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1

Sensitivity and specificity of frequently used electrocardiographic criteria for left ventricular hypertrophy in patients with anterior wall myocardial infarction  

PubMed Central

Electrocardiographic left ventricular hypertrophy (LVH) strongly predicts mortality in patients with myocardial infarction (MI). However, the validity of LVH voltage criteria in this context has not been assessed. Reviewing the coded database of echocardiographic studies performed at one institution, we performed a retrospective analysis of 49 patients who had anterior akinesis on the echocardiogram and anterior wall MI on the electrocardiogram. Results showed that, compared with the sensitivities and specificities of the electrocardiographic voltage criteria in historical cohorts, Cornell criteria were less sensitive and specific for the diagnosis of LVH in patients with anterior wall MI. The sensitivity was reduced in the presence of an associated lateral wall MI, and the specificity was reduced in the absence of a lateral wall MI (overall sensitivity in case of anterior wall MI, with or without an associated lateral wall MI, 21% vs 41%, P = 0.049; overall specificity 84% vs 98%, P = 0.003). All criteria, except for S in V1 + R in V5 or V6 >3.5 mV, had a significantly reduced specificity in the case of anterior wall MI not associated with lateral wall MI, and all criteria, except for R in V6 > R in V5, had reduced sensitivity in the presence of a lateral wall MI. In conclusion, anterior wall MI reduces the sensitivity and the specificity of the most commonly used LVH voltage criteria. PMID:20157497

Glancy, D. Luke; Oral, Evrim

2010-01-01

2

Spectrum and significance of electrocardiographic patterns, troponin levels, and thrombolysis in myocardial infarction frame count in patients with stress (tako-tsubo) cardiomyopathy and comparison to those in patients with ST-elevation anterior wall myocardial infarction.  

PubMed

Stress (takotsubo) cardiomyopathy (SC) is a recently recognized syndrome with clinical and electrocardiographic (ECG) presentation resembling ST elevation anterior myocardial infarction. As experience with this condition has evolved, a more diverse spectrum of 12-lead ECG patterns has emerged that may affect differential diagnosis. Fifty-nine consecutive patients with SC were prospectively identified at a large community-based cardiology practice. All were women aged 32 to 90 years (mean 66+/-13) with acute chest pain triggered by emotional or physical incidents and with akinesia of the mid-distal left ventricle; each patient recovered and was discharged within a median of 4 days. On electrocardiography, anterior ST elevation was most common (33 [56%]), with magnitudes less than in controls with left anterior descending coronary artery occlusions (1.4+/-1.5 vs 2.4+/-2.2 mm, p<0.001), with considerable overlap. ECG findings in 26 other patients (44%) without ST elevation revealed diffuse T-wave inversion (10 [17%]) and healed anterior infarctions (6 [10%]) or were nonspecific (5 [8.5%]) or normal (5 [8.5%]). Troponin elevations occurred in 56 patients with SC (95%). The mean peak troponin T level was significantly lower in patients with SC (0.64+/-0.86 ng/ml) than in those with left anterior descending coronary artery occlusions (3.88+/-4.9 ng/ml) (p<0.0001). Patients with SC with or without ST elevation did not differ with respect to the ejection fraction (29+/-9% vs 34+/-9%, respectively, p=NS) or Thrombolysis In Myocardial Infarction (TIMI) frame counts. During recovery, diffuse T-wave inversion evolved in 49 patients with SC (83%). In conclusion, patients with SC present with diverse ECG findings, and no single pattern alone can reliably distinguish this condition from acute coronary syndromes. The diagnosis of SC requires heightened awareness of its unique clinical profile as well as coronary arteriography and left ventriculography. PMID:18549847

Sharkey, Scott W; Lesser, John R; Menon, Madhav; Parpart, Mary; Maron, Martin S; Maron, Barry J

2008-06-15

3

Early results of a novel technique for anterior vaginal wall prolapse repair: anterior vaginal wall darn  

PubMed Central

Background The aim of this study was to describe the results of a 1-year patient follow-up after anterior vaginal wall darn, a novel technique for the repair of anterior vaginal wall prolapse. Methods Fifty-five patients with anterior vaginal wall prolapse underwent anterior vaginal wall darn. The anterior vaginal wall was detached using sharp and blunt dissection via an incision beginning 1 cm proximal to the external meatus and extending to the vaginal apex. The space between the tissues that attach the lateral vaginal walls to the arcus tendineus fasciae pelvis was then darned. Cough Stress Test, Pelvic Organ Prolapse Quantification, seven-item Incontinence Impact Questionnaire, and six-item Urogenital Distress Inventory scores were performed 1-year postoperatively to evaluate recovery. Results One-year postoperatively, all patients were satisfied with the results of the procedure. No patient had vaginal mucosal erosion or any other complication. Conclusions One-year postoperative findings for patients in this series indicate that patients with stage II–III anterior vaginal wall prolapse were successfully treated with the anterior vaginal wall darn technique. PMID:24973955

2014-01-01

4

A new ECG criterion to identify takotsubo cardiomyopathy from anterior myocardial infarction: role of inferior leads  

Microsoft Academic Search

With the exception of contrast-enhanced cardiovascular magnetic resonance imaging, clear distinction of takotsubo cardiomyopathy\\u000a from anterior wall myocardial infarction cannot be achieved currently by simple and noninvasive tests. The aim of this study\\u000a was to examine the role of inferior ECG leads in distinguishing these two conditions. From January 2004 to June 2006, eight\\u000a female patients suffering from takotsubo cardiomyopathy

Man-Hong Jim; Annie On-On Chan; Ping-Tim Tsui; Suet-Ting Lau; Chung-Wah Siu; Wing-Hing Chow; Chu-Pak Lau

2009-01-01

5

Imaging electrical excitation inside the myocardial wall  

PubMed Central

Cardiac arrhythmias are often triggered by ectopic membrane depolarization originating deep inside the myocardial wall. Here we propose a new method utilizing a novel near-infrared voltage-sensitive fluorescent dye DI-4-ANBDQBS to determine the three-dimensional (3D) coordinates of the sources of such depolarization. We tested the method in live preparations of pig left and right ventricular myocardium (thickness 8-18 mm) and phantoms imitating the optical properties of myocardial tissue. The method utilizes an alternating transillumination approach that involves comparing pairs of simultaneously recorded broad-field epifluorescence and transillumination images produced at two alternating directions of illumination. Recordings were taken simultaneously by two CCD cameras facing the endocardial and epicardial surfaces of the heart at a frame rate up to 3 KHz. In live preparations, we were able to localize the origin of the depolarization wave with a precision of ±1.3mm in the transmural direction and 3 mm in the image plane. The accuracy of detection was independent of the depth of the source inside ventricular wall. PMID:21412467

Mitrea, Bogdan G; Caldwell, Bryan J; Pertsov, Arkady M

2011-01-01

6

Anterior ST segment depression in acute inferior myocardial infarction as a marker of greater inferior, apical, and posterolateral damage  

SciTech Connect

The clinical significance of anterior precordial ST segment depression during acute inferior myocardial infarction was evaluated in 67 consecutive patients early after onset of symptoms with gated blood pool scans, thallium-201 perfusion images, and 12-lead ECGs. Patients with anterior ST depression (n = 33) had depressed mean values for left ventricular ejection fraction (54 +/- 2% (mean +/- S.E.M.) vs 59 +/- 2%; p = 0.02), cardiac index (3.1 +/- 0.2 vs 3.6 +/- 0.2 L/m2; p = 0.03), and ratio of systolic blood pressure to end-systolic volume (2.0 +/- 0.1 vs 2.5 +/- 0.3 mm Hg/ml; p = 0.04) compared to patients with no anterior ST depression (n = 34). Patients with anterior ST depression had (1) lower mean wall motion values for the inferior, apical, and inferior posterolateral segments (p less than 0.05) and (2) greater reductions in thallium-201 uptake in the inferior and posterolateral regions (p less than 0.05). However, anterior and septal (1) wall motion and (2) thallium-201 uptake were similar in patients with and without ST depression. Thus, anterior precordial ST segment depression in patients with acute inferior wall myocardial infarction represents more than a reciprocal electrical phenomenon. It identifies patients with more severe wall motion impairment and greater hypoperfusion of the inferior and adjacent segments. The poorer global left ventricular function in these patients is a result of more extensive inferior infarction and not of remote septal or anterior injury.

Ruddy, T.D.; Yasuda, T.; Gold, H.K.; Leinbach, R.C.; Newell, J.B.; McKusick, K.A.; Boucher, C.A.; Strauss, H.W.

1986-12-01

7

Anterior sagittal approach without splitting the rectal wall  

PubMed Central

INTRODUCTION The anterior sagittal transrectal approach (ASTRA) has already become popular to treat lesions in the proximal urethra such as trauma, duplicity and stenosis, prostatic utricle, urethral–vaginal fistulas and urogenital sinus anomalies. It provides much better exposure than the traditional perineal approach. Morbidity caused by this technique could be potentially decreased if the anterior sagittal access were to be made without sectioning the rectum. We report our initial experience using anterior approach without rectal sectioning for the treatment of three different types of pelvic disorders. PRESENTATION OF CASE Anterior sagittal access without sectioning the rectal wall was carried out in three different clinical cases – a vaginoplasty in a female patient with congenital adrenal hyperplasia; to treat paradoxical urinary incontinence in a patient with proximal hypospadias (46XY karyotype) and another one with gonadal dysgenesis (46XO/XY karyotype). DISCUSSION Several surgical techniques have been reported to repair congenital or acquired lesions in the posterior urethra with high morbidity and no guarantees of adequate and safe surgical exposition. ASTRA provides an excellent exposure, splitting only the anterior rectal wall. In this study, the anterior sagittal approach was applied without splitting the rectal wall to repair different posterior urethral anomalies, providing excellent exposure without compromising the fecal continence mechanism. CONCLUSION The anterior sagittal approach without splitting the rectum is a feasible procedure which provides excellent exposure to the posterior urethra in most cases and leads to less morbidity as it avoids the splitting and suturing of the rectum anterior wall. PMID:23811390

Leite, Mila Torii Correa; Fachin, Camila Girardi; de Albuquerque Maranhao, Renato Frota; Shida, Marcia Emilia Francisco; Martins, Jose Luiz

2013-01-01

8

Sternalis muscle: an underestimated anterior chest wall anatomical variant.  

PubMed

Over the recent years, an increased alertness for thorough knowledge of anatomical variants with clinical significance has been recorded in order to minimize the risks of surgical complications. We report a rare case of bilateral strap-like sternalis muscle of the anterior chest wall in a female cadaver. Its presence may evoke alterations in the electrocardiogram or confuse a routine mammography. The incidental finding of a sternalis muscle in mammography, CT, and MRI studies must be documented in a patient's medical records as it can be used as a pedicle flap or flap microvascular anastomosis during reconstructive surgery of the anterior chest wall, head and neck, and breast. Moreover, its presence may be misdiagnosed as a wide range of benign and malignant anterior chest wall lesions and tumors. PMID:21575244

Raikos, Athanasios; Paraskevas, George K; Tzika, Maria; Faustmann, Pedro; Triaridis, Stefanos; Kordali, Panagiota; Kitsoulis, Panagiotis; Brand-Saberi, Beate

2011-01-01

9

Sternalis muscle: an underestimated anterior chest wall anatomical variant  

PubMed Central

Over the recent years, an increased alertness for thorough knowledge of anatomical variants with clinical significance has been recorded in order to minimize the risks of surgical complications. We report a rare case of bilateral strap-like sternalis muscle of the anterior chest wall in a female cadaver. Its presence may evoke alterations in the electrocardiogram or confuse a routine mammography. The incidental finding of a sternalis muscle in mammography, CT, and MRI studies must be documented in a patient's medical records as it can be used as a pedicle flap or flap microvascular anastomosis during reconstructive surgery of the anterior chest wall, head and neck, and breast. Moreover, its presence may be misdiagnosed as a wide range of benign and malignant anterior chest wall lesions and tumors. PMID:21575244

2011-01-01

10

Effects of myocardial wall thickness on SPECT quantification  

Microsoft Academic Search

The effects of changing myocardial wall thickness in single photon emission computed tomography (SPECT) imaging are characterized, and a method which may be used to compensate for these effects is presented. The underlying principle is that the phenomena of attenuation, Compton scatter, and finite resolution can be separated and treated independently. Only finite resolution and its effects, along with a

J. R. Galt; E. V. Garcia; W. L. Robbins

1990-01-01

11

Changes in myocardial wall thickness (MWT) in open chest dogs  

Microsoft Academic Search

Changes in left ventricular myocardial wall thickness (MWT) were studied in open-chest dogs using a specially designed strain gauge device. The total systolic increase in MWT was 10%, of which about 30% occurred during the isovolumic phase of contraction. These values are lower than those obtained with cineradiographic techniques. A possible explanation for this divergency is discussed. Calculation of MWT

J. J. van der Meer; A. H. M. Jageneau; G. Elzinga; R. Grondelle; R. S. Reneman

1973-01-01

12

Sternalis muscle: an underestimated anterior chest wall anatomical variant  

Microsoft Academic Search

Over the recent years, an increased alertness for thorough knowledge of anatomical variants with clinical significance has\\u000a been recorded in order to minimize the risks of surgical complications. We report a rare case of bilateral strap-like sternalis\\u000a muscle of the anterior chest wall in a female cadaver. Its presence may evoke alterations in the electrocardiogram or confuse\\u000a a routine mammography.

Athanasios Raikos; George K Paraskevas; Maria Tzika; Pedro Faustmann; Stefanos Triaridis; Panagiota Kordali; Panagiotis Kitsoulis; Beate Brand-Saberi

2011-01-01

13

Segmental wall motion abnormalities in dilated cardiomyopathy: hemodynamic characteristics and comparison with thallium-201 myocardial scintigraphy  

SciTech Connect

This study assessed the hemodynamic characteristics of segmental wall motion abnormality of the left ventricle in patients with dilated cardiomyopathy (DCM) and its relation to the thallium-201 (TI-201) myocardial scintigraphy (MPI). Left ventriculograms and MPI in 23 patients were analyzed by the use of quantitative indexes of regional wall motion and TI-201 uptake based on a mean and a standard deviation of 13 normal subjects. Relative normokinesis in our definition was more frequently seen in the inferior wall than in the anterior wall (p less than 0.01). In contrast, severe asynergy was more often seen in the anterior wall than in the inferior wall (p less than 0.01). There were 11 patients who had relative normokinesis and asynergy together. By means of the index of wall motion, the DCM patients were divided into two groups, one with segmental wall motion abnormality (SWMA) and another with diffuse wall motion abnormality (DWMA). The DWMA group had higher left ventricular end-diastolic pressures (p less than 0.05) and the tendency of large left ventricular end-diastolic volumes than the SWMA group. There was a rough correlation (r = 0.58) between the quantitative indexes of TI-201 uptake and wall motion at the same region of the left ventricle. Thus, the nonuniformity of the left ventricular wall motion was recognized in the patients with DCM and more increased preload was shown in the patients with DWMA than in the group with SWMA. Further, the regional asynergy may be related to the localized fibrosis within the left ventricle in DCM, considering the result that the worse TI-201 uptake was roughly accompanied by the more severe asynergy.

Yamaguchi, S.; Tsuiki, K.; Hayasaka, M.; Yasui, S.

1987-05-01

14

Quantification of regional myocardial wall motion by cardiovascular magnetic resonance  

PubMed Central

Cardiovascular magnetic resonance (CMR) is a versatile tool that also allows comprehensive and accurate measurement of both global and regional myocardial contraction. Quantification of regional wall motion parameters, such as strain, strain rate, twist and torsion, has been shown to be more sensitive to early-stage functional alterations. Since the invention of CMR tagging by magnetization saturation in 1988, several CMR techniques have been developed to enable the measurement of regional myocardial wall motion, including myocardial tissue tagging, phase contrast mapping, displacement encoding with stimulated echoes (DENSE), and strain encoded (SENC) imaging. These techniques have been developed with their own advantages and limitations. In this review, two widely used and closely related CMR techniques, i.e., tissue tagging and DENSE, will be discussed from the perspective of pulse sequence development and image-processing techniques. The clinical and preclinical applications of tissue tagging and DENSE in assessing wall motion mechanics in both normal and diseased hearts, including coronary artery diseases, hypertrophic cardiomyopathy, aortic stenosis, and Duchenne muscular dystrophies, will be discussed. PMID:25392821

Jiang, Kai

2014-01-01

15

Quantitative Anatomical Labeling of the Anterior Abdominal Wall  

PubMed Central

Ventral hernias (VHs) are abnormal openings in the anterior abdominal wall that are common side effects of surgical intervention. Repair of VHs is the most commonly performed procedure by general surgeons worldwide, but VH repair outcomes are not particularly encouraging (with recurrence rates up to 43%). A variety of open and laparoscopic techniques are available for hernia repair, and the specific technique used is ultimately driven by surgeon preference and experience. Despite routine acquisition of computed tomography (CT) for VH patients, little quantitative information is available on which to guide selection of a particular approach and/or optimize patient-specific treatment. From anecdotal interviews, the success of VH repair procedures correlates with hernia size, location, and involvement of secondary structures. Herein, we propose an image labeling protocol to segment the anterior abdominal area to provide a geometric basis with which to derive biomarkers and evaluate treatment efficacy. Based on routine clinical CT data, we are able to identify inner and outer surfaces of the abdominal walls and the herniated volume. This is the first formal presentation of a protocol to quantify these structures on abdominal CT. The intra- and inter rater reproducibilities of this protocol are evaluated on 4 patients with suspected VH (3 patients were ultimately diagnosed with VH while 1 was not). Mean surfaces distances of less than 2mm were achieved for all structures. PMID:24478827

Allen, Wade M.; Xu, Zhoubing; Asman, Andrew J.; Poulose, Benjamin K.; Landman, Bennett A.

2013-01-01

16

Malignant Schwannoma of Anterior Abdominal Wall: Report of a Case  

PubMed Central

Malignant schwannoma of the anterior abdominal wall nerves is extremely rare. Malignant peripheral nerve sheath tumors (MPNST) represent approximately 10% of all soft tissue sarcomas and it is found in 4% of patients with neurofibromatosis 1. We present a case of malignant schwannoma in a 28-year-old female patient with neurofibromatosis 1. She presented with a painful mass in the right upper quadrant of her abdomen. The tumor location was in the abdominal wall in explorative laparatomy and malignant schwannoma was diagnosed in pathologic assessment. The tumor recurred in 3 months and computed tomography showed two masses in the right side of abdominopelvic cavity. Thereafter, second complete surgical resection was performed and pathologic finding was the same. In spite of administering chemotherapy after second surgery,the tumor recurred and magnetic resonance imaging finding showed a huge heterogeneously enhancing mass with adhesion to the inner side of the abdominal wall. The patient died because of acute respiratory failure due to multiple bilateral pulmonary metastases. Tumor location and rapid recurrence was unique in our patient. Keywords Malignant peripheral nerve sheath tumor; Malignant schwannoma; Abdominal wall PMID:22461875

Khorgami, Zhamak; Nasiri, Shirzad; Rezakhanlu, Freshteh; Sodagari, Nassim

2009-01-01

17

Studies of regional myocardial blood flow: results in patients with left anterior descending coronary artery disease.  

PubMed

Measurements of regional myocardial blood flow have been performed rapidly and safely in man at the time of coronary arteriography. Xenon-133 was injected into the coronary artery and estimates of myocardial capillary perfusion were made by computer analysis of the multiple precordial tracer washout curves recorded with a scintillation camera. Blood flow rates/100 g/min in different areas of the heart were calculated by the Schmidt-Kety formula, using an assumed partition coefficient, and were related to the coronary vascular lesions by landmarks provided by the arteriograms. The flow significance of lesions was assessed by making measurements at rest and during interventions that increase coronary blood flow. Perfusion was also estimated in areas supplied by collateral vessels, and regions of scar were detected from the initial distribution of peak tracer activity. In patients with less than 50% obstructions apparent on coronary arteriograms and in those with greater than 50% isolated left anterior descending lesions average mean left ventricular (LV) myocardial perfusion values were not reduced below values found in patients with normal coronary arteries and normal cardiac function. However, in patients with significant two-vessel disease (LAD + right, LAD + circ) mean LV perfusion was significantly reduced. Average regional myocardial perfusion distal to significant lesions was not selectively reduced below the remainder of the ventricle unless the lesions were 100% obstructions. However, both total and distal regional myocardial perfusion increased less in 12 patients with greater than 50% lesions than in 12 others with normal arteriograms or less than 50% lesions. Subnormal flow responses in all of the former group were associated with angina pectoris compared with no angina in the latter. The studies indicate the potential utility of the measurements of regional myocardial blood flow in the evaluation of patients with ischemic heart disease who are potential candidates for myocardial revascularization procedures. PMID:941026

Cannon, P J; Weiss, M B; Casarella, W J

1976-07-01

18

Dependence of local left ventricular wall mechanics on myocardial fiber orientation: A model study  

Microsoft Academic Search

The dependence of local left ventricular (LV) mechanics on myocardial muscle fiber orientation was investigated using a finite element model. In the model we have considered anisotropy of the active and passive components of myocardial tissue, dependence of active stress on time, strain and strain rate, activation sequence of the LV wall and aortic afterload. Muscle fiber orientation in the

P. H. M. Bovendeerd; T. Arts; J. M. Huyghe; D. H. VAN CAMPENt; R. S. Renekman

1992-01-01

19

Frequency and significance of myocardial bridging and recurrent segment of the left anterior descending coronary artery in patients with takotsubo cardiomyopathy.  

PubMed

Despite intensive research efforts, the causative mechanisms of takotsubo cardiomyopathy (TC) are still unknown. Recently, morphologic characteristics of the left anterior descending coronary artery (LAD) have been proposed as a potential pathophysiological substrate. Hence, the aim of the present study was to evaluate the prevalence of myocardial bridging and LAD recurrent segments in a large cohort of patients with TC. A total of 161 patients with TC were matched for age and gender with 161 controls without coronary artery or valvular heart disease. Myocardial bridging was diagnosed according to indirect signs in coronary angiography. Furthermore, the LAD was evaluated regarding parts of the vessel outreaching the left ventricular apex (LAD recurrent segment). The prevalence of myocardial bridging was similar in the TC and control groups (11.8% vs 6.8%, p = 0.18). Any part of the LAD outreaching the left ventricular apex was observed in 55.6% of patients with TC compared with 35.4% in the control population (p <0.001). Moreover, the LAD supplied ?25% of the inferior myocardial wall in 21 patients with TC (13.1%), whereas patients in the control group did not show this pattern of coronary circulation at all (p <0.001). Patients with TC with typical apical ballooning compared with those with atypical ballooning patterns demonstrated a higher prevalence of myocardial bridging (p = 0.04) but not LAD recurrent segments (p = 0.28). In conclusion, the prevalence of myocardial bridging in patients with TC is low and comparable with that in a matched control group. In contrast, LAD recurrent segments are significantly more frequent in patients with TC. PMID:25175156

Stiermaier, Thomas; Desch, Steffen; Blazek, Stephan; Schuler, Gerhard; Thiele, Holger; Eitel, Ingo

2014-10-15

20

Manubrial-clavicular-chest wall explantation to expose the anterior thoracic inlet.  

PubMed

The anterior thoracic inlet is difficult to access surgically because of the overlying pectoral-shoulder girdle, clavicle, and manubrium. With both the Dartevelle and Grunenwald approaches, retraction of an osteomuscular flap is required, and patients may be left with the functional and aesthetic implications of partial clavicular resection. We describe a novel technique involving manubrial-clavicular-chest wall explantation with preservation and reimplantation. Manubrial and clavicular plating is performed to stabilize the anterior chest wall and clavicle after reimplantation. This approach represents an alternative technique that provides excellent visualization of the entire anterior thoracic inlet. PMID:24384199

Seder, Christopher W; Elhassan, Bassem T; Wigle, Dennis A

2014-01-01

21

Chest wall reconstruction using pedicled extended serratus anterior myocutaneous flap combined with vascularized rib  

Microsoft Academic Search

An extended serratus anterior myocutaneous flap with a vascularized rib has been used, in two cases, for reconstruction of large full-thickness chest wall defects after resection of recurrent breast cancer. Using this method, the bony support and the soft tissue of the chest wall can be safely reconstructed.

T. Inoue; S. Ohba; A. Takamatus; T. Kitazawa; T. Harashina

1996-01-01

22

Choledochoduodenal fistula at the anterior wall of the duodenal bulb: a rare complication of duodenal ulcer.  

PubMed

A 38 year-old man was admitted to our hospital with the chief complaint of epigastralgia. His laboratory data revealed leukocytosis and increased serum amylase, and abdominal ultrasonography revealed diffuse swelling of the pancreas. Thus, he was diagnosed as having acute pancreatitis. Moreover, abdominal computed tomography showed pneumobilia in the gallbladder and the common bile duct. Gastroduodenal fiberscopy demonstrated peptic ulcer scars around a foramen with smooth margins at the anterior wall of the duodenal bulb. The bile juice flowed from the bottom of the foramen. Endoscopic retrograde cholangiopancreatography revealed the fistula between the common bile duct and the anterior wall of the duodenal bulb, but not the posterior wall. However, there was no pancreatico-biliary maljunction and no stones in the gallbladder or bile duct. This is a rare case of choledochoduodenal fistula at the anterior wall of the duodenal bulb caused by duodenal peptic ulcer disease. PMID:10228804

Shimao, K; Yamaue, H; Nishimoto, N; Terasawa, H; Saigan, S; Onishi, H; Tanimura, H; Hashimoto, T

1999-01-01

23

Relationship between acute strain pattern and recovery in tako-tsubo cardiomyopathy and acute anterior myocardial infarction: a comparative study using two-dimensional longitudinal strain.  

PubMed

After acute-anterior myocardial infarction (AMI), left ventricular (LV) viable myocardial segments show some degree of active deformation (longitudinal shortening) despite wall motion abnormalities (WMA). Tako-tsubo cardiomyopathy (TTC) is characterized by myocardial stunning; however, it is unclear whether in TTC the strain pattern mimics AMI. To compare the strain-pattern in TTC and AMI using the 2D-longitudinal strain by speckle-tracking in segments with WMA, and its relationship with recovery of function at follow-up. 21 consecutive patients with typical TTC and 21 age-matched AMI patients treated by primary angioplasty had an analysis of LV-longitudinal strain at the acute-phase and at follow-up (1 and 6 months later for TTC and AMI respectively). The recovery of a segment was defined as normal wall motion at follow-up. Among the 706 analyzable LV-segments at the acute-phase, 406 had WMA (TTC 229, AMI 177). At follow-up, total recovery was observed for 45 % segments in AMI and 100 % in TTC, (p < 0.01). At the acute phase, systolic lengthening duration (47 ± 43 vs. 18 ± 33 %) and amplitude (0.25 ± 0.29 vs. 0.09 ± 0.19) and post systolic shortening (67 ± 53 vs. 39 ± 38 %) were higher in TTC, when compared to AMI-recovery (all, p < 0.01). In AMI, systolic lengthening duration was an independent predictor of poor recovery in multivariate analysis, linked to segmental longitudinal strain at follow-up (all, p ? 0.01). Furthermore, among the 57 % of segments exhibiting any systolic lengthening duration in AMI, only ¼ recovered, versus 62 % of such segments in TTC with 100 % recovery (p < 0.001). The systolic passive motion which is closely and inversely linked to recovery in AMI is paradoxically frequent and severe in TTC. This suggests that myocardial stunning in TTC and AMI is different according to longitudinal strain. PMID:25037469

Meimoun, Patrick; Abouth, Shirley; Boulanger, Jacques; Luycx-Bore, Anne; Martis, Sonia; Clerc, Jérome

2014-12-01

24

Video endoscopic oro-nasal visualisation of the anterior wall of maxillary sinus: a new technique.  

PubMed

The anterior wall of the maxillary sinus represents a blind spot in maxillary sinus endoscopic surgery because of the absence of proper visualisation and instrumentation to reach it. The aim of this study was to validate a new approach through the oral cavity into the nose with a flexible video endoscope (oro-nasal endoscopic approach; ONEA) to visualise the entire anterior maxillary wall including the anteromedial angle. We started from a dried bone cadaver model, and then dissected fresh-frozen cadavers. The maxillary sinus was explored with a rigid and a flexible endoscope entering from the nose. Next, a flexible endoscope was introduced through the mouth and back up through the choana, it accessed the maxillary middle antrostomy, entering inside the sinus and looking at the anterior wall. A small ruler inserted inside the sinus demonstrated all the angles visualised. The new ONEA technique allows complete visualisation of the anterior wall of the maxillary sinus with inspection of all blind spots. It is therefore possible to detect lesions that would normally not be visible with a normal rigid endoscope. We demonstrate the validity of a novel technique that allows visualisation of the infero-medial angle of the anterior wall of the maxillary sinus. PMID:25210220

Trimarchi, M; Tomazic, P V; Bertazzoni, G; Rathburn, A; Bussi, M; Stammberger, H

2014-08-01

25

The ratio between anterior abdominal wall surface\\/wall defect surface: a new parameter to classify abdominal incisional hernias  

Microsoft Academic Search

Current classifications of incisional hernias are often not suitable. The aim of our study was to demonstrate that it is important\\u000a to consider not only the wall defect surface (WDS) but also the total surface of the anterior abdominal wall (SAW) and the\\u000a ratio between SAW\\/WDS). Twenty-three patients affected by >10 cm size incisional hernias were examined for anthropometric\\u000a analyses. The

C. Ammaturo; G. Bassi

2005-01-01

26

Subacute left ventricle free wall rupture after acute myocardial infarction: awareness of the clinical signs and early use of echocardiography may be life-saving  

PubMed Central

Left ventricular free wall rupture (LVFWR) is a fearful complication of acute myocardial infarction in which a swift diagnosis and emergency surgery can be crucial for successful treatment. Because a significant number of cases occur subacutely, clinicians should be aware of the risk factors, clinical features and diagnostic criteria of this complication. We report the case of a 69 year-old man in whom a subacute left ventricular free wall rupture (LVFWR) was diagnosed 7 days after an inferior myocardial infarction with late reperfusion therapy. An asymptomatic 3 to 5 mm saddle-shaped ST-segment elevation in anterior and lateral leads, detected on a routine ECG, led to an urgent bedside echocardiogram which showed basal inferior-wall akinesis, a small echodense pericardial effusion and a canalicular tract from endo to pericardium, along the interface between the necrotic and normal contracting myocardium, trough which power-Doppler examination suggested blood crossing the myocardial wall. A cardiac MRI further reinforced the possibility of contained LVFWR and a surgical procedure was undertaken, confirming the diagnosis and allowing the successful repair of the myocardial tear. This case illustrates that subacute LVFWR provides an opportunity for intervention. Recognition of the diversity of presentation and prompt use of echocardiography may be life-saving. PMID:17118207

Raposo, Luis; Andrade, Maria Joao; Ferreira, Jorge; Aguiar, Carlos; Couto, Rute; Abecasis, Miguel; Canada, Manuel; Jalles-Tavares, Nuno; da Silva, Jose Aniceto

2006-01-01

27

Single-center 10-year experience in the management of anterior abdominal wall defects  

Microsoft Academic Search

Background  Anterior abdominal wall defects can be managed with various techniques, since no one technique can be applied to all types\\u000a of defects. The aim of this study is to present a single-center experience using biomaterials and evaluate the outcomes.\\u000a \\u000a \\u000a \\u000a Methods  The clinical data obtained from 33 neonates (24 gastroschisis and 9 omphaloceles) managed for anterior abdominal wall defects\\u000a at a single

S. Rahn; M. Bahr; J. Schalamon; A. K. Saxena

2008-01-01

28

Concomitant surgical correction of severe stress urinary incontinence and anterior vaginal wall prolapse by anterior vaginal wall wrap: 18 months outcomes  

PubMed Central

Background: The aim of this study is to evaluate the outcome of an innovative, minimally invasive sling technique with autologous tissue in women with concomitant incontinence and anterior vaginal wall prolapse (AVWP). Materials and Methods: Fifty-six women with stress urinary incontinence (SUI) or mixed urinary incontinence and AVWP were randomly assigned into two groups: In Group A (26 patients), anterior colporrhaphy (Kelly placation) and sling placement using a strip of anterior vaginal wall were performed, and in Group B (30 patients), transvaginal mesh correction of AVWP and tension-free vaginal tape (TVT) insertion (retropubic – craniocaudal route) using polypropylene mesh were carried out. The patients were followed-up for over 18 months and were assessed objectively using a 48 h frequency-volume chart, a 48 h pad test and a standardized stress test. Related surgical complications and outcomes were recorded and compared. Results: Surgical cure rates for Group A and Group B at the first (3 days) and last (18 months) post-operative visits were 62% and 84%; and 54%, and 72%, respectively (P = 0.09 and 0.31). Complications occurred in 9 patients (44%) of Group B, but only 3 patients (12%) in Group A. Conclusion: Vaginal sling surgery using an anterior vaginal wall strip can improve SUI and in comparison with propylene mesh is associated with lower complication rates. Although, the surgical success rate of this technique is lower than T-Sling, larger studies with selected patients will help assess the suitable patients for this pelvic reconstructive surgery. PMID:24516492

Zargham, Mahtab; Alizadeh, Farshid; Tadayyon, Farhad; Khorrami, Mohammad-Hatef; Nouri-Mahdavi, Kia; Gharaati, Mohammad Reza; Izadpanahi, Mohammad Hossein; Yazdani, Mohammad; Mazdak, Hamid

2013-01-01

29

Chondrosarcoma of the anterior chest wall: surgical resection and reconstruction with titanium mesh  

PubMed Central

Primary malignant tumors of the chest wall are uncommon. Chondrosarcoma is the most common malignancy of the sternum. The current therapy for chondrosarcoma requires adequate surgical excision. A 52-year-old man presented with a lower-sternal mass. Thorax computed tomography (CT) revealed a well-lineated, hypodense and round mass, which highly suggested the sarcoma of the chest wall. The tumor involved 1/3 distal part of the corpus sterni. Incisional biopsy of the mass was reported as chondrosarcoma. In order to obtain disease-free surgical margins, 1/3 distal part of the sternum with costochondral junctions was resected and reconstruction of anterior chest wall was performed with titanium mesh. The postoperative course was uneventful. The titanium mesh provided the essential rigidity and minimal elasticity over the surgical wound. Our findings show that this technique is adequate even for reconstructing extensive defects of the anterior chest wall. PMID:25364538

Ersoz, Elcin; Evman, Serdar; Alpay, Levent; Aky?l, Mustafa; Vayvada, Mustafa; Gurer, Deniz; Bayram, Serkan

2014-01-01

30

Seronegative arthritides of the anterior chest wall: a follow-up study  

Microsoft Academic Search

Fourteen patients with arthritis of the anterior chest wall (ACW) as part of ankylosing spondylitis, reactive arthritis, and arthritis associated with psoriasis and\\/ or pustulosis palmoplantaris (PPP) were re-examined after periods of 5–15 years (mean 9 years) using tomography. The findings were compared with those of 24 similarly examined patients with predominant osseous sclerotic ACW lesions or monarthritis of the

A. G. Jurik

1991-01-01

31

A free fibula autologous transfer for a full-thickness anterior chest wall defect  

Microsoft Academic Search

Large defects of the anterior chest wall lead to gross chest instability which can result in paradoxical respiration. Skeletal stabilization is an essential requirement in such cases. The current methods for achieving total or near total sternal reconstructions involve the use of alloplastic implant materials: prosthetic mesh with methyl methacrylate. In our experience, this method of reconstruction is often complicated

D. Cunha-Gomes; H. M. Bhathena; N. M. Kavarana; R. Mistry; A. R. Fakih

2001-01-01

32

Anatomic Distribution of Nerves and Microvascular Density in the Human Anterior Vaginal Wall: Prospective Study  

PubMed Central

Background The presence of the G-spot (an assumed erotic sensitive area in the anterior wall of the vagina) remains controversial. We explored the histomorphological basis of the G-spot. Methods Biopsies were drawn from a 12 o’clock direction in the distal- and proximal-third areas of the anterior vagina of 32 Chinese subjects. The total number of protein gene product 9.5–immunoreactive nerves and smooth muscle actin–immunoreactive blood vessels in each specimen was quantified using the avidin-biotin-peroxidase assay. Results Vaginal innervation was observed in the lamina propria and muscle layer of the anterior vaginal wall. The distal-third of the anterior vaginal wall had significantly richer small-nerve-fiber innervation in the lamina propria than the proximal-third (p?=?0.000) and in the vaginal muscle layer (p?=?0.006). There were abundant microvessels in the lamina propria and muscle layer, but no small vessels in the lamina propria and few in the muscle layer. Significant differences were noted in the number of microvessels when comparing the distal- with proximal-third parts in the lamina propria (p?=?0.046) and muscle layer (p?=?0.002). Conclusions Significantly increased density of nerves and microvessels in the distal-third of the anterior vaginal wall could be the histomorphological basis of the G-spot. Distal anterior vaginal repair could disrupt the normal anatomy, neurovascular supply and function of the G-spot, and cause sexual dysfunction. PMID:25379731

Li, Ting; Liao, Qinping; Zhang, Hong; Gao, Xuelian; Li, Xueying; Zhang, Miao

2014-01-01

33

Pedicled omental and split skin graft in the reconstruction of the anterior abdominal wall?  

