure is a kind of in vivo integral indicator of deranged metabolism. The essential hypertension disease pathogenically is a result of the derangement of three biological functions: biological function of homeostasis, biological function of trophology - nutrition (biological reaction of external feeding - exotrophia) and biological function of endoecology. In case of "littering" of intercellular medium in vivo with nonspecific endogenic flogogens a phylogenetically earlier activation of biological reactions of excretion, inflammation and hydrodynamic arterial blood pressure occur. In case of derangement of biological function of homeostasis, decreasing of perfusion even in single paracrine cenoses and derangement of biological function of endoecology ("purity" of intercellular medium) the only response always will be the increase of arterial blood pressure.

Angiographic predictors of 3-year patency of bypass grafts implanted on the right coronary artery system: a prospective randomized comparison of gastroepiploic artery, saphenous vein, and right internal thoracic artery grafts.

PubMed

Glineur, David; D'hoore, William; de Kerchove, Laurent; Noirhomme, Philippe; Price, Joel; Hanet, Claude; El Khoury, Gebrine

2011-11-01

Saphenous vein, in situ right gastroepiploic artery, and right internal thoracic artery grafts are routinely used to revascularize the right coronary artery. Little is known about the predictive value of objective preoperative angiographic parameters on midterm graft patency. We prospectively enrolled 210 consecutive patients undergoing coronary revascularization. Revascularization of the right coronary artery was randomly performed with the saphenous vein grafts in 81 patients and the right gastroepiploic artery in 92 patients. During the same study period, 37 patients received right coronary artery revascularization with the right internal thoracic artery used in a Y-composite fashion. All patients underwent a protocol-driven coronary angiogram 3 years after surgery. Preoperative angiographic parameters included minimum lumen diameter percent stenosis measured by quantitative angiography. A graft was considered "not functional" with patency scores of 0 to 2 and "functional" with patency scores of 3 or 4. Angiographic follow-up was 100% complete. A significant difference in the distribution of flow patterns was observed in the 3 groups. In multivariate analysis, the use of a saphenous vein graft was associated with superior graft functionality compared with the other conduits (odds ratio, 6.1; 95% confidence interval, 2.4-15). Graft function was negatively influenced by the minimum lumen diameter (odds ratio, 0.11; confidence interval, 0.05-0.25). In the right gastroepiploic artery and right internal thoracic artery groups, the proportion of functional grafts was higher when the minimum lumen diameter was below a threshold value in the third minimum lumen diameter quartile (0.64-1.30 mm). Preoperative angiography predicts graft patency in the right gastroepiploic artery and right internal thoracic artery, whereas the flow pattern in saphenous vein grafts is significantly less influenced by quantitative angiographic parameters. Copyright © 2011 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.

Geometric Alteration of Renal Arteries After Fenestrated Grafting and the Impact on Renal Function.

PubMed

Ou, Jiale; Chan, Yiu-Che; Chan, Crystal Yin-Tung; Cheng, Stephen W K

2017-05-01

This study aims to investigate the degree of geometric change on renal arteries and its impact on renal function after fenestrated endovascular aortic repair (fEVAR). Twenty-five patients with fEVAR were included. There were 47 renal arteries target vessels, and 43 of these (22 left and 21 right vessels) stented successfully. Their preoperative and first postoperative follow-up computed tomography (CT) images were reconstructed using the Aquarius workstation (TeraRecon, San Mateo, CA, USA). The superior mesenteric artery (SMA) or celiac axis (if SMA was stented) was appointed as reference origin. The longitudinal orientation of a renal artery or a stent was represented by a takeoff angle (ToA) between the renal artery or stent and the distal abdominal aorta. The postoperative stent ToAs were compared with those of preoperative renal arteries. Preoperative and short-term postoperative serum creatinine levels were measured. Renal function impairment was indicated as a >30% or >2.0 mg/dL rise in serum creatinine compared to the preoperative level. The relationship between postoperative renal function impairment and the stent orientation or geometric changes in renal arteries was correlated. The patency rate of renal arteries was 100% at the first postoperative CT review. The average ToAs of both renal arteries were significantly enlarged after stenting (P < 0.05). Seven stent deformations (16.3%) in four patients (16.0%) were observed. They were attributed to caudal misalignment of the fenestrated stent graft (n = 6) or inaccurate graft sizing (n = 1). There was no stent fracture or target vessel loss. Postoperatively, nine patients (36.0%) at day 1 and 10 patients (41.7%) after 3 months suffered the renal function impairment. This was found not to be associated with the stent angulation or angular change of the renal arteries (both P > 0.05). The three patients with stent deformation due to misalignment suffered postoperative renal function impairment and continuing deterioration in renal function. Implanted renal stents could angulate renal arteries more cephalad after fenestrated stenting. Postoperative renal function impairment was not associated with the stent orientation and changes in vessel orientation. Accurate fenestrated alignment is important to maintain stent performance and preserve renal function. Copyright © 2017 Elsevier Inc. All rights reserved.

Note: Precise radial distribution of charged particles in a magnetic guiding field

DOE Office of Scientific and Technical Information (OSTI.GOV)

Backe, H., E-mail: backe@kph.uni-mainz.de

2015-07-15

Current high precision beta decay experiments of polarized neutrons, employing magnetic guiding fields in combination with position sensitive and energy dispersive detectors, resulted in a detailed study of the mono-energetic point spread function (PSF) for a homogeneous magnetic field. A PSF describes the radial probability distribution of mono-energetic electrons at the detector plane emitted from a point-like source. With regard to accuracy considerations, unwanted singularities occur as a function of the radial detector coordinate which have recently been investigated by subdividing the radial coordinate into small bins or employing analytical approximations. In this note, a series expansion of the PSFmore » is presented which can numerically be evaluated with arbitrary precision.« less

Notch3 is required for arterial identity and maturation of vascular smooth muscle cells

PubMed Central

Domenga, Valérie; Fardoux, Peggy; Lacombe, Pierre; Monet, Marie; Maciazek, Jacqueline; Krebs, Luke T.; Klonjkowski, Bernard; Berrou, Eliane; Mericskay, Matthias; Li, Zhen; Tournier-Lasserve, Elisabeth; Gridley, Thomas; Joutel, Anne

2004-01-01

Formation of a fully functional artery proceeds through a multistep process. Here we show that Notch3 is required to generate functional arteries in mice by regulating arterial differentiation and maturation of vascular smooth muscle cells (vSMC). In adult Notch3–/– mice distal arteries exhibit structural defects and arterial myogenic responses are defective. The postnatal maturation stage of vSMC is deficient in Notch3–/– mice. We further show that Notch3 is required for arterial specification of vSMC but not of endothelial cells. Our data reveal Notch3 to be the first cell-autonomous regulator of arterial differentiation and maturation of vSMC. PMID:15545631

Arterial stiffness and wave reflection: sex differences and relationship with left ventricular diastolic function.

PubMed

Russo, Cesare; Jin, Zhezhen; Palmieri, Vittorio; Homma, Shunichi; Rundek, Tatjana; Elkind, Mitchell S V; Sacco, Ralph L; Di Tullio, Marco R

2012-08-01

Increased arterial stiffness and wave reflection have been reported in heart failure with normal ejection fraction (HFNEF) and in asymptomatic left ventricular (LV) diastolic dysfunction, a precursor of HFNEF. It is unclear whether women, who have higher frequency of HFNEF, are more vulnerable than men to the deleterious effects of arterial stiffness on LV diastolic function. We investigated, in a large community-based cohort, whether sex differences exist in the relationship among arterial stiffness, wave reflection, and LV diastolic function. Arterial stiffness and wave reflection were assessed in 983 participants from the Cardiovascular Abnormalities and Brain Lesions study using applanation tonometry. The central pulse pressure/stroke volume index, total arterial compliance, pulse pressure amplification, and augmentation index were used as parameters of arterial stiffness and wave reflection. LV diastolic function was evaluated by 2-dimensional echocardiography and tissue-Doppler imaging. Arterial stiffness and wave reflection were greater in women compared with men, independent of body size and heart rate (all P<0.01), and showed inverse relationships with parameters of diastolic function in both sexes. Further adjustment for cardiovascular risk factors attenuated these relationships; however, a higher central pulse pressure/stroke volume index predicted LV diastolic dysfunction in women (odds ratio, 1.54; 95% confidence intervals, 1.03 to 2.30) and men (odds ratio, 2.09; 95% confidence interval, 1.30 to 3.39), independent of other risk factors. In conclusion, in our community-based cohort study, higher arterial stiffness was associated with worse LV diastolic function in men and women. Women's higher arterial stiffness, independent of body size, may contribute to their greater susceptibility to develop HFNEF.

Dominance of free wall radial motion in global right ventricular function of heart transplant recipients.

PubMed

Lakatos, Bálint Károly; Tokodi, Márton; Assabiny, Alexandra; Tősér, Zoltán; Kosztin, Annamária; Doronina, Alexandra; Rácz, Kristóf; Koritsánszky, Kinga Bianka; Berzsenyi, Viktor; Németh, Endre; Sax, Balázs; Kovács, Attila; Merkely, Béla

2018-03-01

Assessment of right ventricular (RV) function using conventional echocardiography might be inadequate as the radial motion of the RV free wall is often neglected. Our aim was to quantify the longitudinal and the radial components of RV function using three-dimensional (3D) echocardiography in heart transplant (HTX) recipients. Fifty-one HTX patients in stable cardiovascular condition without history of relevant rejection episode or chronic allograft vasculopathy and 30 healthy volunteers were enrolled. RV end-diastolic (EDV) volume and total ejection fraction (TEF) were measured by 3D echocardiography. Furthermore, we quantified longitudinal (LEF) and radial ejection fraction (REF) by decomposing the motion of the RV using the ReVISION method. RV EDV did not differ between groups (HTX vs control; 96 ± 27 vs 97 ± 2 mL). In HTX patients, TEF was lower, however, tricuspid annular plane systolic excursion (TAPSE) decreased to a greater extent (TEF: 47 ± 7 vs 54 ± 4% [-13%], TAPSE: 11 ± 5 vs 21 ± 4 mm [-48%], P < .0001). In HTX patients, REF/TEF ratio was significantly higher compared to LEF/TEF (REF/TEF vs LEF/TEF: 0.58 ± 0.10 vs 0.27 ± 0.08, P < .0001), while in controls the REF/TEF and LEF/TEF ratio was similar (0.45 ± 0.07 vs 0.47 ± 0.07). Current results confirm the superiority of radial motion in determining RV function in HTX patients. Parameters incorporating the radial motion are recommended to assess RV function in HTX recipients. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Effects of Acupuncture Stimulation on the Radial artery’s Pressure Pulse Wave in Healthy Young Participants: Protocol for a prospective, single-Arm, Exploratory, Clinical Study

PubMed Central

Shin, Jae-Young; Lee, Jun-Hwan; Ku, Boncho; Bae, Jang Han; un, Min-Ho; Kim, Jaeuk U.; Kim, Tae-Hun

2016-01-01

Introduction: This study aims to investigate the effects of acupuncture stimulation on the radial artery’s pressure pulse wave, along with various hemodynamic parameters, and to explore the possible underlying mechanism of pulse diagnosis in healthy participants in their twenties. Methods and analysis: This study is a prospective, single-arm, exploratory clinical study. A total of 25 healthy participants, without regard to gender, in their twenties will be recruited by physicians. Written informed consent will be obtained from all participants. The participants will receive acupuncture once at ST36 on both sides. The radial arterial pulse waves will be measured on the left arm of the subjects by using an applicable pulse tonometric device (KIOM-PAS). On the right arm (appearing twice), electrocardiogram (ECG), photoplethysmogram (PPG), respiration and cardiac output (CO) signals, will be measured using a physiological data acquisition system (Biopac module), while the velocity of blood flow, and the diameter and the depth of the blood vessel will be measured using an ultrasonogram machine on the right arm (appearing twice). All measurements will be conducted before, during, and after acupuncture. The primary outcome will be the spectral energy at high frequencies above 10 Hz (SE10-30Hz) calculated from the KIOM-PAS device signal. Secondary outcomes will be various variables obtained from the KIOM-PAS device, ECG, PPG, impedance cardiography modules, and an ultrasonogram machine. Discussion: The results of this trial will provide information regarding the physiological and the hemodynamic mechanisms underlying acupuncture stimulation and clinical evidence for the influence of acupuncture on the pressure pulse wave in the radial artery. Ethics and dissemination: This study was approved by the Institutional Review Board (IRB) of Kyung Hee University’s Oriental Medical Center, Seoul, Korea (KOMCIRB-150818-HR-030). The study findings will be published in peer-reviewed journals and presented at national and international conferences. Trial registration number: This trial was registered with the Clinical Research Information Service (CRIS) at the Korea National Institute of Health (NIH), Republic of Korea (KCT0001663), which is a registry in the World Health Organization’s (WHO’s) Registry Network. PMID:27695628

Clinical performance of a free-breathing spatiotemporally accelerated 3-D time-resolved contrast-enhanced pediatric abdominal MR angiography.