PubMed Central

INTRODUCTION The POSSG is a pedicled graft based on either the right or left gastro-epiploic arteries. It is used with a dual mesh in reconstruction of full thickness defects of anterior abdominal wall and covered by skin grafts. PRESENTATION OF CASE A recurrent malignant peripheral nerve sheath tumor (MPNST) of the anterior abdominal wall was excised leaving a large defect. The POSSG was used for reconstruction. A large dual mesh was placed to close the defect in the abdominal wall by suturing it to the remnant rim of abdominal muscles. The omental pedicle was brought through a keyhole in the mesh, spread out over the mesh, sutured and covered by split skin grafts. The final graft take was 90 percent. DISCUSSION The POSSG can be used to reconstruct any size of anterior abdominal wall defects due to the malleable nature of omentum. Its prerequisite however is a dual mesh like PROCEED. The POSSG helps keep the more complex musculofasciocutaneous flaps as lifeboats. It can be used singly where multiple musculofasciocutaneous flaps would otherwise have been required. It can be used in patients with poor prognosis of underlying malignancy. It may be used by general surgeons due to familiarity with anatomy of the relevant structures and lack of need for microsurgical skill. CONCLUSION The POSSG can be used in reconstruction of abdominal wall defects of any size by general surgeons. PMID:24566428

Manay, Priyadarshini; Khajanchi, Monty; Prajapati, Ram; Satoskar, Rajeev

2014-01-01

34

Perineal approach for a gastrointestinal stromal tumor on the anterior wall of the lower rectum  

PubMed Central

Background Wide margins of resection and regional lymphadenectomy for GIST are not necessary. Several procedures for rectal GIST have been designed according to the location and size of the tumor to preserve the anal function and decrease the morbidity rate. Case presentation We report a 61-year-old-man with rectal bleeding. Proctologic examination revealed a small mass of approximately 2 cm in diameter on the anterior wall of the rectum at a distance of 4 cm from the anal verge. Histological examination of the biopsy sample via the rectum led to a diagnosis of GIST due to immunohistochemical positivity for C117 and CD34. Perineal resection was planned because abdominoperineal resection with sacrificing the sphincter function was excessive for this small tumor, and low anterior resection with the double stapling technique was difficult due to the lower position. A hemispheric incision was made from one mid-ischial tuberosity to the other with an apex of approximately 2 cm above the anus. The fascia band and muscles were successively transected in order to expose the anterior wall of the rectum, and excision of the tumor was performed. The postoperative course was uneventful, and the patient remained free from incontinence and recurrence. Conclusions This perineal approach for a GIST on the anterior wall of the rectum is one option for preserving the anal function and decreasing the morbidity rate. PMID:24666640

2014-01-01

35

An alternative technique for anterior chest wall reconstruction: the sternal allograft transplantation  

PubMed Central

OBJECTIVES Sternal resection is indicated for a variety of pathological conditions, mainly neoplastic or related to sternotomy complications. Resection of the sternum generally leaves a large chest-wall defect, and reconstruction is thus the most difficult part of the operation. Correct stabilization of the anterior chest wall is very important to avoid secondary complications and respiratory failure. In the last few years, different technical solutions have been used to reconstruct the sternum. We describe our technique using a sternal allograft to reconstruct the anterior chest wall after partial or complete sternal resection. METHODS Between June 2010 and February 2012, four patients underwent sternectomy followed by anterior chest wall reconstruction using sternal allograft. The sternal allograft was harvested from a multitissue donor following Italian legislation for tissue donation. Three patients had neoplastic involvement of the sternum, and one had a complete sternal defect as a complication of a cardiac operation. RESULTS We had no operative mortality. Three patients underwent partial sternal transplantation, and one underwent total sternal replacement. We had no postoperative respiratory insufficiency, infections or mechanical failure of the reconstructions. The respiratory function was preserved in all patients. The follow-up period was free from complications related to the sternal allograft implantation. CONCLUSIONS The technique of sternal allograft transplantation is simple, reproducible and provides excellent functional and cosmetic results. Further studies including a larger number of patients are needed to understand the biology of the allograft and the long-term results of this technique. PMID:22990634

Dell'Amore, Andrea; Cassanelli, Nicola; Dolci, Giampiero; Stella, Franco

2012-01-01

36

Prehospital 12-Lead Electrocardiogram within 60 Minutes Differentiates Proximal versus Nonproximal Left Anterior Descending Artery Myocardial Infarction  

PubMed Central

Introduction Acute anterior myocardial infarctions caused by proximal left anterior descending (LAD) artery occlusions are associated with a higher morbidity and mortality. Early identification of high-risk patients via the 12-lead electrocardiogram (ECG) could assist physicians and emergency response teams in providing early and aggressive care for patients with anterior ST-elevation myocardial infarctions (STEMI). Approximately 25% of US hospitals have primary percutaneous coronary intervention (PCI) capability for the treatment of acute myocardial infarctions. Given the paucity of hospitals capable of PCI, early identification of more severe myocardial infarction may prompt emergency medical service routing of these patients to PCI-capable hospitals. We sought to determine if the 12 lead ECG is capable of predicting proximal LAD artery occlusions. Methods In a retrospective, post-hoc analysis of the Pre-Hospital Administration of Thrombolytic Therapy with Urgent Culprit Artery Revascularization pilot trial, we compared the ECG findings of proximal and nonproximal LAD occlusions for patients who had undergone an ECG within 180 minutes of symptom onset. Results In this study, 72 patients had anterior STEMIs, with ECGs performed within 180 minutes of symptom onset. In patients who had undergone ECGs within 60 minutes (n = 35), the mean sum of ST elevation (STE) in leads V1 through V6 plus ST depression (STD) in leads II, III, and aVF was 19.2 mm for proximal LAD occlusions and 11.7 mm for nonproximal LAD occlusions (P = 0.007). A sum STE in V1 through V6 plus STD in II, III, and aVF of at least 17.5 mm had a sensitivity of 52.3%, specificity of 92.9%, positive predictive value of 91.7%, and negative predictive value of 56.5% for proximal LAD occlusions. When the ECG was performed more than 60 minutes after symptom onset (n = 37), there was no significant difference in ST-segment deviation between the 2 groups. Conclusion The sum STE (V1-V6) and STD (II, III, aVF) on a 12-lead ECG can be used to predict proximal LAD occlusions if performed within the first hour of symptom onset. This should be considered a high-risk finding and may prompt prehospital direction of such patients to PCI-capable hospitals. PMID:22224129

Aertker, Robert A; Barker, Colin M; Anderson, H. Vernon; Denktas, Ali E; Giesler, Gregory M; Julapalli, Vinay R; Ledoux, John F; Persse, David E; Sdringola, Stefano; Vooletich, Mary T; McCarthy, James J; Smalling, Richard W

2011-01-01

37

Laparoscopic Sacrocolpopexy with Two Separate Meshes along the Anterior and Posterior Vaginal Walls for Multicompartment Pelvic Organ Prolapse  

Microsoft Academic Search

Study ObjectiveTo assess the feasibility and results of laparoscopic sacrocolpopexy (LSC) with two separate meshes along the anterior and posterior vaginal walls in correcting multicompartment pelvic organ prolapse (POP).

Pierre Gadonneix; Alfredo Ercoli; Delphine Salet-Lizée; Odile Cotelle; Brigitte Bolner; Michel Van Den Akker; Richard Villet

2004-01-01

38

Anomalous course of the left anterior descending coronary artery between the aorta and pulmonary trunk: a rare cause of myocardial ischaemia at rest.  

PubMed Central

When the left anterior descending coronary artery follows an anomalous course between the aorta and pulmonary artery it can cause myocardial ischaemia or sudden death during exercise in young people. Coronary arteriography in a 27 year old man with angina pectoris at rest showed a left anterior descending coronary artery arising from a common right trunk and running from the aorta to the pulmonary artery. Follow up after revascularisation was uneventful. Images PMID:7833201

Roynard, J L; Cattan, S; Artigou, J Y; Desoutter, P

1994-01-01

39

Sturdivan's formula revisited: MRI assessment of anterior chest wall thickness for injury risk prediction of blunt ballistic impact trauma  

Microsoft Academic Search

BackgroundThe thickness and composition of the chest wall are important quantities in multiparametric trauma models for the assessment of injury severity due to blunt ballistic chest impact. While ballistic parameters of non-penetrating projectiles can routinely be measured with high accuracy, data on the thickness of the anterior chest wall is unreliable. Therefore, it is the aim of this work to

Matthias Frank; Volker Schorge; Katrin Hegenscheid; Anselm Angermaier; Axel Ekkernkamp; Norbert Hosten; Ralf Puls; Soenke Langner

2011-01-01

40

Study of myocardial regional wall motion parameter's accuracy by software perfusion phantom.  

PubMed

Gated perfusion myocardial scintigraphy permits simultaneous evaluation of perfusion as well as regional contractile function of the left ventricle. Fourier analysis of regional myocardial spatial movement with respect to the myocardial geometric centre gives circular amplitude and phase profiles of ventricular contraction, in addition to regional maximum activity that represents an index of perfusion. To introduce such combined perfusion-contraction analysis the accuracy of the indices mentioned above should be evaluated for different doses of radioactivity typically administered to a patient. A mathematical software phantom, consisting of a half circularly profiled ring activity embedded in uniform background activity and noise generated by a Poisson-shaped random number generator, was constructed and used for this purpose. A 64 x 64 matrix and sequence of 16 frames per study was used. The maximum number of counts per pixel ranged from 10 to 100, simulating low count thallium and high count rate Tc-MIBI-gated studies. The relative standard error analysis (R.S.E.) with a 95.5% confidence level for a thallium type of 10 counts per pixel study exceeded 11%, while it reached acceptable values below 3% for studies with 60 and more counts per pixel. These results indicate that high count rate gated technetium-MIBI myocardial perfusion studies could also be used for reliable left ventricular regional wall motion evaluation. PMID:1407874

Fidler, V; Fettich, J; Prepadnik, M

1992-06-01

41

Septal myocardial perfusion imaging with thallium-201 in the diagnosis of proximal left anterior descending coronary artery disease  

SciTech Connect

The use of myocardial perfusion imaging (MPI) to identify obstructive coronary disease of the left anterior descending coronary artery proximal to the first septal perforator (prox LAD) was studied in 60 patients. Perfusion of the septum and anteroapical areas with thallium-201 injected during exercise was compared to results of coronary arteriography. Septal MPI defect was found in 92.3% of patients with obstruction of the proximal LAD, 27.7% of patients with obstruction of LAD distal to first septal perforator, 0% in patients with obstructions involving right or circumflex arteries, and in 10.5% of patients without coronary disease. Anteroapical MPI defects were found with similar frequency in the three groups with obstructive coronary disease. Septal MPI defect had a sensitivity of 92.3% and specificity of 85.4% in the diagnosis of proximal LAD disease. Normal septal perfusion with thallium-201 virtually excluded proximal LAD disease.

Pichard, A.D.; Wiener, I.; Martinez, E.; Horowitz, S.; Patterson, R.; Meller, J.; Goldsmith, S.J.; Gorlin, R.; Herman, M.V.

1981-07-01

42

The ratio between anterior abdominal wall surface/wall defect surface: a new parameter to classify abdominal incisional hernias.  

PubMed

Current classifications of incisional hernias are often not suitable. The aim of our study was to demonstrate that it is important to consider not only the wall defect surface (WDS) but also the total surface of the anterior abdominal wall (SAW) and the ratio between SAW/WDS). Twenty-three patients affected by > 10 cm size incisional hernias were examined for anthropometric analyses. The SAW, the WDS and the ratio SAW/WDS were calculated. All of the 23 patients were operated on 13 patients were treated with the Rives technique using a polypropylene mesh while the remaning ten patients had an intraperitoneal Parietex Composite mesh (PC). The two groups were compared for post-operative pain (with VAS) and intra-abdominal pressure (IAP) 48 h after the operation: bladder pressure, length of the procedure, average hospital stay and return to work were calculated. In the Rives group, WDS being equal, the higher IAP values were, the lower was the ratio SAW/WDS; furthermore, SAW/WDS ratio being equal, IAP values were low in cases where intraperitoneal mesh was used. Post-operative pain, measured with VAS, was critical when there was a low SAW/WDS ratio and a high IAP. In our experience, it is possible to predict a strong abdominal wall tension if the SAW/WDA ratio is below 15 mmHg. In these cases it is advisable to use a technique requiring the use of an intraperitoneal mesh. Our experience with PC was so positive that it is used in our department for all cases where an intraperitoneal mesh is required. At present, our proposal is that the SAW/WDS ratio is to be considered as a new parameter in current classifications of incisional hernias. PMID:16172802

Ammaturo, C; Bassi, G

2005-12-01

43

Dependence of local left ventricular wall mechanics on myocardial fiber orientation: a model study.  

PubMed

The dependence of local left ventricular (LV) mechanics on myocardial muscle fiber orientation was investigated using a finite element model. In the model we have considered anisotropy of the active and passive components of myocardial tissue, dependence of active stress on time, strain and strain rate, activation sequence of the LV wall and aortic afterload. Muscle fiber orientation in the LV wall is quantified by the helix fiber angle, defined as the angle between the muscle fiber direction and the local circumferential direction. In a first simulation, a transmural variation of the helix fiber angle from +60 degrees at the endocardium through 0 degrees in the midwall layers to -60 degrees at the epicardium was assumed. In this simulation, at the equatorial level maximum active muscle fiber stress was found to vary from about 110 kPa in the subendocardial layers through about 30 kPa in the midwall layers to about 40 kPa in the subepicardial layers. Next, in a series of simulations, muscle fiber orientation was iteratively adapted until the spatial distribution of active muscle fiber stress was fairly homogeneous. Using a transmural course of the helix fiber angle of +60 degrees at the endocardium, +15 degrees in the midwall layers and -60 degrees at the epicardium, at the equatorial level maximum active muscle fiber stress varied from 52 kPa to 55 kPa, indicating a remarkable reduction of the stress range. Moreover, the change of muscle fiber strain with time was more similar in different parts of the LV wall than in the first simulation. It is concluded that (1) the distribution of active muscle fiber stress and muscle fiber strain across the LV wall is very sensitive to the transmural distribution of the helix fiber angle and (2) a physiological transmural distribution of the helix fiber angle can be found, at which active muscle fiber stress and muscle fiber strain are distributed approximately homogeneously across the LV wall. PMID:1400513

Bovendeerd, P H; Arts, T; Huyghe, J M; van Campen, D H; Reneman, R S

1992-10-01

44

Comprehensive analysis of myocardial infarction due to left circumflex artery occlusion: comparison with infarction due to right coronary artery and left anterior descending artery occlusion  

SciTech Connect

Forty consecutive patients with creatine kinase-MB confirmed myocardial infarction due to circumflex artery occlusion (Group 1) were prospectively evaluated and compared with 107 patients with infarction due to right coronary artery occlusion (Group 2) and 94 with left anterior descending artery occlusion (Group 3). All 241 patients underwent exercise thallium-201 scintigraphy, radionuclide ventriculography, 24 h Holter electrocardiographic (ECG) monitoring and coronary arteriography before hospital discharge and were followed up for 39 +/- 18 months. There were no significant differences among the three infarct groups in age, gender, number of risk factors, prevalence and type of prior infarction, Norris index, Killip class and frequency of in-hospital complications. Acute ST segment elevation was present in only 48% of patients in Group 1 versus 71 and 72% in Groups 2 and 3, respectively (p = 0.012), and 38% of patients with a circumflex artery-related infarct had no significant ST changes (that is, elevation or depression) on admission (versus 21 and 20% for patients in Groups 2 and 3, respectively) (p = 0.001). Abnormal R waves in lead V1 were more common in Group 1 than in Group 2 (p less than 0.003) as was ST elevation in leads I, aVL and V4 to V6 (p less than or equal to 0.048). These differences in ECG findings between Group 1 and 2 patients correlated with a significantly higher prevalence of posterior and lateral wall asynergy in the group with a circumflex artery-related infarct. Infarct size based on peak creatine kinase levels and multiple radionuclide variables was intermediate in Group 1 compared with that in Group 2 (smallest) and Group 3 (largest). During long-term follow-up, the probability of recurrent cardiac events was similar in the three infarct groups.

Huey, B.L.; Beller, G.A.; Kaiser, D.L.; Gibson, R.S.

1988-11-01

45

Associated influence of hypertension and heart rate greater than 80 beats per minute on mortality rate in patients with anterior wall STEMI  

PubMed Central

Acute myocardial infarction as a form of coronary heart disease is characterized by permanent damage/loss of anatomical and functional cardiac tissue. Diagnosis of STEMI includes data on anginal pain and persistent ST-segment elavation. According to the numerous epidemiological studies, arterial blood pressure and heart rate are offten increased especially during the first hours of pain due to domination of sympathetic response. We wanted to investigate the associated influence of heart rate greater than 80 beats per minute and hypertension on the mortality in patients with anterior wall STEMI. Research included 140 patients treated in Coronary Unit, Clinical Center Kragujevac form January 2001 to June 2006. Heart rate was calculated as the mean value of baseline and heart rate in the first 30 minutes after admission, recorded on monitor and electrocardiogram. Data for history of hypertension were collected and blood pressure levels were measured in a lying position after 5 minutes of rest, and classified according to the VII JNC recommendations as confirmation of hypertension. Collected data were analyzed in SPSS 13.0 for Windows. Heart rate greater than 80 bpm influences the hospital mortality. Systolic blood pressure levels were higher in the survivors, while for the diastolic there was no difference. History of hypertension was singled out as a significant predictor of mortality without difference between the respondents with heart rate greater and lower than 80 bpm in the survivors and fatal. Increased heart rate and hypertension at admission are significant predictors of mortality in patients with anterior wall STEMI. PMID:23724155

Davidovic, Goran; Iric-Cupic, Violeta; Milanov, Srdjan

2013-01-01

46

A prospective comparison of echocardiographic wall motion score index and radionuclide ejection fraction in predicting outcome following acute myocardial infarction  

Microsoft Academic Search

OBJECTIVETo characterise echocardiographic wall motion score index (WMSI) as a surrogate measure of left ventricular ejection fraction (EF) following acute myocardial infarction (AMI) and to compare its prognostic value with that of EF measured by radionuclide ventriculography (RNV).DESIGNA prospective study to compare baseline echocardiographic WMSI with RNV EF in consecutive patients thrombolysed for AMI, both performed on the same day

G I W Galasko; S Basu; A Lahiri; R Senior

2001-01-01

47

The spectrum of right ventricular involvement in inferior wall myocardial infarction: a clinical, hemodynamic and noninvasive study  

SciTech Connect

The clinical experience with 37 patients with acute transmural inferior wall myocardial infarction who were assessed for evidence of right ventricular involvement is reported. On the basis of currently accepted hemodynamic criteria, 29 patients (78%) had evidence suggestive of right ventricular infarction. However, only 5 (20%) of 25 patients demonstrated right ventricular uptake of technetium pyrophosphate on scintigraphy. Two-dimensional echocardiography or isotope nuclear angiography, or both, were performed in 32 patients; 20 studies (62%) showed evidence of right ventricular wall motion disturbance or dilation, or both. Twenty-one patients demonstrated a late inspiratory increase in the jugular venous pressure (Kussmaul's sign). The presence of this sign in the clinical setting of inferior wall myocardial infarction was predictive for right ventricular involvement in 81% of the patients in this study. It is suggested that right ventricular involvement in this clinical setting is common and includes not only infarction but also dysfunction without detectable infarction, which is likely on an ischemic basis.

Baigrie, R.S.; Haq, A.; Morgan, C.D.; Rakowski, H.; Drobac, M.; McLaughlin, P.

1983-06-01

48

Anterior chest wall elevation using a T-fastener suture technique during a Nuss procedure.  

PubMed

The most critical part of the Nuss procedure is the passage of the introducer across the anterior mediastinum without cardiac injury. For patients with severe pectus excavatum, passing the introducer can be difficult and hazardous. We describe a technique that resembles a use of T-fastenerlike suture material to elevate the anterior chest. The elevation of the chest allows safe, blunt anterior mediastinal dissection before the passage of the introducer. The risk of intraoperative cardiac perforation is minimized. PMID:25087810

Kim, Daabin; Idowu, Olajire; Palmer, Barnard; Kim, Sunghoon

2014-08-01

49

Reversal of segmental hypokinesis by coronary angioplasty in patients with unstable angina, persistent T wave inversion, and left anterior descending coronary artery stenosis. Additional evidence for myocardial stunning in humans  

SciTech Connect

To evaluate the significance of persistent negative T waves during severe ischemia, we prospectively studied 62 patients admitted for unstable angina without evidence of recent or ongoing myocardial infarction. A critical stenosis on the left anterior descending coronary artery (LAD), considered as the culprit lesion, was successfully treated by percutaneous transluminal coronary angioplasty (PTCA). The patients were divided into two groups according to the admission electrocardiogram: T NEG group (n = 32) had persistent negative T waves, and the T POS group (n = 30) had normal positive T waves on precordial leads. The two groups had similar baseline clinical, hemodynamic, and angiographic characteristics. All patients underwent a complete clinical and angiographic evaluation (coronary arteriography and left ventriculography) before undergoing PTCA and 8 +/- 3 months later. Left ventricular anterior wall motion was evaluated by the percent shortening of three areas (S1, S2, and S3) considered as LAD-related segments on left ventriculograms. Before PTCA, there was no significant difference in global ejection fraction between the two groups despite a significant depression in anterior mean percent area shortening in the T NEG compared with the T POS group (S1, 44 versus 54, p less than 0.01; S2, 39 versus 48, p less than 0.01; S3, 44 versus 50, NS). At repeated angiography, the anterior mean percent area shortening improved significantly in the T NEG group (S1, from 44 to 61, p less than 0.001; S2, from 39 to 58, p less than 0.001; S3, from 44 to 61, p less than 0.001).

Renkin, J.; Wijns, W.; Ladha, Z.; Col, J. (Univ. of Louvain Medical School, Brussels (Belgium))

1990-09-01

50

Reconstruction of the Anterior Chest Wall After Subtotal Sternectomy for Metastatic Breast Cancer: Report of a Case  

Microsoft Academic Search

We describe our successful operative management of a solitary metastasis in the sternal body after modified left mastectomy.\\u000a Because the primary lesion was well controlled and the sternal metastasis was isolated, we performed a subtotal sternectomy,\\u000a with full-thickness resection of the anterior chest wall, including the sternal body and inferior part of the manubrium (14.5?cm\\u000a × 8.5?cm × 3.0?cm). A

Haruhiko Nakamura; Norihito Kawasaki; Masahiko Taguchi; Tomoki Kitaya

2007-01-01

51

Vaginal Repair of Cystocele with Anterior Wall Mesh via Transobturator Route: Efficacy and Complications with Up to 3-Year Followup  

PubMed Central

Study Objective. The objective of this study was to report on the safety and efficacy of cystocele repair with anterior wall mesh placed via a transobturator route (Perigee system, AMS, Minnetonka, MN). Design. Single center retrospective study. Setting. Single center hospital setting and Urogynecology practice in the United States. Patients. 77 women presenting with symptomatic anterior wall prolapse. Intervention. Repair of cystocele with an anterior wall Type I soft-polypropylene mesh placed via a transobturator approach. Concomitant procedures in other compartment were also completed as indicated. Measurements and Main Results. 77 women underwent the Perigee procedure at our institution over a 2-year period. The mesh was attached to the pelvic sidewalls at the level of the bladder neck and near the ischial spine apically with needles passed through the groins and obturator space. Mean follow-up was 18.2 months (range 3–36 months). Objective cure rate was 93%. Subjectively only two patients have had recurrent symptoms of prolapse, and only 1 of these has required repeat surgery for cystocele. Mesh exposure vaginally occurred in 5 patients (6.5%); however all were treated with estrogen and/or local excision of exposed mesh and had no further sequelae. There were no incidences of chronic pain, infection, or abscess, and no patient required complete mesh removal for infection, pain, or extrusion. Conclusion. In select patients with anterior wall prolapse, repair with mesh augmentation via the transobturator route is a safe and effective procedure with up to 3 years of follow-up. PMID:19710939

Moore, Robert D.; Miklos, John R.

2009-01-01

52

A 3-D Finite Element Model of Anterior Vaginal Wall Support to Evaluate Mechanisms Underlying Cystocele Formation  

PubMed Central

Objectives To develop a 3D computer model of the anterior vaginal wall and its supports, validate that model, and then use it to determine the combinations of muscle and connective tissue impairments that result in cystocele formation, as observed on dynamic magnetic resonance imaging (MRI). Methods A subject-specific 3D model of the anterior vaginal wall and its supports was developed based on MRI geometry from a healthy nulliparous woman. It included simplified representations of the anterior vaginal wall, levator muscle, cardinal and uterosacral ligaments, arcus tendineus fascia pelvis and levator ani, paravaginal attachments, and the posterior compartment. This model was then imported into ABAQUS™ and tissue properties were assigned from the literature. An iterative process was used to refine anatomical assumptions until convergence was obtained between model behavior under increases of abdominal pressure up to 168 cmH2O and deformations observed on dynamic MRI. Results Cystocele size was sensitive to abdominal pressure and impairment of connective tissue and muscle. Larger cystocele formed in the presence of impairments in muscular and apical connective tissue support compared to either support element alone. Apical impairment resulted in a larger cystocele than paravaginal impairment. Levator ani muscle impairment caused a larger urogenital hiatus size, longer length of the distal vagina exposed to a pressure differential, larger apical descent and resulted in a larger cystocele size. Conclusions Development of a cystocele requires a levator muscle impairment, an increase in abdominal pressure, and apical and paravaginal support defects. PMID:19481208

Chen, Luyun; Ashton-Miller, James A.; DeLancey, John O.L.

2009-01-01

53

Abnormalities of early depolarization in patients with remote anterior myocardial infarction and ventricular septal hypoperfusion. Diagnosis of septal MI by BSM  

SciTech Connect

The authors conducted this study to find the difference in body surface isopotential maps in 46 patients with previous anterior infarction with and without septal involvement. Thallium-201 myocardial-perfusion imaging identified 25 patients with septal infarction (group P) and 21 without (group N). In contrast to group N, group P had a prominent minimum on the anterior chest during the early phases of the QRS. According to the results obtained, the following criteria for identifying patients with septal infarction (group P) were proposed (1). Criterion 1: The absolute value of the voltage of the minimum is equal to or greater than that of the maximum at 5 ms after the onset of the QRS; (2) Criterion 2: During the early portion of the QRS the voltage of the minimum reaches -0.10 mV at the same time or earlier than the maximum reaches 0.10 mV. Both criteria had higher sensitivities (100% and 100%), specificities (71.4% and 90.5%), and predictive accuracies (87.0% and 95.7%) than either Franklead vectorcardiograms or standard 12-lead electrocardiograms in the study population. Thus, body surface isopotential mapping is considered to be useful for the diagnosis of septal involvement in patients with previous anterior myocardial infarction.

Kubota, I.; Yamaki, M.; Ikeda, K.; Yamaguchi, I.; Tonooka, I.; Tsuiki, K.; Yasui, S. (Yamagata Univ. School of Medicine (Japan))

1990-10-01

54

Planar positron imaging of rubidium-82 for myocardial infarction: a comparison with thallium-201 and regional wall motion.  

PubMed

Rubidium-82 (Rb-82) is a generator-produced, short half-life (76 seconds) positron emitting potassium analog. Using a mobile gamma camera equipped with a rotating tungsten collimator and high-energy shielding, we examined the use of Rb-82 in the coronary care unit and clinical laboratory for detection of perfusion defects due to myocardial infarction. We studied 31 subjects, 10 patients with acute myocardial infarction, 12 with remote myocardial infarction, and nine controls. Rb-82 images were compared with Tl-201 and regional wall motion for detection of infarct-related arteries. Of the 22 patients with myocardial infarction, 16 were identified with Rb-82 and Tl-201. In nine control subjects, eight were normal with each method. Correlation between Rb-82 and Tl-201 defect scores was excellent. Sensitivity and specificity for infarct-related arteries were similar for Rb-82, Tl-201, and wall motion imaging. Thus planar Rb-82 imaging can detect MI reliably in the coronary care unit and in the clinical laboratory. PMID:2788983

Williams, K A; Ryan, J W; Resnekov, L; Stark, V; Peterson, E L; Gustafson, G C; Martin, W B; Freier, P A; Harper, P V

1989-09-01

55

Planar positron imaging of rubidium-82 for myocardial infarction: A comparison with thallium-201 and regional wall motion  

SciTech Connect

Rubidium-82 (Rb-82) is a generator-produced, short half-life (76 seconds) positron emitting potassium analog. Using a mobile gamma camera equipped with a rotating tungsten collimator and high-energy shielding, we examined the use of Rb-82 in the coronary care unit and clinical laboratory for detection of perfusion defects due to myocardial infarction. We studied 31 subjects, 10 patients with acute myocardial infarction, 12 with remote myocardial infarction, and nine controls. Rb-82 images were compared with Tl-201 and regional wall motion for detection of infarct-related arteries. Of the 22 patients with myocardial infarction, 16 were identified with Rb-82 and Tl-201. In nine control subjects, eight were normal with each method. Correlation between Rb-82 and Tl-201 defect scores was excellent. Sensitivity and specificity for infarct-related arteries were similar for Rb-82, Tl-201, and wall motion imaging. Thus planar Rb-82 imaging can detect MI reliably in the coronary care unit and in the clinical laboratory.

Williams, K.A.; Ryan, J.W.; Resnekov, L.; Stark, V.; Peterson, E.L.; Gustafson, G.C.; Martin, W.B.; Freier, P.A.; Harper, P.V. (Univ. of Chicago Pritzker School of Medicine, IL (USA))

1989-09-01

56

The primary percutaneous coronary intervention for acute anterior myocardial infarction in a middle-aged male patient with bilateral coronary artery to pulmonary artery fistulas.  

PubMed

A 38-year-old man admitted to emergency department with 2 h of typical substernal chest pain, shortness of breath and nausea. The ECG revealed sinus rhythm with a 3 mm ST elevation in precordial leads V1-V6. The coronary angiography revealed acute total occlusion in left anterior descending artery (LAD) with normal circumflex and right coronary artery (RCA) along with bilateral fistulas arising from the proximal LAD and ostial RCA draining into the main pulmonary artery. Therefore, primary percutaneous coronary intervention and bare metal stent implantation was performed to culprit LAD lesion. The electrocardiographically gated 64-slice multidetector-row CT showed two large, tortuous abnormal vessels which arose from the both ostial part of the RCA and LAD draining into the main pulmonary artery. We report an unusual case of bilateral coronary artery to pulmonary artery fistulas leading to acute anterior myocardial infarction in a middle-aged male patient. PMID:23152179

Altay, Servet; Cakmak, Huseyin Altug; Velibey, Yalcin; Erer, Betul

2012-01-01

57

Report of Three Cases of Unusual Anterior Abdominal Wall Defects in Fallujah General Hospital During the Year 2010  

PubMed Central

Abdominal wall defects occur when the normal sequence of the gastro intestinal tract development is interrupted. Gastroschisis represents a herniation of abdominal contents through a paramedian full-thickness abdominal wall fusion defect without involving the umbilical cord. Evisceration usually only contains intestinal loops and has no surrounding membrane unlike omphalocoele. It is unusual for a newborn with gastroschisis to have other serious birth defects. Neonates with gastroschisis have better prognosis than those with omphalocele. Very rarely is gastroschisis associated with herniation of other organs, and their presence makes the prognosis worse. I report three cases of unusual anterior abdominal wall defects during the year 2010, each having specific associated abnormalities. One was stillborn, and the other two died shortly after delivery. PMID:23864990

Alaani, Samira

2012-01-01

58

[Effect of ACE-inhibitors on left ventricular remodeling after acute anterior or posterior myocardial infarct. Cine- magnetic resonance tomography study].  

PubMed

The question whether patients with posterior infarctions (PMI) have a comparable benefit of an ACE-inhibitor therapy to those with anterior infarction (AMI) is still open. The study was undertaken to investigate the different influence of ACE inhibitors on the remodeling of the left ventricle after AMI or PMI. 52 patients (Pt.) (17 female, 38-73 years) were randomized to receive either 25-75 mg/day captopril (C) or 5-20 mg/day fosinopril (F) beginning on day 7 after acute myocardial infarction. 28 Pt. had AMI, 24 Pt. PMI. Infarct size was determined by the creatine kinase integral method. 50 Pt. were examined by cine magnetic resonance imaging 1 and 26 weeks after infarction. We determined: left ventricular end-diastolic (LVEDVI) and end-systolic (LVESVI) volume index, ejection fraction (EF), infarction weight (IW), left ventricular muscle mass (MM), systolic wall thickening (SWT) and motility (MOT) of the vital myocardium, and clinical behavior according to the guidelines of the New York Heart Association (NYHA). The results were compared with those of a sample (V) without ACE inhibitor therapy (10 females, 21 males, 36-75 years, 19 AMI, 12 PMI). There were no significant differences between C and F. Without ACE-inhibition therapy LVEDVI increased by 28.2% in AMI, by 18.4% in PMI (p < 0.001), with ACE-inhibition by 13.7% in AMI and by 9.9% in PMI (p < 0.001). LVESVI increased in V by 40.1% in AMI, by 28.5% in PMI (p < 0.001). With ACE-inhibitor we found an increase of 11.2% in AMI and 5.3% in PMI (p < 0.001). EF decreased without ACE-inhibitor by 18.7% in AMI and by 10.2% in PMI (p < 0.001), with ACE-inhibition increased by 4.3% in AMI and PMI, respectively (n. s.). NYHA got better in all groups, by 17.4% in AMI and 20.8% in PMI without ACE-inhibitor (n.s.), by 45.5% in AMI and 31.6% in PMI with ACE-inhibitor (p < 0.001). IG increased by 15.5% in AMI and 8.8% in PMI in V (p < 0.001), by 11.2% in AMI and 5.3% in PMI with C or F (p < 0.001). MM got bigger in V by 16.6% in AMI and 12.7% in PMI (p < 0.05), with ACE-inhibitor by 11.7% in AMI and 8.0% in PMI (p < 0.05). sWD increased by 12.9% in AMI and by 6.7% in PMI in V (p < 0.01), by 37.1% in AMI and 88.0% in PMI with C or F (p < 0.001). MOT decreased by 39.6% in AMI and 14.9% in PMI without ACE-inhibition (p < 0.001) and increased by 4.3% in AMI and by 5.0% in PMI with ACE-inhibitor (n. s.). All differences between V and the ACE-inhibitor groups were significant. Even patients with PMI clearly benefit from ACE-inhibitor therapy, but less than those with AMI. Captopril and fosinopril show no different effects after myocardial infarction. PMID:11008329

Konermann, M; Odenthal, H J; Altmann, C; Laschewski, F; Rawert, B; Trappe, H J; Sanner, B M

2000-01-01

59

Asymmetric evolution of anterior chest wall blood supply in female adolescents with progressive right-convex thoracic idiopathic scoliosis  

PubMed Central

Breast asymmetry was believed to be related to asymmetry of anterior chest wall blood supply and subsequently to aetiology of idiopathic thoracic scoliosis in female adolescents. Recent investigations on the anterior chest wall blood supply with Colour Doppler Ultrasonography (CDU) in such individuals did not show anatomical and hemodynamic abnormalities. The present study investigated the evolution of anterior chest wall blood supply in these individuals over a 2-year period. Twenty female adolescents with progressive right-convex idiopathic thoracic scoliosis (scoliotics), who were during the study in therapy with horacolumbosacral orthosis (TLSO) and 20 age-matched girls, without spine deformity (controls) were studied with CDU [internal mammary artery (IMA)] twice within the 2-year period. IMA-anatomical parameters [lumen diameter (D) and cross sectional area (AR)] as well as hemodynamic flow parameters [time average mean flow velocity and flow volume per minute (FV)] were measured. In the 2-year-period of observation, TLSO prevented scoliosis progression (P = 0.004), while IMA-AR decreased bilaterally in the individuals of both groups (P < 0.03). In the last evaluation: in scoliotics right IMA FV decreased (P < 0.04), while in controls IMA FV decreased bilaterally (P < 0.03); left IMA FV was significantly higher (P < 0.05) in scoliotics than in controls. The significant, within the 2-year period, decrease of IMA-diameter, cross-sectional area, and flow volume seems to be a physiological ageing process because it was observed in all individuals (scoliotics and controls), and thus these anatomic and hemodynamic changes seem not to have been affected by bracing. The maintenance of left flow volume of IMA in the pre-brace levels in scoliotics was the most significant finding of this investigation. In conclusion, this study provided evidence for abnormalities in the evolution of anterior chest wall blood supply in female adolescents with progressive right-convex female thoracic scoliosis. Further studies are needed to investigate if this asymmetric blood evolution contributes to the development of this pattern of scoliosis in girls. PMID:17294053

Iliopoulos, Panagiotis; Koureas, Georgios; Zacharatos, Spyridon; Stergiou, Panagiotis

2007-01-01

60

Texture analysis improves level set segmentation of the anterior abdominal wall  

SciTech Connect

Purpose: The treatment of ventral hernias (VH) has been a challenging problem for medical care. Repair of these hernias is fraught with failure; recurrence rates ranging from 24% to 43% have been reported, even with the use of biocompatible mesh. Currently, computed tomography (CT) is used to guide intervention through expert, but qualitative, clinical judgments, notably, quantitative metrics based on image-processing are not used. The authors propose that image segmentation methods to capture the three-dimensional structure of the abdominal wall and its abnormalities will provide a foundation on which to measure geometric properties of hernias and surrounding tissues and, therefore, to optimize intervention.Methods: In this study with 20 clinically acquired CT scans on postoperative patients, the authors demonstrated a novel approach to geometric classification of the abdominal. The authors’ approach uses a texture analysis based on Gabor filters to extract feature vectors and follows a fuzzy c-means clustering method to estimate voxelwise probability memberships for eight clusters. The memberships estimated from the texture analysis are helpful to identify anatomical structures with inhomogeneous intensities. The membership was used to guide the level set evolution, as well as to derive an initial start close to the abdominal wall.Results: Segmentation results on abdominal walls were both quantitatively and qualitatively validated with surface errors based on manually labeled ground truth. Using texture, mean surface errors for the outer surface of the abdominal wall were less than 2 mm, with 91% of the outer surface less than 5 mm away from the manual tracings; errors were significantly greater (2–5 mm) for methods that did not use the texture.Conclusions: The authors’ approach establishes a baseline for characterizing the abdominal wall for improving VH care. Inherent texture patterns in CT scans are helpful to the tissue classification, and texture analysis can improve the level set segmentation around the abdominal region.

Xu, Zhoubing [Electrical Engineering, Vanderbilt University, Nashville, Tennessee 37235 (United States)] [Electrical Engineering, Vanderbilt University, Nashville, Tennessee 37235 (United States); Allen, Wade M. [Institute of Imaging Science, Vanderbilt University, Nashville, Tennessee 37235 (United States)] [Institute of Imaging Science, Vanderbilt University, Nashville, Tennessee 37235 (United States); Baucom, Rebeccah B.; Poulose, Benjamin K. [General Surgery, Vanderbilt University Medical Center, Nashville, Tennessee 37235 (United States)] [General Surgery, Vanderbilt University Medical Center, Nashville, Tennessee 37235 (United States); Landman, Bennett A. [Electrical Engineering, Vanderbilt University, Nashville, Tennessee 37235 and Institute of Imaging Science, Vanderbilt University, Nashville, Tennessee 37235 (United States)] [Electrical Engineering, Vanderbilt University, Nashville, Tennessee 37235 and Institute of Imaging Science, Vanderbilt University, Nashville, Tennessee 37235 (United States)

2013-12-15

61

Geometric differences of the mitral valve tenting between anterior and inferior myocardial infarction with significant ischemic mitral regurgitation: quantitation by novel software system with transthoracic real-time three-dimensional echocardiography.  