PubMed

Zhang, Tao; Yousaf, Ufra; Hsiao, Albert; Cheng, Joseph Y; Alley, Marcus T; Lustig, Michael; Pauly, John M; Vasanawala, Shreyas S

2015-10-01

Pediatric contrast-enhanced MR angiography is often limited by respiration, other patient motion and compromised spatiotemporal resolution. To determine the reliability of a free-breathing spatiotemporally accelerated 3-D time-resolved contrast-enhanced MR angiography method for depicting abdominal arterial anatomy in young children. With IRB approval and informed consent, we retrospectively identified 27 consecutive children (16 males and 11 females; mean age: 3.8 years, range: 14 days to 8.4 years) referred for contrast-enhanced MR angiography at our institution, who had undergone free-breathing spatiotemporally accelerated time-resolved contrast-enhanced MR angiography studies. A radio-frequency-spoiled gradient echo sequence with Cartesian variable density k-space sampling and radial view ordering, intrinsic motion navigation and intermittent fat suppression was developed. Images were reconstructed with soft-gated parallel imaging locally low-rank method to achieve both motion correction and high spatiotemporal resolution. Quality of delineation of 13 abdominal arteries in the reconstructed images was assessed independently by two radiologists on a five-point scale. Ninety-five percent confidence intervals of the proportion of diagnostically adequate cases were calculated. Interobserver agreements were also analyzed. Eleven out of 13 arteries achieved acceptable image quality (mean score range: 3.9-5.0) for both readers. Fair to substantial interobserver agreement was reached on nine arteries. Free-breathing spatiotemporally accelerated 3-D time-resolved contrast-enhanced MR angiography frequently yields diagnostic image quality for most abdominal arteries in young children.

Routine intraoperative completion angiography after coronary artery bypass grafting and 1-stop hybrid revascularization results from a fully integrated hybrid catheterization laboratory/operating room.

PubMed

Zhao, David X; Leacche, Marzia; Balaguer, Jorge M; Boudoulas, Konstantinos D; Damp, Julie A; Greelish, James P; Byrne, John G; Ahmad, Rashid M; Ball, Stephen K; Cleator, John H; Deegan, Robert J; Eagle, Susan S; Fong, Pete P; Fredi, Joseph L; Hoff, Steven J; Jennings, Henry S; McPherson, John A; Piana, Robert N; Pretorius, Mias; Robbins, Mark A; Slosky, David A; Thompson, Annemarie

2009-01-20

This study sought to report our experience with a routine completion angiogram after coronary artery bypass surgery (CABG) and simultaneous (1-stop) percutaneous coronary intervention (PCI) at the time of CABG performed in the hybrid catheterization laboratory/operating room. The value of a routine completion angiogram after CABG and 1-stop hybrid CABG/PCI remains unresolved. Between April 2005 and July 2007, 366 consecutive patients underwent CABG surgery, with (n = 112) or without (n = 254) concomitant 1-stop PCI (hybrid), all with completion angiography before chest closure. Among the 112 1-stop hybrid CABG/PCI patients, 67 (60%) underwent a planned hybrid procedure based on pre-operative assessment, whereas 45 (40%) underwent open-chest PCI (unplanned hybrid) based on intraoperative findings. Among the 796 CABG grafts (345 left internal mammary artery, 12 right internal mammary artery/radial, and 439 veins), 97 (12%) angiographic defects were identified. Defects were repaired with either a minor adjustment of the graft (n = 22, 2.8%), with intraoperative open-chest PCI (unplanned hybrid, n = 48, 6%) or with traditional surgical revision (n = 27, 3.4%). Hybrid patients had clinical outcomes similar to standard CABG patients. Routine completion angiography detected 12% of grafts with important angiographic defects. One-stop hybrid coronary revascularization is reasonable, safe, and feasible. Combining the tools of the catheterization laboratory and operating room greatly enhances the options available to the surgeon and cardiologist for patients with complex coronary artery disease.

A note on the radial solutions for the supercritical Hénon equation

NASA Astrophysics Data System (ADS)

Barutello, Vivina; Secchi, Simone; Serra, Enrico

2008-05-01

We prove the existence of a positive radial solution for the Hénon equation with arbitrary growth. The solution is found by means of a shooting method and turns out to be an increasing function of the radial variable. Some numerical experiments suggest the existence of many positive oscillating solutions.

Tire-rim interface pressure of a commercial vehicle wheel under radial loads: theory and experiment

NASA Astrophysics Data System (ADS)

Wan, Xiaofei; Shan, Yingchun; Liu, Xiandong; He, Tian; Wang, Jiegong

2017-11-01

The simulation of the radial fatigue test of a wheel has been a necessary tool to improve the design of the wheel and calculate its fatigue life. The simulation model, including the strong nonlinearity of the tire structure and material, may produce accurate results, but often leads to a divergence in calculation. Thus, a simplified simulation model in which the complicated tire model is replaced with a tire-wheel contact pressure model is used extensively in the industry. In this paper, a simplified tire-rim interface pressure model of a wheel under a radial load is established, and the pressure of the wheel under different radial loads is tested. The tire-rim contact behavior affected by the radial load is studied and analyzed according to the test result, and the tire-rim interface pressure extracted from the test result is used to evaluate the simplified pressure model and the traditional cosine function model. The results show that the proposed model may provide a more accurate prediction of the wheel radial fatigue life than the traditional cosine function model.

Curcumin supplementation improves vascular endothelial function in healthy middle-aged and older adults by increasing nitric oxide bioavailability and reducing oxidative stress.

PubMed

Santos-Parker, Jessica R; Strahler, Talia R; Bassett, Candace J; Bispham, Nina Z; Chonchol, Michel B; Seals, Douglas R

2017-01-03

We hypothesized that curcumin would improve resistance and conduit artery endothelial function and large elastic artery stiffness in healthy middle-aged and older adults. Thirty-nine healthy men and postmenopausal women (45-74 yrs) were randomized to 12 weeks of curcumin (2000 mg/day Longvida®; n=20) or placebo (n=19) supplementation. Forearm blood flow response to acetylcholine infusions (FBF ACh ; resistance artery endothelial function) increased 37% following curcumin supplementation (107±13 vs. 84±11 AUC at baseline, P=0.03), but not placebo (P=0.2). Curcumin treatment augmented the acute reduction in FBF ACh induced by the nitric oxide synthase inhibitor NG monomethyl-L-arginine (L-NMMA; P=0.03), and reduced the acute increase in FBF ACh to the antioxidant vitamin C (P=0.02), whereas placebo had no effect (both P>0.6). Similarly, brachial artery flow-mediated dilation (conduit artery endothelial function) increased 36% in the curcumin group (5.7±0.4 vs. 4.4±0.4% at baseline, P=0.001), with no change in placebo (P=0.1). Neither curcumin nor placebo influenced large elastic artery stiffness (aortic pulse wave velocity or carotid artery compliance) or circulating biomarkers of oxidative stress and inflammation (all P>0.1). In healthy middle-aged and older adults, 12 weeks of curcumin supplementation improves resistance artery endothelial function by increasing vascular nitric oxide bioavailability and reducing oxidative stress, while also improving conduit artery endothelial function.

Curcumin supplementation improves vascular endothelial function in healthy middle-aged and older adults by increasing nitric oxide bioavailability and reducing oxidative stress

PubMed Central

Santos-Parker, Jessica R.; Strahler, Talia R.; Bassett, Candace J.; Bispham, Nina Z.; Chonchol, Michel B.; Seals, Douglas R.

2017-01-01

We hypothesized that curcumin would improve resistance and conduit artery endothelial function and large elastic artery stiffness in healthy middle-aged and older adults. Thirty-nine healthy men and postmenopausal women (45-74 yrs) were randomized to 12 weeks of curcumin (2000 mg/day Longvida®; n=20) or placebo (n=19) supplementation. Forearm blood flow response to acetylcholine infusions (FBFACh; resistance artery endothelial function) increased 37% following curcumin supplementation (107±13 vs. 84±11 AUC at baseline, P=0.03), but not placebo (P=0.2). Curcumin treatment augmented the acute reduction in FBFACh induced by the nitric oxide synthase inhibitor NG monomethyl-L-arginine (L-NMMA; P=0.03), and reduced the acute increase in FBFACh to the antioxidant vitamin C (P=0.02), whereas placebo had no effect (both P>0.6). Similarly, brachial artery flow-mediated dilation (conduit artery endothelial function) increased 36% in the curcumin group (5.7±0.4 vs. 4.4±0.4% at baseline, P=0.001), with no change in placebo (P=0.1). Neither curcumin nor placebo influenced large elastic artery stiffness (aortic pulse wave velocity or carotid artery compliance) or circulating biomarkers of oxidative stress and inflammation (all P>0.1). In healthy middle-aged and older adults, 12 weeks of curcumin supplementation improves resistance artery endothelial function by increasing vascular nitric oxide bioavailability and reducing oxidative stress, while also improving conduit artery endothelial function. PMID:28070018

[Clinical observation on the different treatments targeted at different types of radial head fracture and radial neck fracture].

PubMed

Zhang, Ying-Ze; Guo, Ming-Ke; Zheng, Zhan-le; Zhang, Qi; Chen, Wei

2009-06-15

To assess the effect of the different treatments targeted at different types of radial head fracture and radial neck fracture. A retrospective study was performed in 87 patients from February 2006 to March 2007. Fifty-four patients with radial head fractures included 36 males and 18 females, aged from 18 to 65 years (the average age was 33); Forty of them resulted from crashing, 8 from traffic injury and 6 from falling injury. According to Mason classification system, there were 15 type I, 23 type II and 16 type III. Thirty-three patients with radial neck fractures included 21 males and 12 females, aged from 9 to 17 years (the average age was 13), 29 of them resulted from crashing, 1 from traffic injury and 3 from falling injury. According to O'Brien classification system, there were 8 type I, 14 type II and 11 type III. Type I of radial head fractures and radial neck fractures were immobilization with cast, the patients with type II of radial head fractures were treated with open reduction and micro-screw or T-trapezoid and bridge-shaped plate fixation and type III had operations to fix with bridge-shaped locked plate and repair the broken annular ligament, or replace heads with prosthesis. All patients with type II and type III of radial neck fractures were treated with closed reduction by leverage and percutaneous intra-medullary nailing. The patients were followed up for 4-12 months (mean 7.2 months). The functional recovery degrees were evaluated with Wheeler's evaluation system. In group of radial head fractures, the results were excellent in 26 patients, good in 20, fair in 6 and poor in 2, the excellent and good rate was 85.2%. In group of radial neck fractures, the results were excellent in 20 patients, good in 9, fair in 4 and poor in no patient, and the excellent and good rate was 87.9%. Different types of fractures should choose different surgical methods according to their characters. The excellent functional recovery depend on anatomical reduction, retaining the head of radius, early repairing and protecting the broken annular ligament of radius, and early functional training.

Femoral Access PCI in a Default Radial Center Identifies High-Risk Patients With Poor Outcomes.

PubMed

Uddin, Muezz; Bundhoo, Shantu; Mitra, Rito; Ossei-Gerning, Nicholas; Morris, Keith; Anderson, Richard; Kinnaird, Tim

2015-10-01

Increasingly the trans-radial route (TRR) is preferred over the trans-femoral route (TFR) for PCI. However, even in high volume default TRR centers a cohort of patients undergo TFR PCI. We examined the demographics, procedural characteristics, and outcomes of patients undergoing PCI via the TF. The patient demographics, procedural data, and outcomes of 5,379 consecutive patients undergoing PCI at a default radial center between 2009 and 2012 were examined. Major bleeding (MB) was classified by ACUITY and BARC definitions. A total of 559 (10.4%) patients underwent PCI via the TFR and 4,820 patients via the TRR (89.6%). Baseline variables associated with TFR were shock, previous CABG, chronic total occlusion intervention, rotablation/laser use, female sex, and renal failure. Sixty-five patients of the TFR cohort (11.6%) experienced MB with 27 (41.5%) being access site related. MB was significantly more frequent than in the radial cohort. The variables independently associated with MB in the TFR cohort were renal failure, acute presentation, shock, and age. In the TFR, patients with MB mortality was high at 30 days (17.2% vs 2.6% for no MB, P < 0.0001) and at 1 year (37.6% vs 5.0%, P < 0.0001). Shock and MB were highly predictive of 30 day and 12 month mortality. In a default radial PCI center 10% of patients undergo PCI via the femoral artery. These patients have high baseline bleeding risk and undergo complex interventions. As a result the incidence of major bleeding, transfusion and death are high. Alternative strategies are required to optimize outcomes in this select group. © 2015, Wiley Periodicals, Inc.