PubMed

We sought to investigate the 3-dimensional geometric differences of mitral leaflet tenting in ischemic mitral regurgitation, comparing inferior and anterior myocardial infarction (MI). Using real-time 3-dimensional echocardiography, we obtained transthoracic volumetric images for patients with significant ischemic mitral regurgitation (9 inferior and 7 anterior). With our novel software system, 3-dimensional images of the leaflets were reconstructed for quantitation. Mitral leaflet configuration was then represented in contour in which the degree of the tenting could be observed. Calculated percent of tethered leaflet area (>5-mm tenting from the annular level) was compared in inferior and anterior MI. Percent of tethered leaflet area was significantly smaller in inferior than anterior MI, reflecting the localized leaflet tenting in inferior MI (16.7 +/- 18.8% vs 38.9 +/- 9.7%, P = .01). In anterior MI, mitral valve leaflets were widely tethered toward the left ventricle, in contrast with inferior MI showing localized tenting of the leaflet. PMID:16423672

Watanabe, Nozomi; Ogasawara, Yasuo; Yamaura, Yasuko; Yamamoto, Katsunori; Wada, Nozomi; Kawamoto, Takahiro; Toyota, Eiji; Akasaka, Takashi; Yoshida, Kiyoshi

2006-01-01

62

Electrocardiographic diagnosis of remote posterior wall myocardial infarction using unipolar posterior lead V9  

SciTech Connect

The accuracy of four electrocardiographic criteria for diagnosing remote posterior myocardial infarction was assessed prospectively in 369 patients undergoing exercise treadmill testing with thallium scintigraphy. Criteria included the following: (1) R-wave width greater than or equal to 0.04 s and R-wave greater than or equal to S-wave in V1; (2) R-wave greater than or equal to S-wave in V2; (3) T-wave voltage in V2 minus V6 greater than or equal to 0.38 mV (T-wave index); (4) Q-wave greater than or equal to 0.04 s in left paraspinal lead V9. Twenty-seven patients (7.3 percent) met thallium criteria for posterior myocardial infarction, defined as a persistent perfusion defect in the posterobase of the left ventricle. Sensitivities for the four criteria ranged from 4 to 56 percent, and specificities ranged from 64 to 99 percent. Posterior paraspinal lead V9 provided the best overall predictive accuracy (94 percent), positive predictive value (58 percent), and ability to differentiate patients with and without posterior myocardial infarction of any single criterion (p less than .0001). Combining the T-wave index with lead V9 further enhanced the diagnostic yield: the sensitivity for detecting posterior infarction by at least one of these criteria was 78 percent, and when both criteria were positive, specificity was 98.5 percent. It is concluded that a single, unipolar posterior lead in the V9 position is superior to standard 12-lead electrocardiographic criteria in diagnosing remote posterior myocardial infarction, and that combining V9 with the T-wave index maximizes the diagnostic yield.

Rich, M.W.; Imburgia, M.; King, T.R.; Fischer, K.C.; Kovach, K.L. (Jewish Hospital Washington University Medical Center, St. Louis (USA))

1989-09-01

63

Subacute left ventricle free wall rupture after acute myocardial infarction: awareness of the clinical signs and early use of echocardiography may be life-saving  

Microsoft Academic Search

Left ventricular free wall rupture (LVFWR) is a fearful complication of acute myocardial infarction in which a swift diagnosis and emergency surgery can be crucial for successful treatment. Because a significant number of cases occur subacutely, clinicians should be aware of the risk factors, clinical features and diagnostic criteria of this complication. We report the case of a 69 year-old

Luís Raposo; Maria João Andrade; Jorge Ferreira; Carlos Aguiar; Rute Couto; Miguel Abecasis; Nuno Jalles-Tavares; José Aniceto da Silva

2006-01-01

64

Functional maturation of the capillary wall in the fetal and neonatal rat heart: permeability characteristics of developing myocardial capillaries.  

PubMed

The development of the functional components of the myocardial capillary wall was characterized by time-course studies of transendothelial transport of intravascularly injected probes of graded size from 16 days of gestation in the fetal rat to seven days postpartum. Despite the morphological changes occurring in the developing endothelial cells, the interaction of the probes was similar throughout the developmental period studied. The carbon particles were retained within the capillary lumina without any association with interendothelial junctions or with plasmalemmal vesicles. Carbon also was associated with coated vesicles. In contrast to carbon, ferritin was localized sequentially, over 60 sec of circulation, in plasmalemmal vesicles on the lumenal surface, in the cytoplasm, and on the ablumenal surface of the endothelial cells as well as in the interstitial space. Ferritin was located also in coated pits and vesicles and, after 90 sec of circulation, in multivesicular bodies. Within 30 sec of circulation, reaction product of myoglobin was located in plasmalemmal vesicles, coated vesicles, and transendothelial cell channels. Also within 30 sec, myoglobin partially filled the interendothelial space from the capillary lumina to the level of the tight junction. At all developmental ages studied, the interendothelial cell junctions appeared structurally tight and were impermeable to all of the probes. Once ferritin or myoglobin had reached the ablumenal space, the basal lamina did not appear to restrain the passage of the probes. Plasmalemmal vesicles are the capillary structures which transendothelially transport ferritin and myoglobin in developing myocardial capillaries. PMID:3425560

Porter, G A; Bankston, P W

1987-12-01

65

Intrauterine left chamber myocardial infarction of the heart and hydrops fetalis in the recipient fetus due to twin-to-twin transfusion syndrome.  

PubMed

A rare complication of twin-to-twin transfusion syndrome (TTTS) is described: myocardial infarction of the recipient fetus. Myocardial infarction and hydrops are considered to be consequences of hypertension in the recipient. No other organs were affected. Pathological signs of intrauterine hypertension were estimated by the thickness of vessel walls and signs of hypertrophied myocardial cells. In the heart of the recipient fetus there was a chronic myocardial infarction near the apex cordis on the anterior wall with an aneurysm 4x5 mm in diameter. Diagnosis was based on light microscopic examination. The poor myocardial systolic function resulted in hydrops. Since the mother was administered beta sympathomimetics in therapeutic doses the contribution of the drug to the myocardial infarction is uncertain, but we would like to suggest this as a possible adverse effect in TTTS. The present case is the first reported myocardial infarction in connection with the syndrome. PMID:11920902

Marton, Tamás; Hajdú, Júlia; Hruby, Ervin; Papp, Zoltán

2002-03-01

66

Radionuclide imaging of myocardial infarction using Tc-99m TBI  

SciTech Connect

The cationic complex Tc-99m t-butylisonitrile (TBI) concentrates in the myocardial tissue of several animal species. Its myocardial distribution is proportional to blood flow both in zones of ischemia and in normal myocardium at rest. Planar, tomographic, and gated myocardial images have been obtained using Tc-99m TBI in the human. The authors investigated the potential application of Tc-99m TBI imaging to detect and localize myocardial infarction. Four subjects without clinical evidence of cardiovascular disease and five patients with ECG evidence of previous myocardial infarction were studied. Tc-99m TBI (10mCi) was injected intravenously with the patient in a resting state with planar imaging in the anterior, 30 and 70 degree LAO projections beginning one hr after injection. The distribution of the tracer was homogeneous throughout the left ventricular wall in the normal subjects. Regional perfusion defects were present in 4/5 of the patients with myocardial infarction. Location of the defects corresponded to the location of the infarct using ECG criteria (2 inferoposterior and 2 anterior). The patient in whom the Tc-99m TBI image appeared normal had sustained a subendocardial myocardial infarct which could not be localized by ECG; the other 4 pts had transmural infarcts. Anterior and 30 degree LAO images were of excellent quality in all cases; there was overlap of the liver on the inferior wall of the left ventricle on the 70 degree LAO views. The authors conclude that accurate perfusion imaging may be possible using Tc-99m TBI in patients with transmural myocardial infarction.

Holman, B.L.; Campbell, S.; Kirshenbaum, J.M.; Lister-James, J.; Jones, A.G.; Davison, A.; Antman, E.

1985-05-01

67

Left hepatic lobe herniation through an incisional anterior abdominal wall hernia and right adrenal myelolipoma: a case report and review of the literature  

PubMed Central

Introduction Herniation of the liver through an anterior abdominal wall hernia defect is rare. To the best of our knowledge, only three cases have been described in the literature. Case presentation A 70-year-old Mexican woman presented with a one-week history of right upper quadrant abdominal pain, nausea, vomiting, and jaundice to our Department of General Surgery. Her medical history included an open cholecystectomy from 20 years earlier and excessive weight. She presented with jaundice, abdominal distension with a midline surgical scar, right upper quadrant tenderness, and a large midline abdominal wall defect with dullness upon percussion and protrusion of a large, tender, and firm mass. The results of laboratory tests were suggestive of cholestasis. Ultrasound revealed choledocholithiasis. A computed tomography scan showed a protrusion of the left hepatic lobe through the anterior abdominal wall defect and a well-defined, soft tissue density lesion in the right adrenal topography. An endoscopic common bile duct stone extraction was unsuccessful. During surgery, the right adrenal tumor was resected first. The hernia was approached through a median supraumbilical incision; the totality of the left lobe was protruding through the abdominal wall defect, and once the lobe was reduced to its normal position, a common bile duct surgical exploration with multiple stone extraction was performed. Finally, the abdominal wall was reconstructed. Histopathology revealed an adrenal myelolipoma. Six months after the operation, our patient remains in good health. Conclusions The case of liver herniation through an incisional anterior abdominal wall hernia in this report represents, to the best of our knowledge, the fourth such case reported in the literature. The rarity of this medical entity makes it almost impossible to specifically describe predisposing risk factors for liver herniation. Obesity, the right adrenal myelolipoma mass effect, and the previous abdominal surgery are likely to have contributed to incisional hernia formation. PMID:22234036

2012-01-01

68

Characterization of PET partial volume corrections for variable myocardial wall thicknesses  

Microsoft Academic Search

Limited scanner resolution and cardiac motion contribute to partial volume (PV) averaging of positron emission tomography (PET) images. An extravascular (EV) density image, created from the subtraction of a blood pool (BP) from a transmission (TX) image can be used to estimate PV losses in the myocardium (MYO). A phantom emulating the left ventricle myocardium, with a variable wall thickness

Richard W. Wassenaar; Robert A. deKemp

2006-01-01

69

Characterization of PET partial volume corrections for variable myocardial wall thicknesses  

Microsoft Academic Search

Limited scanner resolution and cardiac motion contribute to partial volume (PV) averaging of PET images. An extravascular (EV) density image, created from the subtraction of a blood pool (BP) from a transmission (TX) image can be used to estimate PV losses in the myocardium (MYO). A phantom emulating the left ventricle myocardium, with a variable wall thickness (5 mm to

Richard W. Wassenaar; Robert A. deKemp

2004-01-01

70

Occipital (V6) and parietal (V6A) areas in the anterior wall of the parieto-occipital sulcus of the macaque: a cytoarchitectonic study  

Microsoft Academic Search

The anterior wall of the parieto-occipital sulcus (POs) of the macaque monkey, classically considered as part of Brodmann's area 19, contains two functionally distinct areas: a ventral, purely visual area, V6, and a dorsal area, V6A, containing visual neurons and neurons related to the control of arm movements. The aim of this study was to establish whether areas V6 and

Giuseppe Luppino; Suliann Ben Hamed; Michela Gamberini; Massimo Matelli; Claudio Galletti

2005-01-01

71

Myocardial metabolism, perfusion, wall motion and electrical activity in Duchenne muscular dystrophy  

SciTech Connect

The cardiomyopathy of Duchenne's muscular dystrophy originates in the posterobasal left ventricle and extends chiefly to the contiguous lateral wall. Ultrastructural abnormalities in these regions precede connective tissue replacement. We postulated that a metabolic fault coincided with or antedated the subcellular abnormality. Accordingly, regional left ventricular metabolism, perfusion and wall motion were studied using positron computed tomography and metabolic isotopes supplemented by thallium perfusion scans, equilibrium radionuclide angiography and M-mode and two-dimensional echocardiography. To complete the assessment, electrocardiograms, vectorcardiograms, 24 hour taped electrocardiograms and chest x-rays were analyzed. Positron computed tomography utilizing F-18 2-fluoro 2-deoxyglucose (FDG) provided the first conclusive evidence supporting the hypothesis of a premorphologic regional metabolic fault. Thus, cardiac involvement in duchenne dystrophy emerges as a unique form of heart disease, genetically targeting specific regions of ventricular myocardium for initial metabolic and subcellular changes. Reported ultrastructural abnormalities of the impulse and conduction systems provide, at least in part, a basis for the clinically observed sinus node, intraatrial, internodal, AV nodal and infranodal disorders.

Perloff, J.K.; Henze, E.; Schelbert, H.R.

1982-01-01

72

Anterior Myocardial Territory May Replace the Heart as Organ at Risk in Intensity-Modulated Radiotherapy for Left-Sided Breast Cancer  

SciTech Connect

Purpose: We investigated whether the heart could be replaced by the anterior myocardial territory (AMT) as the organ at risk (OAR) in intensity-modulated radiotherapy (IMRT) of the breast for patients with left-sided breast cancer. Methods and Materials: Twenty-three patients with left-sided breast cancer who received postoperative radiation after breast-conserving surgery were studied. For each patient, we generated five IMRT plans including heart (H), left ventricle (LV), AMT, LV+AMT, and H+LV as the primary OARs, respectively, except both lungs and right breast, which corresponded to IMRT(H), IMRT(LV), IMRT(AMT), IMRT(LV+AMT), and IMRT(H+LV). For the planning target volumes and OARs, the parameters of dose-volume histograms were compared. Results: The homogeneity index, conformity index, and coverage index were not compromised significantly in IMRT(AMT), IMRT(LV) and IMRT(LV+ AMT), respectively, when compared with IMRT(H). The mean dose to the heart, LV, and AMT decreased 5.3-21.5% (p < 0.05), 19.9-29.5% (p < 0.05), and 13.3-24.5% (p < 0.05), respectively. Similarly, the low (e.g., V5%), middle (e.g., V20%), and high (e.g., V30%) dose-volume of the heart, LV, and AMT decreased with different levels. The mean dose and V10% of the right lung increased by 9.2% (p < 0.05) and 27.6% (p < 0.05), respectively, in IMRT(LV), and the mean dose and V5% of the right breast decreased significantly in IMRT(AMT) and IMRT(LV+AMT). IMRT(AMT) was the preferred plan and was then compared with IMRT(H+LV); the majority of dose-volume histogram parameters of OARs including the heart, LV, AMT, both lungs, and the right breast were not statistically different. However, the low dose-volume of LV increased and the middle dose-volume decreased significantly (p < 0.05) in IMRT(AMT). Also, those of the right lung (V10%, V15%) and right breast (V5%, V10%) decreased significantly (p < 0.05). Conclusions: The AMT may replace the heart as the OAR in left-sided breast IMRT after breast-conserving surgery to decrease the radiation dose to the heart.

Tan Wenyong [Department of Radiotherapy, Hubei Cancer Hospital, Wuhan (China); Key Laboratory of Molecular Biophysics of the Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan (China); Liu Dong [Department of Radiotherapy, Hubei Cancer Hospital, Wuhan (China); Xue Chenbin [Key Laboratory of Molecular Biophysics of the Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan (China); Xu Jiaozhen; Li Beihui [Department of Radiotherapy, Hubei Cancer Hospital, Wuhan (China); Chen Zhengwang [Key Laboratory of Molecular Biophysics of the Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan (China); Hu Desheng [Department of Radiotherapy, Hubei Cancer Hospital, Wuhan (China); Wang Xionghong, E-mail: tanwyym@yahoo.com.cn [Department of Radiotherapy, Hubei Cancer Hospital, Wuhan (China)

2012-04-01

73

Effect of tapering internal coronal walls on fracture resistance of anterior teeth treated with cast post and core: In vitro study  

PubMed Central

When fabricating indirect post and core, internal coronal walls are tapered to remove undercuts and allow a better adaptation. To evaluate the fracture strength of anterior tooth reconstructed with post and core and crowned, with two different taper of internal coronal walls, 6° and 30° to the long axis, two groups of 30 clear plastic analogues simulating endodontically treated maxillary central incisors were prepared. The analogues crowned were subjected to a compressive load with a 1-kN cell at a crosshead speed of 0.05?mm/min at 130° to the long axis until fracture occurred. Data were analyzed by Lillifors and Mann–Whitney tests. Mean failure loads for the groups were as follows: group I 1038.69?N (standard deviation ±243.52?N) and group II 1231.86?N (standard deviation ±368.76?N). Statistical tests showed significant difference between groups (p?=?0.0010?walls appears to enhance the fracture resistance of anterior maxillary teeth post and core reconstructed. PMID:25342986

Eid, Rita; Homsy, Fodda; Elhusseini, Hasan

2014-01-01

74

Clinical characteristics and Thrombolysis In Myocardial Infarction frame counts in women with transient left ventricular apical ballooning syndrome  

Microsoft Academic Search

The characteristics of 16 women with transient left ventricular (LV) apical ballooning syndrome in a United States population are presented. Additionally, Thrombolysis In Myocardial Infarction (TIMI) frame counts were evaluated during the acute period. Patients generally presented with anterior ST-elevation acute coronary syndrome in the absence of obstructive coronary disease. All patients had LV apical wall motion abnormalities. An acute

Kevin A Bybee; Abhiram Prasad; Greg W Barsness; Amir Lerman; Allan S Jaffe; Joseph G Murphy; R. Scott Wright; Charanjit S Rihal

2004-01-01

75

The Association of Abnormal Ventricular Wall Motion and Increased Dispersion of Repolarization in Humans is Independent of the Presence of Myocardial Infarction  

PubMed Central

Abnormal ventricular wall motion is a strong clinical predictor of sudden, arrhythmic, cardiac death. Dispersion in repolarization is a prerequisite for the initiation of re-entrant arrhythmia. We hypothesize that regionally decreased wall motion is associated with heterogeneity of repolarization. We measured local activation times, activation-recovery intervals (ARIs, surrogate for action potential duration), and repolarization times using a multielectrode grid at nine segments on the left ventricular epicardium in 23 patients undergoing coronary artery surgery. Regional wall motion was simultaneously assessed using intraoperative transesophageal echocardiography. Three groups were discriminated: (1) Patients with normal wall motion (n?=?11), (2) Patients with one or more hypokinetic segments (n?=?6), (3) Patients with one or more akinetic or dyskinetic segments (n?=?6). The average ARI was similar in all groups (251?±?3.7?ms, ±SEM). Dispersion of ARIs between the nine segments was significantly increased in the hypokinetic (84?±?7.4?ms, p?myocardial infarction. Repolarization heterogeneity occurred primarily in the normally contracting regions of the hearts with abnormal wall motion. An almost maximal increased dispersion of repolarization was observed when there was only a single hypokinetic segment. We conclude that inhomogeneous wall motion abnormality of even moderate severity is associated with increased repolarization inhomogeneity, independent from the presence of infarction. PMID:22783201

Opthof, Tobias; Sutton, Peter; Coronel, Ruben; Wright, Susan; Kallis, Panny; Taggart, Peter

2012-01-01

76

Treatment of a chronic vesicocutaneous fistula and abdominal wall defect after resection of a soft tissue sarcoma using a bipedicled latissimus dorsi and serratus anterior free flap.  

PubMed

We present a surgical treatment for bladder reconstruction in a case of chronic vesicocutaneous radiation-induced fistula and reconstruction of the abdominal wall after resection of a liposarcoma in the rectus abdominis muscle. Fistulas are sequelae after radiotherapy. To regain bladder function and reconstitute abdominal wall stability, a microsurgical flap approach should be considered. A male patient underwent resection of a liposarcoma in the rectus abdominis muscle with adjuvant radiotherapy, suffering from a chronic vesicocutaneous fistula. A bipedicled combined latissimus dorsi and serratus anterior flap was carried out after resection of the fistula for reconstruction of the urine bladder and the abdominal wall. Ascending urethrography 4 weeks postoperatively showed no leakage. In the 4-month follow-up period, no signs of recurrence of the fistula or herniation occurred. A bipedicled flap allowed reconstruction of the urine bladder and the abdominal wall. Using non-irradiated, well-perfused intra-abdominal muscle tissue over the urine bladder prevented recurrence of the fistula. PMID:25040066

Ludolph, Ingo; Apel, Hendrik; Horch, Raymund E; Beier, Justus P

2014-11-01

77

[Economical and social effectiveness of one day surgical treatment in patients with hernial defects of anterior abdominal wall - results of 7 year study].  

PubMed

A hernia is a protrusion of a tissue, structure or part of a organ through the muscular tissue or the membrane by which it is normally contained. Most frequently hernial deffect is seen in anterior abdominal wall. Usually contents of hernial sac are abdominal organs or portion of organs. Hernia is classified according to the operating methods combining with type and grading of hernia. Recent surgical treatment of hernia can be divided in to 3 major groups: 1) Hernioplasty with double breasting techniques ( Bassini, McVay, Schouldice, Halsted). 2) Hernioplasty using tension free techniques (Lichtenstein, Gilbert-Rutkow). 3) Laparoscopic hernioplasty. One day surgery is a diagnostic and operative procedure in hospitalized patients in a single day, without night stay in hospital. PMID:18461034

Iar?mov, N; Ko?chev, A; Angelov, K; Velev, G; Todorov, G; Ilinov, V; Sedloev, T; Toshev, S; Gribnev, P

2007-01-01

78

High density of prostaglandin E2 binding sites in the anterior wall of the 3rd ventricle: a possible site of its hyperthermic action.  

PubMed

Prostaglandin E2 (PGE2) exerts a potent hyperthermic action when injected into the preoptic-hypothalamic area (POHA) and is considered to be a central mediator of fever. To determine the exact functional sites of PGE2, we used in vitro quantitative autoradiography of [3H]PGE2 binding sites in the rat POHA. The highest density of [3H]PGE2 binding was found in the regions of the anterior wall of the 3rd ventricle (A3V). Within the A3V, binding density was especially high in regions closest to the third ventricle or surrounding the organum vasculosum laminae terminalis (OVLT) but was relatively low within the OVLT itself. It seems likely that the A3V PGE2 binding sites identified in this study are responsible for PGE2 mediation of fever. PMID:1964828

Matsumura, K; Watanabe, Y; Onoe, H; Watanabe, Y; Hayaishi, O

1990-11-12

79

Anaesthetic modification of regional myocardial functional adjustments during myocardial ischaemia: halothane vs fentanyl.  

PubMed

During myocardial ischaemia, functional compensation occurs by non-ischaemic regions of the left ventricle (LV). Anaesthetics may affect compensation by altering contractility, metabolism and perfusion. This was studied in dogs anaesthetized with fentanyl (150 micrograms kg-1 loading dose and 100 micrograms kg-1 h-1) or 0.75% and 1.5% halothane and subjected to left anterior descending artery (LAD) occlusion. After 15 min of anterior wall ischaemia, cardiac output, mean arterial pressure and LV maximum dP/dt were diminished in the 1.5% halothane but not in the 0.75% halothane or fentanyl groups. In all groups, stroke volume decreased, LV end-diastolic pressure increased and anterior wall function deteriorated (measured as systolic shortening, peak systolic intramyocardial pressure (IMP), regional wall stroke work (RSW) and slope of preload recruitable stroke work curve (Mw)) with ischaemia. Functional changes in the lateral (non-ischaemic) wall were different between groups. Regional function during occlusion in this area improved with fentanyl (mean (SEM) IMP, RSW and Mw increased by 23 (2)%, 37 (3)% and 69 (7)%, respectively), was relatively well maintained with 0.75% halothane and diminished with 1.5% halothane. PMID:1547053

Kim, Y D; Danchek, M; Myers, A K; Burke, T A; Analouei, A; Miller, D L; Moore, S; Coughlin, S; Visner, M S

1992-03-01

80

Biphasic thallium 201 SPECT-imaging for the noninvasive diagnosis of myocardial perfusion abnormalities in a child with Kawasaki disease--a case report  

SciTech Connect

The mucocutaneous lymph node syndrome (Kawasaki disease) is of increasing importance for the pediatric cardiologist, for coronary aneurysms with the potential of thrombosis and subsequent stenosis can develop in the course of the disease. The authors report a 2 1/2-year-old female child in whom, fourteen months after the acute phase of Kawasaki disease, myocardial infarction occurred. Biphasic thallium 201 SPECT-imaging using dipyridamole depicted anterior wall ischemia and inferolateral infarction. This case demonstrates that noninvasive vasodilation-redistribution thallium 201 SPECT-imaging has the potential to predict reversible myocardial perfusion defects and myocardial necrosis, even in small infants with Kawasaki disease.

Hausdorf, G.; Nienaber, C.A.; Spielman, R.P.

1988-02-01

81

Magnesium deficiency prolongs myocardial stunning in an open-chest swine model.  

PubMed

The effect of magnesium deficiency on postischemic myocardial dysfunction (myocardial stunning) in an open-chest swine model was studied. Twelve swine were assigned either to low magnesium diet or control diet. Myocardial stunning was assessed by measuring regional wall thickening by epicardial Doppler before and after brief occlusion (8 min) of the left anterior descending coronary artery. Serum magnesium levels decreased significantly in the experimental group only. Glutathione levels were 42.6% lower in the magnesium deficient swine than in controls. Stunning time was significantly prolonged from 32.8 +/- 3.1 min in the control group to 43.8 +/- 4.6 min in the hypomagnesemic swine. In conclusion, magnesium deficiency is associated with prolonged recovery from myocardial stunning. PMID:7721477

Herzog, W R; Atar, D; Mak, I T; Alyono, D; MacCord, C; Weglicki, W B

1994-12-01

82

Peritoneal fluid causing inferior attenuation on SPECT thallium-201 myocardial imaging in women  

SciTech Connect

On SPECT thallium images, myocardial left ventricular (LV) anterior wall attenuation due to breast tissue is common in women. In contrast, in men, inferior wall counts are normally decreased compared to anterior counts. The purpose of this report is to describe cases of inferior wall attenuation of counts in women caused by peritoneal fluid, not myocardial disease. Twelve consecutive SPECT thallium myocardial studies performed in women on peritoneal dialysis, being evaluated for kidney transplant, were included in this study. For all studies, 3.5 mCi 201Tl were injected intravenously. Thirty-two images were acquired over 180 degrees (45 degrees RAO progressing to 45 degrees LPO) at 40 sec per stop. SPECT images were reviewed in short axis, horizontal long and vertical long axes. Data were also displayed in bullseye format with quantitative comparison to gender-matched normal files. Ten of 12 female patients studied had inferior wall defects on images, confirmed by bullseye display. All patients had approximately 2 liters of peritoneal fluid. Review of planar rotational views showed diaphragm elevation and fluid margin attenuations affecting left ventricular inferior wall. Thus, peritoneal fluid is a cause of inferior attenuation on 201Tl cardiac imaging.

Rab, S.T.; Alazraki, N.P.; Guertler-Krawczynska, E.

1988-11-01

83

Cardiogenic shock accompanied by dynamic left ventricular outflow tract obstruction and myocardial bridging after transient complete atrioventricular block mimicking ST-elevation myocardial infarction: a case report  

PubMed Central

Background Dynamic left ventricular outflow tract obstruction with or without mitral regurgitation is typically observed in hypertrophic cardiomyopathy, but is also occasionally seen without left ventricular hypertrophy. In this report, we present a case of cardiogenic shock that mimics ST-elevation myocardial infarction, due to dynamic left ventricular outflow tract obstruction with transient mitral regurgitation and myocardial bridging after transient complete atrioventricular block. Case presentation A 65-year-old man with hypertension presented himself at the emergency department with syncope after chest pain. His initial electrocardiography showed inferior ST elevation with profound precordial ST depression and transient complete atrioventricular block. Due to sustained hypotension, an intra-aortic balloon pump was applied. His coronary angiography revealed almost normal right coronary artery and left circumflex artery and only a severe myocardial bridge in the mid-segment of his left anterior descending artery. Instead, severe mitral regurgitation was found without regional wall motion abnormality both in the left ventriculography and the portable echocardiography. However the severe mitral regurgitation completely disappeared in follow up echocardiography the day after. The pressure gradient across the left ventricular outflow tract was measured at 8.95 mmHg during the resting state, and was increased to 38.95 mmHg during the Valsalva state. Conclusions The patient presented with a case of cardiogenic shock that mimicked ST-elevation myocardial infarction due to dynamic left ventricular outflow tract obstruction combined with myocardial bridging in the mid-left anterior descending artery. PMID:24252345

2013-01-01

84

Regional wall thickening of left ventricle evaluated by gated positron emission tomography in relation to myocardial perfusion and glucose metabolism  

SciTech Connect

Regional wall thickening was assessed by electrocardiographically gated positron emission tomography (ECG-gated PET) in 26 patients with coronary artery disease. The standardized percent count increase from end-diastole to end-systole (S-percent Cl) was calculated as an index of wall thickening. The S-percent Cl was 77.8% +/- 28.9% in the segments with normal perfusion at rest, 51.9% +/- 29.5% in those with mild hypoperfusion, and 32.8% +/- 30.9% in those with severe hypoperfusion (p less than 0.001, each). Among the segments with resting hypoperfusion, the S-percent Cl was 38.9% +/- 31.5% in those without stress-induced ischemia and 48.7% +/- 30.9% in those with ischemia (p less than 0.05). Furthermore, among resting severe hypoperfusion, the S-percent Cl was 23.0% +/- 23.9% in the segments without fluorine-18-fluorodeoxyglucose (FDG) uptake and 37.8 +/- 32.9% in those with FDG uptake (p less than 0.05). These results suggest that stress-induced ischemia and FDG accumulation correlated with wall thickening. Thus, quantitative analysis of regional wall thickening seems to be useful for combined analysis of regional function, perfusion and metabolism in coronary patients.

Yamashita, K.; Tamaki, N.; Yonekura, Y.; Ohtani, H.; Magata, Y.; Nohara, R.; Kambara, H.; Kawai, C.; Ban, T.; Konishi, J. (Kyoto Univ. (Japan))

1991-04-01

85

Measurement of regional myocardial blood flow in hypertrophic cardiomyopathy: Application of the first-pass flow model using ( sup 13 N)ammonia and PET  

SciTech Connect

Positron emission tomography (PET) has become an important tool in the study of regional myocardial blood flow. The purpose of the present study was to measure regional myocardial blood flow using dynamic ({sup 13}N)ammonia PET and the first-pass flow model. Thirteen patients with hypertrophic cardiomyopathy, and with a considerably thickened ventricular wall (25 mm or greater), were selected for the study in order to minimize errors due to spillover of radioactivity from blood to the myocardium and to the underestimation of myocardial activity caused by the partial volume effect. Arterial input function was determined by assigning a region of interest to the left atrial cavity on the PET images. Using left atrial and myocardial time-activity curves, regional myocardial blood flow was calculated using the first-pass flow model. Mean myocardial blood flow ranged from 47.8 to 76.5 ml/min per 100 g (63.0 +/- 9.4). Regional myocardial blood flow in the septum was significantly lower than in the anterior and lateral walls of the left ventricle (P less than .01). These results indicate the potential usefulness of dynamic PET in the measurement of regional myocardial blood flow in man.

Yoshida, K.; Endo, M.; Himi, T.; Kagaya, A.; Masuda, Y.; Inagaki, Y.; Fukuda, H.; Iinuma, T.; Yamasaki, T.; Fukuda, N. (Chiba Univ. School of Medicine (Japan))

1989-01-01

86

Myocardial Bridge  

MedlinePLUS

... surface of the heart. What is a myocardial bridge? A myocardial bridge is a band of heart muscle that lies ... artery, instead of underneath it. With a myocardial bridge, part of a coronary artery dips into and ...

87

Precordial ST segment depression during acute inferior myocardial infarction: early thallium-201 scintigraphic evidence of adjacent posterolateral or inferoseptal involvement  

SciTech Connect

To investigate the myocardial perfusion correlates of precordial ST segment depression during acute inferior myocardial infarction, a rest thallium-201 scintigram and a closely timed 12 lead electrocardiogram were obtained within 6 hours of the onset of infarction in 44 patients admitted with their first acute inferior myocardial infarction. Thirty-six patients demonstrated precordial ST segment depression (group 1) and eight did not (group 2). A perfusion defect involving the inferior wall was present in all 44 patients. Additional perfusion defects of the adjacent posterolateral wall (n . 20), the ventricular septum (n . 9) or both (n . 6) were present in 35 of 36 patients from group 1 compared with only 1 of 8 patients from group 2 (p less than 0.001). There was no significant difference in the frequency of multivessel coronary artery disease or disease of the left anterior descending artery between group 1 and group 2 or between patients with and those without a thallium-201 perfusion defect involving the ventricular septum. Thus, precordial ST segment depression during an acute inferior myocardial infarction is associated with thallium-201 scintigraphic evidence of more extensive involvement of the adjacent posterolateral or inferoseptal myocardial segments, which probably reflects the extent and pattern of distribution of the artery of infarction, rather than the presence of coexistent multivessel coronary artery disease or disease of the left anterior descending artery.

Lew, A.S.; Weiss, A.T.; Shah, P.K.; Maddahi, J.; Peter, T.; Ganz, W.; Swan, H.J.; Berman, D.S.

1985-02-01

88

Survival following self-limited left ventricular free wall rupture during myocardial infarction. Management differences between patients with or without pseudoaneurysm formation.  

PubMed

The clinical, angiographic and therapeutic features of eight patients who developed a left ventricular pseudoaneurysm (PA) after an acute myocardial infarction (AMI) and those of 25 who did not develop this complication following a medically managed left ventricular free wall rupture (FWR) were compared. These 25 patients were treated with pericardiocentesis, extended rest and strict blood pressure control. Most patients with FWR or PA had a first AMI and absence of overt heart failure. Both groups had a comparable age, frequency of systemic hypertension and extent of coronary disease. Pericardial effusion (> or =10 mm) was documented in all patients with FWR and in two of the three with PA with this information. Twenty four patients with FWR were hospitalized within the first 48 h (96%) but only three of those with PA (37.5%, P<0.002). Moreover, in patients with PA, a FWR was not suspected during AMI and, as opposed to those with FWR, they did not undergo a strict blood pressure control or a restriction of physical activity following AMI. Also, beta blockers were administered to 15 patients with FWR (60%) but to only one with PA (11%, P<0.02). Our findings suggest that failure to recognise a self limited FWR during AMI and to provide adequate control of blood pressure and physical exercise during the acute phase and the early weeks postinfarction, are likely to favor development of PA. PMID:11461727

Figueras, J; Cortadellas, J; Domingo, E; Soler-Soler, J

2001-07-01

89

Noninvasive stress testing of myocardial ischemia: comparison of GRE-MRI perfusion and wall motion analysis to 99 mTc-MIBI-SPECT, relation to coronary angiography  

Microsoft Academic Search

.   In the evaluation of ischemic heart disease only MR imaging seems to have the potential to assess myocardial perfusion, function,\\u000a and coronary morphology on a single instrument. The aim of this study was to assess the feasibility of a stress test with\\u000a dipyridamole (0.56 mg\\/kg) to analyze myocardial perfusion by Gd first-pass enhancement in ultrafast gradient-recalled-echo\\u000a MRI (perf-MRI), and

J. Bremerich; P. Buser; G. Bongartz; J. Müller-Brand; C. Grädel; M. Pfisterer; W. Steinbrich

1997-01-01

90

Infarct Size as Predictor of Systolic Functional Recovery after Myocardial Infarction  

PubMed Central

Background The effects of modern therapy on functional recovery after acute myocardial infarction (AMI) are unknown. Objectives To evaluate the predictors of systolic functional recovery after anterior wall AMI in patients undergoing modern therapy (reperfusion, aggressive platelet antiaggregant therapy, angiotensin-converting enzyme inhibitors and beta-blockers). Methods A total of 94 consecutive patients with AMI with ST-segment elevation were enrolled. Echocardiograms were performed during the in-hospital phase and after 6 months. Systolic dysfunction was defined as ejection fraction value < 50%. Results In the initial echocardiogram, 64% of patients had systolic dysfunction. Patients with ventricular dysfunction had greater infarct size, assessed by the measurement of total and isoenzyme MB creatine kinase enzymes, than patients without dysfunction. Additionally, 24.5% of patients that initially had systolic dysfunction showed recovery within 6 months after AMI. Patients who recovered ventricular function had smaller infarct sizes, but larger values of ejection fraction and E-wave deceleration time than patients without recovery. At the multivariate analysis, it can be observed that infarct size was the only independent predictor of functional recovery after 6 months of AMI when adjusted for age, gender, ejection fraction and E-wave deceleration time. Conclusion In spite of aggressive treatment, systolic ventricular dysfunction remains a frequent event after the anterior wall myocardial infarction. Additionally, 25% of patients show functional recovery. Finally, infarct size was the only significant predictor of functional recovery after six months of acute myocardial infarction. PMID:25004416

Minicucci, Marcos F.; Farah, Elaine; Fusco, Danieliso R.; Cogni, Ana Lucia; Azevedo, Paula S.; Okoshi, Katashi; Zanati, Silmeia G.; Matsubara, Beatriz B.; Paiva, Sergio A. R.; Zornoff, Leonardo A. M.

2014-01-01

91

The effect of volume currents due to myocardial anisotropy on body surface potentials.  

PubMed

Changes in anterior and posterior body surface potential maps (BSPMs) due to myocardial anisotropy were examined using a highly heterogeneous finite element model of an adult male subject constructed from segmented magnetic resonance images. A total of 23 different tissue types were identified in the whole torso. The myocardial fibre orientations in the human heart wall were mapped from the fibre orientations of a canine heart which are available in the literature using deformable mapping techniques. The current and potential distributions in the whole torso were computed using dipolar sources in the septum, apical area, left ventricular wall or right ventricular wall. For each dipole x, y, z orientations were studied. An adaptive finite element solver was used to compute currents and potential distributions in the whole torso with an element size of 0.78 x 0.78 x 3 mm in the myocardium and larger elements in other parts of the torso. For each dipole position two cases were studied. In one case the myocardium was isotropic and in the other it was anisotropic. It was found that BSPMs showed a very notable difference between the isotropic and the anisotropic myocardium for all dipole positions with the largest difference for the apical dipoles. The correlation coefficients for the BSPMs between the isotropic and anisotropic cases ranged from 0.83 for an apical dipole to 0.99 for an RV wall dipole. These results suggest that myocardial fibre anisotropy plays an important role in determining the body surface potentials. PMID:11996062

Ramon, Ceon; Schimpf, Paul; Wang, Yanqun; Haueisen, Jens; Ishimaru, Akira

2002-04-01

92

Rare case of Bland White-Garland syndrome with myocardial infarction in paediatrics.  

PubMed

A 3.5 months old female infant presented with acute history of loose motions, fever and irritability for 5 days. The infant had history of respiratory distress since birth that exaggerated while feeding along with sweating and increased milk intake. Patient had poor weight gain. On investigations she was found to have anomalous origin of the left coronary artery from the left pulmonary artery (ALCAPA) with dilated cardiomyopathy and anterior wall myocardial infarction which is a very rare diagnosis in paediatrics and very rare condition diagnosed in our settings. PMID:25226755

Saleem, Munnaza; Shah, Syed Sajid Hussain; Mehmood, Tahir

2013-01-01

93

Myocardial Infarction and Functional Outcome Assessment in Pigs  

PubMed Central

Introduction of newly discovered cardiovascular therapeutics into first-in-man trials depends on a strictly regulated ethical and legal roadmap. One important prerequisite is a good understanding of all safety and efficacy aspects obtained in a large animal model that validly reflect the human scenario of myocardial infarction (MI). Pigs are widely used in this regard since their cardiac size, hemodynamics, and coronary anatomy are close to that of humans. Here, we present an effective protocol for using the porcine MI model using a closed-chest coronary balloon occlusion of the left anterior descending artery (LAD), followed by reperfusion. This approach is based on 90 min of myocardial ischemia, inducing large left ventricle infarction of the anterior, septal and inferoseptal walls. Furthermore, we present protocols for various measures of outcome that provide a wide range of information on the heart, such as cardiac systolic and diastolic function, hemodynamics, coronary flow velocity, microvascular resistance, and infarct size. This protocol can be easily tailored to meet study specific requirements for the validation of novel cardioregenerative biologics at different stages (i.e. directly after the acute ischemic insult, in the subacute setting or even in the chronic MI once scar formation has been completed). This model therefore provides a useful translational tool to study MI, subsequent adverse remodeling, and the potential of novel cardioregenerative agents. PMID:24796715

Koudstaal, Stefan; Jansen of Lorkeers, Sanne J.; Gho, Johannes M.I.H.; van Hout, Gerardus P.J; Jansen, Marlijn S.; Grundeman, Paul F.; Pasterkamp, Gerard; Doevendans, Pieter A.

2014-01-01

94

Biocement--a new material. Results of its experimental use for osseous repair of skull cap defects with lesions of the dura mater and liquorrhea, reconstruction of the anterior wall of the frontal sinuses and fixation of alloimplants.  

PubMed

A newly developed material, which we call biocement, consisting of bisphenol-a-glycidyl methacrylate ("epoxide methacrylate') as organic matrix and Bioceramic Battelle, Bioglass Hench and/or pentacalcium hydroxide triphosphate ("tri-calcium phosphate') powder as filling particles is presented. In an extension of previous experiments, various types of this biocement, containing different admixtures of particulate matter, were employed to test their usefulness in head surgery, in particular maxillo-facial reconstruction, on dogs and a rhesus monkey. Encouraging results were obtained with regard to (a) fixing a titanium alloimplant under some degree of mechanical stress; (b) covering a defect in the skull cap, including the closure of an artificially induced meningeal fistula with liquorrhea; and (c) reconstruction of defects in the anterior wall of frontal sinuses. Special emphasis is placed on direct contact between biocement and bone, interdigitations between these two, reactions of meningeal tissue, and regeneration of ciliated epithelium underneath fixed reimplants over the frontal sinus. PMID:6216717

Raveh, J; Stich, H; Schawalder, P; Ruchti, C; Cottier, H

1982-01-01

95

Giant lateral left ventricular wall aneurysm sparing the submitral apparatus  

PubMed Central

Left ventricular aneurysms are a frequent and serious complication following acute transmural myocardial infarction and are most commonly located at the ventricular apex. The majority of these patients presents with severe mitral insufficiency, congestive heart failure, systemic embolism and sudden cardiac death. Giant aneurysms occurring in a submitral position between anterior and posterior papillary muscles on the lateral ventricular wall constitute a minor entity and those leaving the mitral apparatus intact are extremely rare. Herein, we report the case of a 57 y/o Caucasian male patient with a past medical history of coronary artery disease and myocardial infarction with a giant left ventricular aneurysm measuring 15x10x8 cm in diameter. Despite the size of the aneurysm and its close topographical relation to the posterior mitral annulus the mitral apparatus was intact with a competent valve and normal left atrial size. He underwent successful surgical ventricular restoration. PMID:24172071

2013-01-01

96

Myocardial infarction in young adults-risk factors and pattern of coronary artery involvement  

PubMed Central

Background: Coronary artery disease (CAD) mostly occurs in persons older than 45 years of age. In India, CAD manifests almost a decade earlier than in Western countries. This study was done to study the risk factors and angiographic profile in young patients presenting with acute myocardial infarction (AMI). Patients and Methods: One hundred and twenty four consecutive patients presenting with AMI at less than 40 years of age were studied for risk factors. Coronary angiography was done in all. Results: Out of 124 patients, 123 were male. Mean age was 35.94 ± yrs. One hundred and eighteen had ST elevation myocardial infarction (MI) (95.16%) and six had non ST elevation MI (5.84%). Anterior wall MI was present in 88 patients (70.97%), inferior wall MI in 31 patients (25%) and lateral wall MI in five patients (4.03%). Seventy three patients (58.8%) were smoker, 55 were hypertensive (44.35%), 10 were diabetic (8.06%). Family history of CAD was present in 22 (17.7%) patients. Low High-density lipoprotein (HDL) was seen in 53 patients (42.7%), and high triglycerides in 60 patients (48.38%). Significant CAD was found in 88 (70.96%) patients, 13 (10.48%) had normal coronaries. Single vessel disease was seen in 57 patients, two-vessel disease in 15 patients and three-vessel disease in eight patients. Total 125 lesions were seen and left anterior descending (LAD) was the commonest vessel involved, with 78 lesions (62.4%). Conclusion: AMI in young almost exclusively occurs in male, and ST elevation MI is the main presentation. Anterior wall MI is most common, with LAD being involved in around 2/3 patients. Smoking, hypertension, low HDL and high triglycerides are the major risk factors. PMID:24970969

Bhardwaj, Rajeev; Kandoria, Arvind; Sharma, Rajesh

2014-01-01

97

Myocardial temperature variation: effect on regional function and coronary flow in dogs  

SciTech Connect

Incremental changes in the temperature (28-42.5/sup 0/C) of the anterior left ventricular wall in a canine, working, beating right heart bypass preparation (constant preload, afterload, and heart rate) were produced to measure the effect of regional temperature on myocardial function and blood flow. Circumferential-axis segment lengths were measured with sonomicrometry in both the temperature-varied, left-anterior descending coronary artery (LAD)-supplied myocardium and the normothermic (38/sup 0/C) circumflex-supplied myocardium. Fast thermistors (time constant <0.25 s) continuously monitored midmyocardial temperature in both areas. A Silastic loop with heat exchanger, thermistors, strain gauge, and flow probe was inserted into the LAD and allowed precise control of regional myocardial temperature. Nine-micron radiolabeled microspheres injected into left atrium were used to evaluate coronary flow and distribution. In six anesthetized dogs, relative to normothermic control (38/sup 0/C), regional systolic shortening decreased 42.2 +/- 10% at 41/sup 0/C and increased 23.3 +/- 6% at 31/sup 0/C. There was no significant change in coronary blood flow or distribution at the three temperatures. Pressure-length areas varied inversely with myocardial temperature. These data demonstrate that there is a reversible inverse relationship between midwall T and ventricular function when heart rate, preload, and afterload are controlled.

D'Ambra, M.N.; Magrassi, P.; Lowenstein, E.; Kyo, S.; Austen, W.G.; Buckley, M.J.; LaRaia, P.J.

1987-02-01

98

Kinetics and imaging of /sup 111/In-labeled autologous platelets in experimental myocardial infarction  

SciTech Connect

The kinetics of accumulation and the external imaging patterns of /sup 111/In-labeled platelets infused in a dog model of left anterior descending coronary artery occlusion with reperfusion were studied. The effects of infarct age and regional residual myocardial blood flow upon platelet accumulation were quantified, and the capacity of /sup 111/In platelets to image the experimental infarction was evaluated qualitatively. The endocardial accumulation of /sup 111/In platelets occurred primarily in infarct zones with residual blood flow less than 0.6 times normal and was maximal (24.98 +/- 2.76 times normal) in the lowest blood flow zone (less than 0.1 times normal). Indium-111 platelet accumulation in the epicardium occurred in the regions with blood flow less than 0.6 times normal and was maximal (17.83 +/- 1.20 times normal) in the lowest blood flow zone (less than 0.1 times normal). The maximal endocardial and epicardial platelet accumulation occurred 24 hours after reperfusion and was significantly decreased at 48 hours. In vivo cardiac images revealed discrete areas of increased myocardial radioactivity uptake in the anterior wall of dogs 24 hours after reperfusion. All images 48 hours after reperfusion were negative. Thus, in the experimental setting, /sup 111/In platelets allow quantification of platelet accumulation after myocardial infarction at a tissue level and provide a noninvasive means of in vivo imaging of reperfused infarcted myocardium.

Laws, K.H.; Clanton, J.A.; Starnes, V.A.; Lupinetti, F.M.; Collins, J.C.; Oates, J.A.; Hammon, J.W. Jr.

1983-01-01

99

Myocardial protection.  

PubMed

Early studies of myocardial protection were designed to minimize ischemic injury. The next class and generation of investigations will most likely be designed to accelerate recovery following known myocardial injury. Such techniques will play an important role in allowing operations on acutely injured and ischemic myocardium and will be important in the treatment of postischemic injury when such injury occurs during the course of complex cardiac operations. Surgical aspects of myocardial metabolism are still rudimentary and many empiric observations require further exploration into the mechanisms by which such applications work. PMID:2979926

Wechsler, A S; Abd-Elfattah, A S; Murphy, C E; Salter, D R; Brunsting, L A; Goldstein, J P

1986-09-01

100

Relation of Opium Addiction with the Severity and Extension of Myocardial Infarction and Its Related Mortality  

PubMed Central

Background Despite some evidences about protective or triggering role of opium use in patients with coronary artery disease, the exact role of opium is still under question. The current study aimed to address the relation of opium dependence on the severity and extension of myocardial infarction (MI) and its related mortality. Methods The study population consisted of 460 consecutive patients (239 opium addicts and 221 non-addicts) with first acute MI. Study information was extracted from hospital recorded files as well as face to face interview. Findings In-hospital mortality in opium addicted patients was numerically lower than another group (5.4% versus 8.2%), but this difference was not statistically significant. Regarding types of MI, anterior wall MI was higher in non-addicted patients than addicts (36.4% versus 26.4%). Among patients with anterior wall MI, early mortality was significantly higher in non-addicted compared to addicted subjects (20.0% versus 7.9% P = 0.043). The main associated factors of in-hospital mortality due to acute MI in addicts were advanced age and family history of coronary artery disease and in non-addicts were advanced age and hypertension. Conclusion In current study total in-hospital mortality was not different between opium addicted and non-addicted groups but opium may reduce the occurrence of anterior wall MI and its related early mortality. PMID:24494156

Dehghani, Farnaz; Masoomi, Mohammad; Haghdoost, Ali Akbar

2013-01-01

101

Myocardial Infarction After Acute Carbon Monoxide Poisoning: Case Report  

Microsoft Academic Search

A 28-year-old man with acute myocardial infarction after carbon monoxide poisoning is reported. He had chest pain after the exposure to carbon monoxide. The electrocardiogram, serum enzymes, and technetium-99m pyrophosphate scintigrams showed anterior myocardial infarction. The coronary angiogram, which was performed one month after the onset, showed no visible atheroscler otic lesion. As to the cause of myocardial infarction, it

Shoji Ebisuno; Masao Yasuno; Yoshio Yamada; Yoshihide Nishino; Masatsugu Hori; Michitoshi Inoue; Takenobu Kamada

1986-01-01

102

MRI for the evaluation of regional myocardial perfusion in an experimental animal model.  

PubMed

Myocardial perfusion was assessed in nine pigs using ultrafast gradient-echo MRI (.5 T, 15-mT/m gradients) at different levels of myocardial blood flow (range, .005-1.84 ml/min/g), generated either by adenosine infusion or by a mechanical occluder, and measured independently using radiolabeled microspheres. Sixty-four consecutive, ECG-triggered, diastolic, short axis images of the left ventricle were obtained during intravenous bolus injections (n = 30) of .05 mmol/kg of gadopentetate dimeglumine. Relative changes in peak intensity, time to peak intensity, washin slope, correlation coefficient, and cross-correlation coefficient were computed from the time-intensity curves obtained from four regions of interest, namely septal, anterior, lateral, and inferior walls. The values from the inferior wall acted as reference for evaluating relative changes in the other three regions. The cross-correlation coefficient (P < .001, rho = .60) and the peak intensity (P < .001, r = .72) showed the best correlation with myocardial blood flow. The washin slope showed a weak positive trend (P < .05), but the low value of r (r = .28) indicated that the use of this parameter to predict flow was invalid; the correlation coefficient and time to peak intensity were not correlated (P = ns). In conclusion, this study shows that it is possible to evaluate relative myocardial perfusion after the first pass of a an intravenously injected bolus of gadopentetate dimeglumine, using dynamic MRI on a conventional medium field MRI system. The cross-correlation coefficient and the peak intensity resulted in more efficient parameters to evaluate relative inhomogeneity of regional myocardial perfusion. PMID:9400841

Lombardi, M; Jones, R A; Westby, J; Kvaerness, J; Torheim, G; Michelassi, C; L'Abbate, A; Rinck, P A

1997-01-01

103

Mapping myocardial fiber orientation using echocardiography-based shear wave imaging.  

PubMed

The assessment of disrupted myocardial fiber arrangement may help to understand and diagnose hypertrophic or ischemic cardiomyopathy. We hereby proposed and developed shear wave imaging (SWI), which is an echocardiography-based, noninvasive, real-time, and easy-to-use technique, to map myofiber orientation. Five in vitro porcine and three in vivo open-chest ovine hearts were studied. Known in physics, shear wave propagates faster along than across the fiber direction. SWI is a technique that can generate shear waves travelling in different directions with respect to each myocardial layer. SWI further analyzed the shear wave velocity across the entire left-ventricular (LV) myocardial thickness, ranging between 10 (diastole) and 25 mm (systole), with a resolution of 0.2 mm in the middle segment of the LV anterior wall region. The fiber angle at each myocardial layer was thus estimated by finding the maximum shear wave speed. In the in vitro porcine myocardium (n=5) , the SWI-estimated fiber angles gradually changed from +80° ± 7° (endocardium) to +30° ± 13° (midwall) and -40° ± 10° (epicardium) with 0° aligning with the circumference of the heart. This transmural fiber orientation was well correlated with histology findings. SWI further succeeded in mapping the transmural fiber orientation in three beating ovine hearts in vivo. At midsystole, the average fiber orientation exhibited 71° ± 13° (endocardium), 27° ± 8° (midwall), and -26° ± 30° (epicardium). We demonstrated the capability of SWI in mapping myocardial fiber orientation in vitro and in vivo. SWI may serve as a new tool for the noninvasive characterization of myocardial fiber structure. PMID:22020673

Lee, Wei-Ning; Pernot, Mathieu; Couade, Mathieu; Messas, Emmanuel; Bruneval, Patrick; Bel, Alain; Hagège, Albert A; Fink, Mathias; Tanter, Mickaël

2012-03-01

104

Anomalous left anterior descending artery to coronary sinus fistula with associated localized ischemia: A clinical dilemma  

PubMed Central

Patient: Female, 57 Final Diagnosis: Coronary sinus – venous fistula Symptoms: Dispnoea Medication: — Clinical Procedure: — Specialty: Cardiology Objective: Rare disease Background: Coronary arterial fistula, or arteriovenous malformation (AVM), is a connection between the coronary tree and a cardiac chamber or great vessel, having bypassed the myocardial capillary bed. Known complications from coronary artery fistulas may include “steal” from the adjacent myocardium, resulting in myocardial ischemia. Case Report: We report the case of a 57-year-old Hispanic woman with abnormal preoperative electrocardiogram (ECG) and symptoms of dyspnea on exertion, who underwent a stress echocardiography demonstrating inferior distribution hypokinesis at peak exercise. Coronary computed tomography angiography (CCTA) demonstrated a venous fistula connecting the coronary sinus (CS) with the distal portion of the left anterior descending artery (LAD), occupying the territory of a left posterior descending artery (L-PDA) and corresponding in distribution with the patient’s stress-induced wall motion abnormalities. Conclusions: Anomalous left anterior descending artery to coronary sinus fistula with associated ischemia is a rare clinical dilemma with limited experience of success with either surgical or medical options. PMID:24644528

Russo, Frank D.; Ahmadian, Homayoun R.; Slim, Ahmad M.

2014-01-01

105

Mathematical model of blunt injury to the vascular wall via formation of rouleaux and changes in local hemodynamic and rheological factors. Implications for the mechanism of traumatic myocardial infarction  

PubMed Central

Background Blood viscosity is fundamentally important in clinical practice yet the apparent viscosity at very low shear rates is not well understood. Various conditions such as blunt trauma may lead to the appearance of zones inside the vessel where shear stress equals zero. The aim of this research was to determine the blood viscosity and quantitative aspects of rouleau formation from erythrocytes at yield velocity (and therefore shear stress) equal to zero. Various fundamental differential equations and aspects of multiphase medium theory have been used. The equations were solved by a method of approximation. Experiments were conducted in an aerodynamic tube. Results The following were determined: (1) The dependence of the viscosity of a mixture on volume fraction during sedimentation of a group of particles (forming no aggregates), confirmed by published experimental data on the volume fractions of the second phase (f2) up to 0.6; (2) The dependence of the viscosity of the mixture on the volume fraction of erythrocytes during sedimentation of rouleaux when yield velocity is zero; (3) The increase in the viscosity of a mixture with an increasing erythrocyte concentration when yield velocity is zero; (4) The dependence of the quantity of rouleaux on shear stress (the higher the shear stress, the fewer the rouleaux) and on erythrocyte concentration (the more erythrocytes, the more rouleaux are formed). Conclusions This work represents one of few attempts to estimate extreme values of viscosity at low shear rate. It may further our understanding of the mechanism of blunt trauma to the vessel wall and therefore of conditions such as traumatic acute myocardial infarction. Such estimates are also clinically significant, since abnormal values of blood viscosity have been observed in many pathological conditions such as traumatic crush syndrome, cancer, acute myocardial infarction and peripheral vascular disease. PMID:15799779

Ismailov, Rovshan M

2005-01-01

106

Accuracy of localization of acute myocardial infarction by 12 lead electrocardiography  

SciTech Connect

Until recently, ECG accuracy in localizing acute myocardial infarction (AMI) could be assessed only by comparing the ECGs with autopsy findings. This approach, however, preselected patients, including only those who died. It is possible that this postmortem group of patients would be different from the whole population of patients with AMI. Myocardial imaging with /sup 99/mTc-pyrophosphate offers the advantage of directly localizing the region of injured myocardium in the acute phase of AMI. In 34 patients with confirmed AMI and focal uptake of /sup 99/mTc-pyrophosphate, serial ECGs were obtained and interpreted by two independent observers. The sensitivity and specificity of serial ECGs in determining the location of AMI in the five left ventricular (LV) wall segments were determined: (1) in the anterior wall sensitivity was 86.7% and specificity was 89.5%; (2) in the lateral wall sensitivity was 73.7% and specificity was 80.0%; (3) in the high lateral wall sensitivity was 80.0% and specificity was 87.5%; (4) in the inferior wall sensitivity was 87.5% and specificity was 100%; (5) in the true posterior wall sensitivity was 83.3% and specificity was 86.4%. Overall, in the 170 LV wall segments (five per patient) examined, scans localized with a sensitivity of 81.9% and a specificity of 88.8%. After four patients with LBBB were excluded, sensitivity increased to 87.1%. Overall, localization of AMI by serial ECG was accurate in 85.9% of the 34 patients included in the study.

Yasuda, T.; Ribeiro, L.G.; Holman, B.L.; Alpert, J.S.; Maroko, P.R.

1982-04-01

107

Value and limitations of segmental analysis of stress thallium myocardial imaging for localization of coronary artery disease  

SciTech Connect

This study was done to determine the value of thallium-201 myocardial scintigraphic imaging (MSI) for identifying disease in the individual coronary arteries. Segmental analysis of rest and stress MSI was performed in 133 patients with ateriographically proved coronary artery disease (CAD). Certain scintigraphic segments were highly specific (97 to 100%) for the three major coronary arteries: anterior wall and septum for the left anterior descending (LAD) coronary artery; the inferior wall for the right coronary artery (RCA); and the proximal lateral wall for the circumflex (LCX) artery. Perfusion defects located in the anterolateral wall in the anterior view were highly specific for proximal disease in the LAD involving the major diagonal branches, but this was not true for septal defects. The apical segments were not specific for any of the three major vessels. Although MSI was abnormal in 89% of these patients with CAD, it was less sensitive for identifying individual vessel disease: 63% for LAD, 50% for RCA, and 21% for LCX disease (narrowings > = 50%). Sensitivity increased with the severity of stenosis, but even for 100% occlusions was only 87% for LAD, 58% for RCA and 38% for LCX. Sensitivity diminished as the number of vessels involved increased: with single-vessel disease, 80% of LAD, 54% of RAC and 33% of LCX lesions were detected, but in patients with triple-vessel disease, only 50% of LAD, 50% of RCA and 16% of LCX lesions were identified. Thus, although segmented analysis of MSI can identify disease in the individual coronary arteries with high specificity, only moderate sensitivity is achieved, reflecting the tendency of MSI to identify only the most severely ischemic area among several that may be present in a heart. Perfusion scintigrams display relative distributions rather than absolute values for myocardial blood flow.

Rigo, P.; Bailey, I.K.; Griffith, L.S.C.; Pitt, B.; Borow, R.D.; Wagner, H.N.; Becker, L.C.

1980-05-01

108

Scintigraphic assessment of sympathetic innervation after transmural versus nontransmural myocardial infarction  

SciTech Connect

To evaluate the feasibility of detecting denervated myocardium in the infarcted canine heart, the distribution of sympathetic nerve endings using I-123 metaiodobenzylguanidine (MIBG) was compared with the distribution of perfusion using thallium-201, with the aid of color-coded computer functional map in 16 dogs. Twelve dogs underwent myocardial infarction by injection of vinyl latex into the left anterior descending coronary artery (transmural myocardial infarction, n = 6), or ligation of the left anterior descending coronary artery (nontransmural myocardial infarction, n = 6). Four dogs served as sham-operated controls. Image patterns were compared with tissue norepinephrine content and with histofluorescence microscopic findings in biopsy specimens. Hearts with transmural infarction showed zones of absent MIBG and thallium, indicating scar. Adjacent and distal regions showed reduced MIBG but normal thallium uptake, indicating viable but denervated myocardium. Denervation distal to infarction was confirmed by reduced norepinephrine content and absence of nerve fluorescence. Nontransmural myocardial infarction showed zones of wall thinning with decreased thallium uptake and a greater reduction or absence of MIBG localized to the region of the infarct, with minimal extension of denervation beyond the infarct. Norepinephrine content was significantly reduced in the infarct zone, and nerve fluorescence was absent. These findings suggest that (1) MIBG imaging can detect viable and perfused but denervated myocardium after infarction; and (2) as opposed to the distal denervation produced by transmural infarction, nontransmural infarction may lead to regional ischemic damage of sympathetic nerves, but may spare subepicardial nerve trunks that course through the region of infarction to provide a source of innervation to distal areas of myocardium.

Dae, M.W.; Herre, J.M.; O'Connell, J.W.; Botvinick, E.H.; Newman, D.; Munoz, L. (University of California, San Francisco (USA))

1991-05-01

109

Prediction of single versus multivessel disease following myocardial infarction using 201-thallium scintigraphy and electrocardiographic stress testing  

SciTech Connect

Fifty patients were evaluated who suffered a single myocardial infarction with graded electrocardiographic stress testing, 201-thallium myocardial perfusion imaging and coronary angiography to assess the role of noninvasive indices as predictors of single versus multivessel coronary artery disease. Multivessel involvement was defined angiographically as the presence of two or more major coronary arteries with at least a 70% intraluminal diameter narrowing. Multivessel disease was defined scintigraphically as the presence of stress and/or redistribution perfusion defects in the distribution of more than one coronary artery. The results of stress electrocardiography were not useful in differentiating patients with single (9/16 positive) versus multivessel (22/34 positive) disease. The degree of exercise-induced ST-segment depression was also not helpful. Stress 201-thallium imaging did offer limited additional information with correct predictions of multivessel disease in 21 of 26 patients. Predictions of single-vessel disease were accurate in 11 of 24 patients. Eleven of these 13 incorrect predictions of single-vessel disease were due to the relative insensitivity of the thallium stress image to perceive defect in the anterior wall when the left anterior descending artery had significant obstruction at catheterization. Further refinements of stress perfusion imaging are needed before this method can be used to reliably separate patients with single and multivessel disease after myocardial infarction.

Weiss, R.J.; Morise, A.P.; Raabe, D.S. Jr.; Sbarbaro, J.A.

1983-11-01

110

[Type IV dual left anterior descending coronary artery - a rare congenital coronary artery anomaly. A case report].  

PubMed

An extremely rare case of type IV dual left anterior descending coronary artery coexisting with myocardial bridging in a 50-year old Caucasian man with acute coronary syndrome is presented. Emergency cardiac catheterisation revealed no coronary atherosclerotic lesions. The potential causal relationship between the type IV dual left anterior descending coronary artery and myocardial ischaemia was discussed. We also summarised the current knowledge on the epidemiology and clinical significance of dual left anterior descending coronary artery in the adult population. PMID:20411463

Paradowski, Andrzej; Rostoff, Pawe?; Gajos, Grzegorz; Gackowski, Andrzej; Klimeczek, Piotr; Krupi?ski, Maciej; Pasowicz, Mieczys?aw; Piwowarska, Wies?awa

2010-03-01

111

The effects of thoracic epidural anesthesia on functional recovery from myocardial stunning in propofol-anesthetized dogs.  

PubMed

The purpose of this investigation was to examine the effects of thoracic epidural anesthesia (TEA) on myocardial stunning during propofol anesthesia. Six dogs were chronically instrumented for measurement of left atrial, aortic, and left ventricular pressure, maximal rate of increase of left ventricular pressure, and myocardial wall-thickening fraction (WTF). Myocardial blood flow was determined with colored microspheres. Experiments were performed on separate days with 1) 10 min of left anterior descending artery (LAD) ischemia during propofol anesthesia without TEA, and 2) 10 min of LAD ischemia during propofol anesthesia with TEA. WTF was measured as baseline (BL) prior to propofol anesthesia and at predetermined time points until complete recovery from stunning. Propofol anesthesia caused a significant decrease of WTF in the LAD-perfused myocardium (LAD-WTF) compared to BL in awake animals. LAD ischemia led to a further significant decrease of LAD-WTF. There were no significant differences in LAD-WTF between the two experimental conditions at any of the time points measured. TEA did not change subendocardial blood flow in nonischemic myocardium. During ischemia neither the subendocardial/subepicardial nor the occluded/normal zone blood flow ratio were affected by TEA. After myocardial ischemia during propofol anesthesia TEA does not affect functional recovery of stunned myocardium in dogs. PMID:9085946

Rolf, N; Meissner, A; Van Aken, H; Weber, T P; Hammel, D; Möllhoff, T

1997-04-01

112

Thoracic epidural anesthesia improves functional recovery from myocardial stunning in conscious dogs.  

PubMed

The effects of thoracic epidural anesthesia (TEA) on the contractile performance of ischemic and postischemic myocardium have not been well investigated. The purpose of this investigation was to examine the effects of TEA on severity and duration of myocardial stunning in an experimental model for sublethal acute myocardial ischemia. Seven dogs were chronically instrumented for measurement of heart rate (HR), left atrial (LAP), aortic and left ventricular pressure (LVP), LV dP/dtmax' and myocardial wall-thickening fraction (WTF). An occluder around the left anterior descending artery (LAD) allowed induction of reversible LAD ischemia. TEA was performed with lidocaine 4 mg/kg through a chronically implanted epidural catheter at the second thoracic level. Regional myocardial blood flow was determined with colored microspheres. Two experiments were performed in a cross-over design on separate days: Experiment 1, induction of 10 min of LAD ischemia without TEA; and Experiment 2, induction of 10 min of LAD ischemia with TEA. WTF was measured at baseline (BL) and predetermined time points until complete recovery from ischemic dysfunction occurred. LAD ischemia caused a significant decrease of LAD-WTF with (-28% +/- 5.1% versus BL) and without TEA (-15.5% +/- 5.3% versus BL). After 3 h of reperfusion, WTF as percent of BL values was significantly higher with TEA (P < 0.001). BL values of WTF were reached after 24 h with TEA and after more than 48 h without TEA (P < 0.05). There were no significant differences for mean arterial pressure (MAP), heart rate (HR), LVP, LAP, and LVdP/dtmax between the groups during ischemia and reperfusion. In nonischemic myocardium TEA caused an increase of subendocardial blood flow. During ischemia neither the subendocardial/subepicardial nor the occluded/ normal zone blood flow was affected by TEA. TEA attenuates myocardial stunning in conscious dogs. This finding is consistent with data regarding a reduction of infarct size due to TEA. PMID:8895266

Rolf, N; Van de Velde, M; Wouters, P F; Möllhoff, T; Weber, T P; Van Aken, H K

1996-11-01

113

Myocardial Angiogenesis  

Microsoft Academic Search

Improvements in pharmacological therapy and revascularization procedures have greatly increased the life expectancy of patients\\u000a with coronary artery disease (CAD) in the last few decades. As a result of these improvements in cardiovascular care and the\\u000a aging of the population, anincreasing number of patients have incomplete revascularization or recurrent myocardial ischemia\\u000a and are suboptimal candidates for surgical (coronary artery bypass

Kwang Soo Cha; Robert S. Schwartz; Timothy D. Henry

114

Anterior chest wall inflammation by whole-body magnetic resonance imaging in patients with spondyloarthritis: lack of association between clinical and imaging findings in a cross-sectional study  

PubMed Central

Introduction Inflammatory involvement of the anterior chest wall (ACW) affects the quality of life of patients with spondyloarthritis (SpA), although involvement of the ACW is often neglected on clinical and imaging evaluation. Whole-body (WB) MRI is an imaging method used to assess the ACW in addition to the sacroiliac joints and spine without inconvenience for patients. Our goals in this study were to describe the distribution of ACW inflammation by WB MRI in both early and established SpA and associations between clinical and imaging findings indicative of inflammation. Methods The ACWs of 122 consecutive SpA patients (95 with ankylosing spondylitis (AS) and 27 with nonradiographic SpA (nrSpA)) and 75 healthy controls were scanned by sagittal and coronal WB MRI. The MRI scans were scored independently in random order by seven readers blinded to patient identifiers. Active and structural inflammatory lesions of the ACW were recorded on a web-based data entry form. ACW pain by patient self-report, ACW tenderness on physical examination according to the Maastricht Ankylosing Spondylitis Enthesitis Score (MASES) and lesions detected by MRI were analyzed descriptively. ? statistics served to assess the agreement between clinical and imaging findings. Results ACW pain or tenderness was present in 26% of patients, with little difference between AS and nrSpA patients. Bone marrow edema (BME), erosion and fat infiltration were recorded in 44.3%, 34.4% and 27.0% of SpA patients and in 9.3%, 12.0% and 5.3% of controls, respectively. Lesions found by MRI occurred more frequently in AS patients (BME, erosion and fat infiltration in 49.5%, 36.8% and 33.7%, respectively) than in nrSpA patients (25.9%, 25.9% and 3.7%, respectively). The joint most frequently affected by lesions found on MRI scans was the manubriosternal joint. The ? values between clinical assessments and MRI inflammation ranged from -0.10 to only 0.33 for both AS and nrSpA patients. Conclusions Among SpA patients, 26% had clinical involvement of the ACW. WB MRI signs of ACW inflammation were found in a substantial proportion of patients with AS (49.5%) and nrSpA (25.9%). There was no association between clinical assessments of ACW, including the MASES, and MRI features. PMID:22226453

2012-01-01

115

Transient integral boundary layer method to calculate the translesional pressure drop and the fractional flow reserve in myocardial bridges  

PubMed Central

Background The pressure drop – flow relations in myocardial bridges and the assessment of vascular heart disease via fractional flow reserve (FFR) have motivated many researchers the last decades. The aim of this study is to simulate several clinical conditions present in myocardial bridges to determine the flow reserve and consequently the clinical relevance of the disease. From a fluid mechanical point of view the pathophysiological situation in myocardial bridges involves fluid flow in a time dependent flow geometry, caused by contracting cardiac muscles overlying an intramural segment of the coronary artery. These flows mostly involve flow separation and secondary motions, which are difficult to calculate and analyse. Methods Because a three dimensional simulation of the haemodynamic conditions in myocardial bridges in a network of coronary arteries is time-consuming, we present a boundary layer model for the calculation of the pressure drop and flow separation. The approach is based on the assumption that the flow can be sufficiently well described by the interaction of an inviscid core and a viscous boundary layer. Under the assumption that the idealised flow through a constriction is given by near-equilibrium velocity profiles of the Falkner-Skan-Cooke (FSC) family, the evolution of the boundary layer is obtained by the simultaneous solution of the Falkner-Skan equation and the transient von-Kármán integral momentum equation. Results The model was used to investigate the relative importance of several physical parameters present in myocardial bridges. Results have been obtained for steady and unsteady flow through vessels with 0 – 85% diameter stenosis. We compare two clinical relevant cases of a myocardial bridge in the middle segment of the left anterior descending coronary artery (LAD). The pressure derived FFR of fixed and dynamic lesions has shown that the flow is less affected in the dynamic case, because the distal pressure partially recovers during re-opening of the vessel in diastole. We have further calculated the wall shear stress (WSS) distributions in addition to the location and length of the flow reversal zones in dependence on the severity of the disease. Conclusion The described boundary layer method can be used to simulate frictional forces and wall shear stresses in the entrance region of vessels. Earlier models are supplemented by the viscous effects in a quasi three-dimensional vessel geometry with a prescribed wall motion. The results indicate that the translesional pressure drop and the mean FFR compares favourably to clinical findings in the literature. We have further shown that the mean FFR under the assumption of Hagen-Poiseuille flow is overestimated in developing flow conditions. PMID:16790065

Bernhard, Stefan; Mohlenkamp, Stefan; Tilgner, Andreas

2006-01-01

116

Autologous porcine heart cell transplantation improved heart function after a myocardial infarction  

Microsoft Academic Search

Objective: Fetal cardiomyocyte transplantation improved heart function after cardiac injury. However, cellular allografts were rejected despite cyclosporine (INN: ciclosporin) therapy. We therefore evaluated autologous heart cell transplantation in an adult swine model of a myocardial infarction. Methods: In 16 adult swine a myocardial infarction was created by occlusion of the distal left anterior descending coronary artery by an intraluminal coil.

Ren-Ke Li; Richard D. Weisel; Donald A. G. Mickle; Zhi-Qiang Jia; Eung-Joong Kim; Tetsuro Sakai; Shinji Tomita; Leonard Schwartz; Mark Iwanochko; Mansoor Husain; Robert J. Cusimano; Robert J. Burns; Terrence M. Yau

2000-01-01

117

Fourier Phase Analysis Can Be Used to Objectively Analyze Real-Time Myocardial Contrast Echocardiograms  

Microsoft Academic Search

Background: Real-time myocardial contrast echocardiography (MCE) is increasingly used to assess myocardial perfusion. However, objective methods for evaluating MCE are not yet widely available. We sought to validate the ability of Fourier analysis applied to MCE to assess serial changes in microvascular perfusion during coronary occlusion and reperfusion. Methods: Six pigs underwent 45 min of left anterior descending coronary artery

Alexander Hansen; Raffi Bekeredjian; Grigorious Korosoglou; David Wolf; Arthur Filusch; Helmut F. Kuecherer

2004-01-01

118

Myocardial infarction in young people with normal coronary arteries  

PubMed Central

Myocardial infarction occurring in young people with angiographically normal coronary arteries is well described but the pathophysiology of this condition remains unknown. Coronary artery spasm in association with thrombus formation and minimal atheromatous disease or spontaneous coronary artery dissection are possible causes. Two young men presented with severe chest pain after acute alcohol intoxication and each sustained an extensive anterior myocardial infarction. Investigations including intravascular ultrasound showed no evidence of atherosclerotic coronary artery disease. Coronary artery spasm associated with acute alcohol intoxication as well as a prothrombotic state and endothelial damage related to cigarette smoking may be mechanisms leading to acute myocardial infarction in these cases. Acute myocardial infarction occurs in young persons with normal coronary arteries and the diagnosis should be considered in young patients presenting with severe chest pain, particularly those abusing cocaine or alcohol, so that reperfusion therapy can be initiated promptly.?? Keywords: myocardial infarction;  coronary vasospasm;  alcohol;  intravascular ultrasound PMID:9538315

Williams, M; Restieaux, N; Low, C

1998-01-01

119

Microvascular Resistance Predicts Myocardial Salvage and Infarct Characteristics in ST-Elevation Myocardial Infarction  

PubMed Central

Background The pathophysiology of myocardial injury and repair in patients with ST?elevation myocardial infarction is incompletely understood. We investigated the relationships among culprit artery microvascular resistance, myocardial salvage, and ventricular function. Methods and Results The index of microvascular resistance (IMR) was measured by means of a pressure? and temperature?sensitive coronary guidewire in 108 patients with ST?elevation myocardial infarction (83% male) at the end of primary percutaneous coronary intervention. Paired cardiac MRI (cardiac magnetic resonance) scans were performed early (2 days; n=108) and late (3 months; n=96) after myocardial infarction. T2?weighted? and late gadolinium–enhanced cardiac magnetic resonance delineated the ischemic area at risk and infarct size, respectively. Myocardial salvage was calculated by subtracting infarct size from area at risk. Univariable and multivariable models were constructed to determine the impact of IMR on cardiac magnetic resonance–derived surrogate outcomes. The median (interquartile range) IMR was 28 (17–42) mm Hg/s. The median (interquartile range) area at risk was 32% (24%–41%) of left ventricular mass, and the myocardial salvage index was 21% (11%–43%). IMR was a significant multivariable predictor of early myocardial salvage, with a multiplicative effect of 0.87 (95% confidence interval 0.82 to 0.92) per 20% increase in IMR; P<0.001. In patients with anterior myocardial infarction, IMR was a multivariable predictor of early and late myocardial salvage, with multiplicative effects of 0.82 (95% confidence interval 0.75 to 0.90; P<0.001) and 0.92 (95% confidence interval 0.88 to 0.96; P<0.001), respectively. IMR also predicted the presence and extent of microvascular obstruction and myocardial hemorrhage. Conclusion Microvascular resistance measured during primary percutaneous coronary intervention significantly predicts myocardial salvage, infarct characteristics, and left ventricular ejection fraction in patients with ST?elevation myocardial infarction. (J Am Heart Assoc. 2012;1:e002246 doi: 10.1161/JAHA.112.002246) PMID:23130166

Payne, Alexander R.; Berry, Colin; Doolin, Orla; McEntegart, Margaret; Petrie, Mark C.; Lindsay, M. Mitchell; Hood, Stuart; Carrick, David; Tzemos, Niko; Weale, Peter; McComb, Christie; Foster, John; Ford, Ian; Oldroyd, Keith G.