Doppler ultrasound study of penis in men with systemic sclerosis: a correlation with Doppler indices of renal and digital arteries.

PubMed

Rosato, E; Barbano, B; Gigante, A; Cianci, R; Molinaro, I; Quarta, S; Digiulio, M A; Messineo, D; Pisarri, S; Salsano, F

2013-01-01

Erectile dysfunction (ED) prevalence in male systemic sclerosis (SSc) is high and its pathogenesis is unclear. The aim of the study is to assess correlation between Doppler ultrasound indices of penis and kidneys or digital arteries in male systemic sclerosis. Fourteen men with systemic sclerosis were enrolled in this study. Erectile function was investigated by the International Index of Erectile Function-5. Peak systolic velocity, end diastolic velocity, resistive index, pulsative index, and systolic/diastolic ratio were measured on the cavernous arteries at the peno-scrotal junction in the flaccid state, on the interlobar artery of both kidneys and all ten proper palmar digital arteries. Ten (71 percent) patients have an International Index of Erectile Function-5 less than 21. Reduction of penis peak systolic velocity was observed in all SSc subjects. Doppler indices of cavernous arteries correlate with the International Index of Erectile Function-5. The renal and digital arteries resistive index demonstrated a good correlation (p less than 0.0001) with International Index of Erectile Function-5. A positive correlation exists between penis and kidney arteries Doppler indices: end diastolic velocity (p less than 0.05, r=0.54), resistive index (p less than 0.0001, r=0.90), systolic/diastolic ratio (p less than 0.01, r=0.69). A positive correlation was observed between penis and digital arteries Doppler indices: peak systolic velocity (p less than 0.01, r=0.68), end diastolic velocity (p less than 0.01, r=0.75), resistive index (p less than 0.001, r=0.79), systolic/diastolic ratio (p less than 0.05, r=0.59). A correlation exists between arterial impairment of penis and renal or digital arteries.

Impact of functional focal versus diffuse coronary artery disease on bypass graft patency.

PubMed

Shiono, Yasutsugu; Kubo, Takashi; Honda, Kentaro; Katayama, Yosuke; Aoki, Hiroshi; Satogami, Keisuke; Kashiyama, Kuninobu; Taruya, Akira; Nishiguchi, Tsuyoshi; Kuroi, Akio; Orii, Makoto; Kameyama, Takeyoshi; Yamano, Takashi; Yamaguchi, Tomoyuki; Matsuo, Yoshiki; Ino, Yasushi; Tanaka, Atsushi; Hozumi, Takeshi; Nishimura, Yoshiharu; Okamura, Yoshitaka; Akasaka, Takashi

2016-11-01

Pressure guidewire pullback recording can differentiate between functional focal and diffuse disease types in coronary artery disease. The aim of this study was to compare the outcome of coronary artery bypass graft (CABG) patency between patients with functional focal versus diffuse disease types in recipient coronary arteries. We investigated 89 patients who underwent pressure guidewire pullback in the left anterior descending (LAD) artery before CABG using internal mammary artery (IMA). Based on the pressure guidewire pullback data, the LAD lesions were classified into functional focal disease (abrupt pressure step-up; n=58) or functional diffuse disease (gradual pressure increase; n=31). Follow-up computed tomography (CT) angiography was conducted within 1year after CABG to assess the bypass graft patency. Pre CABG, LAD angiographic percent diameter stenosis (57±10% vs. 54±12%, p=0.228) and fractional flow reserve (FFR) (0.68±0.07 vs. 0.69±0.07, p=0.244) were not different between the functional focal and diffuse disease groups. The CABG procedure characteristics were similarly comparable between the two groups. In the follow-up CT angiography after CABG, occlusion or string sign of the IMA graft to LAD was more frequently observed in the functional diffuse disease group than in the functional focal disease group (26% vs. 7%, p=0.021). In CABG, functional diffuse disease in the recipient coronary artery was associated with an increased risk of the graft failure in comparison with functional focal disease. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Estimation of arterial input by a noninvasive image derived method in brain H2 15O PET study: confirmation of arterial location using MR angiography

NASA Astrophysics Data System (ADS)

Muinul Islam, Muhammad; Tsujikawa, Tetsuya; Mori, Tetsuya; Kiyono, Yasushi; Okazawa, Hidehiko

2017-06-01

A noninvasive method to estimate input function directly from H2 15O brain PET data for measurement of cerebral blood flow (CBF) was proposed in this study. The image derived input function (IDIF) method extracted the time-activity curves (TAC) of the major cerebral arteries at the skull base from the dynamic PET data. The extracted primordial IDIF showed almost the same radioactivity as the arterial input function (AIF) from sampled blood at the plateau part in the later phase, but significantly lower radioactivity in the initial arterial phase compared with that of AIF-TAC. To correct the initial part of the IDIF, a dispersion function was applied and two constants for the correction were determined by fitting with the individual AIF in 15 patients with unilateral arterial stenoocclusive lesions. The area under the curves (AUC) from the two input functions showed good agreement with the mean AUCIDIF/AUCAIF ratio of 0.92  ±  0.09. The final products of CBF and arterial-to-capillary vascular volume (V 0) obtained from the IDIF and AIF showed no difference, and had with high correlation coefficients.

Combined Use of Bivalirudin and Radial Access in Acute Coronary Syndromes Is Not Superior to the Use of Either One Separately: Meta-Analysis of Randomized Controlled Trials.

PubMed

Mina, George S; Gobrial, George F; Modi, Kalgi; Dominic, Paari

2016-08-08

The aim of this meta-analysis was to study the relation between access site and bivalirudin use on outcomes in patients with acute coronary syndrome (ACS). Bivalirudin and radial access use are 2 strategies that are increasingly used to lower major bleeding in patients with ACS undergoing invasive approaches. The interaction between these 2 strategies and the benefit of using them in combination are unclear. This analysis included randomized controlled trials that compared bivalirudin to heparin with or without glycoprotein IIb/IIIa inhibitors in patients with ACS and reported outcomes stratified by arterial access site. Meta-analyses of outcome data were performed on the basis of access site and anticoagulation regimen. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were calculated from event rates using random-effects models. Eight trials with a total of 27,491 patients were included. Bivalirudin reduced major bleeding risk in patients with femoral access (OR: 0.51; 95% CI: 0.46 to 0.6; p < 0.001) but not in patients with radial access (OR: 0.75; 95% CI: 0.45 to 1.26; p = 0.28). Moreover, radial access reduced major bleeding risk in patients treated with heparin (OR: 0.57; 95% CI: 0.43 to 0.77; p < 0.001) but not in patients treated with bivalirudin (OR: 0.96; 95% CI: 0.65 to 1.41; p = 0.83). There were no differences in major adverse cardiovascular events or all-cause mortality between bivalirudin and heparin, regardless of access site. Bivalirudin reduces bleeding risk only with femoral access, and radial access reduces bleeding risk only with heparin anticoagulation. Therefore, there is no additional benefit to the combined use of bivalirudin and radial access strategies in patients with ACS. Copyright © 2016 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Comparison of Safety and Effectiveness Between Right Versus Left Radial Arterial Access in Primary Percutaneous Coronary Intervention for Acute ST Segment Elevation Myocardial Infarction.

PubMed

Elmahdy, Mahmoud Farouk; ElMaghawry, Mohamed; Hassan, Mohamed; Kassem, Hussien Heshmat; Said, Karim; Elfaramawy, Amr AbdelAziz

2017-01-01

Transradial approach (TRA) is now considered the standard of care in many centres for elective and primary percutaneous intervention (PCI). The use of the radial approach in ST segment elevation myocardial infarction (STEMI) patients has been associated with a significant reduction in major adverse cardiac events. However, it is still unclear if the side of radial access (right vs. left) has impact on safety and effectiveness of TRA in primary PCI. So this study was conducted to compare the safety, feasibility, and outcomes of right radial access (RRA) vs. left radial access (LRA) in the setting of primary PCI. We retrospectively analysed the data of 400 consecutive patients presenting to our institution with STEMI for whom primary PCIs were performed via RRA and LRA. Mean age of the whole studied population was 57±12.8 years, with male predominance (77.2%). There were 202 cases in the RRA group and 198 in the LRA group, with no significant difference in demographics and clinical characteristics for patients included in both groups. There was no significant difference in procedure success rate (97.5% for RRA vs. 98.4% for LRA; P=0.77). In addition, no significant difference between both approaches was observed in the contrast volume, number of catheters, fluoroscopy time (FT), needle-to-balloon time, post-procedure vascular complications, in hospital reinfarction, stroke/transient ischaemic attack (TIA) or death. Right radial access and LRA are equally safe and effective in the setting of primary PCI. Both approaches have a high success rate and comparable needle-to-balloon time. Copyright © 2016 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.

Functional Dicer Is Necessary for Appropriate Specification of Radial Glia during Early Development of Mouse Telencephalon

PubMed Central

Nowakowski, Tomasz Jan; Mysiak, Karolina Sandra; Pratt, Thomas; Price, David Jonathan

2011-01-01

Early telencephalic development involves transformation of neuroepithelial stem cells into radial glia, which are themselves neuronal progenitors, around the time when the tissue begins to generate postmitotic neurons. To achieve this transformation, radial precursors express a specific combination of proteins. We investigate the hypothesis that micro RNAs regulate the ability of the early telencephalic progenitors to establish radial glia. We ablate functional Dicer, which is required for the generation of mature micro RNAs, by conditionally mutating the Dicer1 gene in the early embryonic telencephalon and analyse the molecular specification of radial glia as well as their progeny, namely postmitotic neurons and basal progenitors. Conditional mutation of Dicer1 from the telencephalon at around embryonic day 8 does not prevent morphological development of radial glia, but their expression of Nestin, Sox9, and ErbB2 is abnormally low. The population of basal progenitors, which are generated by the radial glia, is disorganised and expanded in Dicer1-/- dorsal telencephalon. While the proportion of cells expressing markers of postmitotic neurons is unchanged, their laminar organisation in the telencephalic wall is disrupted suggesting a defect in radial glial guided migration. We found that the laminar disruption could not be accounted for by a reduction of the population of Cajal Retzius neurons. Together, our data suggest novel roles for micro RNAs during early development of progenitor cells in the embryonic telencephalon. PMID:21826226

Functional dicer is necessary for appropriate specification of radial glia during early development of mouse telencephalon.

PubMed

Nowakowski, Tomasz Jan; Mysiak, Karolina Sandra; Pratt, Thomas; Price, David Jonathan

2011-01-01

Early telencephalic development involves transformation of neuroepithelial stem cells into radial glia, which are themselves neuronal progenitors, around the time when the tissue begins to generate postmitotic neurons. To achieve this transformation, radial precursors express a specific combination of proteins. We investigate the hypothesis that micro RNAs regulate the ability of the early telencephalic progenitors to establish radial glia. We ablate functional Dicer, which is required for the generation of mature micro RNAs, by conditionally mutating the Dicer1 gene in the early embryonic telencephalon and analyse the molecular specification of radial glia as well as their progeny, namely postmitotic neurons and basal progenitors. Conditional mutation of Dicer1 from the telencephalon at around embryonic day 8 does not prevent morphological development of radial glia, but their expression of Nestin, Sox9, and ErbB2 is abnormally low. The population of basal progenitors, which are generated by the radial glia, is disorganised and expanded in Dicer1⁻/⁻ dorsal telencephalon. While the proportion of cells expressing markers of postmitotic neurons is unchanged, their laminar organisation in the telencephalic wall is disrupted suggesting a defect in radial glial guided migration. We found that the laminar disruption could not be accounted for by a reduction of the population of Cajal Retzius neurons. Together, our data suggest novel roles for micro RNAs during early development of progenitor cells in the embryonic telencephalon.

Ultrasound-guided axillary brachial plexus block versus local infiltration anesthesia for arteriovenous fistula creation at the forearm for hemodialysis in patients with chronic renal failure.