2012-01-01

120

Feasibility of voxel-based statistical analysis method for myocardial PET  

NASA Astrophysics Data System (ADS)

Although statistical parametric mapping (SPM) analysis is widely used in neuroimaging studies, to our best knowledge, there was no application to myocardial PET data analysis. In this study, we developed the voxel based statistical analysis method for myocardial PET which provides statistical comparison results between groups in image space. PET Emission data of normal and myocardial infarction rats were acquired For the SPM analysis, a rat heart template was created. In addition, individual PET data was spatially normalized and smoothed. Two sample t-tests were performed to identify the myocardial infarct region. This developed SPM method was compared with conventional ROI methods. Myocardial glucose metabolism was decreased in the lateral wall of the left ventricle. In the result of ROI analysis, the mean value of the lateral wall was 29% decreased. The newly developed SPM method for myocardial PET could provide quantitative information in myocardial PET study.

Ram Yu, A.; Kim, Jin Su; Paik, Chang H.; Kim, Kyeong Min; Moo Lim, Sang

2014-09-01

121

Comparison of two-dimensional echocardiography with gated radionuclide ventriculography in the evaluation of global and regional left ventricular function in acute myocardial infarction  

SciTech Connect

Two-dimensional echocardiography and gated radionuclide ventriculography were performed in 93 patients (66 men, 27 women; mean age 61 years) with 95 episodes of acute myocardial infarction within 48 hours and at 10 days after infarction. Abnormal motion of an inferior or posterior wall segment was seen in 91% of inferoposterior infarctions by echocardiography versus 61% seen by radionuclide ventriculography. Ejection fractions determined by echocardiography and radionuclide ventriculography correlated well (r . 0.82) and did not change from the first 48 hours to 10 days after infarction (0.48 +/- 0.14). Similarly, wall motion score showed minimal change from the first 48 hours to 10 days. In-hospital mortality was 37 and 42% in patients with an ejection fraction of 0.35 or less by echocardiography and radionuclide ventriculography, respectively. No mortality was seen in patients with an ejection fraction above 0.40 by either test. The echocardiographic wall motion score was also predictive of mortality (40 versus 2%; score less than or equal to 0.50 versus greater than 0.50). The 1 year mortality rate in the 81 short-term survivors was 17%. Mortality was lowest in patients with an ejection fraction above 0.49 or wall motion score above (0.79 (2 to 5%) and worse in those with an ejection fraction below 0.36 or wall motion score below 0.51 (36 to 63%) by either technique. Thus in acute myocardial infarction, echocardiography and radionuclide ventriculography provide a comparable assessment of left ventricular function and wall motion in anterior infarction. Echocardiography appears more sensitive in detecting inferoposterior wall motion abnormalities. Both techniques are capable of identifying subgroups of patients with a high risk of death during the acute event and with an equally high mortality rate over a 1 year follow-up period.

Van Reet, R.E.; Quinones, M.A.; Poliner, L.R.; Nelson, J.G.; Waggoner, A.D.; Kanon, D.; Lubetkin, S.J.; Pratt, C.M.; Winters, W.L. Jr.

1984-02-01

122

Anterior bony ankle impingement  

Microsoft Academic Search

Anterior bony ankle impingement results from osteophyte formation on the anterior edge of the distal tibia and\\/or neck of the talus, secondary to direct trauma during extreme or repetitive ankle dorsiflexion. It is common in ballet dancers, gymnasts, soccer players, football players, runners, and high jumpers. Typically, patients will complain of painful limitation of dorsiflexion, catching, and swelling in the

Brian G. Donley; Manuel Leyes

2001-01-01

123

Myocardial imaging. Coxsackie myocarditis  

SciTech Connect

A 3-week-old male neonate with heart failure associated with Coxsackie virus infection was imaged with Tc-99m PYP and TI-201. The abnormal imaging pattern suggested myocardial infarction. Autopsy findings indicated that the cause was myocardial necrosis secondary to an acute inflammatory process. Causes of abnormal myocardial uptake of Tc-99m PYP in pediatrics include infarction, myocarditis, cardiomyopathy, bacterial endocarditis, and trauma. Myocardial imaging cannot provide a specific cause diagnosis. Causes of myocardial infarction in pediatrics are listed in Table 1.

Wells, R.G.; Ruskin, J.A.; Sty, J.R.

1986-09-01

124

New approach to quantitation of exercise thallium-201 scintigraphy before and after an intervention: application to define the impact of coronary angioplasty on regional myocardial perfusion  

SciTech Connect

We have developed a new computer method designed to quantitate regional myocardial thallium-201 (TI-201) initial distribution, redistribution, and clearance rate. In addition, this computer method permits the generation of functional images to compare two thallium images in the same projection to one another. These functional images can be used to demonstrate the extent of redistribution and the extent of change in regional perfusion before and after an intervention. To validate and apply this new computer technique, exercise TI-201 myocardial images obtained before and 1 week after percutaneous transluminal coronary angioplasty (PTCA) were analyzed in 20 patients with isolated left anterior descending coronary artery disease. Significant improvement in initial TI-201 activity, expressed as a percentage of maximal myocardial activity, was present in the anterior (71.9 +/- 12.0 to 84.1 +/- 11.5%, p less than 0.001) and septal (66.7 +/- 15.4 to 75.2 +/- 11.0%, p less than 0.05) regions of the left ventricle 1 week after PTCA. This increase in relative anterior wall TI-201 uptake was associated with a significant reduction in the amount of TI-201 redistribution between initial and delayed postexercise images (14.7 +/- 14.6 to 3.0 +/- 13.2%, p less than 0.05) as well as an increase in TI-201 clearance rate (t 1/2 from 8.8 +/- 4.4 to 4.3 +/- 2.5 hours, p less than 0.001). Quantitative analysis of TI-201 scans demonstrated improvement in 14 of 20 patients following PTCA. Computer-derived functional difference images depicted diminution in the extent of ischemia as manifested by redistribution of TI-201.

Lim, Y.L.; Okada, R.D.; Chesler, D.A.; Block, P.C.; Boucher, C.A.; Pohost, G.M.

1984-10-01

125

Effects of time required for reperfusion (thrombolysis or angioplasty, or both) and location of acute myocardial infarction on left ventricular functional reserve capacity several months later  

SciTech Connect

The purpose of this study was to determine whether reperfusion of acute myocardial infarction (AMI) by recombinant tissue-type plasminogen activator (rt-PA) or percutaneous transluminal coronary angioplasty, or both, would improve left ventricular (LV) function when it is measured several months later at rest or maximal bicycle exercise, or both. Radionuclide angiography was performed in 44 patients 5 months (range 6 weeks to 9 months) after AMI to assess function, and tomographic myocardial thallium-201 imaging was performed at maximal exercise and delayed rest to determine whether there was any evidence of myocardial ischemia. As expected, no patient had chest pain or redistribution of a thallium defect during the exercise test, because patients had undergone angioplasty (n = 28) or coronary bypass graft surgery (n = 5) where clinically indicated for revascularization. The LV ejection fraction was plotted as a function of the time elapsed between the onset of chest pain and the time when coronary angiography confirmed patency of the infarct-related artery (achieved in 91% of 44 patients by rt-PA (n = 31) or percutaneous transluminal coronary angioplasty (n = 9) ). Functional responses differed markedly between patients with anterior (n = 20) versus inferior (n = 24) wall AMI. LV ejection fraction during exercise correlated with time to reperfusion in patients with an anterior wall AMI (r = -0.58; standard error of the estimate = 11.9%; p less than 0.02) but not in patients with an inferior AMI (r = 0.10; standard error of the estimate = 13.1%); difference not significant.

Little, T.; Crenshaw, M.; Liberman, H.A.; Battey, L.L.; Warner, R.; Churchwell, A.L.; Eisner, R.L.; Morris, D.C.; Patterson, R.E. (Emory Univ., Atlanta, GA (USA))

1991-04-15

126

[Myocardial infarction and thromboembolism during pregnancy].  

PubMed

Acute myocardial infarction is a very rare event during pregnancy and bears the problem of misdiagnosis. However, about 150 cases have been published worldwide with a preponderance of anterior wall infarcts. With more women delaying childbearing until an older age and increasing prevalence of smoking in young women, it can be expected that all forms of coronary artery disease--including acute myocardial infarction--will be seen more often in the future. Among the causes of coronary artery occlusion in pregnancy are (1) rupture of very small coronary artery plaques triggered by different events, e.g., hypertension; (2) plain coronary artery disease; (3) dissection of coronary arteries; (4) coronary artery spasms with/without arterial thrombosis. Prompt diagnosis and immediate therapy are necessary to lower the high mortality of mother and fetus. The gold standard in the therapy of acute myocardial infarction during pregnancy is immediate coronary angiography and percutaneous transluminal coronary angioplasty (PTCA) with or without stent implantation. Application of thrombolytics (recombinant tissue plasminogen activator [rt-PA], r-PA, streptokinase [SK], urokinase [UK]) has been reported in single patients but should be limited to cases where acute PTCA is not available and where the infarct occurs before the 14th week of pregnancy because of possible embryopathy. If the patient is in the last 10 weeks of pregnancy, anticipation of delivery should be part of the medical planning. Consultation with an obstetrician must be obtained as soon as the patient enters the hospital. Besides bleeding complications, venous thrombosis with pulmonary embolism is among the most common causes of death during pregnancy. Pregnancy-related changes in physiology - increase in the resistance to flow from the lower extremities to the heart - and congenital coagulation abnormalities are most important to be recognized. This leads to the fact that superficial and deep venous thromboses occur more often in pregnancy than in the nonpregnant state. Among the coagulation abnormalities found in pregnancy are hypercoagulability (increased levels of fibrinogen, factor VII, factor VIII, factor X), decreased fibrinolytic activity due to an increased level of plasminogen activator inhibitor, increased adhesion and aggregation of platelets, decreased level of protein C and of the APC (activated protein C) ratio. Individual risks factors justifying diagnostic screening include contraception, smoking, immobilization, infection, adiposity, placental insufficiency, and a family history of thrombosis. It is even more important to establish/rule out the diagnosis of thrombosis in pregnancy than in the nonpregnant state, because the use of anticoagulants carries certain risks during pregnancy. Doppler vein studies should be used for diagnosis. If necessary, venography may be used with shielding of the maternal abdomen. Therapy consists of subcutaneous application of heparin, compression, and early mobilization. Alternatively, especially for long-term management, treatment with low molecular weight heparins is feasible. Thrombolytic treatment is contraindicated in most cases due to the high risk of bleeding complications. However, the application of thrombolytics can be contemplated in single cases after careful consideration of the pros and cons. Most cases of pulmonary embolism should also be handled conservatively with heparin. Only in massive pulmonary embolism with severe hemodynamic compromise, thrombolytic treatment is indicated. To guide future therapy in the patients, it is necessary to establish the lifetime risk of recurrent events by determining: APC resistance, prothrombin mutation 20210 A, homocysteine, AT III, protein C and S, antiphospholipid antibodies, and anticardiolipin antibodies. PMID:12756475

Härtel, Dirk; Sorges, Eckhard; Carlsson, Jörg; Römer, Volker; Tebbe, Ulrich

2003-05-01

127

Effects of magnesium supplementation in a porcine model of myocardial ischemia and reperfusion.  

PubMed

We tested the hypothesis that acute, intravenous (i.v.) magnesium (Mg2+) supplementation would protect against myocardial stunning in an in situ swine model of regional ischemia and reperfusion and that a concomitant inhibitory effect on platelet aggregation would be elicited. An open-chest model was used, with transient occlusion of the left anterior descending coronary artery (LAD) for 8 min. Regional contractile function was assessed by measuring wall thickening fraction with epicardial Doppler crystals. One control group (n = 6) and two treatment groups were studied: group I (n = 6) received 750 mg MgSO4 before occlusion; group II (n = 6) received 1 g MgSO4 after the occlusion. Both protocols produced significant hypermagnesemia. In group I, platelet aggregation was measured before and after Mg2+ treatment using platelet-rich plasma (PRP) and various agonists (ADP 5 and 10 mM and collagen 1 mg/ml). As compared with controls, both treatment groups experienced significantly less postischemic dysfunction, with systolic function returning more quickly to baseline. Furthermore, platelet aggregation was significantly decreased immediately after Mg2+ infusion. Inhibition of platelet aggregation induced by Mg2+ treatment occurs concomitantly with significant amelioration of postischemic myocardial dysfunction. PMID:7528843

Atar, D; Serebruany, V; Poulton, J; Godard, J; Schneider, A; Herzog, W R

1994-10-01

128

Anterior glenohumeral joint dislocations.  

PubMed

The glenohumeral joint is the most mobile articulation in the body and the most commonly dislocated diarthroidal joint. Anterior dislocation is by far the most common direction and can lead to instability of the glenohumeral joint, which ranges from subtle increased laxity to recurrent dislocation. Overtime, understanding of anterior shoulder dislocations and the resulting instability has improved. Likewise, significant advances in arthroscopic equipment have allowed use of the arthroscope to address anatomically the various lesions that cause instability. This article reviews the anatomy, pathophysiology, clinical evaluation, and treatment of anterior shoulder instability. PMID:18803980

Dodson, Christopher C; Cordasco, Frank A

2008-10-01

129

Non-ST-elevation myocardial infarction after a wasp sting  

PubMed Central

We report a case of a 56-year-old woman with loss of conscious transferred to the cardiology unit where non-ST-elevation myocardial infarction was diagnosed. The patient reported a wasp sting a few minutes before the accident. The cardiac troponin level was high and confirmed damage of the heart muscle. Finally, echocardiography and myocardial perfusion scintigraphy revealed an ejection fraction of 50% with hypokinesia of posterior walls. Cardiac consequences of the insect venom sting are discussed in this article.

Pezold, Marcin; Bozek, Andrzej

2014-01-01

130

Effect of Wenxin Granule on Ventricular Remodeling and Myocardial Apoptosis in Rats with Myocardial Infarction  

PubMed Central

Aim. To determine the effect of a Chinese herbal compound named Wenxin Granule on ventricular remodeling and myocardial apoptosis in rats with myocardial infarction (MI). Methods. Male Sprague-Dawley (SD) rats were randomly divided into four groups: the control group, the model group, the metoprolol group, and the Wenxin Granule group (WXKL group) with sample size (n) of 7 rats in each group. An MI model was established in all rats by occlusion of the left anterior descending coronary artery (the control group was without occlusion). Wenxin Granule (1.35?g/kg/day), metoprolol (12?mg/kg/day), and distilled water (5?mL/kg/day for the control and model groups) were administered orally for 4 weeks. Ultrasonic echocardiography was used to examine cardiac structural and functional parameters. Myocardial histopathological changes were observed using haematoxylin and eosin (H&E) dyeing. Myocardial apoptosis was detected by terminal deoxynucleotidyl transferase mediated dUTP nick end labeling (TUNEL) staining. Serum angiotensin II (Ang II) concentration was measured using the enzyme-linked immunosorbent assay (ELISA). Results. It was found that Wenxin Granule could partially reverse ventricular remodeling, improve heart function, alleviate the histopathological damage, inhibit myocardial apoptosis, and reduce Ang II concentration in rats with MI. Conclusions. The results of the current study suggest that Wenxin Granule may be a potential alternative and complementary medicine for the treatment of MI. PMID:23997803

Wu, Aiming; Zhai, Jianying; Zhang, Dongmei; Lou, Lixia; Zhu, Haiyan; Gao, Yonghong; Chai, Limin; Xing, Yanwei; Lv, Xiying; Zhu, Lingqun; Zhao, Mingjing; Wang, Shuoren

2013-01-01

131

Quantitative two-dimensional echocardiographic assessment of regional wall motion during transient ischemia and reperfusion in the rat.  

PubMed

Nonlethal myocardial ischemia produces profound and long-lasting effects on regional ventricular function and metabolism (myocardial stunning) and protects against myocardial infarction from subsequent prolonged ischemia (ischemic preconditioning). Two-dimensional echocardiography (2DE) is an essential tool for quantitative analysis of regional and global left ventricular (LV) function during myocardial ischemia and reperfusion and the study of these phenomena. However, the inability to perform 2DE in the open-chest rat heart has seriously limited the use of this model. To investigate the effect of transient coronary occlusion on segmental wall motion and LV geometry, we employed a 20 MHz intravascular ultrasound catheter placed on the epicardial surface of the rat heart (n = 15) to yield 2DE images suitable for quantitative analysis. Three 2-minute left coronary occlusions were made, separated by 5 minutes of reperfusion, with imaging during occlusion and at 5 and 60 minutes of reperfusion. Ischemic and nonischemic wall thicknesses, LV cross-sectional area, estimated LV volume, and the fractional changes of these parameters were measured. In eight animals these values were also compared with necropsy measurements of wall thickness, LV cross-sectional area, and volume. LV and right ventricular structures were well visualized in short-axis cross-sectional images in all animals, and images suitable for quantitative analysis were obtained in 92% of the periods. Coronary occlusion caused immediate, marked LV cavitary expansion, which rapidly returned to normal by 5 minutes of reperfusion. Active systolic thickening of the anterior wall at baseline (47% +/- 3%) became passive thinning during occlusion (-6% +/- 2%) and recovered partially, to 30% +/- 3% at 5 minutes of reperfusion and 42% +/- 4% at 60 minutes (p < 0.0005 at 5 minutes of reperfusion vs baseline; p not significant at 60 minutes). Recovery of thickening after 5 minutes of reperfusion was not different after the first versus third occlusion (23% +/- 4% vs 30% +/- 3%; p = 0.19). Measurements made by 2DE correlated well with those made by necropsy, although wall thickness was slightly thicker by 2DE. We conclude that epicardial echocardiography with an intravascular ultrasound catheter provides quantifiable 2DE images in this model and yields accurate information on segmental wall thickening and ventricular geometry not available by other techniques. Left coronary occlusion in the rat is associated with marked global and segmental LV expansion, which rapidly reverses with reperfusion. Postischemic regional wall motion abnormalities are present after coronary occlusion as brief as 2 minutes and can be measured accurately. The effect of multiple brief occlusions is not cumulative.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:7756001

Hagar, J M; Matthews, R; Kloner, R A

1995-01-01

132

Regional myocardial function during contiguous ischaemia in an anaesthetized canine model: comparison of six methods of measurement.  

PubMed

During acute myocardial ischaemia, the function of the unaffected muscle is the primary determinant of residual cardiac performance. We compared six methods of measuring regional function in the remaining non-ischaemic segment after acute ligation of the left anterior descending (LAD) coronary artery in 16 dogs. Preparation included left ventricular micromanometers, regional sonomicrometer transducers to measure segment length and wall thickness, caval occluders and left atrial catheters for injection of radioactive microspheres to measure regional blood flow. Pulmonary artery, central venous and systemic arterial pressures were measured and regional coronary venous blood was collected for direct myocardial oxygen consumption (VO2) calculations. Under basal high-dose fentanyl-neuromuscular blocker anaesthesia, the LAD was occluded after addition of halothane or isoflurane at 0.5 or 1.5 MAC concentrations. Regional myocardial function of the non-ischaemic segment was assessed by the following computer-derived indices: percent systolic wall thickening (% WT), velocity of shortening (vs), percent systolic shortening (%SS), regional stroke work (RSW), regional preload recruitable stroke work (RPRSW) and regional end-systolic elastance (Ees). No index demonstrated enhanced function in the non-ischaemic segment after LAD ligation and all monitors, except Ees, were sensitive to depression of function represented by a decrease in values after administration of halothane and isoflurane (P < 0.05). Ees values increased with the addition of isoflurane and remained constant with halothane. Circulating concentrations of catecholamines were unchanged after ischaemia, while inhalation agents caused a decrease in the concentrations of adrenaline and dopamine (P < 0.05), but not noradrenaline.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7946866

Reitan, J A; Kien, N D; Moore, P G; White, D A

1994-09-01

133

Autologous Cardiomyotissue Implant Promotes Myocardial Regeneration, Decreases Infarct Size and Improves Left Ventricular Function  

PubMed Central

Background Cell therapy for myocardial infarction (MI) may be limited by poor cell survival and lack of transdifferentiation. We report a novel technique of implanting whole autologous myocardial tissue from preserved myocardial regions into infarcted regions. Methods and Results Fourteen rats were used to optimize cardiomyotissue size using peritoneal wall implantation (300?M identified as optimal size). Thirty-nine pigs were used to investigate cardiomyotissue implantation in MI induced by LAD balloon occlusion [10 animals died, male to female transplantation for tracking with ISH for Y chromosome, n=4 (2-donors and 2-MI animals), acute MI implant cohort at 1 hour, n=13, and healed MI implant at 2 weeks, n=12]. Assessment included echocardiography, MRI, hemodynamics, TTC staining, histological, and molecular analysis. Tracking studies demonstrated viable implants with donor cells interspersed in the adjacent myocardium with gap junctions and desmosomes. In the acute MI cohort, treated animals compared to controls had improved perfusion by MRI (1.2±0.01 vs. 0.86±0.05,p<0.01), decreased MI size (MRI:%LV:2.2±0.5 vs. 5.4±1.5,p=0.04, TTC: %Anterior wall: 10.3±4.6 vs. 28.9±5.8,p<0.03), improved contractility (+dP/dt:1235±215 vs. 817±817,p<0.05). In healed MI cohort, treated animals had less decline in EF between 2 and 4 week assessment (-3±4% vs. -13±-4%,p<0.05), less decline in +/-dP/dt, and smaller MI (TTC: 21±11% vs. 3±8%,p=0.006) than control animals. Infarcts in the treated animals contained more mdr-1+ cells and fewer c-kit+ cells with a trend for decreased expression of MMP-2 and increased expression of TIMP-2. Conclusion Autologous cardiomyotissue implanted in myocardial infarction area remains viable, exhibits electromechanical coupling, decreases infarct size and improves LV function. PMID:21173354

Wykrzykowska, Joanna J.; Rosinberg, Audrey; Lee, Seung U.; Voisine, Pierre; Wu, Guifu; Appelbaum, Evan; Boodhwani, Munir; Sellke, Frank W.; Laham, Roger J.

2011-01-01

134

Nicardipine in models of myocardial infarction  

PubMed Central

1 In a dog model of partial myocardial ischaemia, superimposed ST segment elevations in epicardial ECGs were inhibited by nicardipine over a cumulative i.v. dose range of 1-20 ?g kg-1. 2 Over the cumulative i.v. dose range of 0.5-166.5 ?g kg-1, nicardipine had little overall effect on gross cardiac conduction, at spontaneous heart rate. 3 Dogs that received oral 1-2 mg kg-1 nicardipine daily for 16 weeks and then survived 1 week occlusion of the left anterior descending coronary artery (LAD) developed a superior coronary collateral circulation compared with untreated animals. 4 Nicardipine given by three different dosing schedules to baboons markedly limited myocardial infarction over a 6 h period of LAD occlusion. 5 Compared with a group of completely untreated dogs, there was protection of the myocardium in the animals given nicardipine that survived 3 months occlusion of the LAD. ImagesFigure 7 PMID:4027150

Alps, B. J.; Calder, C.; Wilson, A.

1985-01-01

135

Myocardial infarction following cannabis induced coronary vasospasm.  

PubMed

Smoking cannabis is a rare cause of myocardial infarction. We report a 29-year-old man who presented with acute coronary syndrome following consumption of a type of cannabis with the street name 'Kerala Ganja'. KG is smuggled into Sri Lanka from India; it is grown in the south Indian state of Kerala and is much more potent than the local ganja (marijuana). The patient developed dynamic ST-segment elevations in different leads in sequential ECGs, corresponding to different coronary artery territories. Coronary angiogram did not demonstrate evidence of occlusive atherosclerotic disease, but showed slow flow down the left anterior descending artery, which improved with administration of intracoronary nitrates. The patient's cardiac biomarkers were significantly elevated. A diagnosis was made of vasospasm causing myocardial infarction, most likely to have been triggered by cannabis consumption. We highlight the importance of considering this possible aetiology, particularly in patients with ACS with a susceptible social profile. PMID:25391827

Gunawardena, Mudalige Don Vajira Malin; Rajapakse, Senaka; Herath, Jagath; Amarasena, Naomali

2014-01-01

136

Microvascular Dysfunction, Myocardial Ischemia, and Progression to Heart Failure in Patients with Hypertrophic Cardiomyopathy  

Microsoft Academic Search

Microvascular dysfunction can be demonstrated in most patients with hypertrophic cardiomyopathy (HCM), both in the hypertrophied\\u000a and nonhypertrophied myocardial walls, mostly due to intimal and medial hyperplasia of the intramural coronary arteries and\\u000a subsequent lumen reduction. As a consequence, regional myocardial ischemia may be triggered by exercise, increased heart rate,\\u000a or arrhythmias, in areas which are unable to increase myocardial

Franco Cecchi; Aurelio Sgalambro; Massimo Baldi; Barbara Sotgia; Davide Antoniucci; Paolo G. Camici; Roberto Sciagrà; Iacopo Olivotto

2009-01-01

137

Myocardial fibre calcification  

Microsoft Academic Search

Three cases of myocardial fibre calcification found at post-mortem examination are described. In one case there was antemortem hypercalcaemia and hyperphosphataemia and the case was clearly an example of metastatic calcification. In the other two cases there was ischaemic myocardial necrosis and calcification was seen in fibres which were not overtly necrotic, but which were both in proximity to (the

J McClure; A S Pieterse; D J Pounder; P S Smith

1981-01-01

138

Can natural strain and strain rate quantify regional myocardial deformation? A study in healthy subjects  

Microsoft Academic Search

Strain rate (SR) and strain (?) have been proposed as new ultrasound (US) indices for quantifying regional wall deformation, and can be measured from color Doppler myocardial data by determining the local spatial velocity gradient. The aim of this study was to define normal regional SR\\/? values for both radial and longitudinal myocardial deformation. SR\\/? profiles were obtained from 40

Miros?aw Kowalski; Tomasz Kukulski; Fadi Jamal; Jan D’hooge; Frank Weidemann; Frank Rademakers; Bart Bijnens; Liv Hatle; George R Sutherland

2001-01-01

139

Hemin, inducer of heme-oxygenase 1, improves functional recovery from myocardial stunning in conscious dogs  

Microsoft Academic Search

Objective: To examine the effects of pretreatment with hemin, an inducer of the potential antioxidative enzyme heme-oxygenase 1 (HO-1) or heat-shock protein 32, on myocardial stunning. Design: Randomized animal study. Setting: Animal laboratory of a university hospital. Participants: Chronically instrumented mongrel dogs (n = 44). Interventions: Dogs underwent chronic instrumentation for measurement of hemodynamics and myocardial wall thickening fraction (WTF).

Thomas Peter Weber; Andreas Meissner; Peter Boknik; Maike Grosse Hartlage; Thomas Möllhoff; Hugo Van Aken; Norbert Rolf

2001-01-01

140

Anterior spinal artery syndrome  

Microsoft Academic Search

Three patients with symptoms due to the anterior spinal artery syndrome were treated by direct perfusion of dexamethasone sodium phosphate and urokinase into the artery of Adamkiewicz. Their symptoms were paraparesis with dissociated sensory loss and sphincter dysfunction, and there was no evidence of the possible cause. In the early phase of the disease, three consecutive injections were carried out

H. Baba; K. Tomita; T. Kawagishi; S. Imura

1993-01-01

141

Reverse left ventricular remodeling after acute myocardial infarction: the prognostic impact of left ventricular global torsion.  

PubMed

Reverse left ventricular (LV) remodeling (>10 % reduction in LV end-systolic volume) may occur in patients recovering for acute ST-elevation myocardial infarction (STEMI), undergoing percutaneous revascularization of infarct-related coronary artery (PCI). To detect whether LV global torsion obtained by two-dimensional speckle-tracking echocardiography was predictive of reverse LV remodeling, 75 patients with first anterior wall STEMI were studied before (T1) and after PCI (T2) and at 6-month follow-up. Two-year clinical follow-up was also accomplished. LV volumes and both LV sphericity index and conic index were obtained by three-dimensional echocardiography. Reverse remodeling was observed in 25 patients (33 %). By multivariate analysis, independent predictors of reverse LV remodeling were: LV conic index, T2 LV torsion and ? torsion (difference between T2 and T1 LV torsion expressed as percentage of this latter). According to receiver operating characteristic analysis, 1.34°/cm for T2 LV torsion (sensitivity 88 % and specificity 80 %) and 54 % for ? torsion (sensitivity 92 % and specificity 82 %) were the optimal cutoff values in predicting reverse LV remodeling. In up to 24 month follow-up, 4 non-fatal re-infarction, 7 hospitalization for heart failure and 4 cardiac deaths occurred. By multivariate Cox analysis, the best variable significantly associated with event-free survival rate was reverse LV remodeling with a hazard ratio = 9.9 (95 % confidence interval, 7.9-31.4, p < 0.01). In conclusion, reverse LV remodeling occurring after anterior wall STEMI is associated with favorable long-term outcome. The improvement of global LV torsion following coronary artery revascularization is the major predictor of reverse LV remodeling. PMID:23179752

Spinelli, Letizia; Morisco, Carmine; Assante di Panzillo, Emiliano; Izzo, Raffaele; Trimarco, Bruno

2013-04-01

142

Relationship of functional recovery to scar contraction after myocardial infarction in the canine left ventricle  

SciTech Connect

We have previously reported that regional wall motion abnormalities in a canine model of acute myocardial infarction may show substantial improvement in the first 6 weeks after infarction. To determine whether the mechanism of this improvement in function is the result of scar contraction within the infarct, we studied the relationship between changes in regional wall motion defined by cross-sectional echocardiography and the regional concentration of radioactive microspheres injected immediately before coronary occlusion and sampled 6 weeks after occlusion. Eight dogs underwent serial echocardiographic and microsphere blood flow measurements immediately before and 30 minutes, 48 hours, 1 week, 3 weeks, and 6 weeks after ligation of the left anterior descending or the left circumflex coronary artery. Wall motion and blood flow were measured in the short-axis section of the left ventricle at the level of the midpapillary muscle in each 10-degree radial segment around the circumference of the ventricle. Infarct histology was assessed at 6 weeks by means of the same radial coordinate system. Control data were collected in a similar manner from four dogs that underwent sham operations and had no histologic evidence of infarction. In all of the animals with infarcts, but not in the sham animals, the calculated preocclusion endocardial and epicardial blood flow values in the histologic infarct zone (252 +/- 44 and 168 +/- 17 ml/min/100 gm, respectively, mean +/- SEM) were significantly higher than those in the normal opposite wall (endocardial: 106 +/- 3 ml/min/100 gm, p less than 0.01); epicardial: 108 +/- 3 ml/min/100 gm, p less than 0.01. The location and circumferential extent of myocardium showing this elevation of preocclusion blood flow correlated well (r = 0.93, p less than 0.001) with the location and circumferential extent of the histologic infarct.

Choong, C.Y.; Gibbons, E.F.; Hogan, R.D.; Franklin, T.D.; Nolting, M.; Mann, D.L.; Weyman, A.E.

1989-04-01

143

Stress thallium-201 myocardial scintigraphy for the detection of individual coronary arterial lesions in patients with and without previous myocardial infarction  

SciTech Connect

The value of stress thallium-201 scintigraphy for detecting individual coronary arterial stenoses was analyzed in 141 patients with angiographically proved coronary artery disease, 101 with and 40 without a previous myocardial infarction. In patients without infarction, the sensitivity for detecting greater than 50 percent narrowing in the left anterior descending, the right and the left circumflex coronary artery was 66, 53 and 24 percent, respectively. In those with a previous infarction, the sensitivity for demonstrating disease in the artery corresponding to the site of infarction was 100 percent for the left anterior descending, 79 percent for the right and 63 percent for the left circumflex coronary artery. In patients with a prior anterior infarction, concomitant right or left circumflex coronary arterial lesions were detected in only 1 of 12 cases, whereas in those with previous inferior or inferolateral infarction, the sensitivity for left anterior descending coronary artery disease was 69 percent. Because of the reasonably high sensitivity for detecting left anterior descending arterial disease, irrespective of the presence and location of previous infarction, myocardial scintigraphy was useful in identifying multivessel disease in patients with a previous inferior infarction. However, because of its relative insensitivity for right or left circumflex coronary artery disease, scintigraphy proved to be a poor predictor of multivessel disease in patients with a prior anterior infarction and in patients without previous myocardial infarction.

Rigo, P.; Bailey, I.K.; Griffith, L.S.; Pitt, B.; Wagner, H.N. Jr.; Becker, L.C.

1981-08-01

144

Anterior exposure of the thoracic spine.  

PubMed

Spinal operation via an anterior thoracic approach is becoming increasingly common, and the thoracic surgeon is now being called upon to provide exposure for orthopedic and neurosurgical colleagues. We report experience with 126 such patients from 1982 through 1993. There were 61 male and 65 female patients (mean age, 39.0 years; range, 14 to 77 years). Indications were trauma in 45 patients (36%), spinal deformity in 42 (33%), cancer in 15 (12%), disc disease in 12 (10%), and infection in 12 (10%). Operative incisions included 22 (17%) right and 14 (11%) left thoracotomies, 33 (26%) right and 56 (44%) left thoracolumbar approaches, and one (1%) sternotomy. A prior spinal operation had been performed on 31 patients (25%), and 56 (44%) had a subsequent posterior spinal operation. Instrumentation was used in 38 (30%) and bone grafts in all but 6 patients. A neurologic deficit was present in 69 patients (55%) preoperatively and was improved in 67 patients postoperatively. Operative mortality was 3.2% (4 patients) due to myocardial infarction, stroke with pneumonia, adult respiratory distress syndrome, and malignant biliary obstruction. Univariate and multivariate risk analysis were performed. Only the diagnosis of osteomyelitis proved to be a significant (p = 0.0002) indicator of operative mortality, with 3 of 12 such patients dying (25%). These results suggest that anterior spinal exposure via thoracic approach is a major operation with considerable perioperative risk. Patients with osteomyelitis appear to be at increased risk for operative mortality. PMID:8010785

Naunheim, K S; Barnett, M G; Crandall, D G; Vaca, K J; Burkus, J K

1994-06-01

145

Treating anterior open bite  

Microsoft Academic Search

Data sourceThe Cochrane Central Register of Controlled Trials, Medline, Embase, LILACS (Latin American & Caribbean Health Sciences Literature) , Brazilian Bibliography of Odontology and SciELO. Ten Chinese journals were searched by hand and the bibliographies of papers were retrieved.Study selectionRandomised controlled trials (RCT) or quasi-RCT of orthodontic or orthopaedic treatments or both to correct anterior open bite in children were

Yijin Ren

2007-01-01

146

Primary ST changes. Diagnostic aid in paced patients with acute myocardial infarction.  

PubMed Central

In 34 out of 36 patients with apical right ventricular endocardial pacing, primary ischaemic ST alterations were observed during the early stage of acute myocardial infarction. These ST changes, indicating acute injury, were detected in the paced beats in inferior and in anterior infarct. The primary ST changes were consistent only during the early stages of acute myocardial infarction and were not detected when the electrode tip was not in the apex of the right ventricle. It is suggested that the primary ST changes should be used to diagnose acute myocardial infarction in paced patients. Images PMID:861092

Niremberg, V; Amikam, S; Roguin, N; Pelled, B; Riss, E

1977-01-01

147

Assessment of Transmural Distribution of Myocardial Perfusion With Contrast Echocardiography  

Microsoft Academic Search

Background—We hypothesized that by using our newly defined method of destroying microbubbles and measuring their rate of tissue replenishment, we could assess the transmural distribution of myocardial perfusion. Methods and Results—We studied 12 dogs before and after creation of left anterior descending coronary artery stenoses both at rest and during hyperemia (n562 stages). Microbubbles were administered as a constant infusion,

Andre Z. Linka; Jiri Sklenar; Kevin Wei; Ananda R. Jayaweera; Danny M. Skyba; Sanjiv Kaul

148

Myocardial stunning in hypertrophic cardiomyopathy: recovery predicted by single photon emission computed tomographic thallium-201 scintigraphy  

SciTech Connect

A young woman with hypertrophic cardiomyopathy confirmed by echocardiography and cardiac catheterization presented with chest pain and features of a large left ventricular aneurysm. The initial diagnosis was myocardial ischemia with either an evolving or an ancient myocardial infarction. Subsequently, verapamil therapy was associated with complete resolution of the extensive left ventricular wall motion abnormalities, normalization of left ventricular ejection fraction and a minimal myocardial infarction. Normal thallium uptake on single photon emission computed tomographic scintigraphy early in the hospital course predicted myocardial viability in the region of the aneurysm. Thus, orally administered verapamil may reverse spontaneous extensive myocardial ischemia in hypertrophic cardiomyopathy and possibly limit the extent of myocardial infarction in such circumstances.

Fine, D.G.; Clements, I.P.; Callahan, M.J.

1989-05-01

149

Removal of a giant intrathoracic cyst from the anterior mediastinum.  

PubMed

A 45-year-old caucasian man with progressive dyspnea appeared to have a giant intrathoracic cyst in the anterior mediastinum encasing the heart and compressing both lungs. He underwent succesful removal of the cyst through a median sternotomy. Recovery was uneventful. Gross examination revealed a thin-walled cyst filled with clear fluid. Microscopic histopathologic examination revealed a cyst wall lined by cubic cells and underlying loose connective tissue with remnants of thymic tissue. The definitive diagnosis was an intrathoracic (simple) mesothelial cyst. An intrathoracic mesothelial cyst is a benign, generally asymptomatic tumor that can be located in the anterior cardiophrenic angle, the paravertebral or paratracheal regions, or in the anterior mediastinum. It can become rather large before it becomes symptomatic, at which point surgical removal is generally warranted. PMID:25239838

Bouma, Wobbe; Klinkenberg, Theo J; Van De Wauwer, Caroline; Timens, Wim; Mariani, Massimo A

2014-01-01

150

Anterior interosseous nerve syndrome  

PubMed Central

Objective: We sought to determine lesion sites and spatial lesion patterns in spontaneous anterior interosseous nerve syndrome (AINS) with high-resolution magnetic resonance neurography (MRN). Methods: In 20 patients with AINS and 20 age- and sex-matched controls, MRN of median nerve fascicles was performed at 3T with large longitudinal anatomical coverage (upper arm/elbow/forearm): 135 contiguous axial slices (T2-weighted: echo time/repetition time 52/7,020 ms, time of acquisition: 15 minutes 48 seconds, in-plane resolution: 0.25 × 0.25 mm). Lesion classification was performed by visual inspection and by quantitative analysis of normalized T2 signal after segmentation of median nerve voxels. Results: In all patients and no controls, T2 lesions of individual fascicles were observed within upper arm median nerve trunk and strictly followed a somatotopic/internal topography: affected were those motor fascicles that will form the anterior interosseous nerve further distally while other fascicles were spared. Predominant lesion focus was at a mean distance of 14.6 ± 5.4 cm proximal to the humeroradial joint. Discriminative power of quantitative T2 signal analysis and of qualitative lesion rating was high, with 100% sensitivity and 100% specificity (p < 0.0001). Fascicular T2 lesion patterns were rated as multifocal (n = 17), monofocal (n = 2), or indeterminate (n = 1) by 2 independent observers with strong agreement (kappa = 0.83). Conclusion: It has been difficult to prove the existence of fascicular/partial nerve lesions in spontaneous neuropathies using clinical and electrophysiologic findings. With MRN, fascicular lesions with strict somatotopic organization were observed in upper arm median nerve trunks of patients with AINS. Our data strongly support that AINS in the majority of cases is not a surgically treatable entrapment neuropathy but a multifocal mononeuropathy selectively involving, within the main trunk of the median nerve, the motor fascicles that continue distally to form the anterior interosseous nerve. PMID:24415574

Baumer, Philipp; Meinck, Hans-Michael; Schiefer, Johannes; Weiler, Markus; Bendszus, Martin; Kele, Henrich

2014-01-01

151

Evaluating anterior knee pain.  

PubMed

Musculoskeletal complaints account for about 20% to 30% of all primary care office visits; of these visits, discomfort in the knee, shoulder, and back are the most prevalent musculoskeletal symptoms. Having pain or dysfunction in the front part of the knee is a common presentation and reason for a patient to see a health care provider. There are a number of pathophysiological etiologies to anterior knee pain. This article describes some of the common and less common causes, and includes sections on diagnosis and treatment for each condition as well as key points. PMID:24994047

Hong, Engene; Kraft, Michael C

2014-07-01

152

JAMA Patient Page: Myocardial Infarction  

MedlinePLUS

... of the American Medical Association JAMA PATIENT PAGE Myocardial Infarction M yocardial infarction , also known as a heart attack, can strike without warning. A myocardial infarction occurs when blood supply to a part of ...

153

Magnetic targeting enhances retrograde cell retention in a rat model of myocardial infarction  

PubMed Central

Introduction Retrograde coronary venous infusion is a promising delivery method for cellular cardiomyoplasty. Poor cell retention is the major obstacle to the establishment of this method as the preferred route for cell delivery. Here, we explored whether magnetic targeting could enhance retrograde cell retention in a rat model of myocardial infarction. Methods Rat mesenchymal stem cells were labeled with superparamagnetic oxide nanoparticles. The magnetic responsiveness of MSCs was observed while cells flowed through a tube that served as a model of blood vessels in a 0.6-Tesla magnetic field. In a Sprague–Dawley rat model of acute myocardial infarction, 1?×?106 magnetic mesenchymal stem cells were transjugularly injected into the left cardiac vein while a 0.6-Tesla magnet was placed above the heart. The cardiac retention of transplanted cells was assessed by using quantitative Y chromosome-specific polymerase chain reaction, cardiac magnetic resonance imaging, and optical imaging. Cardiac function was measured by using echocardiography, and histologic analyses of infarct morphology and angiogenesis were obtained. Results The flowing iron oxide-labeled mesenchymal stem cells were effectively attracted to the area where the magnet was positioned. Twenty-four hours after cellular retrocoronary delivery, magnetic targeting significantly increased the cardiac retention of transplanted cells by 2.73- to 2.87-fold. Histologic analyses showed that more transplanted cells were distributed in the anterior wall of the left ventricle. The enhanced cell engraftment persisted for at least 3 weeks, at which time, left ventricular remodeling was attenuated, and cardiac function benefit was improved. Conclusions These results suggest that magnetic targeting offers new perspectives for retrograde coronary venous delivery to enhance cell retention and subsequent functional benefit in heart diseases. PMID:24330751

2013-01-01

154

Myocardial Lineage Development  

PubMed Central

The myocardium of the heart is composed of multiple highly specialized myocardial lineages, including those of the ventricular and atrial myocardium, and the specialized conduction system. Specification and maturation of each of these lineages during heart development is a highly ordered, ongoing process involving multiple signaling pathways and their intersection with transcriptional regulatory networks. Here, we attempt to summarize and compare much of what we know about specification and maturation of myocardial lineages from studies in several different vertebrate model systems. To date, most research has focused on early specification, and while there is still more to learn, less is known about factors that promote subsequent maturation of myocardial lineages required to build the functioning adult heart. PMID:21148449

Evans, Sylvia M.; Yelon, Deborah; Conlon, Frank L.; Kirby, Margaret L.

2010-01-01

155

Bioengineered anterior cruciate ligament  

NASA Technical Reports Server (NTRS)

The present invention provides a method for producing an anterior cruciate ligament ex vivo. The method comprises seeding pluripotent stem cells in a three dimensional matrix, anchoring the seeded matrix by attachment to two anchors, and culturing the cells within the matrix under conditions appropriate for cell growth and regeneration, while subjecting the matrix to one or more mechanical forces via movement of one or both of the attached anchors. Bone marrow stromal cells are preferably used as the pluripotent cells in the method. Suitable matrix materials are materials to which cells can adhere, such as a gel made from collagen type I. Suitable anchor materials are materials to which the matrix can attach, such as Goinopra coral and also demineralized bone. Optimally, the mechanical forces to which the matrix is subjected mimic mechanical stimuli experienced by an anterior cruciate ligament in vivo. This is accomplished by delivering the appropriate combination of tension, compression, torsion, and shear, to the matrix. The bioengineered ligament which is produced by this method is characterized by a cellular orientation and/or matrix crimp pattern in the direction of the applied mechanical forces, and also by the production of collagen type I, collagen type III, and fibronectin proteins along the axis of mechanical load produced by the mechanical forces. Optimally, the ligament produced has fiber bundles which are arranged into a helical organization. The method for producing an anterior cruciate ligament can be adapted to produce a wide range of tissue types ex vivo by adapting the anchor size and attachment sites to reflect the size of the specific type of tissue to be produced, and also adapting the specific combination of forces applied, to mimic the mechanical stimuli experienced in vivo by the specific type of tissue to be produced. The methods of the present invention can be further modified to incorporate other stimuli experienced in vivo by the particular developing tissue, some examples of the stimuli being chemical stimuli, and electro-magnetic stimuli. Some examples of tissue which can be produced include other ligaments in the body (hand, wrist, elbow, knee), tendon, cartilage, bone, muscle, and blood vessels.

Altman, Gregory (Inventor); Kaplan, David (Inventor); Vunjak-Novakovic, Gordana (Inventor); Martin, Ivan (Inventor)

2001-01-01

156

Inhalation of Concentrated Ambient Air Particles Exacerbates Myocardial Ischemia in Conscious Dogs  

Microsoft Academic Search

Short-term increases in ambient air pollution have been associated with an increased incidence of acute cardiac events. We assessed the effect of inhalation exposure to concentrated ambient parti- cles (CAPs) on myocardial ischemia in a canine model of coronary artery occlusion. Six mongrel dogs underwent thoracotomy for implantation of a vascular occluder around the left anterior descending coronary artery and

Gregory A. Wellenius; Brent A. Coull; John J. Godleski; Petros Koutrakis; Kazunori Okabe; Sara T. Savage; Joy E. Lawrence; G. G. Krishna Murthy; Richard L. Verrier

2002-01-01

157

Acute myocardial infarction caused by paradoxical coronary embolization in a patient with a patent foramen ovale  

Microsoft Academic Search

We describe the case of a young woman without cardiac risk factors who had an acute inferoapical myocardial infarction. Coronary angiographic appearance was consistent with thrombus in the distal left anterior descending coronary artery. A patent foramen ovale with moderate right-to-left shunting after the Valsalva maneuver was detected by contrast transesophageal echocardiography. No other cardioembolic source was identified. Paradoxical embolization

Deborah R Gersony; Sang H Kim; Marco Di Tullio; Ali Fard; Leroy Rabbani; Shunichi Homma

2001-01-01

158

ECG findings after myocardial infarction in children after Kawasaki disease  

SciTech Connect

Standard 12-lead ECGs were evaluated in 17 children with myocardial infarction and 78 children without myocardial infarction after Kawasaki disease; sensitivity and specificity of the ECG infarction criteria were determined. The presence or absence of myocardial infarction was determined from either clinical examination results (coronary angiography, ventriculography, and thallium-201 myocardial imaging) or autopsy findings. Of seven patients with inferior infarction, abnormally deep Q waves in lead II, III, or aVF were observed in six, but the duration was greater than 0.04 second in only one (14%). The sensitivity and specificity of inferior infarction criteria based on Q wave amplitude were 86% and 97%, respectively. Of eight patients with anterior infarction, seven (88%) had abnormally deep and wide (greater than or equal to 0.04 second) Q waves in anterior chest leads. The sensitivity and specificity of the infarction criteria based on the amplitude and duration of the Q wave were 75% and 99%, respectively. Of seven patients with lateral infarction, Q waves were observed in lead I, aVL, or both in four patients, and in all of these patients Q waves were wider than 0.04 second. In two patients with both inferior and anterior infarction, Q waves were observed only in leads II, III, and aVF; in only one patient were the Q waves wider than 0.04 second. Thus deep Q waves in lead II, III, or aVF that are not wider than 0.04 second may indicate inferior infarction in children. Q waves in lead I, aVL, and chest leads associated with anterolateral infarction are in most instances deep and wide.

Nakanishi, T.; Takao, A.; Kondoh, C.; Nakazawa, M.; Hiroe, M.; Matsumoto, Y.

1988-10-01

159

[Anterior sacral meningomyelocele].  

PubMed

Anterior sacral meningomyelocele is the rarest and least known form of congenital myelocele. It is not manifested externally, it is usually not attended with changes in the neurologic status, and may be regarded as a presacral dermoid cyst. The authors observed 5 members of one family with similar clinical and X-ray signs of such herniations, in 2 they were verified. The presence of cystic structures in the cavity of the small pelvis in conjunction with a congenital defect in the bodies of the sacral vertebrae is an indication for conducting pneumomyelography so as to make a more precise diagnosis. A study of the hereditary and family history is a necessary trend in the examination of such patients because the disease may be of a familial character. PMID:919974

Solopaev, A A; Myl'nikov, P I; Gerber, Iu M; Riazantsev, P N

1977-01-01

160

Ischemia-induced alterations in myocardial (Na+ + K+)-ATPase and cardiac glycoside binding.  

PubMed Central

The effects of ischemia on the canine myocardial (Na+ + K+)-ATPase complex were examined in terms of alterations in cardiac glycoside binding and enzymatic activity. Ability of the myocardial cell to bind tritiated ouabain in vivo was assessed after 1, 2, and 6 h of coronary occlusion followed by 45 min of reperfusion, and correlated with measurements of in vitro (Na+ + K+)-ATPase activity and in vitro [3H]ouabain binding after similar periods of ischemia. Regional blood flow alterations during occlusion and reperfusion were simultaneously determined utilizing 15 mum radioactive microspheres to determine the degree to which altered binding of ouabain might be flow related. Anterior wall infarction was produced in 34 dogs by snaring of confluent branches of the left coronary system. Epicardial electrograms delineated ischemic and border zone areas. Coronary reperfusion after 2 and 6 h of occlusion was associated with impaired reflow of blood and markedly impaired uptake of [3H]ouabain in ischemic myocardium. In both groups, in vivo [3H]ouabain binding by ischemic tissue was reduced out of proportion to the reduction in flow. Despite near-complete restoration of flow in seven dogs occluded for 1 h and reperfused, [3H]ouabain remained significantly reduced to 58 +/- 9% of nonischemic uptake in subendocardial layers of the central zone of ischemia. Thus, when coronary flow was restored to areas of myocardium rendered acutely ischemia for 1 or more hours, ischemic zones demonstrated progressively diminished ability to bind ouabain. To determine whether ischemia-induced alteration in myocardial (Na+ + K+)-ATPase might underlie these changes, (Na+ + K+)-ATPase activity and [3H]ouabain binding were measured in microsomal fractions from ischemic myocardium after 1, 2, and 6 h of coronary occlusion. In animals occluded for 6 h, (Na+ + K+)-ATPase activity was significantly reduced by 40% in epicardial and by 35% in endocardial layers compared with nonischemic myocardium. Comparable reductions in in vitro [3H]ouabain binding were also demonstrated. Reperfusion for 45 min after occlusion for 6 h resulted in no significant restoration of enzyme activity when compared to the nonreperfused animals. In six animals occluded for 2 h, a time at which myocardial creatine phosphokinase activity remains unchanged, (Na+ + K+)-ATPase activity was reduced by 25% compared with nonischemic enzyme activity. In five dogs occluded for 1 h, (Na+ + K+)-ATPase activity in ischemic myocardium was unchanged from control levels. We conclude that reduced regional myocardial blood flow, local alterations in cellular milieu, and altered glycoside-binding properties of (Na+ + K+)-ATPase all participate in the reduction of cardiac glycoside binding observed after reperfusion of ischemic myocardium. In addition, after 2 or more hours of severe ischemia, myocardial (Na+ + K+)-ATPase catalytic activity is significantly reduced despite incubation in the presence of optimal substrate concentrations. Images PMID:130383

Beller, G A; Conroy, J; Smith, T W

1976-01-01

161

Myocardial infarction and weather.  

PubMed

The association of meterological factors with acute myocardial infarction was studied within a one-year period in Helsinki. Seasonal variation was found with the lowest incidence in summer and the highest in late autumn. Environmental temperature was not significantly correlated with the incidence of myocardial infarction but the case fatality rate was higher on coldest days. Atmospheric pressure turned out to be the meteorological variable with the highest correlation with the occurrence of myocardial infarction. Rapid decrease in atmospheric pressure was also associated with increased incidence of acute myocardial infarction. Relative humidity had little independent effect. The weather types with highest and lowest risk of heart attack were determined by the combined use of factor and cluster analysis. The most unfavourable turned out to be a relatively cold and moist weather with low atmospheric pressure, common in Helsinki during early winter and late autumn. The incidence of infarction did not increase on typical cold and dry winter days. The most favourable weather was warm, dry and stable summer weather. The difference in incidences between most and least favourable weather types was three-fold. PMID:616207

Sarna, S; Romo, M; Siltanen, P

1977-08-01

162

Myocardial gene therapy  

Microsoft Academic Search

Gene therapy is proving likely to be a viable alternative to conventional therapies in coronary artery disease and heart failure. Phase 1 clinical trials indicate high levels of safety and clinical benefits with gene therapy using angiogenic growth factors in myocardial ischaemia. Although gene therapy for heart failure is still at the pre-clinical stage, experimental data indicate that therapeutic angiogenesis

Jeffrey M. Isner

2002-01-01

163

Alterations in Transmural Myocardial Strain An Early Marker of Left Ventricular Dysfunction in Mitral Regurgitation?  

PubMed Central

Background In asymptomatic patients with severe isolated mitral regurgitation (MR), identifying the onset of early left ventricular (LV) dysfunction can guide the timing of surgical intervention. We hypothesized that changes in LV transmural myocardial strain represent an early marker of LV dysfunction in an ovine chronic MR model. Methods and Results Sheep were randomized to control (CTRL, n=8) or experimental (EXP, n=12) groups. In EXP, a 3.5- or 4.8-mm hole was created in the posterior mitral leaflet to generate “pure” MR. Transmural beadsets were inserted into the lateral and anterior LV wall to radiographically measure 3-dimensional transmural strains during systole and diastolic filling, at 1 and 12 weeks postoperatively. MR grade was higher in EXP than CTRL at 1 and 12 weeks (3.0 [2–4] versus 0.5 [0–2]; 3.0 [1–4] versus 0.5 [0–1], respectively, both P<0.001). At 12 weeks, LV mass index was greater in EXP than CTRL (201±18 versus 173±17 g/m2; P<0.01). LVEDVI increased in EXP from 1 to 12 weeks (P=0.015). Between the 1 and 12 week values, the change in BNP (?4.5±4.4 versus ?3.0±3.6 pmol/L), PRSW (9±13 versus 23±18 mm Hg), tau (?3±11 versus ?4±7 ms), and systolic strains was similar between EXP and CTRL. The changes in longitudinal diastolic filling strains between 1 and 12 weeks, however, were greater in EXP versus CTRL in the subendocardium (lateral: ?0.08±0.05 versus 0.02±0.14; anterior: ?0.10±0.05 versus ?0.02±0.07, both P<0.01). Conclusions Twelve weeks of ovine “pure” MR caused LV remodeling with early changes in LV function detected by alterations in transmural myocardial strain, but not by changes in BNP, PRSW, or tau. PMID:18824764

Carlhäll, Carl J.; Nguyen, Tom C.; Itoh, Akinobu; Ennis, Daniel B.; Bothe, Wolfgang; Liang, David; Ingels, Neil B.; Miller, D. Craig

2009-01-01

164

Takotsubo-Like Myocardial Dysfunction Accompanied with Cerebellar Hemorrhage  

PubMed Central

We report a 71-year-old woman with takotsubo-like myocardial dysfunction accompanied with cerebellar hemorrhage. On admission time, although she was unconscious by cerebellar hemorrhage, no obvious heart failure and serological disorder were observed. Three days later, operation for extraventricular drainage was performed. However, conscious level did not change. Four days after admission, the change of electrocardiogram wave pattern and the decrement of heart wall motion were detected. These findings revealed takotsubo-like myocardial dysfunction had occurred. Physical stresses by cerebellar hemorrhage and cranial operation might cause cardiac disorder. This is a remarkable case of takotsubo-like myocardial dysfunction, which is brought about cerebellar hemorrhage against subarachnoid hemorrhage. PMID:22953089

Tempaku, Akira; Kanda, Tsugiyasu

2012-01-01

165

Anterior ankle arthrodesis  

PubMed Central

Ankle arthrodesis is a common procedure that resolves many conditions of the foot and ankle; however, complications following this procedure are often reported and vary depending on the fixation technique. Various techniques have been described in the attempt to achieve ankle arthrodesis and there is much debate as to the efficiency of each one. This study aims to evaluate the efficiency of anterior plating in ankle arthrodesis using customised and Synthes TomoFix plates. We present the outcomes of 28 ankle arthrodeses between 2005 and 2012, specifically examining rate of union, patient-reported outcomes scores, and complications. All 28 patients achieved radiographic union at an average of 36 wk; the majority of patients (92.86%) at or before 16 wk, the exceptions being two patients with Charcot joints who were noted to have bony union at a three year review. Patient-reported outcomes scores significantly increased (P < 0.05). Complications included two delayed unions as previously mentioned, infection, and extended postoperative pain. With multiple points for fixation and coaxial screw entry points, the contoured customised plate offers added compression and provides a rigid fixation for arthrodesis stabilization. PMID:24649408

Slater, Gordon L; Sayres, Stephanie C; O’Malley, Martin J

2014-01-01

166

Deep anterior lamellar Keratoplasty  

PubMed Central

Keratoconus is a disease causing increased steepening of the cornea resulted in irregular astigmatism. Treatment options are Glasses, Hard contact lenses, Cross linking, Intracorneal Segments insertion, Refractive surgery (Gilda et al., 2008), or Keratoplasty. Lamellar Keratoplasty (LKP) can be a better choice to manage cases of moderate and some cases of severe Keratoconus without deep scarring and severe thinning, also in cases of corneal scarring not involving the deeper layers of the cornea. LKP is a corneal graft technique consisting of transplantation of partial-thickness donor tissue, devoid of endothelium, Descemet membrane (DM), and rear stroma into a recipient healthy stromal bed after dissection of pathologic anterior stroma. However, deep lamellar Keratoplasty (DLKP) is a surgical method that completely removes pathologic corneal stroma tissue down to the DM, followed by transplantation of donor cornea without endothelium over the host bed. DLKP has a number of advantages over penetrating Keratoplasty (PKP). Because it does not violate the intraocular structures of the eye, it diminishes or eliminates the chance of postoperative glaucoma, cataract formation, retinal detachment, cystoids macular edema, expulsive choroidal hemorrhage and epithelial ingrowths. Furthermore, this procedure avoids the replacement of host endothelium with donor endothelium and thus precludes endothelial graft rejection, with comparable visual outcomes and low rate of chronic endothelial cell loss compared to PKP. PMID:23960861

Al-Kharashi, Soliman A.; Al-Obailan, Majed M.; Almohaimeed, Mansour; Al-Torbak, Abdullah A.

2009-01-01

167

Sex-specific criteria for interpretation of thallium-201 myocardial uptake and washout studies  

SciTech Connect

A study was undertaken to determine the effect of gender on criteria for the quantitative analysis of exercise-redistribution /sup 201/Tl myocardial scintigraphy. The studies of 26 normal females and 23 normal males were subjected to bilinear interpolative background subtraction and horizontal profile analysis. Significant sexual differences were found in both regional uptake ratios and washout rates. These differences primarily reflected a proportionately decreased anterior and upper septal uptake in females, and faster washout in females. Faster myocardial /sup 201/Tl washout rates in females could not be clearly ascribed to either a physiological or artifactual explanation. It is concluded that since important differences exist between males and females in the detected pattern of /sup 201/Tl myocardial uptake and washout, sex-specific criteria may enhance the predictive accuracy of exercise-redistribution /sup 201/Tl myocardial scintigraphy.

Rabinovitch, M.; Suissa, S.; Elstein, J.; Staniloff, H.; Tang, A.; Rush, C.; Aldis, A.; Tannous, R.; Turek, M.; Addas, A.

1986-12-01

168

Perioperative assessment of myocardial deformation.  

PubMed

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 that 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 by 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 s. 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

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

2014-03-01

169

Myocardial electrical activity does not affect myocardial electrical impedance measurements  

Microsoft Academic Search

Objective  Myocardial electrical impedance (MEI) has shown to be an effective indicator of myocardial ischemia. We have previously developed\\u000a a novel monitor for measuring MEI in near-real time. The object of this study was to test whether drug-induced changes in\\u000a the frequency of the periodic myocardial electrical activity, as measured by the heart rate (HR), affect MEI measurements\\u000a made with our

Roger Dzwonczyk; Carlos del Rio; Thomas D. McSweeney; Xiaoli Zhang; Michael B. Howie

2009-01-01

170

Reversibility by dipyridamole of thallium-201 myocardial scan defects in patients with sarcoidosis  

SciTech Connect

In order to clarify the significance of anginal pain and myocardial thallium-201 scan defects in cardiac sarcoidosis, the pharmacologic effect of dipyridamole on myocardial perfusion was assessed by planar thallium-201 myocardial scintigraphy in patients with sarcoidosis. Thallium-201 myocardial scintigraphy was performed at rest and after 0.56 mg/kg intravenous dipyridamole during four minutes in 16 patients with sarcoidosis. The myocardial scan (45-degree and 70-degree left anterior oblique, and anterior views) was divided into 15 segments. Results were evaluated by the number of segmental defects and with a global perfusion score (from 0 to 60) by a semi-quantitative index depending on the size and severity of myocardial thallium-201 defects. Thirteen of the 16 patients showed partial or total reversion of their thallium-201 defects on redistribution scanning either at rest or after dipyridamole. The mean (+/- SD) number of myocardial perfusion defects that were present in all the patients decreased from 5.31 +/- 1.78 at rest to 3.25 +/- 2.52 after redistribution (p less than 0.001) and to 2.19 +/- 2.10 after dipyridamole (p less than 0.001). The mean global perfusion score increased from 53.2 +/- 3.0 at rest to 56.2 +/- 2.9 after redistribution (p less than 0.001) and to 57.2 +/- 2.7 after dipyridamole (p less than 0.001). A significant correlation (r = 0.82, p less than 0.001) was found between the increase of global perfusion score on redistribution and after dipyridamole. The reversibility of myocardial scan defects is a common finding in sarcoidosis. It makes unlikely the role of scar fibrosis or extensive confluent granulomas as a mechanism for such defects. The effect of dipyridamole suggests the presence of reversible disorders lying at the coronary microvascular level.

Tellier, P.; Paycha, F.; Antony, I.; Nitenberg, A.; Valeyre, D.; Foult, J.M.; Battesti, J.P.

1988-08-01

171

Effect of reperfusion and hyperemia on the myocardial distribution of technetium-99m t-butylisonitrile  

SciTech Connect

Technetium-99m t-butylisonitrile ((/sup 99m/Tc)TBI) is a promising new radiotracer for myocardial imaging. Its myocardial uptake is sufficiently high in humans to permit planar, tomographic, and gated images of excellent technical quality. We studied the behavior of (/sup 99m/Tc)TBI in the dog at rest and under conditions of hyperemia and reperfusion in order to determine the relationship between (/sup 99m/Tc)TBI myocardial concentration and blood flow. After permanent occlusion of the left anterior descending artery, the correlation between the relative myocardial concentration of (/sup 99m/Tc)TBI and regional myocardial blood flow (RMBF) measured with radiolabeled microspheres was excellent. In a dog model of transient hyperemia, the concentration of (/sup 99m/Tc)TBI was directly related to blood flow but underestimated the degree of hyperemia. Technetium-99m TBI redistributed into transiently ischemic myocardium. The myocardial concentrations of (/sup 99m/Tc)TBI and thallium-201(/sup 201/TI) in transiently ischemic myocardium were similar at 10 and 30 min following reperfusion and were significantly higher than blood flow prior to reperfusion. When (/sup 99m/Tc)TBI was injected into the left anterior descending artery, the washout was slow, falling to 78% of initial activity at 120 min after injection. In conclusion, (/sup 99m/Tc)TBI reflects regional myocardial blood flow accurately in ischemic and normal resting myocardium and underestimates blood flow at high flows. The rate of myocardial redistribution after reperfusion is similar for (/sup 99m/Tc)TBI and /sup 201/TI.

Holman, B.L.; Campbell, C.A.; Lister-James, J.; Jones, A.G.; Davison, A.; Kloner, R.A.

1986-07-01

172

Thallium myocardial perfusion scans for the assessment of right ventricular hypertrophy in patients with cystic fibrosis. A comparison with other noninvasive techniques  

SciTech Connect

The incidence of right ventricular hypertrophy in 32 patients with cystic fibrosis was studied using thallium 201 (TI-201) myocardial perfusion scans, and compared with other noninvasive techniques including electrocardiography, vectorcardiography, and M-mode echocardiography. The patients (mean age, 17.3 yr; range, 7 to 33) had a wide range of clinical and pulmonary abnormalities (mean Shwachman-Kulczycki score, 66.6). In the total study group, TI-201 scans, like the vectorcardiograms and the M-mode echocardiograms, gave a surprisingly high proportion of positive predictions for right ventricular hypertrophy (RVH) (44%). The correlations with all other noninvasive methods were uniformly poor, so caution must be exercised in using this technique to predict early RVH in order to follow the natural history of cor pulmonale in cystic fibrosis. At the time of the study, 6 patients had clinical evidence of right ventricular failure, and in this disease setting must have had RVH. In 3 patients, RVH was confirmed at autopsy, and it was successfully predicted by TI-201 scans in 5 of the 6 patients. The false negative scan may have been due to regional myocardial ischemia secondary to severe right ventricular failure. In contrast, the vectorcardiogram, using Fowler's new criteria, made a successful prediction of RVH in all 6 patients, and the electro cardiogram in only 3. Although the M-mode echocardiogram was abnormal in all patients, it would have predicted RVH (with increased right ventricular anterior wall thickness) in only 1 patient. We concluded that TI-201 myocardial perfusion cans are good at confirming RVH in cases with established right ventricular failure, but have no advantage over vectorcardiographic assessments, which are logistically easier to perform and carry no radiation risks.

Newth, C.J.; Corey, M.L.; Fowler, R.S.; Gilday, D.L.; Gross, D.; Mitchell, I.

1981-01-01

173

Quantitative Assessment of Regional Wall Motion Abnormalities Using Dual-Energy Digital Subtraction Intravenous Ventriculography  

NASA Astrophysics Data System (ADS)

Healthy portions of the left ventricle (LV) can often compensate for regional dysfunction, thereby masking regional disease when global indices of LV function are employed. Thus, quantitation of regional function provides a more useful method of assessing LV function, especially in diseases that have regional effects such as coronary artery disease. This dissertation studied the ability of a phase -matched dual-energy digital subtraction angiography (DE -DSA) technique to quantitate changes in regional LV systolic volume. The potential benefits and a theoretical description of the DE imaging technique are detailed. A correlated noise reduction algorithm is also presented which raises the signal-to-noise ratio of DE images by a factor of 2 -4. Ten open-chest dogs were instrumented with transmural ultrasonic crystals to assess regional LV function in terms of systolic normalized-wall-thickening rate (NWTR) and percent-systolic-thickening (PST). A pneumatic occluder was placed on the left-anterior-descending (LAD) coronary artery to temporarily reduce myocardial blood flow, thereby changing regional LV function in the LAD bed. DE-DSA intravenous left ventriculograms were obtained at control and four levels of graded myocardial ischemia, as determined by reductions in PST. Phase-matched images displaying changes in systolic contractile function were created by subtracting an end-systolic (ES) control image from ES images acquired at each level of myocardial ischemia. The resulting wall-motion difference signal (WMD), which represents a change in regional systolic volume between the control and ischemic states, was quantitated by videodensitometry and compared with changes in NWTR and PST. Regression analysis of 56 data points from 10 animals shows a linear relationship between WMD and both NWTR and PST: WMD = -2.46 NWTR + 13.9, r = 0.64, p < 0.001; WMD = -2.11 PST + 18.4, r = 0.54, p < 0.001. Thus, changes in regional ES LV volume between rest and ischemic states, as measured using the described imaging technique, appear linearly related to changes in wall-thickening, as measured using transmural ultrasonic crystals. This type of image analysis may prove useful in a variety of clinical and research applications and further investigation is proposed.

McCollough, Cynthia H.

174

Myocardial gene therapy  

NASA Astrophysics Data System (ADS)

Gene therapy is proving likely to be a viable alternative to conventional therapies in coronary artery disease and heart failure. Phase 1 clinical trials indicate high levels of safety and clinical benefits with gene therapy using angiogenic growth factors in myocardial ischaemia. Although gene therapy for heart failure is still at the pre-clinical stage, experimental data indicate that therapeutic angiogenesis using short-term gene expression may elicit functional improvement in affected individuals.

Isner, Jeffrey M.

2002-01-01

175

Anterior Knee Pain (Chondromalacia Patellae).  

ERIC Educational Resources Information Center

This article presents a pragmatic approach to the definition, diagnosis, and management of anterior knee pain. Symptoms and treatment are described. Emphasis is on active involvement of the patient in the rehabilitation exercise program. (IAH)

Garrick, James G.

1989-01-01

176

Imaging of anterior mediastinal tumours  

PubMed Central

Abstract Anterior mediastinal tumours include primary and secondary tumours. Patients may be asymptomatic or present with symptoms related to local tumour invasion or systemic symptoms due to release of hormones/cytokines or antibodies. The most common symptoms at presentation include chest pain, dyspnoea, cough, fever and chills. Despite rapid developments in imaging techniques, accurate staging of anterior mediastinal tumours remains a diagnostic quandary. Multimodality imaging plays an important role in determining surgical resectability and/or impact on subsequent management. This article briefly discusses the epidemiology and incidence of anterior mediastinal tumours and describes the role of imaging in tumour characterization and staging in detail. We focus on the more commonly encountered anterior mediastinal tumours. PMID:23131900

Ching Ong, Ching

2012-01-01

177

Myocardial capillaries in the fetal and the neonatal rat: a morphometric analysis of the maturing myocardial capillary bed.  

PubMed

Developing myocardial capillaries from 16-day-gestation fetus to adult undergo several morphological changes including a thinning of the lateral extensions of the capillary endothelial cells, the formation of a basal lamina, and an increase in the number of plasmalemmal vesicles. A decrease in the extracellular space, an increase in the number of capillaries, and a decrease in the capillary diameter were also observed during the developmental period. In view of these ultrastructural changes, a morphometric analysis was made on the developing myocardial wall to demonstrate specific quantitative changes. The volumes which were occupied by capillary endothelial cells, capillary lumina, extracellular space, and myocardial myocytes within a reference volume of myocardium were measured; and we found that 8% of the reference myocardial volume was occupied by capillary endothelial cells, 85% was occupied by myocardial myocytes, 4% was occupied by capillary lumina, and, except for a significant change in extracellular space at 16 days gestation, 3% was occupied by extracellular space. Each volume ratio was found to be nearly constant throughout the studied period. In contrast to this constancy in the volume ratios, other parameters which were measured demonstrated significant changes during the developmental period studied. These overall changes include a 135% increase in capillary density, a 63% increase in luminal surface area of capillary endothelial cells, a 24% decrease in capillary diameter, a 12% decrease in diffusion distance, and a 35% decrease in the diameter of the erythrocyte population.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:3618523

Porter, G A; Bankston, P W

1987-06-01

178

Quantitative analysis of regional myocardial performance in coronary artery disease  

NASA Technical Reports Server (NTRS)

Findings from a group of subjects with significant coronary artery stenosis are given. A group of controls determined by use of a quantitative method for the study of regional myocardial performance based on the frame-by-frame analysis of biplane left ventricular angiograms are presented. Particular emphasis was placed upon the analysis of wall motion in terms of normalized segment dimensions, timing and velocity of contraction. The results were compared with the method of subjective assessment used clinically.

Stewart, D. K.; Dodge, H. T.; Frimer, M.

1975-01-01

179

Injectable myocardial matrix as a scaffold for myocardial tissue engineering  

Microsoft Academic Search

Current injectable materials utilized in myocardial tissue engineering have been borrowed from other tissue engineering applications and have not been specifically designed for the myocardium. We have recently tested the feasibility of using an injectable form of myocardial extracellular matrix that would provide cardiac specific matrix cues as well as be amenable to minimally invasive delivery. We have demonstrated that

Jennifer M. Singelyn; Jessica A. DeQuach; Karen L. Christman

2009-01-01

180

Insulin-like growth factor promotes engraftment, differentiation, and functional improvement after transfer of embryonic stem cells for myocardial restoration.  