PubMed

Nofal, W H; El Fawal, S M; Shoukry, A A; Sabek, Eas; Malak, Wfa

2017-01-01

The primary failure rate for arteriovenous fistula (AVF) creation under local anesthesia for hemodialysis is about 30%. Axillary brachial plexus block (BPB) may improve blood flow through blood vessels used in fistula creation; it may improve the AVF blood flow and thus may reduce the primary failure rate after 3 months. Hundred and forty patients with chronic renal failure scheduled for AVF creation for hemodialysis were divided into two equal groups; Group 1 (AxBP-G) received ultrasound (US) guided axillary BPB, and Group 2 (LI-G) received local infiltration. We recorded the measurements of the brachial and radial arteries before and after anesthesia and the AVF blood flow in both groups at three different time points. Furthermore, the primary failure rate was recorded in each group and compared. After anesthesia, the mean radial artery blood flow in the AxBP-group was 3.52 ml/min more than the LI-group, and the brachial artery diameter was also 0.68 mm more than in the LI-group, both differences were statistically significant ( P < 0.05). There were significant increases ( P < 0.05) in the AVF blood flow in the AxBP-group more than the LI-group with mean differences of 29.6, 69.8, and 27.2 ml/min at 4 h, 1 week, and 3 months, respectively. The overall mean of AVF blood flow was 42.21 ml/min more in the AxBP group than the LI-group a difference which is statistically significant ( P < 0.001). The primary failure rate was 17% in the AxBP group versus 30% in the LI-group; however, this difference is not significant statistically ( P = 0.110). The US-guided axillary block increases AVF blood flow significantly more than local infiltration and nonsignificantly decreases the primary failure rate of the AVF after 3 months.

Aperiodic Photonic-Plasmonic Structures with Broadband Field Enhancement

DTIC Science & Technology

2012-10-15

monomer, (d and g) dimer, (e and i ) trimer...components of the radial distribution function. (a-d) numerator, (e-h) denominator, ( i -l) entire radial distribution function...in the Y direction is 400 nm. Fig 7 d- i shows the scattering efficiency and maximum field enhancement of each array compared with that of the

Development of functional in vivo imaging of cerebral lenticulostriate artery using novel synchrotron radiation angiography

NASA Astrophysics Data System (ADS)

Lin, Xiaojie; Miao, Peng; Mu, Zhihao; Jiang, Zhen; Lu, Yifan; Guan, Yongjing; Chen, Xiaoyan; Xiao, Tiqiao; Wang, Yongting; Yang, Guo-Yuan

2015-02-01

The lenticulostriate artery plays a vital role in the onset and development of cerebral ischemia. However, current imaging techniques cannot assess the in vivo functioning of small arteries such as the lenticulostriate artery in the brain of rats. Here, we report a novel method to achieve a high resolution multi-functional imaging of the cerebrovascular system using synchrotron radiation angiography, which is based on spatio-temporal analysis of contrast density in the arterial cross section. This method provides a unique tool for studying the sub-cortical vascular elasticity after cerebral ischemia in rats. Using this technique, we demonstrated that the vascular elasticity of the lenticulostriate artery decreased from day 1 to day 7 after transient middle cerebral artery occlusion in rats and recovered from day 7 to day 28 compared to the controls (p < 0.001), which paralleled with brain edema formation and inversely correlated with blood flow velocity (p < 0.05). Our results demonstrated that the change of vascular elasticity was related to the levels of brain edema and the velocity of focal blood flow, suggesting that reducing brain edema is important for the improvement of the function of the lenticulostriate artery in the ischemic brain.

Optimized Reduction of Unsteady Radial Forces in a Singlechannel Pump for Wastewater Treatment

NASA Astrophysics Data System (ADS)

Kim, Jin-Hyuk; Cho, Bo-Min; Choi, Young-Seok; Lee, Kyoung-Yong; Peck, Jong-Hyeon; Kim, Seon-Chang

2016-11-01

A single-channel pump for wastewater treatment was optimized to reduce unsteady radial force sources caused by impeller-volute interactions. The steady and unsteady Reynolds- averaged Navier-Stokes equations using the shear-stress transport turbulence model were discretized by finite volume approximations and solved on tetrahedral grids to analyze the flow in the single-channel pump. The sweep area of radial force during one revolution and the distance of the sweep-area center of mass from the origin were selected as the objective functions; the two design variables were related to the internal flow cross-sectional area of the volute. These objective functions were integrated into one objective function by applying the weighting factor for optimization. Latin hypercube sampling was employed to generate twelve design points within the design space. A response-surface approximation model was constructed as a surrogate model for the objectives, based on the objective function values at the generated design points. The optimized results showed considerable reduction in the unsteady radial force sources in the optimum design, relative to those of the reference design.

Comparison of the transplacental pharmacokinetics of cortisol and triamcinolone acetonide in the rhesus monkey

DOE Office of Scientific and Technical Information (OSTI.GOV)

Slikker, W. Jr.; Althaus, Z.R.; Rowland, J.M.

1982-11-01

The late gestational age rhesus monkey was used to study the transplacental pharmacokinetics of radiolabeled triamcinolone acetonide (TAC) and cortisol. Tritiated-TAC and (/sup 14/C)cortisol were administered simultaneously via the maternal radial vein were administered simultaneously via the maternal radial vein and blood samples were serially drawn from catheters implanted in both the maternal femoral artery and fetal umbilical vein and artery. High-performance liquid chromatography of the processed blood samples revealed that from 93 to 100% of the /sup 3/H in the fetal circulation was parent TAC, whereas only 14 to 49% of the /sup 14/C was cortisol during the 40-minmore » period after dose administration. Fetal tissue samples taken at 3 hr after dose administration showed that 75 to 96% of the /sup 3/H present was TAC, whereas no cortisol was observed. TAC demonstrated dose-independent kinetics. Samples collected from the umbilical vein of the in situ placenta after fetectomy revealed that cortisol was extensively converted to cortisone by the placenta, whereas TAC was refractory to placental metabolism. This placental conversion of cortisol to cortisone and the further metabolism and conjugation of cortisol by the fetoplacental unit resulted in a fetal to maternal plasma cortisol ratio of 0.2. In contrast, the lack of placental or fetoplacental metabolism of TAC resulted in a fetal to maternal plasma TAC ratio of 0.6.« less

Numerical Technique for Analyzing Rotating Rake Mode Measurements in a Duct With Passive Treatment and Shear Flow

NASA Technical Reports Server (NTRS)

Dahl, Milo D.; Sutliff, Daniel L.

2007-01-01

A technique is presented for the analysis of measured data obtained from a rotating microphone rake system. The system is designed to measure the interaction modes of ducted fans. A Fourier analysis of the data from the rotating system results in a set of circumferential mode levels at each radial location of a microphone inside the duct. Radial basis functions are then least-squares fit to this data to obtain the radial mode amplitudes. For ducts with soft walls and mean flow, the radial basis functions must be numerically computed. The linear companion matrix method is used to obtain both the eigenvalues of interest, without an initial guess, and the radial basis functions. The governing equations allow for the mean flow to have a boundary layer at the wall. In addition, a nonlinear least-squares method is used to adjust the wall impedance to best fit the data in an attempt to use the rotating system as an in-duct wall impedance measurement tool. Simulated and measured data are used to show the effects of wall impedance and mean flow on the computed results.

PCA-based polling strategy in machine learning framework for coronary artery disease risk assessment in intravascular ultrasound: A link between carotid and coronary grayscale plaque morphology.

PubMed

Araki, Tadashi; Ikeda, Nobutaka; Shukla, Devarshi; Jain, Pankaj K; Londhe, Narendra D; Shrivastava, Vimal K; Banchhor, Sumit K; Saba, Luca; Nicolaides, Andrew; Shafique, Shoaib; Laird, John R; Suri, Jasjit S

2016-05-01

Percutaneous coronary interventional procedures need advance planning prior to stenting or an endarterectomy. Cardiologists use intravascular ultrasound (IVUS) for screening, risk assessment and stratification of coronary artery disease (CAD). We hypothesize that plaque components are vulnerable to rupture due to plaque progression. Currently, there are no standard grayscale IVUS tools for risk assessment of plaque rupture. This paper presents a novel strategy for risk stratification based on plaque morphology embedded with principal component analysis (PCA) for plaque feature dimensionality reduction and dominant feature selection technique. The risk assessment utilizes 56 grayscale coronary features in a machine learning framework while linking information from carotid and coronary plaque burdens due to their common genetic makeup. This system consists of a machine learning paradigm which uses a support vector machine (SVM) combined with PCA for optimal and dominant coronary artery morphological feature extraction. Carotid artery proven intima-media thickness (cIMT) biomarker is adapted as a gold standard during the training phase of the machine learning system. For the performance evaluation, K-fold cross validation protocol is adapted with 20 trials per fold. For choosing the dominant features out of the 56 grayscale features, a polling strategy of PCA is adapted where the original value of the features is unaltered. Different protocols are designed for establishing the stability and reliability criteria of the coronary risk assessment system (cRAS). Using the PCA-based machine learning paradigm and cross-validation protocol, a classification accuracy of 98.43% (AUC 0.98) with K=10 folds using an SVM radial basis function (RBF) kernel was achieved. A reliability index of 97.32% and machine learning stability criteria of 5% were met for the cRAS. This is the first Computer aided design (CADx) system of its kind that is able to demonstrate the ability of coronary risk assessment and stratification while demonstrating a successful design of the machine learning system based on our assumptions. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

CONORBIT: constrained optimization by radial basis function interpolation in trust regions

DOE PAGES

Regis, Rommel G.; Wild, Stefan M.

2016-09-26

Here, this paper presents CONORBIT (CONstrained Optimization by Radial Basis function Interpolation in Trust regions), a derivative-free algorithm for constrained black-box optimization where the objective and constraint functions are computationally expensive. CONORBIT employs a trust-region framework that uses interpolating radial basis function (RBF) models for the objective and constraint functions, and is an extension of the ORBIT algorithm. It uses a small margin for the RBF constraint models to facilitate the generation of feasible iterates, and extensive numerical tests confirm that such a margin is helpful in improving performance. CONORBIT is compared with other algorithms on 27 test problems, amore » chemical process optimization problem, and an automotive application. Numerical results show that CONORBIT performs better than COBYLA, a sequential penalty derivative-free method, an augmented Lagrangian method, a direct search method, and another RBF-based algorithm on the test problems and on the automotive application.« less

[General anesthesia for a patient with pulmonary hypertension, bronchial asthma and obesity].

PubMed

Nakamura, Shinji; Nishiyama, Tomoki; Hanaoka, Kazuo

2005-10-01

The management of the patient with pulmonary hypertension is a challenge for the anesthesiologists because the risk of right-sided heart failure is markedly increased. We experienced a case of general anesthesia for a patient with pulmonary hypertension (mean pulmonary arterial pressure 39 mmHg), bronchial asthma and obesity. A 31-year-old woman was scheduled for arytenoid rotation for left recurrent nerve palsy. We applied routine monitors (noninvasive blood-pressure, five-lead electrocardiogram, pulse oximeter), and direct blood pressure monitoring through the radial artery. Anesthesia was induced with midazolam 4 mg, fentanyl 100 microg and sevoflurane 5%, and maintained with sevoflurane (1-2%) and nitrous oxide in oxygen. Surgery was completed in 100 minutes without any complications. We could successfully perform general anesthesia in a patient complicated by pulmonary hypertension, bronchial asthma and obesity, without invasive right-sided heart catheterization.

Perforator-based propeller flaps reliability in upper extremity soft tissue reconstruction: a systematic review.

PubMed

Vitse, J; Bekara, F; Bertheuil, N; Sinna, R; Chaput, B; Herlin, C

2017-02-01

Current data on upper extremity propeller flaps are poor and do not allow the assessment of the safety of this technique. A systematic literature review was conducted searching PubMed, EMBASE, and the Cochrane Library electronic databases, and the selection process was adapted from the preferred reporting items for systematic reviews and meta-analysis statement. The final analysis included ten relevant articles involving 117 flaps. The majority of flaps were used for the hand, distal wrist, and elbow. The radial artery perforator and ulnar artery perforator were the most frequently used flaps. The were 7% flaps with venous congestion and 3% with complete necrosis. No difference in complications rate was found for different flaps sites. Perforator-based propeller flaps appear to be an interesting procedure for covering soft tissue defects involving the upper extremities, even for large defects, but the procedure requires experience and close monitoring. II.

Innervated boomerang flap for finger pulp reconstruction.

PubMed

Chen, Shao-Liang; Chiou, Tai-Fung

2007-11-01

The boomerang flap originates from the dorsolateral aspect of the proximal phalanx of an adjacent digit and is supplied by the retrograde blood flow through the vascular arcades between the dorsal and palmar digital arteries. To provide sensation of the boomerang flap for finger pulp reconstruction, the dorsal sensory branch of the proper digital nerve and the superficial sensory branch of the corresponding radial or ulnar nerve are included within the skin flap. After transfer of the flap to the injured site, epineural neurorrhaphies are done between the digital nerves of the pulp and the sensory branches of the flap. We used this sensory flap in five patients, with more than 1 year follow-up, and all patients achieved measurable two-points discrimination. The boomerang flap not only preserves the proper palmar digital artery but also provides an extended and innervated skin paddle. It seems to be an alternative choice for one-stage reconstruction of major pulp defect.