PubMed

Insulin-like growth factor-1 (IGF-1) promotes myocyte proliferation and can reverse cardiac abnormalities when it is administered in the early fetal stage. Supplementation of a mouse embryonic stem cell (ESC) suspension with IGF-1 might enhance cellular engraftment and host organ-specific differentiation after injection in the area of acute myocardial injury. In the study reported here, we sought to enhance the restorative effect of ESCs in the injured heart by adding IGF-1 to the injected cell population. Green fluorescent protein (GFP)-labeled sv129 ESCs (2.5 x 10(5)) were injected into the ischemic area after left anterior descending (LAD) artery ligation in BalbC mice. Recombinant mouse IGF-1 (25 ng) was added to the cell suspension prior to the injection (n = 5). Echocardiography was performed before organ harvest 2 weeks later. The degree of restoration (ratio of GFP+ to infarct area), expression of cardiac markers by GFP+ cells, inflammatory response, and tumorigenicity were evaluated. Mice with LAD ligation only (n = 5) and ESC transfer without IGF-1 (n = 5) served as controls. ESCs formed viable grafts and improved cardiac function. Left ventricular wall thickness was higher in the IGF-1 group (p = .025). There was a trend toward higher fractional shortening in the IGF-treated group. Histological analysis demonstrated that IGF-1 promoted expression of alpha-sarcomeric actin (p = .015) and major histocompatibility complex class I (p = .01). IGF did not affect the cellular response to the donor cells or tumorigenicity. IGF-1 promotes expression of cardiomyocyte phenotype in ESCs in vivo. It should be considered as an adjuvant to cell transfer for myocardial restoration. PMID:15579642

Kofidis, Theo; de Bruin, Jorg L; Yamane, Toshiyuki; Balsam, Leora B; Lebl, Darren R; Swijnenburg, Rutger-Jan; Tanaka, Masashi; Weissman, Irving L; Robbins, Robert C

2004-01-01

181

Tissue-engineered pro-angiogenic fibroblast scaffold improves myocardial perfusion and function and limits ventricular remodeling after infarction  

PubMed Central

Objective Microvascular malperfusion after myocardial infarction leads to infarct expansion, adverse remodeling, and functional impairment. Native reparative mechanisms exist but are inadequate to vascularize ischemic myocardium. We hypothesized that a 3-dimensional human fibroblast culture (3DFC) functions as a sustained source of angiogenic cytokines, thereby augmenting native angiogenesis and limiting adverse effects of myocardial ischemia. Methods Lewis rats underwent ligation of the left anterior descending coronary artery to induce heart failure; experimental animals received a 3DFC scaffold to the ischemic region. Border-zone tissue was analyzed for the presence of human fibroblast surface protein, vascular endothelial growth factor, and hepatocyte growth factor. Cardiac function was assessed with echocardiography and pressure–volume conductance. Hearts underwent immunohistochemical analysis of angiogenesis by co-localization of platelet endothelial cell adhesion molecule and alpha smooth muscle actin and by digital analysis of ventricular geometry. Microvascular angiography was performed with fluorescein-labeled lectin to assess perfusion. Results Immunoblotting confirmed the presence of human fibroblast surface protein in rats receiving 3DFC, indicating survival of transplanted cells. Increased expression of vascular endothelial growth factor and hepatocyte growth factor in experimental rats confirmed elution by the 3DFC. Microvasculature expressing platelet endothelial cell adhesion molecule/alpha smooth muscle actin was increased in infarct and border-zone regions of rats receiving 3DFC. Microvascular perfusion was also improved in infarct and border-zone regions in these rats. Rats receiving 3DFC had increased wall thickness, smaller infarct area, and smaller infarct fraction. Echocardiography and pressure–volume measurements showed that cardiac function was preserved in these rats. Conclusions Application of a bioengineered 3DFC augments native angiogenesis through delivery of angiogenic cytokines to ischemic myocardium. This yields improved microvascular perfusion, limits infarct progression and adverse remodeling, and improves ventricular function. PMID:20363480

Fitzpatrick, J. Raymond; Frederick, John R.; McCormick, Ryan C.; Harris, David A.; Kim, Ah-Young; Muenzer, Jeffrey R.; Gambogi, Alex J.; Liu, Jing Ping; Paulson, E. Carter; Woo, Y. Joseph

2011-01-01

182

Follow-up after polypropylene mesh repair of anterior and posterior compartments in patients with recurrent prolapse  

Microsoft Academic Search

To retrospectively analyze the outcome of surgery in women followed up for 1 year after vaginal repair with the Apogee? (support\\u000a of posterior vaginal wall) or Perigee? (support of anterior vaginal wall) system. A total of 120 patients with recurrent cystocele\\u000a and\\/or rectocele or with combined vaginal vault prolapse were treated by either posterior or anterior mesh interposition depending\\u000a on the

A. Gauruder-Burmester; P. Koutouzidou; J. Rohne; M. Gronewold; R. Tunn

2007-01-01

183

Biomarkers in acute myocardial infarction  

Microsoft Academic Search

Myocardial infarction causes significant mortality and morbidity. Timely diagnosis allows clinicians to risk stratify their patients and select appropriate treatment. Biomarkers have been used to assist with timely diagnosis, while an increasing number of novel markers have been identified to predict outcome following an acute myocardial infarction or acute coronary syndrome. This may facilitate tailoring of appropriate therapy to high-risk

Daniel Chan; Leong L Ng

2010-01-01

184

Dipyridamole thallium-201 myocardial scintigraphy  

SciTech Connect

Thallium-201 (/sup 201/Tl) myocardial scintigraphy is a sensitive technique for detecting coronary artery disease. Standardized exercise testing is the most common method for inducing myocardial stress for /sup 201/Tl imaging. Unfortunately, a significant number of patients are unable to undergo adequate treadmill or bicycle exercise. In these patients, pharmacologic stress with dipyridamole provides a safe, efficacious, and reliable alternative.

Not Available

1988-09-01

185

Periostin as a modulator of chronic cardiac remodeling after myocardial infarction  

PubMed Central

OBJECTIVE: After acute myocardial infarction, during the cardiac repair phase, periostin is released into the infarct and activates signaling pathways that are essential for the reparative process. However, the role of periostin in chronic cardiac remodeling after myocardial infarction remains to be elucidated. Therefore, the objective of this study was to investigate the relationship between tissue periostin and cardiac variables in the chronic cardiac remodeling induced by myocardial infarction. METHODS: Male Wistar rats were assigned to 2 groups: a simulated surgery group (SHAM; n?=?8) and a myocardial infarction group (myocardial infarction; n?=?13). After 3 months, morphological, functional and biochemical analyses were performed. The data are expressed as means±SD or medians (including the lower and upper quartiles). RESULTS: Myocardial infarctions induced increased left ventricular diastolic and systolic areas associated with a decreased fractional area change and a posterior wall shortening velocity. With regard to the extracellular matrix variables, the myocardial infarction group presented with higher values of periostin and types I and III collagen and higher interstitial collagen volume fractions and myocardial hydroxyproline concentrations. In addition, periostin was positively correlated with type III collagen levels (r?=?0.673, p?=?0.029) and diastolic (r?=?0.678, p?=?0.036) and systolic (r?=?0.795, p?=?0.006) left ventricular areas. Considering the relationship between periostin and the cardiac function variables, periostin was inversely correlated with both the fractional area change (r?=?-0.783, p?=?0.008) and the posterior wall shortening velocity (r?=?-0.767, p?=?0.012). CONCLUSIONS: Periostin might be a modulator of deleterious cardiac remodeling in the chronic phase after myocardial infarction in rats. PMID:24212842

Minicucci, Marcos F.; dos Santos, Priscila P.; Rafacho, Bruna P. M.; Goncalves, Andrea F.; Ardisson, Lidiane P.; Batista, Diego F.; Azevedo, Paula S.; Polegato, Bertha F.; Okoshi, Katashi; Pereira, Elenize J.; Paiva, Sergio A. R.; Zornoff, Leonardo A. M.

2013-01-01

186

Wonderful Walls  

ERIC Educational Resources Information Center

In this article, the author emphasizes the importance of "working" walls in children's programs. Children's programs need "working" walls (and ceilings and floors) which can be put to use for communication, display, storage, and activity space. The furnishings also work, or don't work, for the program in another sense: in aggregate, they serve as…

Greenman, Jim

2006-01-01

187

Cause of Chest Pain in a Patient with Previous Myocardial Infarction: Look Outside the Heart for Extracardiac Mass  

PubMed Central

We report a case of thymic carcinoma that was initially detected by echocardiography in an 80-year-old male who visited the emergency room for chest pain and had a history of myocardial infarction and percutaneous coronary intervention. Transthoracic echocardiography showed a huge extracardiac mass that was located in the anterior mediastinum and was diagnosed as a thymic carcinoma by biopsy. PMID:22247920

Lee, Dae In; Kim, Su A; Kang, Jun Hyuk; Lee, Jae Hyoung; Park, Sang Jung; Yoon, Dae Woong; Shim, Wan-Joo

2011-01-01

188

Identifying Early Changes in Myocardial Microstructure in Hypertensive Heart Disease  

PubMed Central

The transition from healthy myocardium to hypertensive heart disease is characterized by a series of poorly understood changes in myocardial tissue microstructure. Incremental alterations in the orientation and integrity of myocardial fibers can be assessed using advanced ultrasonic image analysis. We used a modified algorithm to investigate left ventricular myocardial microstructure based on analysis of the reflection intensity at the myocardial-pericardial interface on B-mode echocardiographic images. We evaluated the extent to which the novel algorithm can differentiate between normal myocardium and hypertensive heart disease in humans as well as in a mouse model of afterload resistance. The algorithm significantly differentiated between individuals with uncomplicated essential hypertension (N?=?30) and healthy controls (N?=?28), even after adjusting for age and sex (P?=?0.025). There was a trend in higher relative wall thickness in hypertensive individuals compared to controls (P?=?0.08), but no difference between groups in left ventricular mass (P?=?0.98) or total wall thickness (P?=?0.37). In mice, algorithm measurements (P?=?0.026) compared with left ventricular mass (P?=?0.053) more clearly differentiated between animal groups that underwent fixed aortic banding, temporary aortic banding, or sham procedure, on echocardiography at 7 weeks after surgery. Based on sonographic signal intensity analysis, a novel imaging algorithm provides an accessible, non-invasive measure that appears to differentiate normal left ventricular microstructure from myocardium exposed to chronic afterload stress. The algorithm may represent a particularly sensitive measure of the myocardial changes that occur early in the course of disease progression. PMID:24831515

Hiremath, Pranoti; Bauer, Michael; Aguirre, Aaron D.; Cheng, Hui-Wen; Unno, Kazumasa; Patel, Ravi B.; Harvey, Bethany W.; Chang, Wei-Ting; Groarke, John D.; Liao, Ronglih; Cheng, Susan

2014-01-01

189

Diffuse anterior retinoblastoma: A review?  

PubMed Central

Diffuse anterior retinoblastoma is a rare variant of diffuse infiltrating retinoblastoma which occurs in up to 1–2% of cases of retinoblastoma. In diffuse anterior retinoblastoma there is a small focus of tumor in the peripheral retina from which free tumor cells enter the aqueous humor and implant on the ciliary body, iris, lens and trabecular meshwork. Patients most commonly present with pseudouveitis, pseudohypopyon and increased intraocular pressure. The differential diagnosis is broad and all of the reported cases relied upon aspirates from the aqueous humor in order to make the diagnosis prior to proceeding with treatment. Treatment involves enucleation and, depending upon the extent of the tumor, may require systemic chemotherapy or external beam radiation. This review summarizes the 7 previously reported cases of diffuse anterior retinoblastoma, discusses pathologic features, and addresses the challenges of early diagnosis and future directions. PMID:24227977

Jijelava, Kristen P.; Grossniklaus, Hans E.

2013-01-01

190

Left ventricular myocardial blood flow in multivessel coronary artery disease.  

PubMed

The relationship between resting left ventricular (LV) myocardial blood flow (MBF) and hemodynamic determinants of myocardial oxygen consumption was investigated in 15 patients with multivessel coronary artery disease (CAD) and in 10 patients with normal coronary arteriograms. Mean LV MBF per unit mass of tissue was measured with a multicrystal scintillation camera from the regional clearance rates of xenon-133 injected into the left main coronary artery. Peak LV wall stress, mean velocity of circumferential fiber shortening (Vcf), rate of ejection during the first third of systole (1/3 SV), LV ejection fraction (EF), and the ratio of peak LV systolic pressure to LV end-systolic volume were measured by contrast left ventriculography. Mean LV MBF per unit mass was significantly reduced (48 +/- 11 vs 67 +/- 12 ml/100 g.min; p less than 0.01) in patients with multivessel CAD. However, none of the patients with CAD experienced chest pain or had electrocardiographic evidence of myocardial ischemia during the resting MBF measurements. Ejection phase indexes were lower in the patients with CAD: LVEF (56 +/- 10% vs 64 +/- 7%, p less than 0.05); 1/3 SV (35 +/- 3 vs 44 +/- 4%, p less than 0.05); and mean Vcf (1.05 +/- 0.30 vs 1.19 +/- 0.27 circ/sec, NS). LV wall thickness (9.8 +/- 1.9 vs 7.5 +/- 1.4 mm, p less than 0.01) and LV mass index (94 +/- 32 vs 64 +/- 17 g/m2, p less than 0.05) were significantly increased in the patients with CAD, accounting for the reduction in peak LV wall stress (276 +/- 73 vs 373 +/- 91 dyn-cm-2 x 10(-3), p less than 0.05) observed in these patients. Multiple regression analysis indicated that indexes of three of the major determinants of myocardial oxygen consumption explained 65% of the variation in MBF in patients with CAD: peak LV stress, mean Vcf and heart rate. After adjustment for these three indexes, the average LV MBF rates were not significantly different in the two patient groups (54.8 +/- 1.8 vs 57.6 +/- 2.3 ml/100 g.min). In both groups, resting LV MBF/beat correlated most highly with peak LV wall stress (r = 0.79). Thus, the reduction in LV MBF per unit mass observed in patients with multivessel CAD at rest is related to lower levels of hemodynamic variables that determine myocardial oxygen consumption. Peak LV wall stress is the most important hemodynamic variable determining the level of resting MBF in patients with and without CAD. PMID:7094265

Chen, P H; Nichols, A B; Weiss, M B; Sciacca, R R; Walter, P D; Cannon, P J

1982-09-01

191

Ventricular myocardial architecture in marine fishes.  

PubMed

The fiber architecture of the ventricular myocardium has been studied in elasmobranch (Isurus oxyrhinchus, Galeorhinus galeus, Prionace glauca) and teleost (Xiphias gladius, Thunnus thynnus, Thunnus alalunga) fish species with hearts displaying mixed types of ventricular musculature (compact and trabecular). In all cases, the compact myocardium is organized in layers of fiber bundles with an orderly arrangement within the ventricular walls. The number of these layers appears to be dependent on the relative thickness of the compact myocardium. Differences in the pattern of myocardial fiber arrangement were observed among the different fish species. In elasmobranchs the compact myocardium at the level of the atrioventricular orifice is continuous with the trabeculated myocardium. Furthermore, in elasmobranchs the trabeculated myocardium displays a precise arrangement in arcuate trabeculae running from the auriculoventricular to the conoventricular orifices. In teleosts, the compact myocardium is independent of the trabeculated myocardium and a large number of fibers insert into the bulboventricular fibrous ring. The trabeculated myocardium in these species displays an anarchic arrangement except at the level of the bulboventricular orifice, where the fibers tend to be aligned longitudinally, also being inserted into the fibrous ring. Minor differences, consisting mainly of the presence of extra bundles of fibers, were also observed among different individuals of the same species. The possible relationship between myocardial fiber architecture and ventricular shape is discussed. PMID:3578842

Sanchez-Quintana, D; Hurle, J M

1987-03-01

192

Reversible abnormalities of myocardial relaxation in hypothyroidism.  

PubMed

Fifteen selected hypothyroid patients without symptoms or signs of cardiovascular disease and an equal number of matched control subjects underwent simultaneous recording of electrocardiogram and phono-, apex-, and echocardiography to assess dynamic systolic and diastolic left ventricular function. Both the systolic preejection period and the isovolumic relaxation period were significantly increased in the hypothyroid group. However, whereas the rate of myocardial contraction, assessed from the echocardiograph of the left ventricular posterior wall, was identical in patients and control subjects, the diastolic thinning rate of the muscle was markedly slowed in the hypothyroid individuals. The abnormalities demonstrated were in the main completely reversed after 3 months of T4 therapy. These results demonstrate a relatively selective and readily reversible disturbance of the rate of myocardial relaxation in hypothyroidism, suggesting an intrinsic abnormality of cardiac muscle. This allows an intriguing parallel to be drawn with the delayed relaxation phase of voluntary muscle contraction, long recognized as a direct measure of tissue thyroid function in hypothyroidism. The abnormality of diastolic function we have described is of similar character to that found in patients with other cardiomyopathies and which has been shown to be a major cause of disturbance of global cardiac action. PMID:4008607

Vora, J; O'Malley, B P; Petersen, S; McCullough, A; Rosenthal, F D; Barnett, D B

1985-08-01

193

Arthroscopic Augmentation With Subscapularis Tendon in Anterior Shoulder Instability With Capsulolabral Deficiency  

PubMed Central

The treatment of chronic shoulder instability with poor quality of the anterior capsulolabral tissue is still controversial. In these cases the Latarjet procedure is certainly more effective in preventing recurrence than an arthroscopic capsular repair. However, several studies have reported a variety of severe complications related to the Latarjet procedure because of the use of bone augmentation and hardware implantation; moreover, the arthroscopic version of the Latarjet procedure is technically difficult and potentially dangerous because of the proximity of neurovascular structures. The aim of this report is to describe an innovative arthroscopic technique consisting of an augmentation of the anterior capsulolabral tissue using the articular portion of the subscapularis tendon and knotless suture anchors paired with high-strength tape for its fixation to the anterior glenoid edge. In the absence of severe bone deficiency of the anterior glenoid edge, this procedure can minimize arthroscopic technique failures, restoring the anterior capsulolabral wall without any significant reduction of shoulder functionality. PMID:24266004

Maiotti, Marco; Massoni, Carlo

2013-01-01

194

Loss of dystrophin staining in cardiomyocytes: a novel method for detection early myocardial infarction  

PubMed Central

Myocardial infarction (MI) is the most frequent diagnosis made in majority of sudden death cases subjected to clinical and medicolegal autopsies. When sudden death occurs at a very early stage of MI, traditional macroscopic examination, or histological stains cannot easily detect the myocardial changes. For this reason we propose a new method for detecting MI at an early stage. Murine model of MI was used to induce MI through permanent ligation of left anterior descending branch of left coronary artery. Five groups of C57B6/J mice were used for inducing MI, which includes 20 minutes, 30 minutes, one hour, four hours and 24 hours post MI groups. One naïve group and sham-operated groups were used as controls. There is loss of dystrophin membranous staining in cardiac myocytes occurs as early as 20 minutes post myocardial infarction. This can be used as a novel method to diagnose early myocardial infarction in post mortem cases where diagnosis is unclear. In conclusion, evaluation of immunohistochemical expression of dystrophin represents a highly sensitive method for detecting early myocardial infarction due to the loss of staining in the infarcted areas. Dystrophin immunostaining can also be used to assess myocardial architecture. PMID:23330010

Hashmi, Satwat; Al-Salam, Suhail

2013-01-01

195

(1) Coronary Events Caused by Myocardial Bridge  

PubMed Central

Myocardial bridge (MB), which covers a part of the left anterior descending coronary artery (LAD), is a normal anatomical variant structure (45% in frequency by autopsy) in LAD. MB contraction plays the role of a “double-edged sword” on the coronary events, suppressing coronary atherosclerosis under the MB, yet generating abnormal blood flow associated with coronary heart diseases (CHDs). High shear stress driven by MB compression causes the suppression of vascular permeability and vasoactive protein expression such as e-NOS and endothelin-1, which leads to the suppression of atherosclerosis in the LAD segment under the MB. However, despite the prevalent view of MB as benignancy by conventional coronary angiography (5-6% in frequency), with advance of imaging technique such as multislice spiral computed tomography [(MSCT); 16% in frequency], cardiologists are now frequently aware of symptomatic MB occurring not only in hospitalized patients, but also in young athletes free from atherosclerosis. Moreover, the large mass volume of MB muscle induces atherosclerosis evolution at the settled site in LAD proximal to MB and contributes to the occurrence of myocardial infarction. These events upon the coronary events result from the different pathophysiological mechanisms induced by contractile force of MB, which is solely determined just by the integration of anatomical properties of MB, such as the location, length and thickness of MB in an individual LAD. A recent MSCT provides the objective quantification of the anatomical variables that correlate with the histopathological results in relation to the occurrence of CHD. In this review, we therefore discuss the necessity to explore MB as a inherent chance anatomical risk factor for CHD. PMID:23555365

Yoko, Kawawa; Ehiichi, Kohda; Toshiharu, Ishii

2009-01-01

196

Myocardial infarction after taking eletriptan.  

PubMed

We report the case of a 53-year-old male patient with a medical history significant for paroxysmal atrial fibrillation, migraines with visual aura and non-obstructive coronary artery disease, who sustained a non-ST-elevation myocardial infarction a few hours after taking eletriptan as abortive therapy for migraine headaches. We believe this case implies a causal association between eletriptan and myocardial infarction, considering the timing of both drug intake and symptom onset. To the best of our knowledge this is the first reported myocardial infarction attributable to eletriptan overdose in a patient without obstructive coronary artery disease. PMID:25155004

Dias, Andre; Franco, Emiliana; Hebert, Kathy; Mercedes, Ana

2014-01-01

197

The Anterior and Midcingulate Cortices  

E-print Network

Pleasant versus unpleasant olfactory stimuli 194 The reward value of food 195 The reward value of water 195 cingulate activity that codes the reward value for food and water. 4 Present links between cognitiveCHAPTER 8 The Anterior and Midcingulate Cortices and Reward Edmund T. Rolls Chapter contents Goals

Rolls, Edmund T.

198

NADH in situ laser fluorimetry: effect of pentobarbital on continuously monitored myocardial redox state  

SciTech Connect

NADH laser fluorimetry was applied to in situ monitoring of pentobarbital overload effect on myocardial redox state in rats. Experiments were carried out on open-chest rats anesthetized with pentobarbital. Use of very thin optical probes allowed measurements of NADH fluorescence directly within the myocardial wall. Quantitative analysis of fluorescent and backscattered light signals was made possible on-line. In 8 animals, a slow IV infusion of 6% pentobarbital (2 mg.min-1 for 10 min) induced an average twofold increase in NADH fluorescence, with constant return to baseline level prior to injection after a maximum period of 50 min. Thus, pentobarbital overload strongly affects the myocardial energetic state, and this effect was precisely evaluated with NADH fluorescence monitoring. In situ-monitored myocardial redox state variations during pentobarbital infusion can constitute a reference for similar studies on pharmacological agents aimed at protecting tissues against ischemic biochemical damages.

Renault, G.; Muffat-Joly, M.; Polianski, J.; Hardy, R.I.; Boutineau, J.L.; Duvent, J.L.; Pocidalo, J.J.

1987-01-01

199

Global and regional left ventricular ejection fraction abnormalities during exercise in patients with silent myocardial ischemia  

SciTech Connect

Sixteen asymptomatic patients with coronary artery disease and silent myocardial ischemia were studied with exercise radionuclide ventriculography. Radionuclide ventriculograms were analyzed for changes in ejection fraction globally and in three regions. Results were compared with radionuclide ventriculograms in 24 symptomatic patients. Both groups (silent myocardial ischemia and angina) were similar in prevalence of multivessel disease and previous myocardial infarction, as well as in age and sex. Global ejection fraction decreased by 0.06 in both groups during exercise; regional ejection fraction also decreased by similar amounts in the two groups. Furthermore, the percent of regions with normal ejection fraction at rest that demonstrated a decrease during exercise was identical: 19 (60%) of 33 versus 26 (60%) of 46. These exercise radionuclide ventriculographic results suggest that abnormalities in regional and global left ventricular wall motion are similar in patients with coronary artery disease with and without silent myocardial ischemia.

Cohn, P.F.; Brown, E.J. Jr.; Wynne, J.; Holman, B.L.; Atkins, H.L.

1983-03-01

200

Beneficial role of tamoxifen in isoproterenol-induced myocardial infarction.  

PubMed

ER-? and ER-? agonist 17?-estradiol is reported to attenuate cardiac hypertrophy. Tamoxifen is a selective estrogen receptor modulator. Hence, the objective of this study was to investigate the effects of tamoxifen in myocardial infarction. For this, tamoxifen was administered to Sprague-Dawley rats for 1-14 days, and isoproterenol (ISO) (100 mg·(kg body mass)(-1)·day(-1)) was administered subcutaneously on the 13th and 14th days of the study in order to induce myocardial infarction, after which, various biochemical, cardiac, and morphometric parameters were evaluated. ISO produced significant dyslipidemia, hypertension, bradycardia, oxidative stress, and an increase in serum cardiac markers. Treatment with tamoxifen significantly controlled dyslipidemia, hypertension, bradycardia, oxidative stress, and reduced serum cardiac markers. The ISO control rats exhibited significant increases in the infarct size of the left ventricle (LV), LV cavity area, cardiac and LV hypertrophic indices, LV-wall thickness, cardiomyocyte diameter, and area. Treatment with tamoxifen significantly reduced infarction as well as hypertrophic and morphometric parameters. ISO also produced significant increases in the LV collagen level, decreases in Na(+)K(+) ATPase activity, and a reduction in the rate of pressure development and decay, which were prevented by tamoxifen treatment. The protective effect of tamoxifen on myocardial infarct was further confirmed by histopathological examination. Our data thus suggest that tamoxifen exerts beneficial effects in ISO-induced myocardial infarction. PMID:25243890

Rayabarapu, Nihar; Patel, Bhoomika M

2014-10-01

201

Myocardial contractile function in survived neonatal piglets after cardiopulmonary bypass  

PubMed Central

Background Hemodynamic function may be depressed in the early postoperative stages after cardiac surgery. The aim of this study was the analysis of the myocardial contractility in neonates after cardiopulmonary bypass (CPB) and mild hypothermia. Methods Three indices of left ventricular myocardial contractile function (dP/dt, (dP/dt)/P, and wall thickening) were studied up to 6 hours after CPB in neonatal piglets (CPB group; n = 4). The contractility data were analysed and then compared to the data of newborn piglets who also underwent median thoracotomy and instrumentation for the same time intervals but without CPB (non-CPB group; n = 3). Results Left ventricular dP/dtmax and (dP/dtmax)/P remained stable in CPB group, while dP/dtmax decreased in non-CPB group 5 hours postoperatively (1761 ± 205 mmHg/s at baseline vs. 1170 ± 205 mmHg/s after 5 h; p < 0.05). However, with regard to dP/dtmax and (dP/dtmax)/P there were no statistically significant differences between the two groups. Comparably, although myocardial thickening decreased in the non-CPB group the differences between the two groups were not statistically significant. Conclusions The myocardial contractile function in survived neonatal piglets remained stable 6 hours after cardiopulmonary bypass and mild hypothermia probably due to regional hypercontractility. PMID:21044329

2010-01-01

202

Masquerades of myocardial infarction.  

PubMed Central

I summarize these observations in Figure 1. It represents every person in a hypothetical population who has myocardial infarction. A large but unknown number, some believe almost half, never get help. Mobile coronary care units are reducing this group, but so far only a little. When the diagnosis is not understood the disease is not recognized. Then come discovery and popularization. Hereafter masquerades hide some cases and the diagnosis is missed. Somewhere fairly early the diagnostic fad leads to false positive diagnosis. As new techniques are discovered, perfected and mastered, false positive errors and masquerades leading to oversights diminish but still exist. All the skill and technical virtuosity in the world will not be applied if we do not think of the disease. When we think of it, even obscure cases may be resolved easily. PMID:960416

Bean, W. B.

1976-01-01

203

Altered phosphate metabolism in myocardial infarction: P-31 MR spectroscopy  

SciTech Connect

The high-energy myocardial phosphate metabolism of four patients with acute anterior myocardial infarction after coronary angioplasty and drug therapy was evaluated with cardiac-gated phosphorus magnetic resonance (MR) depth-resolved surface coil spectroscopy (DRESS) 5-9 days after the onset of symptoms. Significant reductions (about threefold) in the phosphocreatine (PCr) to inorganic phosphate (Pi) ratio and elevations in the Pi to adenosine triphosphate (ATP) ratio were observed in endocardially or transmurally derived MR spectra when compared with values from epicardially displaced spectra and values from seven healthy volunteers (P less than .05). High-energy phosphate metabolites and Pi ratios did not vary significantly during the cardiac cycle in healthy volunteers. However, contamination of Pi resonances by phosphomonoester components, including blood 2,3-diphosphoglycerate, precluded accurate spectral quantification of Pi and pH. The results indicate that localized P-31 MR spectroscopy may be used to directly assess cellular energy reserve in clinical myocardial infarction and to evaluate metabolic response to interventions.

Bottomley, P.A.; Herfkens, R.J.; Smith, L.S.; Bashore, T.M.

1987-12-01

204

Exercise training prior to myocardial infarction attenuates cardiac deterioration and cardiomyocyte dysfunction in rats  

PubMed Central

OBJECTIVES: The present study was performed to investigate 1) whether aerobic exercise training prior to myocardial infarction would prevent cardiac dysfunction and structural deterioration and 2) whether the potential cardiac benefits of aerobic exercise training would be associated with preserved morphological and contractile properties of cardiomyocytes in post-infarct remodeled myocardium. METHODS: Male Wistar rats underwent an aerobic exercise training protocol for eight weeks. The rats were then assigned to sham surgery (SHAM), sedentary lifestyle and myocardial infarction or exercise training and myocardial infarction groups and were evaluated 15 days after the surgery. Left ventricular tissue was analyzed histologically, and the contractile function of isolated myocytes was measured. Student's t-test was used to analyze infarct size and ventricular wall thickness, and the other parameters were analyzed by the Kruskal-Wallis test followed by Dunn's test or a one-way analysis of variance followed by Tukey's test (p<0.05). RESULTS: Myocardial infarctions in exercise-trained animals resulted in a smaller myocardial infarction extension, a thicker infarcted wall and less collagen accumulation as compared to myocardial infarctions in sedentary animals. Myocardial infarction-induced left ventricular dilation and cardiac dysfunction, as evaluated by +dP/dt and -dP/dt, were both prevented by previous aerobic exercise training. Moreover, aerobic exercise training preserved cardiac myocyte shortening, improved the maximum shortening and relengthening velocities in infarcted hearts and enhanced responsiveness to calcium. CONCLUSION: Previous aerobic exercise training attenuated the cardiac dysfunction and structural deterioration promoted by myocardial infarction, and such benefits were associated with preserved cardiomyocyte morphological and contractile properties. PMID:23778353

Bozi, Luiz Henrique Marchesi; dos Santos Costa Maldonado, Izabel Regina; Baldo, Marcelo Perim; da Silva, Marcia Ferreira; Moreira, Jose Bianco Nascimento; Novaes, Romulo Dias; Ramos, Regiane Maria Soares; Mill, Jose Geraldo; Brum, Patricia Chakur; Felix, Leonardo Bonato; Gomes, Thales Nicolau Primola; Natali, Antonio Jose

2013-01-01

205

Mini-open anterior spine surgery for anterior lumbar diseases  

Microsoft Academic Search

Minimally invasive surgeries including endoscopic surgery and mini-open surgery are current trend of spine surgery, and its\\u000a main advantages are shorter recovery time and cosmetic benefits, etc. However, mini-open surgery is easier and less technique\\u000a demanding than endoscopic surgery. Besides, anterior spinal fusion is better than posterior spinal fusion while considering\\u000a the physiological loading, back muscle function, etc. Therefore, we

Ruey-Mo Lin; Kuo-Yuan Huang; Kuo-An Lai

2008-01-01

206

Inhibition of histone deacetylase-induced myocardial repair is mediated by c-kit in infarcted hearts.  

PubMed

Histone deacetylases (HDACs) play a critical role in the regulation of gene transcription, cardiac development, and diseases. The aim of this study was to test whether inhibition of HDACs induces myocardial repair and cardiac function restoration through c-kit signaling in mouse myocardial infarction models. Myocardial infarction in wild type Kit(+/+) and Kit(W)/Kit(W-v) mice was created following thoracotomy by applying permanent ligation to the left anterior descending artery. The HDAC inhibitor, trichostatin A (TSA, 0.1 mg/kg), was intraperitoneally injected daily for a consecutive 8 weeks after myocardial infarction. 5-Bromo-2-deoxyuridine (BrdU, 50 mg/kg) was intraperitoneally delivered every other day to pulse-chase label in vivo endogenous cardiac replication. Eight weeks later, inhibition of HDACs in vivo resulted in an improvement in ventricular functional recovery and the prevention of myocardial remodeling in Kit(+/+) mice, which was eliminated in Kit(W)/Kit(W-v) mice. HDAC inhibition promoted cardiac repairs and neovascularization in the infarcted myocardium, which were absent in Kit(W)/Kit(W-v) mice. Re-introduction of TSA-treated wild type c-kit(+) CSCs into Kit(W)/Kit(W-v) myocardial infarction heart restored myocardial functional improvement and cardiac repair. To further validate that HDAC inhibition stimulates c-kit(+) cardiac stem cells (CSCs) to facilitate myocardial repair, GFP(+) c-kit(+) CSCs were preconditioned with TSA (50 nmol/liter) for 24 h and re-introduced into infarcted hearts for 2 weeks. Preconditioning of c-kit(+) CSCs via HDAC inhibition with trichostatin A significantly increased c-kit(+) CSC-derived myocytes and microvessels and enhanced functional recovery in myocardial infarction hearts in vivo. Our results provide evidence that HDAC inhibition promotes myocardial repair and prevents cardiac remodeling, which is dependent upon c-kit signaling. PMID:23024362

Zhang, Ling; Chen, Bing; Zhao, Yu; Dubielecka, Patrycja M; Wei, Lei; Qin, Gang J; Chin, Y Eugene; Wang, Yigang; Zhao, Ting C

2012-11-16

207

Refined ambient PM2.5 exposure surrogates and the risk of myocardial infarction  

EPA Science Inventory

Using a case-crossover study design and conditional logistic regression, we compared the relative odds of transmural (full-wall) myocardial infarction (MI) calculated using exposure surrogates that account for human activity patterns and the indoor transport of ambient PM2....

208

Successful infarct exclusion for postinfarction left ventricular free wall rupture  

PubMed Central

The mortality of postinfarction left ventricular free wall rupture is still high. Several surgical techniques have been used for repairing such ruptures. Here, we describe using an infarction exclusion technique to successfully treat a case of a blow-out type postinfarction left ventricular free wall rupture. This technique has frequently been used for repairing postinfarction ventricular septal perforation. In this case, infarcted myocardial tearing was prevented, and complete haemostasis was achieved by infarct exclusion. PMID:23424241

Kato, Yasuyuki; Fukui, Toshihiro; Tabata, Minoru; Takanashi, Shuichiro

2013-01-01

209

A heart with multiple coronaries anomalies: myocardial bridging, left dominance and high takeoff of ostia-an autopsy case.  

PubMed

Myocardial bridging is a segment of coronary artery that runs intramurally through the myocardium. Though it is commonly seen in the anterior interventricular artery and less commonly in right coronary artery, it can cause limitation in the blood flow, which leads to myocardial ischaemia. Left dominance increases cardiac mortality because of association with the congenital bicuspid aortic valve and myocardial infarction. An earlier study has shown the correlation of myocardial bridging with left coronary circulation and it is rare in relation with right coronary and left dominance. Manifestations of high takeoff of the coronary ostia are highly debatable, with varied opinions given by various authors. It has been believed that myocardial bridging is congenital and that it also causes limitation of blood flow to the myocardium. Cardiac muscles have a unique capability to adapt in response to decreased blood supply, which is in the form of coronary collateral circulation. So, is their any correlation between myocardial bridging and dominance? Herein, we are reporting an unusual autopsy case of myocardial bridging on its right main coronary artery, left coronary dominance and high take off of left main coronary artery in the same heart. PMID:24701509

Haswani, Lokesh; M L, Harendra Kumar; Kiran, J

2014-02-01

210

A Heart with Multiple Coronaries Anomalies: Myocardial Bridging, Left Dominance and High Takeoff of Ostia-An Autopsy Case  

PubMed Central

Myocardial bridging is a segment of coronary artery that runs intramurally through the myocardium. Though it is commonly seen in the anterior interventricular artery and less commonly in right coronary artery, it can cause limitation in the blood flow, which leads to myocardial ischaemia. Left dominance increases cardiac mortality because of association with the congenital bicuspid aortic valve and myocardial infarction. An earlier study has shown the correlation of myocardial bridging with left coronary circulation and it is rare in relation with right coronary and left dominance. Manifestations of high takeoff of the coronary ostia are highly debatable, with varied opinions given by various authors. It has been believed that myocardial bridging is congenital and that it also causes limitation of blood flow to the myocardium. Cardiac muscles have a unique capability to adapt in response to decreased blood supply, which is in the form of coronary collateral circulation. So, is their any correlation between myocardial bridging and dominance? Herein, we are reporting an unusual autopsy case of myocardial bridging on its right main coronary artery, left coronary dominance and high take off of left main coronary artery in the same heart. PMID:24701509

Haswani, Lokesh; M.L, Harendra Kumar; Kiran, J

2014-01-01

211

Revision open anterior approaches for spine procedures  

Microsoft Academic Search

Background contextAnterior exposure has become an increasingly popular procedure for the general and vascular surgeon due to the increased use of anterior lumbar interbody fusion and artificial disc replacement for the treatment of many spinal problems.

Andrew A. Gumbs; Scott Hanan; James J. Yue; Rahul V. Shah; Bauer Sumpio

2007-01-01

212

Potential and limitations of Tc-99m sestamibi scintigraphy for the diagnosis of myocardial viability.  

PubMed

Sestamibi is a Tc labeled radiotracer particularly suitable for myocardial perfusion studies, providing similar information as thallium scintigraphy for the diagnosis of coronary artery disease. In comparison with thallium, sestamibi has the advantage of improved imaging properties due to its higher gamma emission. This is particularly relevant when SPECT imaging is considered. The myocardial uptake of sestamibi is partially passively, related to the myocardial flow, and is also related to the metabolic cellular activity, as it is proportional to the electrochemical gradient generated at cell membrane level. While the role for sestamibi in diagnosing coronary artery disease is well accepted, it is still controversial for the assessment of myocardial viability. Clinical studies reported by others and results from our own institution will be described both in the setting of a recent myocardial infarction (myocardial stunning) and of longstanding left ventricular dysfunction (hibernating myocardium). The results concordantly suggest that sestamibi underestimates myocardial viability, compared to the accepted standards of thallium (rest-redistribution or stress-reinjection protocols), 18-F FDG PET and also in the prediction of left ventricular functional recovery after revascularisation. However, the data available at present are very limited, particularly after revascularisation. Furthermore, according to new promising results, the role of sestamibi in the setting of myocardial viability has potential for improvement, if the injection at rest will be performed during nitrates. It is also foreseen that the combined use of sestamibi perfusion/wall motion scan (first pass and/or gated perfusion studies) and the development of new softwares for attenuation correction might improve the results in the setting of myocardial viability. PMID:8150411

Cornel, J H; Arnese, M; Forster, T; Postma-Tjoa, J; Reijs, A E; Fioretti, P M

1994-02-01

213

Insights into the pathophysiology of ST-elevation myocardial infarction.  