Activity of the right cardiac ventricle and metabolism in healthy persons during an orthostatic test after short term immobilization

NASA Technical Reports Server (NTRS)

Chestukhin, V. V.; Katkov, V. Y.; Seid-Gusaynov, A. A.; Shalnev, B. I.; Georgiyevskiy, V. S.; Zybin, O. K.; Mikhaylov, V. M.; Utkin, V. N.

1981-01-01

A 15 minute orthostatic test was performed on healthy male volunteers under conditions of catheterization of the right ventricle of the heart and the radial (or brachial) artery before and after 5 day bedrest in an antiorthostatic position of the body (with the foot of the bed raised 4.5 degrees). The change to a vertical position after immobilization was attended by a more marked increase in the rate of cardiac contractions, an increase of max dp/dt pressure in the right ventricle, and a decrease of cardiac and stroke indices. The decrease of the cardiac index was compensated for, to a certain measure, by a further increase in the extraction and utilization of O2 by the tissues. The arterial blood pH did not change essentially, while the decrease in pCO2 and content of standard bicarbonate was more marked.

Respiratory Motion-Resolved Compressed Sensing Reconstruction of Free-Breathing Radial Acquisition for Dynamic Liver MRI

PubMed Central

Chandarana, Hersh; Feng, Li; Ream, Justin; Wang, Annie; Babb, James S; Block, Kai Tobias; Sodickson, Daniel K; Otazo, Ricardo

2015-01-01

Purpose Demonstrate feasibility of free-breathing radial acquisition with respiratory motion-resolved compressed sensing (CS) reconstruction (XD-GRASP) for multiphase dynamic Gd-EOB-DTPA enhanced liver imaging, and compare image quality to CS reconstruction with respiratory motion-averaging (GRASP) and prior conventional breath-held Cartesian-sampled datasets (BH-VIBE) in same patients. Subjects and Methods In this HIPAA-compliant prospective study, 16 subjects underwent free-breathing continuous radial acquisition during Gd-EOB-DTPA injection, and had prior BH-VIBE exam available. Acquired data were reconstructed using motion-averaging GRASP approach, in which consecutive 84-spokes were grouped in each contrast-enhanced phase for a temporal resolution of ~14 seconds. Additionally, respiratory motion-resolved reconstruction was performed from the same k-space data, by sorting each contrast-enhanced phase into multiple respiratory motion states using compressed sensing algorithm named XD-GRASP, which exploits sparsity along both the contrast-enhancement and respiratory-state dimensions. Contrast-enhanced dynamic multi-phase XD-GRASP, GRASP, and BH-VIBE images were anonymized, pooled together in a random order and presented to two board-certified radiologists for independent evaluation of image quality, with higher score indicating more optimal exam. Results XD-GRASP reconstructions had significantly (all p<0.05) higher overall image quality scores compared to GRASP for early arterial (Reader 1: 4.3 ± 0.6 vs. 3.31 ± 0.6 ; Reader 2: 3.81 ± 0.8 vs. 3.38 ± 0.9) and late arterial (Reader 1: 4.5 ± 0.6 vs. 3.63 ± 0.6; Reader 2: 3.56 ± 0.5 vs. 2.88 ± 0.7) phases of enhancement for both readers. XD-GRASP also had higher overall image quality score in portal venous phase which was significant for Reader 1 (4.44 ± 0.5 vs. 3.75 ± 0.8; p=0.002). In addition, XD-GRASP had higher overall image quality score compared to BH-VIBE for early (Reader 1: 4.3±0.6 vs. 3.88±0.6; Reader 2: 3.81±0.8 vs. 3.50±1.0) and late (Reader 1: 4.5±0.6 vs. 3.44±0.6; Reader 2: 3.56±0.5 vs. 2.94±0.9) arterial phases. Conclusion Free-breathing motion-resolved XD-GRASP reconstructions provide diagnostic high-quality multiphase images in patients undergoing Gd-EOB-DTPA-enhanced liver exam. PMID:26146869

VizieR Online Data Catalog: Tracers of the Milky Way mass (Bratek+, 2014)

NASA Astrophysics Data System (ADS)

Bratek, L.; Sikora, S.; Jalocha, J.; Kutschera, M.

2013-11-01

We model the phase-space distribution of the kinematic tracers using general, smooth distribution functions to derive a conservative lower bound on the total mass within ~~150-200kpc. By approximating the potential as Keplerian, the phase-space distribution can be simplified to that of a smooth distribution of energies and eccentricities. Our approach naturally allows for calculating moments of the distribution function, such as the radial profile of the orbital anisotropy. We systematically construct a family of phase-space functions with the resulting radial velocity dispersion overlapping with the one obtained using data on radial motions of distant kinematic tracers, while making no assumptions about the density of the tracers and the velocity anisotropy parameter β regarded as a function of the radial variable. While there is no apparent upper bound for the Milky Way mass, at least as long as only the radial motions are concerned, we find a sharp lower bound for the mass that is small. In particular, a mass value of 2.4x1011M⊙, obtained in the past for lower and intermediate radii, is still consistent with the dispersion profile at larger radii. Compared with much greater mass values in the literature, this result shows that determining the Milky Way mass is strongly model-dependent. We expect a similar reduction of mass estimates in models assuming more realistic mass profiles. (1 data file).

Analytical Solutions of the Schrödinger Equation for the Manning-Rosen plus Hulthén Potential Within SUSY Quantum Mechanics

NASA Astrophysics Data System (ADS)

Ahmadov, A. I.; Naeem, Maria; Qocayeva, M. V.; Tarverdiyeva, V. A.

2018-02-01

In this paper, the bound state solution of the modified radial Schrödinger equation is obtained for the Manning-Rosen plus Hulthén potential by implementing the novel improved scheme to surmount the centrifugal term. The energy eigenvalues and corresponding radial wave functions are defined for any l ≠ 0 angular momentum case via the Nikiforov-Uvarov (NU) and supersymmetric quantum mechanics (SUSYQM) methods. By using these two different methods, equivalent expressions are obtained for the energy eigenvalues, and the expression of radial wave functions transformations to each other is demonstrated. The energy levels are worked out and the corresponding normalized eigenfunctions are represented in terms of the Jacobi polynomials for arbitrary l states. A closed form of the normalization constant of the wave functions is also found. It is shown that, the energy eigenvalues and eigenfunctions are sensitive to nr radial and l orbital quantum numbers.

A radially resolved kinetic model for nonlocal electron ripple diffusion losses in tokamaks

DOE Office of Scientific and Technical Information (OSTI.GOV)

Robertson, Scott

A relatively simple radially resolved kinetic model is applied to the ripple diffusion problem for electrons in tokamaks. The distribution function f(r,v) is defined on a two-dimensional grid, where r is the radial coordinate and v is the velocity coordinate. Particle transport in the radial direction is from ripple and banana diffusion and transport in the velocity direction is described by the Fokker-Planck equation. Particles and energy are replaced by source functions that are adjusted to maintain a constant central density and temperature. The relaxed profiles of f(r,v) show that the electron distribution function at the wall contains suprathermal electronsmore » that have diffused from the interior that enhance ripple transport. The transport at the periphery is therefore nonlocal. The energy replacement times from the computational model are near to the experimental replacement times for tokamak discharges in the compilation by Pfeiffer and Waltz [Nucl. Fusion 19, 51 (1979)].« less

Novel Integration Radial and Axial Magnetic Bearing

NASA Technical Reports Server (NTRS)

Blumenstock, Kenneth; Brown, Gary

2000-01-01

Typically, fully active magnetically suspended systems require one axial and two radial magnetic bearings. Combining radial and axial functions into a single device allows for more compact and elegant packaging. Furthermore, in the case of high-speed devices such as energy storage flywheels, it is beneficial to minimize shaft length to keep rotor mode frequencies as high as possible. Attempts have been made to combine radial and axial functionality, but with certain drawbacks. One approach requires magnetic control flux to flow through a bias magnet reducing control effectiveness, thus resulting in increased resistive losses. This approach also requires axial force producing magnetic flux to flow in a direction into the rotor laminate that is undesirable for minimizing eddy-current losses resulting in rotational losses. Another approach applies a conical rotor shape to what otherwise would be a radial heteropolar magnetic bearing configuration. However, positional non-linear effects are introduced with this scheme and the same windings are used for bias, radial, and axial control adding complexity to the controller and electronics. For this approach, the amount of axial capability must be limited. It would be desirable for an integrated radial and axial magnetic bearing to have the following characteristics; separate inputs for radial and axial control for electronics and control simplicity, all magnetic control fluxes should only flow through their respective air gaps and should not flow through any bias magnets for minimal resistive losses, be of a homopolar design to minimize rotational losses, position related non-linear effects should be minimized, and dependent upon the design parameters, be able to achieve any radial/axial force or power ratio as desired. The integrated radial and axial magnetic bearing described in this paper exhibits all these characteristics. Magnetic circuit design, design equations, and magnetic field modeling results will be presented.

Novel Integrated Radial and Axial Magnetic Bearing

NASA Technical Reports Server (NTRS)

Blumenstock, Kenneth A.; Brown, Gary L.; Powers, Edward I. (Technical Monitor)

2000-01-01

Typically, fully active magnetically suspended systems require one axial and two radial magnetic bearings. Combining radial and axial functions into a single device allows for more compact and elegant packaging. Furthermore, in the case of high-speed devices such as energy storage flywheels, it is beneficial to minimize shaft length to keep rotor mode frequencies as high as possible. Attempts have been made to combine radial and axial functionality, but with certain drawbacks. One approach requires magnetic control flux to flow through a bias magnet reducing control effectiveness, thus resulting in increased resistive losses. This approach also requires axial force producing magnetic flux to flow in a direction into the rotor laminate that is undesirable for minimizing eddy-current losses resulting in rotational losses. Another approach applies a conical rotor shape to what otherwise would be a radial heteropolar magnetic bearing configuration. However, positional non-linear effects are introduced with this scheme and the same windings are used for bias, radial, and axial control adding complexity to the controller and electronics. For this approach, the amount of axial capability must be limited. It would be desirable for an integrated radial and axial magnetic bearing to have the following characteristics, separate inputs for radial and axial control for electronics and control simplicity, all magnetic control fluxes should only flow through their respective air gaps and should not flow through any bias magnets for minimal resistive losses, be of a homopolar design to minimize rotational losses, position related non-linear effects should be minimized, and dependent upon the design parameters, be able to achieve any radial/axial force or power ratio as desired. The integrated radial and axial magnetic bearing described in this paper exhibits all these characteristics. Magnetic circuit design, design equations, and analysis results will be presented.

Does arterial health affect VO2peak and muscle oxygenation in a sedentary cohort?

PubMed

Lizamore, Catherine Anne; Stoner, Lee; Lucas, Samuel John Edwin; Lucero, Adam; Hamlin, Michael John

2015-02-01

An association between arterial health and peak oxygen consumption (VO2peak) has been demonstrated; however, little is known about how arterial health influences muscular oxygenation during exercise. The aim of this study was to gain insight into the relations between arterial health, VO2peak, and muscle oxygenation in a middle-age sedentary population. Radial augmentation index (AIx) (via pulse wave analysis) of 21 sedentary middle-age participants (15 females and six males; age, 54.7 ± 5.4; body mass index, 29.0 ± 4.7 kg·m; mean ± SD) was assessed, and on another day ( < 7 d), participants completed a modified Bruce protocol (MBP). Using near-infrared spectroscopy, total oxygenation index (TOI) of the left flexor carpi ulnaris and the left vastus lateralis were monitored throughout the MBP. Independent and average (arm + leg) percentage decrease in TOI between stage 1 of the MBP and maximal exertion (TOIdiff) during MBP was calculated. Changes between dependent variables were correlated using Pearson product-moment correlations and were interpreted as follows: r > 0.5, strong; 0.5 > r > 0.3, moderate; and r < 0.3, weak. We observed moderate negative correlation between AIx and VO2peak (r = -0.34, -0.63 to -0.03; Pearson correlation, 90% confidence limits) and strong negative correlation between AIx and average TOIdiff (r = -0.58, -0.78 to -0.27). The VO2peak and average TOIdiff were strongly correlated (r = 0.55, 0.23-0.77). Arterial health seems to be an important determinant of muscle oxygenation during exercise. In turn, muscle oxygenation during exercise is strongly related to VO2peak. Developing training modalities to prioritize arterial health outcomes may be a useful way of improving VO2peak in this population.

Vertebral artery origin stent placement with distal protection: technical and clinical results.

PubMed

Qureshi, A I; Kirmani, J F; Harris-Lane, P; Divani, A A; Ahmed, S; Ebrihimi, A; Al Kawi, A; Janjua, N

2006-05-01

To report the feasibility, safety, and 1-month results of performing stent placement for vertebral origin stenosis with the use of a distal protection device. Distal protection devices have been shown to reduce the number of cerebral emboli and subsequent ischemic events when used as adjuncts to percutaneous carotid intervention; however, one case of the use of a distal protection device for vertebral artery has been reported in the literature. We retrospectively determined rates of technical success and 1-month stroke or death associated with stent placement by using distal protection (Filter EX; Boston Scientific, Natick, Mass) in patients with symptomatic vertebral artery origin stenosis. Technical success was defined as successful deployment of distal protection device and stent at target lesion followed by successful retrieval of the device and a final residual stenosis of less than 30%. Other outcomes ascertained included any stroke, death, and semiquantitative assessment of particulate material retained by the filter device. The mean age of the 12 treated patients was 68 years (range, 52-88 years) and the group included 9 men and 3 women. The mean percentage of vertebral artery origin stenosis was 71 +/- 6%. Femoral and radial approaches were used in 9 and 3 cases, respectively. Technical success was achieved in 11 of the 12 patients in whom distal protection device placement was attempted. Postprocedure residual stenosis was 5 +/- 4%. Eight devices held macroscopically visible embolic debris (large and small amounts in 3 and 5 devices, respectively). No stroke or death was observed in the 1-month follow-up. The present study demonstrates the feasibility of performing stent placement for vertebral artery origin stenosis by using a distal protection device. Further studies are required to determine the effectiveness of this approach for vertebral artery origin atherosclerosis.

The effects of metronome breathing on the variability of autonomic activity measurements.

PubMed

Driscoll, D; Dicicco, G

2000-01-01

Many chiropractors hypothesize that spinal manipulation affects the autonomic nervous system (ANS). However, the ANS responses to chiropractic manipulative therapy are not well documented, and more research is needed to support this hypothesis. This study represents a step toward the development of a reliable method by which to document that chiropractic manipulative therapy does affect the ANS by exploring the use of paced breathing as a way to reduce the inherent variability in ANS measurements. To examine the hypothesis that the variability of ANS measurements would be reduced if breathing were paced to a metronome at 12 breaths/min. The study was performed at Parker College Research Institute. Eight normotensive subjects were recruited from the student body and staff. Respiration frequency was measured through a strain gauge. A 3-lead electrocardiogram (ECG) was used to register the electric activity of the heart, and arterial tonometry monitors were used to record the left and right radial artery blood pressures. Signals were recorded on an IBM-compatible computer with a sampling frequency of 100 Hz. Normal breathing was used for the first 3 recordings, and breathing was paced to a metronome for the final 3 recordings at 12 breaths/min. Fourier analysis was performed on the beat-by-beat fluctuations of the ECG-determined R-R interval and systolic arterial pressure (SBP). Low-frequency fluctuations (LF; 0.04-0.15 Hz) reflected sympathetic activity, whereas high-frequency fluctuations (HF; 0.15-0.4 Hz) represented parasympathetic activity. Sympathovagal indices were determined from the ratio of the two bandwidths (LF/HF). The coefficient of variation (CV%) for autonomic parameters was calculated ([average/SD] x 100%) to compare breathing normally and breathing to a metronome with respect to variability. One-way analysis of variance was used to detect differences. A value of P < 0.05 was considered statistically significant; all results are presented as average +/- SD. Three male and 5 female normotensive subjects were studied. Metronome breathing did not produce any significant changes in blood pressure for the left and right radial arteries, heart rate, or pressure pulse transmission time. Breathing to a metronome increased ECG-HF power (0.25 +/- 0.07 vs 0.35 +/- 0.09, P < 0.04), decreased ECG-LF/HF (1.08 +/- 0.55 vs 0.57 +/- 0.35, P < 0.05), and reduced the CV% for ECG-LF (47.6% +/- 23.4% vs 23.8% +/- 14.6%, P < 0.03), ECG-HF (46.2% +/- 14.2% vs 25.8% +/- 17.0%, P < 0.03) and ECG-LF/HF (50.1% +/- 27.6% vs 23.4% +/- 12.3%, P < 0.03) in comparison with normal breathing. Metronome breathing increased the left and right radial artery SBP-HF fluctuations (left, 0.11 +/- 0.05 vs 0.30 +/- 0.16, P < 0.007; right, 0.09 +/- 0.05 vs 0.27 +/- 0.15, P < 0.008) and decreased the SBP-LF/HF components (left, 3.42 +/- 2.36 vs 1.14 +/- 0.88, P > 0.03; right, 3.08 +/- 1.77 vs 1.20 +/- 0.93, P < 0.02). Metronome breathing did not significantly alter the CV% for SBP-HF, SBP-LF, and SBP-LF/HF. Metronome breathing increased parasympathetic activity, as evidenced by augmented HF power in the ECG and SBP data. The variability (CV%) of ECG-determined ANS measurements was significantly reduced with paced breathing at 12 breaths/min, but no significant reductions were observed for the SBP-determined ANS measurements. These findings indicate that ECG data are more sensitive than SBP data for future clinical trials.

Path integral solution for a Klein-Gordon particle in vector and scalar deformed radial Rosen-Morse-type potentials

NASA Astrophysics Data System (ADS)

Khodja, A.; Kadja, A.; Benamira, F.; Guechi, L.

2017-12-01

The problem of a Klein-Gordon particle moving in equal vector and scalar Rosen-Morse-type potentials is solved in the framework of Feynman's path integral approach. Explicit path integration leads to a closed form for the radial Green's function associated with different shapes of the potentials. For q≤-1, and 1/2α ln | q|0, it is shown that the quantization conditions for the bound state energy levels E_{nr} are transcendental equations which can be solved numerically. Three special cases such as the standard radial Manning-Rosen potential (| q| =1), the standard radial Rosen-Morse potential (V2→ -V2,q=1) and the radial Eckart potential (V1→ -V1,q=1) are also briefly discussed.

Sympathetic Innervation Promotes Arterial Fate by Enhancing Endothelial ERK Activity.

PubMed

Pardanaud, Luc; Pibouin-Fragner, Laurence; Dubrac, Alexandre; Mathivet, Thomas; English, Isabel; Brunet, Isabelle; Simons, Michael; Eichmann, Anne

2016-08-19

Arterial endothelial cells are morphologically, functionally, and molecularly distinct from those found in veins and lymphatic vessels. How arterial fate is acquired during development and maintained in adult vessels is incompletely understood. We set out to identify factors that promote arterial endothelial cell fate in vivo. We developed a functional assay, allowing us to monitor and manipulate arterial fate in vivo, using arteries isolated from quails that are grafted into the coelom of chick embryos. Endothelial cells migrate out from the grafted artery, and their colonization of host arteries and veins is quantified. Here we show that sympathetic innervation promotes arterial endothelial cell fate in vivo. Removal of sympathetic nerves decreases arterial fate and leads to colonization of veins, whereas exposure to sympathetic nerves or norepinephrine imposes arterial fate. Mechanistically, sympathetic nerves increase endothelial ERK (extracellular signal-regulated kinase) activity via adrenergic α1 and α2 receptors. These findings show that sympathetic innervation promotes arterial endothelial fate and may lead to novel approaches to improve arterialization in human disease. © 2016 American Heart Association, Inc.

Restoration of Failed Renal Graft Function After Successful Angioplasty of Pressure-Resistant Renal Artery Stenosis Using a Cutting Balloon: A Case Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Peregrin, J. H., E-mail: jape@medicon.c; Buergelova, M.

2009-05-15

This study is the report of a 37-year-old male with a transplanted kidney from a 3.5-year-old donor: the graft had two arteries transplanted with an aortic patch to an external iliac artery. Four months after transplantation, the graft function deteriorated, together with the development of hypertension. Stenosis of both graft arteries was detected and the patient was referred for angioplasty. The angiographic result was suboptimal, nevertheless, the graft function improved and was more or less stable (serum creatinine, 160-200 {mu}mol/l) for 4 years, along with persistently difficult-to-control hypertension. Five years after transplantation, the graft function deteriorated again and severe graftmore » artery restenosis was detected. The restenosis did not respond to dilatation, graft function failed, hypertension decompensated, and left ventricular failure developed. The patient required dialysis. A cutting balloon angioplasty opened the artery, and kidney function was restored after a few days: the serum creatinine level dropped to 140-160 {mu}mol/l, and the glomerular filtration rate (creatinine clearance) to 0.65 ml/min/1.73 m{sup 2}. The graft function has now been stable for more than 2 years, however, the hypertension is still difficult to control.« less

Effect of dark chocolate on arterial function in healthy individuals: cocoa instead of ambrosia?

PubMed

Vlachopoulos, Charalambos; Alexopoulos, Nikolaos; Stefanadis, Christodoulos

2006-06-01

Cocoa has been consumed for at least 2500 years, and for long time it has been regarded as a medicine. Arterial function is of paramount importance for the proper function and integrity of the cardiovascular system. Dark chocolate and flavonoid-rich cocoa have beneficial acute and short-term effects on endothelial function and wave reflections in normal individuals, in adults with cardiovascular risk factors, and in patients with coronary artery disease. Furthermore, dark chocolate and flavonoid-rich cocoa may have a blood pressure-lowering effect. These effects can be attributed to flavonoids and are mainly mediated through increased nitric oxide bioavailability. Further research is needed to demonstrate whether these effects of chocolate on arterial function are translated into clinical benefit.

Transfer function analysis of dynamic cerebral autoregulation in humans

NASA Technical Reports Server (NTRS)

Zhang, R.; Zuckerman, J. H.; Giller, C. A.; Levine, B. D.; Blomqvist, C. G. (Principal Investigator)

1998-01-01

To test the hypothesis that spontaneous changes in cerebral blood flow are primarily induced by changes in arterial pressure and that cerebral autoregulation is a frequency-dependent phenomenon, we measured mean arterial pressure in the finger and mean blood flow velocity in the middle cerebral artery (VMCA) during supine rest and acute hypotension induced by thigh cuff deflation in 10 healthy subjects. Transfer function gain, phase, and coherence function between changes in arterial pressure and VMCA were estimated using the Welch method. The impulse response function, calculated as the inverse Fourier transform of this transfer function, enabled the calculation of transient changes in VMCA during acute hypotension, which was compared with the directly measured change in VMCA during thigh cuff deflation. Beat-to-beat changes in VMCA occurred simultaneously with changes in arterial pressure, and the autospectrum of VMCA showed characteristics similar to arterial pressure. Transfer gain increased substantially with increasing frequency from 0.07 to 0.20 Hz in association with a gradual decrease in phase. The coherence function was > 0.5 in the frequency range of 0.07-0.30 Hz and < 0.5 at < 0.07 Hz. Furthermore, the predicted change in VMCA was similar to the measured VMCA during thigh cuff deflation. These data suggest that spontaneous changes in VMCA that occur at the frequency range of 0.07-0.30 Hz are related strongly to changes in arterial pressure and, furthermore, that short-term regulation of cerebral blood flow in response to changes in arterial pressure can be modeled by a transfer function with the quality of a high-pass filter in the frequency range of 0.07-0.30 Hz.

Pseudomonas aeruginosa Microcolonies in Coronary Thrombi from Patients with ST-Segment Elevation Myocardial Infarction

PubMed Central

Hansen, Gorm Mørk; Belstrøm, Daniel; Nilsson, Martin; Helqvist, Steffen; Nielsen, Claus Henrik; Holmstrup, Palle; Tolker-Nielsen, Tim; Givskov, Michael; Hansen, Peter Riis

2016-01-01

Chronic infection is associated with an increased risk of atherothrombotic disease and direct bacterial infection of arteries has been suggested to contribute to the development of unstable atherosclerotic plaques. In this study, we examined coronary thrombi obtained in vivo from patients with ST-segment elevation myocardial infarction (STEMI) for the presence of bacterial DNA and bacteria. Aspirated coronary thrombi from 22 patients with STEMI were collected during primary percutaneous coronary intervention and arterial blood control samples were drawn from radial or femoral artery sheaths. Analyses were performed using 16S polymerase chain reaction and with next-generation sequencing to determine bacterial taxonomic classification. In selected thrombi with the highest relative abundance of Pseudomonas aeruginosa DNA, peptide nucleic acid fluorescence in situ hybridization (PNA-FISH) with universal and species specific probes was performed to visualize bacteria within thrombi. From the taxonomic analysis we identified a total of 55 different bacterial species. DNA from Pseudomonas aeruginosa represented the only species that was significantly associated with either thrombi or blood and was >30 times more abundant in thrombi than in arterial blood (p<0.0001). Whole and intact bacteria present as biofilm microcolonies were detected in selected thrombi using universal and P. aeruginosa-specific PNA-FISH probes. P. aeruginosa and vascular biofilm infection in culprit lesions may play a role in STEMI, but causal relationships remain to be determined. PMID:28030624

Intramedullary reduction and stabilisation of adult radial neck fractures.

PubMed

Keller, H W; Rehm, K E; Helling, J

1994-05-01

We report the treatment of six adult patients with displaced fractures of the radial neck by intramedullary reduction and stabilisation. Nine months after operation all the patients had good joint function, little or no pain, complete healing and no significant periarticular calcification. This simple semi-closed procedure may help to avoid resection of the radial head in some cases.

A curve-fitting approach to estimate the arterial plasma input function for the assessment of glucose metabolic rate and response to treatment.

PubMed

Vriens, Dennis; de Geus-Oei, Lioe-Fee; Oyen, Wim J G; Visser, Eric P

2009-12-01

For the quantification of dynamic (18)F-FDG PET studies, the arterial plasma time-activity concentration curve (APTAC) needs to be available. This can be obtained using serial sampling of arterial blood or an image-derived input function (IDIF). Arterial sampling is invasive and often not feasible in practice; IDIFs are biased because of partial-volume effects and cannot be used when no large arterial blood pool is in the field of view. We propose a mathematic function, consisting of an initial linear rising activity concentration followed by a triexponential decay, to describe the APTAC. This function was fitted to 80 oncologic patients and verified for 40 different oncologic patients by area-under-the-curve (AUC) comparison, Patlak glucose metabolic rate (MR(glc)) estimation, and therapy response monitoring (Delta MR(glc)). The proposed function was compared with the gold standard (serial arterial sampling) and the IDIF. To determine the free parameters of the function, plasma time-activity curves based on arterial samples in 80 patients were fitted after normalization for administered activity (AA) and initial distribution volume (iDV) of (18)F-FDG. The medians of these free parameters were used for the model. In 40 other patients (20 baseline and 20 follow-up dynamic (18)F-FDG PET scans), this model was validated. The population-based curve, individually calibrated by AA and iDV (APTAC(AA/iDV)), by 1 late arterial sample (APTAC(1 sample)), and by the individual IDIF (APTAC(IDIF)), was compared with the gold standard of serial arterial sampling (APTAC(sampled)) using the AUC. Additionally, these 3 methods of APTAC determination were evaluated with Patlak MR(glc) estimation and with Delta MR(glc) for therapy effects using serial sampling as the gold standard. Excellent individual fits to the function were derived with significantly different decay constants (P < 0.001). Correlations between AUC from APTAC(AA/iDV), APTAC(1 sample), and APTAC(IDIF) with the gold standard (APTAC(sampled)) were 0.880, 0.994, and 0.856, respectively. For MR(glc), these correlations were 0.963, 0.994, and 0.966, respectively. In response monitoring, these correlations were 0.947, 0.982, and 0.949, respectively. Additional scaling by 1 late arterial sample showed a significant improvement (P < 0.001). The fitted input function calibrated for AA and iDV performed similarly to IDIF. Performance improved significantly using 1 late arterial sample. The proposed model can be used when an IDIF is not available or when serial arterial sampling is not feasible.

Evaluation of a static stretching intervention on vascular endothelial function and arterial stiffness.

PubMed

Shinno, Hiromi; Kurose, Satoshi; Yamanaka, Yutaka; Higurashi, Kyoko; Fukushima, Yaeko; Tsutsumi, Hiromi; Kimura, Yutaka

2017-06-01

Maintenance and enhancement of vascular endothelial function contribute to the prevention of cardiovascular disease and prolong a healthy life expectancy. Given the reversible nature of vascular endothelial function, interventions to improve this function might prevent arteriosclerosis. Accordingly, we studied the effects of a 6-month static stretching intervention on vascular endothelial function (reactive hyperaemia peripheral arterial tonometry index: RH-PAT index) and arterial stiffness (brachial-ankle pulse wave velocity: baPWV) and investigated the reversibility of these effects after a 6-month detraining period following intervention completion. The study evaluated 22 healthy, non-smoking, premenopausal women aged ≥40 years. Subjects were randomly assigned to the full-intervention (n = 11; mean age: 48.6 ± 2.8 years) or a half-intervention that included a control period (n = 11; mean age: 46.9 ± 3.6 years). Body flexibility and vascular endothelial function improved significantly after 3 months of static stretching. In addition to these improvements, arterial stiffness improved significantly after a 6-month intervention. However, after a 6-month detraining period, vascular endothelial function, flexibility, and arterial stiffness all returned to preintervention conditions, demonstrating the reversibility of the obtained effects. A 3-month static stretching intervention was found to improve vascular endothelial function, and an additional 3-month intervention also improved arterial stiffness. However, these effects were reversed by detraining.

Evaluation of Transient Motion During Gadoxetic Acid-Enhanced Multiphasic Liver Magnetic Resonance Imaging Using Free-Breathing Golden-Angle Radial Sparse Parallel Magnetic Resonance Imaging.

PubMed

Yoon, Jeong Hee; Lee, Jeong Min; Yu, Mi Hye; Hur, Bo Yun; Grimm, Robert; Block, Kai Tobias; Chandarana, Hersh; Kiefer, Berthold; Son, Yohan

2018-01-01

The aims of this study were to observe the pattern of transient motion after gadoxetic acid administration including incidence, onset, and duration, and to evaluate the clinical feasibility of free-breathing gadoxetic acid-enhanced liver magnetic resonance imaging using golden-angle radial sparse parallel (GRASP) imaging with respiratory gating. In this institutional review board-approved prospective study, 59 patients who provided informed consents were analyzed. Free-breathing dynamic T1-weighted images (T1WIs) were obtained using GRASP at 3 T after a standard dose of gadoxetic acid (0.025 mmol/kg) administration at a rate of 1 mL/s, and development of transient motion was monitored, which is defined as a distinctive respiratory frequency alteration of the self-gating MR signals. Early arterial, late arterial, and portal venous phases retrospectively reconstructed with and without respiratory gating and with different temporal resolutions (nongated 13.3-second, gated 13.3-second, gated 6-second T1WI) were evaluated for image quality and motion artifacts. Diagnostic performance in detecting focal liver lesions was compared among the 3 data sets. Transient motion (mean duration, 21.5 ± 13.0 seconds) was observed in 40.0% (23/59) of patients, 73.9% (17/23) of which developed within 15 seconds after gadoxetic acid administration. On late arterial phase, motion artifacts were significantly reduced on gated 13.3-second and 6-second T1WI (3.64 ± 0.34, 3.61 ± 0.36, respectively), compared with nongated 13.3-second T1WI (3.12 ± 0.51, P < 0.0001). Overall, image quality was the highest on gated 13.3-second T1WI (3.76 ± 0.39) followed by gated 6-second and nongated 13.3-second T1WI (3.39 ± 0.55, 2.57 ± 0.57, P < 0.0001). Only gated 6-second T1WI showed significantly higher detection performance than nongated 13.3-second T1WI (figure of merit, 0.69 [0.63-0.76]) vs 0.60 [0.56-0.65], P = 0.004). Transient motion developed in 40% (23/59) of patients shortly after gadoxetic acid administration, and gated free-breathing T1WI using GRASP was able to consistently provide acceptable arterial phase imaging in patients who exhibited transient motion.

Compartment Syndrome of the Hand: A Rare Sequela of Transradial Cardiac Catheterization

PubMed Central

Jue, Jennifer; Karam, Joseph A.; Mejia, Alfonso

2017-01-01

A 64-year-old man who underwent percutaneous coronary intervention via right radial artery access reported right-hand pain and swelling 2 hours after the procedure. He had developed compartment syndrome of the hand, specifically with muscular compromise of the thenar compartment but with no involvement of the forearm. He underwent emergency right-hand compartment release and carpal tunnel release, followed by an uneventful postoperative course. In addition to our patient's case, we discuss compartment syndrome of the hand and related issues. PMID:28265219

The late open infarct-related artery hypothesis: evidence-based medicine or not?

PubMed

Brueck, Martin; Bandorski, Dirk; Kramer, Wilfried; Vogt, Paul R; Heidt, Martin C

2007-11-01

Randomized clinical trials have clearly shown that early reperfusion of coronary arteries is the established treatment of myocardial infarction preserving left ventricular function and reducing mortality. However, late patency of the infarct-related artery is an independent predictor of survival leading to the late open-artery hypothesis. This concept implies restoration of antegrade blood flow of the infarct-related artery in patients with myocardial infarction to improve survival by mechanisms less time-dependent or even time-independent. Possible explanations for this benefit include improved left ventricular function and electrical stability by perfusion of hibernating myocardium, accelerated infarct healing and limitation of ventricular remodeling. This review focuses on the evidence of late recanalization of occluded infarct-related arteries in patients with coronary artery disease.

On-top and side-to-side plasties for thumb polydactyly.

PubMed

Al-Qattan, Noha M; Al-Qattan, Mohammad M

2017-01-01

"On-top" and "side-to-side" plasties are techniques used for treating thumb duplications in which one thumb is adequate proximally and the other thumb contains a better pulp and nail distally. The detailed functional results of these techniques have not been reported in the literature. We report on two cases. The first case had Wassel type VI duplication. The ulnar duplicate had a functioning interphalangeal joint and the radial duplicate had a functioning carpometacarpal joint. "On-top" plasty was done by putting the distal part of the ulnar duplicate on top of the proximal part of the radial duplicate. At 10 years after surgery, the outcome was excellent both cosmetically and functionally. In the second case (Wassel type VII with a zigzag deformity), the radial duplicate had a hypoplastic distal phalanx with no nail. The ulnar duplicate had a functioning interphalangeal joint and the radial duplicate had a functioning carpometacarpal joint. "Side-to-side" plasty was done by joining both thumbs side-to-side at the level of the proximal phalanx. At 3 years after surgery, the outcome we considered acceptable cosmetically and excellent functionally. We could not find similar cases in the literature with detailed long-term postoperative results. "On-top" and "side-to-side" plasties in the management of specific cases of thumb polydactyly obtain excellent functional results with excellent or acceptable cosmetic outcome. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

SU-F-18C-11: Diameter Dependency of the Radial Dose Distribution in a Long Polyethylene Cylinder

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bakalyar, D; McKenney, S; Feng, W

Purpose: The radial dose distribution in the central plane of a long cylinder following a long CT scan depends upon the diameter and composition of the cylinder. An understanding of this behavior is required for determining the spatial average of the dose in the central plane. Polyethylene, the material for construction of the TG200/ICRU phantom (30 cm in diameter) was used for this study. Size effects are germane to the principles incorporated in size specific dose estimates (SSDE); thus diameter dependency was explored as well. Method: ssuming a uniform cylinder and cylindrically symmetric conditions of irradiation, the dose distribution canmore » be described using a radial function. This function must be an even function of the radial distance due to the conditions of symmetry. Two effects are accounted for: The direct beam makes its weakest contribution at the center while the contribution due to scatter is strongest at the center and drops off abruptly at the outer radius. An analytic function incorporating these features was fit to Monte Carlo results determined for infinite polyethylene cylinders of various diameters. A further feature of this function is that it is integrable. Results: Symmetry and continuity dictate a local extremum at the center which is a minimum for the larger sizes. The competing effects described above can Resultin an absolute maximum occurring between the center and outer edge of the cylinders. For the smallest cylinders, the maximum dose may occur at the center. Conclusion: An integrable, analytic function can be used to characterize the radial dependency of dose for cylindrical CT phantoms of various sizes. One use for this is to help determine average dose distribution over the central cylinder plane when equilibrium dose has been reached.« less

Radial hemostasis is facilitated with a potassium ferrate hemostatic patch: the Statseal with TR band assessment trial (STAT).

PubMed

Seto, Arnold H; Rollefson, William; Patel, Mitul P; Suh, William M; Tehrani, David M; Nguyen, Jacqueline A; Amador, Daniel G; Behnamfar, Omid; Garg, Vinisha; Cohen, Mauricio G

2018-05-15

Hemostasis is a limiting factor for discharge after uncomplicated transradial procedures. The potassium ferrate hemostatic patch (PFHP) may serve as an adjunct to the air-bladder TR band (TRB) and allow expedited deflation of the TRB. Prospective multicenter randomized controlled trial comparing radial hemostatic protocols. Deflation of the TRB was attempted at 40 minutes with PFHP and at 120 minutes without the PFHP. The primary outcome was time to full deflation of the TRB with hemostasis. At four U.S. sites, 180 patients were enrolled after receiving a minimum of 5,000 units of unfractionated heparin or bivalirudin. Interventions comprised 30% of procedures. Successful TRB deflation occurred at 43 ± 14 minutes with PFHP and 160 ± 43 minutes without PFHP (p<0.001). Minor hematomas occurred in 9 (10.3%) of TRB patients and 16 (17.2%) of PFHP patients (p=0.20). Radial artery occlusion occurred in 2% of patients in the PFHP group (p=NS). Outpatients randomized to PFHP were discharged 51 ± 83.5 minutes earlier than control. The PFHP hemostatic patch facilitated early deflation of the TRB with a nonsignificant increase in forearm hematomas. Use of the PFHP may improve patient throughput and allow for earlier discharge following transradial procedures.

Alteration of Left Ventricular Function with Dobutamine Challenge in Patients with Myocardial Bridge

PubMed Central

Jhi, Joon-Hyung; Ha, Jong-kun; Jung, Chan-Woo; kim, Bong-Jae; Park, Seong-Oh; Jo, A-Ra; Kim, Seong-Man; Lee, Hyeon-Gook; Kim, Tae-Ik

2011-01-01

Background/Aims The aim of this study was to identify changes in left ventricular (LV) performance in patients with a myocardial bridge (MB) in the left anterior descending coronary artery during resting and in an inotropic state. Methods Myocardial strain measurement by speckle-tracking echocardiography and conventional LV wall-motion scoring was performed in 18 patients with MB (mean age, 48.1 ± 1.7 years, eight female) during resting and intravenous dobutamine challenge (10 and 20 µg/kg/min). Results Conventional LV wall-motion scoring was normal in all patients during resting and in an inotropic state. Peak regional circumferential strain increased dose dependently upon dobutamine challenge. Longitudinal strains of the anterior and anteroseptal segments were, however, reduced at 20 µg/kg/min and showed a dyssynchronous pattern at 20 µg/kg/min. Although there were no significant differences in radial strain and displacement of all segments at rest compared with under 10 µg/kg/min challenge, radial strain and displacement of anterior segments at 20 µg/kg/min were significantly reduced compared with posterior segments at the papillary muscle level (44.8 ± 14.9% vs. 78.4 ± 20.1% and 5.3 ± 2.3 mm vs. 8.5 ± 1.8 mm, respectively; all p < 0.001), and showed plateau (40%) or biphasic (62%) patterns. Conclusions Reduced LV strain of patients with MB after inotropic stimulation was identified. Speckle-tracking strain echocardiography identified a LV myocardial dyssynchrony that was not demonstrated by conventional echocardiography in patients with MB. PMID:22205841

[Application of continuous intra-arterial blood gas monitoring system "Paratrend 7" for pulmonary lavage of a patient with alveolar proteinosis].

PubMed

Harigae, M; Hirose, Y; Gamo, M; Hirose, M; Fujiwara, C; Matsuo, K

1999-03-01

We applied a continuous intra-arterial blood gas monitoring system (Paratrend 7) to a patient with pulmonary alveolar proteinosis during pulmonary lavage. Lavage was performed under general anesthesia with one lung ventilation. We inserted the sensor of Patatrend 7 through a 20 G catheter into the radial artery, and monitored pH, PaCO2 and PaO2 continuously throughout the procedure. SpO2 and EtCO2 were also monitored. Saline 1000-1500 ml was instilled and drained repeatedly by volume limited methods. PaO2 values by Paratrend 7 increased during instillation and decreased during drainage of the irrigating fluid. In contrast, PaCO2 value by Paratrend 7 decreased slightly during instillation and increased during drainage. The change of SpO2 was almost the same as that by Paratrend 7, but the response time of pulse oxymetry was a little quicker than Paratrend 7. During the lavage procedure, respiratory and circulatory condition changed very rapidly, and it is necessary to monitor blood gas change intensively. Paratrend 7 is useful as a perioperative monitoring system, but pulse oxymetry might be sufficient during pulmonary lavage considering its cost.

Relationships among the serum omega fatty acid levels, serum C-reactive protein levels and arterial stiffness/wave reflection in Japanese men.

PubMed

Tomiyama, Hirofumi; Matsumoto, Chisa; Odaira, Mari; Yamada, Jiko; Yoshida, Masanobu; Shiina, Kazuki; Nagata, Mikio; Yamashina, Akira

2011-08-01

We examined the relationship among the serum omega-3 and omega-6 fatty acid (O3FA and O6FA) levels, serum C-reactive protein (CRP) levels, and arterial stiffness/wave reflection (AS/WR) in healthy Japanese men. In 2206 Japanese healthy men, parameters related to the AS/WR (i.e., brachial-ankle pulse wave velocity and radial arterial pulse wave analysis) were measured. No significant inverse relationships were observed between the serum O3FA levels and the AS/WR-related parameters. Adjusted values of the AS/WR-related parameters and serum CRP levels were higher in the subjects with serum O6FA levels in the highest tertile than in those with serum O6FA levels in the lowest tertile. In healthy Japanese men with known high dietary intakes of O3FAs, the serum O3FA levels may not reflect the pathophysiological abnormalities related to AS/WR. Increased serum O6FA levels appeared to be independently associated with the unfavorable conditions related to AS/WR and inflammation. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Blood flow velocity measurement by endovascular Doppler optical coherence tomography

NASA Astrophysics Data System (ADS)

Sun, Cuiru; Nolte, Felix; Vuong, Barry; Cheng, Kyle H. Y.; Lee, Kenneth K. C.; Standish, Beau A.; Courtney, Brian; Marotta, Tom R.; Yang, Victor X. D.

2013-03-01

Blood flow velocity and volumetric flow measurements are important parameters for assessment of the severity of stenosis and the outcome of interventional therapy. However, feasibility of intravascular flow measurement using a rotational catheter based phase resolved Doppler optical coherence tomography (DOCT) is difficult. Motion artefacts induced by the rotating optical imaging catheter, and the radially dependent noise background of measured Doppler signals are the main challenges encountered. In this study, a custom-made data acquisition system and developed algorithms to remove non-uniform rotational distortion (NURD) induced phase shift artefact by tracking the phase shift observed on catheter sheath. The flow velocity is calculated from Doppler shift obtained by Kasai autocorrelation after motion artefact removal. Blood flow velocity profiles in porcine carotid arteries in vivo were obtained at 100 frames/s with 500 A-lines/frame and DOCT images were taken at 20 frames/s with 2500 A-lines/frame. Time-varying velocity profiles were obtained at an artery branch. Furthermore, the identification of a vein adjacent to the catheterized vessel based on the color Doppler signal was also observed. The absolute measurement of intravascular flow using a rotating fiber catheter can provide insights to different stages of interventional treatment of stenosis in carotid artery.

Classification of Phylogenetic Profiles for Protein Function Prediction: An SVM Approach

NASA Astrophysics Data System (ADS)

Kotaru, Appala Raju; Joshi, Ramesh C.

Predicting the function of an uncharacterized protein is a major challenge in post-genomic era due to problems complexity and scale. Having knowledge of protein function is a crucial link in the development of new drugs, better crops, and even the development of biochemicals such as biofuels. Recently numerous high-throughput experimental procedures have been invented to investigate the mechanisms leading to the accomplishment of a protein’s function and Phylogenetic profile is one of them. Phylogenetic profile is a way of representing a protein which encodes evolutionary history of proteins. In this paper we proposed a method for classification of phylogenetic profiles using supervised machine learning method, support vector machine classification along with radial basis function as kernel for identifying functionally linked proteins. We experimentally evaluated the performance of the classifier with the linear kernel, polynomial kernel and compared the results with the existing tree kernel. In our study we have used proteins of the budding yeast saccharomyces cerevisiae genome. We generated the phylogenetic profiles of 2465 yeast genes and for our study we used the functional annotations that are available in the MIPS database. Our experiments show that the performance of the radial basis kernel is similar to polynomial kernel is some functional classes together are better than linear, tree kernel and over all radial basis kernel outperformed the polynomial kernel, linear kernel and tree kernel. In analyzing these results we show that it will be feasible to make use of SVM classifier with radial basis function as kernel to predict the gene functionality using phylogenetic profiles.

SU-E-T-259: Particle Swarm Optimization in Radial Dose Function Fitting for a Novel Iodine-125 Seed

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wu, X; Duan, J; Popple, R

2014-06-01

Purpose: To determine the coefficients of bi- and tri-exponential functions for the best fit of radial dose functions of the new iodine brachytherapy source: Iodine-125 Seed AgX-100. Methods: The particle swarm optimization (PSO) method was used to search for the coefficients of the biand tri-exponential functions that yield the best fit to data published for a few selected radial distances from the source. The coefficients were encoded into particles, and these particles move through the search space by following their local and global best-known positions. In each generation, particles were evaluated through their fitness function and their positions were changedmore » through their velocities. This procedure was repeated until the convergence criterion was met or the maximum generation was reached. All best particles were found in less than 1,500 generations. Results: For the I-125 seed AgX-100 considered as a point source, the maximum deviation from the published data is less than 2.9% for bi-exponential fitting function and 0.2% for tri-exponential fitting function. For its line source, the maximum deviation is less than 1.1% for bi-exponential fitting function and 0.08% for tri-exponential fitting function. Conclusion: PSO is a powerful method in searching coefficients for bi-exponential and tri-exponential fitting functions. The bi- and tri-exponential models of Iodine-125 seed AgX-100 point and line sources obtained with PSO optimization provide accurate analytical forms of the radial dose function. The tri-exponential fitting function is more accurate than the bi-exponential function.« less

Effect of Aggressive lipid-lowering treatment with Rosuvastatin on vascular endoTHelium function: evaluation of vascular endothelium function (EARTH study).

PubMed

Takayama, Tadateru; Hiro, Takafumi; Yoda, Shunichi; Fukamachi, Daisuke; Haruta, Hironori; Kogo, Takaaki; Mineki, Takashi; Murata, Hironobu; Oshima, Toru; Hirayama, Atsushi

2018-06-01

Vascular endothelial dysfunction plays an important role in the process of atherosclerosis up to the final stage of plaque rupture. Vascular endothelial dysfunction is reversible, and can be recovered by medications and life-style changes. Improvement in endothelial function may reduce cardiovascular events and improve long-term prognosis. A total of 50 patients with stable angina and dyslipidemia were enrolled, including patients who had not received prior treatment with statins and had serum LDL-C levels ≥ 100 mg/dL, and patients who had previously received statin treatment. All agreed to register regardless of their LDL-C level. Rosuvastatin was initially administered at a dose of 2.5 mg and appropriately titrated up to the maximum dose of 20 mg or until LDL-C levels lower than 80 mg/dL were achieved, for 24 weeks. Endothelial function was assessed by the reactive hyperemia peripheral arterial tonometry (RH-PAT) index in the radial artery by Endo-PAT ® 2000 (Endo-PAT ® 2000, software version 3.0.4, Itamar Medical Ltd., Caesarea, Israel). RH-PAT data were digitally analyzed online by Endo-PAT ® 2000 at baseline and at 24 weeks. LDL-C and MDA-LDL-C decreased from 112.6 ± 23.3 to 85.5 ± 20.2 mg/dL and from 135.1 ± 36.4 to 113.9 ± 23.5 mg/dL respectively (p < 0.0001). However, HDL-C, hs-CRP and TG did not change significantly after treatment. RH-PAT index levels significantly improved, from 1.60 ± 0.31 to 1.77 ± 0.57 (p = 0.04) after treatment, and the percent change of the RH-PAT index was 12.8 ± 36.9%. Results of multivariate analysis show that serum LDL-C levels over 24 weeks did not act as a predictor of improvement of the RH-PAT index. However, HbA1c at baseline was an independent predictor which influenced the 24-week RH-PAT index level. The RH-PAT index of patients with high HbA1c at baseline did not improve after administration of rosuvastatin but it did improve in patients with low HbA1c at baseline. Aggressive lowering of LDL-C with rosuvastatin significantly improved the RH-PAT index, suggesting that it may improve endothelial function in patients with coronary artery disease.Clinical Trial Registration No: UMIN-CTR, UMIN000010040.

A well-balanced meshless tsunami propagation and inundation model

NASA Astrophysics Data System (ADS)

Brecht, Rüdiger; Bihlo, Alexander; MacLachlan, Scott; Behrens, Jörn

2018-05-01

We present a novel meshless tsunami propagation and inundation model. We discretize the nonlinear shallow-water equations using a well-balanced scheme relying on radial basis function based finite differences. For the inundation model, radial basis functions are used to extrapolate the dry region from nearby wet points. Numerical results against standard one- and two-dimensional benchmarks are presented.