PubMed

Although an approximate 13 million individuals in the United States are known to have coronary artery disease (CAD), only a small percentage of them develop unstable CAD each year. About 500,000 to 1 million people present annually with an ST-elevation myocardial infarction (STEMI), some of whom had never been diagnosed with CAD. The known etiology of coronary occlusion is the disruption of the atherosclerotic plaque within the vascular wall, and vascular inflammation is thought to lead to this disruption. Since many patients with CAD never suffer an myocardial infarction, the question then becomes why does inflammation-induced plaque disruption occur in only some patients? The explanation may lie in differing genetic and phenotypic characteristics. A greater understanding of the pathophysiology and the identification of new genetic and inflammatory markers are slowly leading to new therapeutic interventions that promise to greatly reduce the morbidity and mortality associated with CAD within the foreseeable future. PMID:16777509

Brener, Sorin J

2006-06-01

214

Hadrian's Wall  

NSDL National Science Digital Library

Hadrian's Wall is an historical monument built by the Romans in Britain and spans more than 2,000 years of history. Standing as a "reminder of past glories of one of the world's greatest civilisations," the Wall is equipped with museums, forts, and events that bring Roman history to life. Designed by the World Heritage Site, this Web site offers tourist information (such as travel and hotel arrangements) for anyone interested in visiting this historical landmark that ranks along with the great wonders of the world.

1998-01-01

215

Pediatric anterior cruciate ligament reconstruction  

Microsoft Academic Search

An increasing number of anterior cruciate ligament (ACL) injuries are seen in children now than in the past due to increased\\u000a sports participation. The natural history of ACL deficient knees in active individuals, particularly in children is poor.\\u000a Surgical management of ACL deficiency in children is complex due to the potential risk of injury to the physis and growth\\u000a disturbance.

Mark O. McConkey; Davide Edoardo Bonasia; Annunziato Amendola

2011-01-01

216

Localization of coronary artery disease with exercise electrocardiography: correlation with thallium-201 myocardial perfusion scanning  

SciTech Connect

In 61 patients with single vessel coronary artery disease (70 percent or greater obstruction of luminal diameter in only one vessel) and no previous myocardial infarction, the sites of ischemic changes on 12 lead exercise electrocardiography and on thallium-201 myocardial perfusion scanning were related to the obstructed coronary artery. The site of exercise-induced S-T segment depression did not identify which coronary artery was obstructed. In the 37 patients with left anterior descending coronary artery disease S-T depression was most often seen in the inferior leads and leads V4 to V6, and in the 18 patients with right coronary artery disease and in the 6 patients with left circumflex artery disease S-T depression was most often seen in leads V5 and V6. Although S-T segment elevation was uncommon in most leads, it occurred in lead V1 or a VL, or both, in 51 percent of the patients with left anterior descending coronary artery disease. A reversible anterior defect on exercise thallium scanning correlated with left anterior descending coronary artery disease (probability (p) less than 0.0001) and a reversible inferior thallium defect correlated with right coronary or left circumflex artery disease (p less than 0.0001). In patients with single vessel disease, the site of S-T segment depression does not identify the obstructed coronary artery; S-T segment elevation in lead V1 or aVL, or both, identifies left anterior descending coronary artery disease; and the site of reversible perfusion defect on thallium scanning identifies the site of myocardial ischemia and the obstructed coronary artery.

Dunn, R.F.; Freedman, B.; Bailey, I.K.; Uren, R.F.; Kelly, D.T.

1981-11-01

217

Die Arteria falcea anterior des Erwachsenen  

Microsoft Academic Search

The anterior falcate artery (arteria falcea anterior) represents the continuation of the anterior ethmoidal artery. In the adult, it has been described previously only in its rostral portion, which supplies the falx cerebri. In the present study, however, it is shown that there exists a continuation which runs in the parietal dura of the superior sagittal sinus and which unites

F. Müller

1978-01-01

218

Secondary anterior crocodile shagreen of Vogt  

Microsoft Academic Search

The clincopathological features and pathogenesis of secondary mosaic degeneration of the cornea (anterior crocodile shagreen of Vogt) are described. The structural basis for the normal anterior corneal mosaic pattern seems to lie in the particular arrangement of many prominent collagen lamellae of the anterior stroma that thake an oblique course to gain insertion into Bowman's layer. Since, at normal intraocular

R C Tripathi; A J Bron

1975-01-01

219

ANTERIOR KNEE PAIN RELATIONSHIP WITH Q ANGLE  

Microsoft Academic Search

Anterior knee pain one of the most friquent patient group for physician who deal with musculesceletal system. Presence of many reason of anterior knee pain ,leads many diffuculties in evaluation of this pain. Purpose of this study is to evaluate increase in Q angle whom is comman and contribution to anterior knee pain.50 patients with pain and 50 pain free

Atakan ÖZKAN; Devlet Hastanesi

220

Automatic implantable cardioverter/defibrillator discharges and acute myocardial injury  

SciTech Connect

Multiple defibrillations by the automatic implantable cardioverter/defibrillator (AICD) have been reported to result in localized epicardial damage. No data exist, however, regarding whether this damage can be detected in the clinical setting or whether it interferes with the detection of true myocardial infarction. Forty-nine patients who received defibrillations by patch electrodes were studied prospectively. We attempted to document the presence of myocardial injury with the following three commonly used modalities for the detection of myocardial infarction: serial electrocardiographic changes, serial creatine phosphokinase (CPK) and CPK-MB release, and technetium 99m pyrophosphate scanning. Fifteen patients received defibrillations by AICD patches at the time of AICD generator replacement. Nine patients received defibrillations at the time of new AICD lead placement. The average total energy delivered was 85 +/- 29 J. None of these patients had detectable myocardial injury. Ten patients had defibrillations by the AICD patches at the time of bypass operation. One patient in this group developed acute myocardial infarction in the inferior wall after posterior descending coronary bypass operation, as detected by electrocardiogram, 99mTc pyrophosphate scanning, and CPK-MB analysis. Fifteen patients were evaluated for spontaneous AICD discharges. Thirteen had a maximum of five consecutive shocks, and cumulative energy delivered was not greater than 330 J. None of these patients had detectable injury. Two patients had CPK-MB release of 15.3% and 7.5%, respectively. One of these patients had a positive 99mTc pyrophosphate scan. These two patients received 12 and 17 rapid and consecutive AICD discharges, respectively, with cumulative delivered energy of 360 and 510 J, respectively.

Avitall, B.; Port, S.; Gal, R.; McKinnie, J.; Tchou, P.; Jazayeri, M.; Troup, P.; Akhtar, M. (Univ. of Wisconsin-Milwaukee Clinical Campus (USA))

1990-05-01

221

Wall Covering  

NASA Technical Reports Server (NTRS)

The attractive wall covering shown below is one of 132 styles in the Mirror Magic II line offered by The General Tire & Rubber Company, Akron, Ohio. The material is metallized plastic fabric, a spinoff from space programs. Wall coverings are one of many consumer applications of aluminized plastic film technology developed for NASA by a firm later bought by King-Seeley Thermos Company, Winchester, Massachusetts, which now produces the material. The original NASA use was in the Echo 1 passive communications satellite, a "space baloon" made of aluminized mylar; the high reflectivity of the metallized coating enabled relay of communications signals from one Earth station to another by "bouncing" them off the satellite. The reflectivity feature also made the material an extremely efficient insulator and it was subsequently widely used in the Apollo program for such purposes as temperature control of spacecraft components and insulation of tanks for fuels that must be maintained at very low temperatures. I Used as a wall covering, the aluminized material offers extra insulation, reflects light and I resists cracking. In addition to General Tire, King-Seeley also supplies wall covering material to Columbus Coated Fabrics Division of Borden, Incorporated, Columbus, Ohio, among others.

1978-01-01

222

Arterial properties as determinants of time-varying myocardial stress in humans.  

PubMed

Myocardial and arterial load are time-varying phenomena. Despite their importance in myocardial function, the arterial properties that determine time-resolved myocardial wall stress are unknown. We aimed to assess arterial properties as determinants of time-resolved myocardial stress among 1214 men and women enrolled in the Asklepios Study. Time-resolved central pressure, flow, and left ventricular geometry were measured with carotid tonometry, Doppler, and speckle-tracking echocardiography, respectively, for computation of arterial load and ejection-phase time-varying myocardial wall stress. For any given end-diastolic left ventricular geometry and cardiac output, peak myocardial stress correlated directly with systemic vascular resistance (standardized ?=1.12; P<0.0001) and aortic characteristic impedance (standardized ?=0.17; P<0.0001). The ejection-phase stress-time integral correlated with systemic vascular resistance (standardized ?=1.06; P<0.0001), lower total arterial compliance (standardized ?=-0.13; P=0.0008), and earlier return of wave reflections (standardized ?=-0.10; P<0.0001) but not with reflection magnitude, whereas end-systolic wall stress correlated with systemic vascular resistance (standardized ?=1.06; P<0.0001) and reflection magnitude (standardized ?=0.12; P<0.0001). After adjustment for age, all of the measured arterial properties, end-diastolic left ventricular geometry, and cardiac output, women demonstrated greater peak (534 versus 507 kdyne/cm(2); P<0.0001), end-systolic (335 versus 320 kdyne/cm(2); P<0.0001), and ejection-phase stress-time integral (157 versus 142 kdyne · s · cm(-2); P<0.0001). In conclusion, different arterial properties have selective effects on time-resolved ejection-phase myocardial wall stress, which are not apparent from single-time point measurements. Women demonstrate less efficient myocardial-arterial coupling, with higher wall stress development for any given left ventricular geometry, arterial properties, and flow output. These observations may relate to the differential susceptibility of women to heart failure. PMID:22665121

Chirinos, Julio A; Segers, Patrick; Gillebert, Thierry C; Gupta, Amit K; De Buyzere, Marc L; De Bacquer, Dirk; St John-Sutton, Martin; Rietzschel, Ernst R

2012-07-01

223

Wall shear stress in intracranial aneurysms and adjacent arteries?  

PubMed Central

Hemodynamic parameters play an important role in aneurysm formation and growth. However, it is difficult to directly observe a rapidly growing de novo aneurysm in a patient. To investigate possible associations between hemodynamic parameters and the formation and growth of intracranial aneurysms, the present study constructed a computational model of a case with an internal carotid artery aneurysm and an anterior communicating artery aneurysm, based on the CT angiography findings of a patient. To simulate the formation of the anterior communicating artery aneurysm and the growth of the internal carotid artery aneurysm, we then constructed a model that virtually removed the anterior communicating artery aneurysm, and a further two models that also progressively decreased the size of the internal carotid artery aneurysm. Computational simulations of the fluid dynamics of the four models were performed under pulsatile flow conditions, and wall shear stress was compared among the different models. In the three aneurysm growth models, increasing size of the aneurysm was associated with an increased area of low wall shear stress, a significant decrease in wall shear stress at the dome of the aneurysm, and a significant change in the wall shear stress of the parent artery. The wall shear stress of the anterior communicating artery remained low, and was significantly lower than the wall shear stress at the bifurcation of the internal carotid artery or the bifurcation of the middle cerebral artery. After formation of the anterior communicating artery aneurysm, the wall shear stress at the dome of the internal carotid artery aneurysm increased significantly, and the wall shear stress in the upstream arteries also changed significantly. These findings indicate that low wall shear stress may be associated with the initiation and growth of aneurysms, and that aneurysm formation and growth may influence hemodynamic parameters in the local and adjacent arteries.

Wang, Fuyu; Xu, Bainan; Sun, Zhenghui; Wu, Chen; Zhang, Xiaojun

2013-01-01

224

Innate immune response after acute myocardial infarction and pharmacomodulatory action of tacrolimus in reducing infarct size and preserving myocardial integrity  

PubMed Central

Background This study investigated the association between innate immune reaction and myocardial damage after acute myocardial infarction (AMI) and anti-inflammatory role of tacrolimus in reducing infarct size. Male mini-pigs (n=18) were equally categorized into sham control (SC), untreated AMI (by ligation of left anterior descending coronary artery), and AMI-Tacrolimus (AMI-Tac) (0.5 mg intra-coronary injection 30 minutes post-AMI). Cardiac magnetic resonance imaging (MRI) was performed at post-AMI days 2, 5 and 21 before sacrificing the animals. Results By post-AMI day 21, left ventricular ejection fraction (LVEF) was lowest in untreated AMI animals, significantly higher in SC than in AMI-Tac group (all p<0.003). Infarct areas at basal, middle, and apical levels, numbers of CD14+ and iNOS+ cells in infarct area (IA) and peri-IA, and protein expression of CD14, CD68, and Ly6g from circulating inflammatory cells showed an opposite pattern compared with that of LVEF in all groups (all p<0.005). Protein expressions of MCP-1, MIP-1, TNF-?, NF-?B, iNOS, and IL-12 in IA and peri-IA exhibited an identical pattern compared to that of CD14, CD68, and Ly6g from circulating inflammatory cells (all p<0.01). Expressions of myocardial damage biomarkers in IA and peri-IA [?-H2AX, ?-myosin heavy chain (MHC), Smad3, TGF-?] were highest in AMI and higher in AMI-Tac than in SC, whereas expressions of myocardial integrity biomarkers (connexin43, mitochondrial cytochrome-C, ?-MHC, BMP-2, Smad1/5) were opposite to those of damage biomarkers (all p<0.001). Conclusion Innate immune responses were markedly augmented and LVEF was significantly reduced after AMI but were remarkably improved after tacrolimus treatment. PMID:24165293

2013-01-01

225

Precordial ST-segment depression during acute inferior myocardial infarction: clinical, scintigraphic and angiographic correlations  

SciTech Connect

The cause and associated pathophysiology of precordial ST-segment depression during acute inferior myocardial infarction (IMI) are controversial. To investigate this problem, electrocardiographic findings in 48 consecutive patients with acute IMI were prospectively compared with results of coronary angiography, submaximal exercise thallium-201 (/sup 201/Tl) scintigraphy and multigated blood pool imaging, all obtained 2 weeks after IMI, and with clinical follow-up at 3 months. Patients were classified according to the admission ECG obtained 3.3 +/- 3.1 hours after the onset of chest pain. Twenty-one patients (group A) had no or <1.0 mm ST-segment depression, and 27 (group B) had greater than or equal to1.0 mm ST-segment depression in two or more precordial (V/sub 1-6/) leads. Patients in group B had more prolonged chest pain after admission to the coronary care unit than those in group A (2.8 +/- 3.0 vs 1.2 +/- 1.1 hours, p<0.03), greater summed ST-segment elevation in leads II, III, aV/sub F/ (6.7 +/- 4.7 vs 3.3 +/- 4.5 mm, p<0.02), higher plasma peak creatine kinase levels (1133 +/- 781 vs 653 +/- 482 IU/l, p<0.01), a higher prevalence of ''true posterior'' infarction by ECG criteria (26% vs 5%, p<0.05), a lower radionuclide ejection fraction (46 +/- 9% vs 54 +/- 6%, p<0.001), more extensive infarct-related asynergy (p<0.001) and /sup 201/Tl perfusion abnormalities (p<0.01), more complications during hospitalization (p<0.03), and more cardiac events at 3 months (p<0.02). There were no significant differences between group A and group B in the extent of underlying coronary disease, prevalence of left anterior descending coronary artery disease, exercise-induced ST-segment depression or angina, /sup 201/Tl defects or wall motion abnormalities in anterior or septal segments.

Gibson, R.S.; Crampton, R.S.; Watson, D.D.; Taylor, G.J.; Carabello, B.A.; Holt, N.D.; Beller, G.A.

1982-10-01

226

Myocardial mechanics in cardiomyopathies.  

PubMed

Cardiomyopathies are a heterogeneous group of diseases that can be phenotypically recognized by specific patterns of ventricular morphology and function. The authors summarize recent clinical observations that mechanistically link the multidirectional components of left ventricular (LV) deformation with morphological phenotypes of cardiomyopathies for offering key insights into the transmural heterogeneity of myocardial function. Subendocardial dysfunction predominantly alters LV longitudinal shortening, lengthening and suction performance and contributes to the phenotypic patterns of heart failure (HF) with preserved ejection fraction (EF) seen with hypertrophic and restrictive patterns of cardiomyopathy. On the other hand, a more progressive transmural disease results in reduction of LV circumferential and twist mechanics leading to the phenotypic pattern of dilated cardiomyopathy and the clinical syndrome of HF with reduced (EF). A proper characterization of LV transmural mechanics, energetics, and space-time distributions of pressure and shear stress may allow recognition of early functional changes that can forecast progression or reversal of LV remodeling. Furthermore, the interactions between LV muscle and fluid mechanics hold the promise for offering newer mechanistic insights and tracking impact of novel therapies. PMID:25081406

Modesto, Karen; Sengupta, Partho P

2014-01-01

227

MYOCARDIAL AKT: THE OMNIPRESENT NEXUS  

PubMed Central

One of the greatest examples of integrated signal transduction is revealed by examination of effects mediated by AKT kinase in myocardial biology. Positioned at the intersection of multiple afferent and efferent signals, AKT exemplifies a molecular sensing node that coordinates dynamic responses of the cell in literally every aspect of biological responses. The balanced and nuanced nature of homeostatic signaling is particularly essential within the myocardial context, where regulation of survival, energy production, contractility, and response to pathological stress all flow through the nexus of AKT activation or repression. Equally important, the loss of regulated AKT activity is primarily the cause or consequence of pathological conditions leading to remodeling of the heart and eventual decompensation. This review presents an overview compendium of the complex world of myocardial AKT biology gleaned from more than a decade of research. Summarization of the widespread influence that AKT exerts upon myocardial responses leaves no doubt that the participation of AKT in molecular signaling will need to be reckoned with as a seemingly omnipresent regulator of myocardial molecular biological responses. PMID:21742795

Sussman, Mark A.; Volkers, Mirko; Fischer, Kimberlee; Bailey, Brandi; Cottage, Christopher T.; Din, Shabana; Gude, Natalie; Avitabile, Daniele; Alvarez, Roberto; Sundararaman, Balaji; Quijada, Pearl; Mason, Matt; Konstandin, Mathias H.; Malhowski, Amy; Cheng, Zhaokang; Khan, Mohsin; McGregor, Michael

2013-01-01

228

Restoration of autophagic flux in myocardial tissues is required for cardioprotection of sevoflurane postconditioning in rats  

PubMed Central

Aim: Sevoflurane postconditioning (SpostC) has been shown to protect the heart from ischemia-reperfusion (I/R) injury. In this study, we examined whether SpostC affected autophagic flux in myocardial tissues that contributed to its cardioprotective effects in rats following acute I/R injury. Methods: SD rats underwent 30 min of left anterior descending coronary artery ligation followed by 120 min of reperfusion. The rats were subjected to inhalation of 2.4% (v/v) sevoflurane during the first 5 min of reperfusion, and chloroquine (10 mg/kg, ip) was injected 1 h before I/R. Myocardial infarct size was estimated using TTC staining. Autophagosomes in myocardial tissues were detected under TEM. Expression of LC3B-II, beclin-1, p62/SQSTM1, cathepsin B, caspase-3 and cleaved PARP was assessed using Western blot analysis. Plasma cardiac troponin I was measured using ELISA. Cardiomyocyte apoptosis was evaluated with TUNEL staining. Results: I/R procedure produced severe myocardium infarct and apoptosis accompanied by markedly increased number of autophagosomes, as well as increased levels of LC3B-II, beclin-1 and p62 in myocardial tissues. SpostC significantly reduced infarct size, attenuated myocardial apoptosis, restored intact autophagic flux and improved the lysosomal function in myocardial tissues. Administration of chloroquine that blocked autophagic flux abrogated the cardioprotective effects of SpostC. Conclusion: SpostC exerts its cardioprotective effects in rats following I/R injury via restoring autophagic flux in myocardial tissues. PMID:24793309

Zhang, Yu-lin; Yao, Yun-tai; Fang, Neng-xin; Zhou, Cheng-hui; Gong, Jun-song; Li, Li-huan

2014-01-01

229

Myocardial perfusion imaging with technetium-99m sestamibi SPECT in the evaluation of coronary artery disease  

SciTech Connect

Technetium-99m (Tc-99m) sestamibi is a new myocardial perfusion imaging agent that offers significant advantages over thallium-201 (Tl-201) for myocardial perfusion imaging. The results of the current clinical trials using acquisition and processing parameters similar to those for Tl-201 and a separate (2-day) injection protocol suggest that Tc-99m sestamibi and Tl-201 single photon emission computed tomography (SPECT) provide similar information with respect to detection of myocardial perfusion defects, assessment of the pattern of defect reversibility, overall detection of coronary artery disease (CAD) and detection of disease in individual coronary arteries. Tc-99m sestamibi SPECT appears to be superior to Tc-99m sestamibi planar imaging because the former provides a higher defect contrast and is more accurate for detection of disease in individual coronary arteries. Research is currently under way addressing optimization of acquisition and processing of Tc-99m sestamibi studies and development of quantitative algorithms for detection and localization of CAD and sizing of transmural and nontransmural myocardial perfusion defects. It is expected that with the implementation of the final results of these new developments, further significant improvement in image quality will be attained, which in turn will further increase the confidence in image interpretation. Development of algorithms for analysis of end-diastolic myocardial images may allow better evaluation of small and nontransmural myocardial defects. Furthermore, gated studies may provide valuable information with respect to regional myocardial wall motion and wall thickening. With the implementation of algorithms for attenuation and scatter correction, the overall specificity of Tc-99m sestamibi SPECT should improve significantly. 32 references.

Maddahi, J.; Kiat, H.; Van Train, K.F.; Prigent, F.; Friedman, J.; Garcia, E.V.; Alazraki, N.; DePuey, E.G.; Nichols, K.; Berman, D.S. (Cedars-Sinai Medical Center, Los Angeles, CA (USA))

1990-10-16

230

Berlin Wall  

NSDL National Science Digital Library

You and your classmates have been sent to Germany to learn about the Berlin Wall. At the end of the trip you will return to your school and be asked questions about your experiences and what you have learned. You will read your task first, then go and read the process you will follow, next read through the learning advice, use the resources provided to answer the questions, and after you have finished all those steps go to the conclusion. Good Luck and have a FUN trip!!! TASK Your task is to visit sites related to the Berlin Wall and find the answers to the following questions at these sites. 1. What four countries occupied parts of Berlin? 2. What country was in charge of the area surrounding Berlin? 3. What was the Berlin Blockade? Why did it end? 4. Why was ...

B, Miss

2007-06-21

231

A PNIPAAm-based thermosensitive hydrogel containing SWCNTs for stem cell transplantation in myocardial repair.  

PubMed

Poly (N-isopropylacrylamide) (PNIPAAm) hydrogel was a widely used carrier in therapeutic agent delivery. However, its bioactivities for encapsulated cells were not satisfactory. In the study, we aimed to determine whether modification with single-wall carbon nanotubes (SWCNTs) could improve the bioactivitis, especially supportive adhesion of PNIPAAm to encapsulated cells and favor their efficacy in myocardial repair. A thermosensitive SWCNTs-modified PNIPAAm hydrogel (PNIPAAm/SWCNTs) were prepared by incorporating the SWCNTs into base PNIPAAm hydrogel. The bioactivities of the resulted hydrogel to brown adipose-derived stem cells (BASCs) were evaluated and compared with the base PNIPAAm hydrpgel in vitro. Then, the PNIPAAm-containing hydrogel was used as carrier for imtromyocardial delivery of BASCs in rats with myocardial infarction. The efficacy of PNIPAAm/SWCNTs hydrogel in stem cell-based myocardial repair was systematically evaluated. In vitro study showed that the PNIPAAm/SWCNTs hydrogel demonstrated significantly higher bioactivities to encapsulated BASCs compared with onefold PNIPAAm hydrogel, including promoting cell adhesion and proliferation. When used as carrier for intramyocardial delivery of BASCs after myocardial infarction, the PNIPAAm/SWCNTs hydrogel significantly enhanced the engraftment of seeding cells in infarct myocardium and augmented their therapeutic efficacies in myocardial infarction (MI). The data provided a supportive evidence for the myocardial application of the SWCNTs-modified hydrogel and offered a new perspective in development or improvement of cardiac tissue engineering scaffold. PMID:24746964

Li, Xia; Zhou, Jin; Liu, Zhiqiang; Chen, Jun; Lü, Shuanghong; Sun, Hongyu; Li, Junjie; Lin, Qiuxia; Yang, Boguang; Duan, Cuimi; Xing, Malcolm Mengqiu; Wang, Changyong

2014-07-01

232

Gullied Wall  

NASA Technical Reports Server (NTRS)

13 May 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows gullies on northern wall of a south mid-latitude crater.

Location near: 35.8oS, 220.9oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Spring

2005-01-01

233

A technique to salvage endodontically compromised maxillary anterior tooth.  

PubMed

A complication of endodontic treatment is over-preparation of the tooth structure in an attempt to access calcified pulp chambers and root canals. This could result in thin root walls that might compromise the long-term prognosis of the tooth. There are various treatment options when such a complication occurs, among them, extraction of the compromised tooth and its replacement with a dental implant. This clinical report describes a nonsurgical, multidisciplinary treatment alternative where a maxillary anterior tooth with a thinned root wall was successfully saved by repairing the damaged root to its original thickness using a composite resin material and subsequently restoring with a cast post and core and a crown. PMID:24654367

Comut, Alper; Foran, Denise; Cunningham, Ralph P

2014-01-01

234

Effect of coronary artery recanalization on right ventricular function in patients with acute myocardial infarction  

SciTech Connect

The effects of coronary artery recanalization by intracoronary administration of streptokinase on left ventricular function during acute myocardial infarction have received increasing attention in recent years. Although myocardial dysfunction is often more pronounced in the right ventricle than in the left ventricle in patients with acute inferior wall myocardial infarction, the effect of coronary artery recanalization on right ventricular dysfunction has not been previously addressed. Accordingly, in this investigation, 54 patients who participated in a prospective, controlled, randomized trial of recanalization during acute myocardial infarction were studied. Among 30 patients with inferior wall infarction, 19 had right ventricular dysfunction on admission; 11 of these 19 had positive uptake of technetium-99m pyrophosphate in the right ventricle, indicative of right ventricular infarction. Patients with successful recanalization exhibited improved right ventricular ejection fraction from admission to day 10. However, control patients and patients who did not undergo recanalization also exhibited improvement. These data indicate that the right ventricular dysfunction commonly associated with inferior wall infarction is often transient, and improvement is the rule, irrespective of early recanalization of the infarct vessel.

Verani, M.S.; Tortoledo, F.E.; Batty, J.W.; Raizner, A.E.

1985-05-01

235

Prediction of coronary plaque location on arteries having myocardial bridge, using finite element models.  

PubMed

This study was performed to evaluate the influences of the myocardial bridges on the plaque initializations and progression in the coronary arteries. The wall structure is changed due to the plaque presence, which could be the reason for multiple heart malfunctions. Using simplified parametric finite element model (FE model) of the coronary artery having myocardial bridge and analyzing different mechanical parameters from blood circulation through the artery (wall shear stress, oscillatory shear index, residence time), we investigated the prediction of "the best" position for plaque progression. We chose six patients from the angiography records and used data from DICOM images to generate FE models with our software tools for FE preprocessing, solving and post-processing. We found a good correlation between real positions of the plaque and the ones that we predicted to develop at the proximal part of the myocardial bridges with wall shear stress, oscillatory shear index and residence time. This computer model could be additional predictive tool for everyday clinical examination of the patient with myocardial bridge. PMID:25139775

Nikoli?, Dalibor; Radovi?, Miloš; Aleksandri?, Sr?an; Tomaševi?, Miloje; Filipovi?, Nenad

2014-11-01

236

Insulin regulation of myocardial autophagy.  

PubMed

Autophagy is a conserved cellular process that plays an important role in cardiovascular homeostasis. Basal levels of autophagy are required for the maintenance of organellar quality control. Autophagy is dynamically regulated in the heart in the fasting to re-feeding transition. Insulin signaling plays an important role in the regulation of myocardial fuel metabolism, mitochondrial function and cellular growth. Recent studies have suggested an important role for insulin signaling in the regulation of myocardial autophagy. This dynamic regulation of autophagy induction during fasting may contribute to organellar homeostasis and if perturbed under conditions of hyperinsulinemia could contribute to accelerated cardiac aging. (Circ J 2014; 78: 2569-2576). PMID:25327953

Riehle, Christian; Abel, E Dale

2014-10-24

237

Late gadolinium cardiovascular magnetic resonance in the assessment of myocardial viability.  

PubMed

Delayed-enhancement magnetic resonance imaging is a viability imaging technique that has been demonstrated in both animal and patient studies to accurately identify and characterize the presence and transmural extent of myocardial scarring. The precise information regarding the presence, location and extent of myocardial scarring has been shown to be useful in predicting the likelihood of functional recovery of dysfunctional myocardium after revascularization. Perhaps, more importantly, the ability to visualize the extent of viable and nonviable myocardium across the ventricular wall allows one to approach viability as a continuum rather than in a binary manner, providing a better reflection of the underlying physiology. PMID:16118541

Elliott, Michael D; Kim, Raymond J

2005-09-01

238

Mechanisms of cell death in acute myocardial infarction: pathophysiological implications for treatment  

PubMed Central

The purpose of this review is to draw attention to the growing list of pathophysiological phenomena occurring in blood, the vessel wall and cardiac tissue during myocardial infarction. A further aim is to point to the complexity of factors, contributing to cardiac dysfunction and the implications for therapy, aimed at limiting myocardial cell death. Not all pathophysiological mechanisms have been elucidated yet, indicating the necessity for further research in this area. In addition we describe interventions which have shown promise in animal studies, those which may show promise in humans, and those which are accepted as therapies of choice.

de Zwaan, C.; Daemen, M.J.A.P.; Hermens, W.Th.

2001-01-01

239

Thallium-201 myocardial scintigraphy in acute myocardial infarction and ischemia  

SciTech Connect

Thallium-201 scintigraphy provides a sensitive and reliable method of detecting acute myocardial infarction and ischemia when imaging is performed with understanding of the temporal characteristics and accuracy of the technique. The results of scintigraphy are related to the time interval between onset of symptoms and time of imaging. During the first 6 hr after chest pain almost all patients with acute myocardial infarction and approximately 50% of the patients with unstable angina will demonstrate /sup 201/TI pefusion defects. Delayed imaging at 2-4 hr will permit distinction between ischemia and infarction. In patients with acute myocardial infarction, the size of the perfusion defect accurately reflects the extent of the infarcted and/or jeopardized myocardium, which may be used for prognostic stratification. In view of the characteristics of /sup 201/TI scintigraphy, the most practical application of this technique is in patients in whom myocardial infarction has to be ruled out, and for early recognition of patients at high risk for complications.

Wackers, F.J.

1982-04-01

240

TachoSil for postinfarction ventricular free wall rupture.  

PubMed

Despite a decline in the last three decades, postinfarction ventricular free wall rupture still complicates more than 3% of acute ST-elevation myocardial infarctions and remains a surgical challenge. TachoSil (Nycomed, Zurich, Switzerland) is an equine collagen patch coated with human fibrinogen and human thrombin, which has recently been used for haemostasis in cardiovascular surgery, but its potential usefulness in free wall rupture has not been reported. Initial clinical experience with an on-pump sutureless technique without cardioplegia, using wide TachoSil patching to achieve free wall rupture repair, has been described. PMID:22419793

Pocar, Marco; Passolunghi, Davide; Bregasi, Alda; Donatelli, Francesco

2012-06-01

241

TachoSil® for postinfarction ventricular free wall rupture  

PubMed Central

Despite a decline in the last three decades, postinfarction ventricular free wall rupture still complicates more than 3% of acute ST-elevation myocardial infarctions and remains a surgical challenge. TachoSil® (Nycomed, Zurich, Switzerland) is an equine collagen patch coated with human fibrinogen and human thrombin, which has recently been used for haemostasis in cardiovascular surgery, but its potential usefulness in free wall rupture has not been reported. Initial clinical experience with an on-pump sutureless technique without cardioplegia, using wide TachoSil® patching to achieve free wall rupture repair, has been described. PMID:22419793

Pocar, Marco; Passolunghi, Davide; Bregasi, Alda; Donatelli, Francesco

2012-01-01

242

Detection of multivessel disease in patients with sustained myocardial infarction by thallium 201 myocardial scintigraphy: No additional value of quantitative analysis  

SciTech Connect

This study was performed to determine the value of visual and quantitative thallium 201 scintigraphy for the detection of multivessel disease in 67 patients with a sustained transmural myocardial infarction. Also the viability of the myocardial regions corresponding to pathologic Q-waves was evaluated. Of the 67 patients, 51 patients had multivessel coronary artery disease (76%). The sensitivity of the exercise test was 53%, of thallium scintigraphy 69%, when interpreted visually, and 67%, when analysed quantitatively. The specificity of these methods was 69%, 56%, and 50%, respectively. Sixty-two infarct-related flow regions were detected by visual analysis of the thallium scans, total redistribution was observed in 11/62 (18%) of patients, partial redistribution in 26/62 (42%), and no redistribution in 25/62 (40%) of patients. The infarct-related areas with total redistribution on the thallium scintigrams were more likely to be associated with normal or hypokinetic wall motion (7/11: 64%) than the areas with a persistent defect (7/25:28%) (P = 0.05), which were more related with akinetic or dyskinetic wall motion. Based on our results, it is concluded that (1) both visual and quantitative analysis of thallium exercise scintigraphy have limited value to predict the presence or absence of multivessel coronary artery disease in patients with sustained myocardial infarction, and (2) exercise-induced thallium redistribution may occur within the infarct zone, suggesting the presence of viable but jeopardized myocardium in presumed fibrotic myocardial areas.

Niemeyer, M.G.; Pauwels, E.K.; van der Wall, E.E.; Cramer, M.J.; Verzijlbergen, J.F.; Zwinderman, A.H.; Ascoop, C.A. (Merwede Hospital, Dordrecht (Netherlands))

1989-01-01

243

Wellens syndrome associated with prominent anterior QRS forces: an expression of left septal fascicular block?  

PubMed

Wellens syndrome is a clinical-electrocardiographic entity also referred to as left anterior descending (LAD) coronary T-wave syndrome or acute coronary T-wave syndrome. It is a complex of symptoms and signals indicating the existence of an undesirable condition secondary to critical high-grade proximal stenosis of the LAD coronary artery characterized by the association of prior history of acute coronary syndrome with little or no elevation of markers of myocardial damage (unstable angina) and characteristic electrocardiographic changes consistent with subepicardial anterior ischemic pattern (persistently symmetrical, deep negative and broad-based T waves) or plus-minus T waves with inversion of the terminal portion in the LAD coronary artery territory (V1 through V5 or V6). We present a case of a variant of Wellens syndrome that reveals association and, transitorily, the criteria described in literature for left septal fascicular block. PMID:18649894

Riera, Andrés Ricardo Pérez; Ferreira, Celso; Ferreira Filho, Celso; Dubner, Sergio; Schapachnik, Edgardo; Uchida, Augusto H; Moffa, Paulo; Zhang, Li; de Luna, Antoni Bayes

2008-01-01

244

Cardiac imaging and myocardial kinetics of technetium-tertiary butyl-isonitrile during dipyridamole-induced hyperemia  

SciTech Connect

To determine the myocardial kinetics of technetium-tertiary-butyl-isonitrile (Tc-TBI) during dipyridamole-induced hyperemia, the circumflex coronary arteries (LCX) of 15 dogs were partially occluded. Dipyridamole was then infused intravenously over 4 minutes, creating hyperemic flows in the anterior descending (LAD) coronary system. Tc-TBI was administered, then LAD and LCX regional myocardial Tc-TBI activities were continuously monitored with miniature detectors and gamma camera imaging over 3 hours. Microsphere-determined regional myocardial blood flows demonstrated an LCX/LAD flow ratio of 0.81 +/- 0.21 at rest and 0.45 +/- 0.24 (SD) during dipyridamole infusion. Three-hour fractional Tc-TBI clearance rates were minimal and were equal in the LAD (0.14 +/- 0.11) and LCX (0.13 +/- 0.12) zones (p = ns). Excellent gamma camera images, demonstrating the LCX defect, were obtained in all dogs. The correlation coefficient was 0.98 for regional myocardial blood flow vs initial Tc-TBI distribution. In conclusion: (1) Dipyridamole vasodilation unmasked coronary stenoses despite no flow disparities at rest. (2) The initial distribution of Tc-TBI is proportional to regional myocardial blood flow. (3) There is minimal washout and no redistribution into the initial defect over time, and thus image quality is stable over time. (4) Tc-TBI myocardial kinetics may be applicable to closely related agents currently being developed.

Okada, R.D.; Williams, S.J.; Glover, D.K.; Dragatokis, D.

1988-10-01

245

Regional myocardial extraction of a radioiodinated branched chain fatty acid during right ventricular pressure overload due to acute pulmonary hypertension  

SciTech Connect

To determine whether branched chain fatty acid extraction is reduced during right ventricular (RV) dysfunction due to acute pulmonary artery hypertension, studies were done in 6 anesthetized dogs. Regional branched chain fatty acid extraction was measured by comparing the myocardial uptake of I-125 labeled 15-(p-(iodophenyl))-3-methylpentadecanoic acid (I-PDA) to myocardial blood flow. Acute pulmonary hypertension was induced by incremental intravenous injection of 100 micron diameter glass beads into six pentobarbital anesthetized, mechanically ventilated dogs. Myocardial blood flow was measured by radiolabeled microspheres both under baseline conditions and during pulmonary hypertension. Mean RV pressure rose from 12 +- 2 (mean +- SEM) to 30 +-3mmHg resulting in a 225 +- 16% increase in RV stroke work. RV ejection fraction, as assessed by gated blood pool scans fell from 39 +- 2 to 18 +- 2%. Left ventricular (LV) pressures, stroke work and ejection fraction were unchanged. Myocardial blood flow increased 132 + 59% in the RV free wall and 67 +- 22% in the RV septum. LV blood flow was unchanged. Despite increased RV work and myocardial blood flow, no differences were noted in the branched chain fatty acid extraction ratios among LV or RV free walls or septum. The authors conclude that early RV dysfunction associated with pulmonary artery hypertension is not due to inadequate myocardial blood flow or branched chain fatty acid extraction.

Hurford, W.; Lowenstein, E.; Zapol, W.; Barlai-Kovach, M.; Livni, E.; Elmaleh, D.R.; Strauss, H.W.

1985-05-01

246

Myocardial contusion following nonfatal blunt chest trauma  

SciTech Connect

Currently available diagnostic techniques for myocardial contusion following blunt chest trauma were evaluated. We investigated 30 patients prospectively over a period of 1 year for the presence of myocardial contusion. Among the 30 patients, eight were found to have myocardial contusion on the basis of abnormal electrocardiograms, elevated creatine phosphokinase MB fraction (CPK-MB), and positive myocardial scan. Myocardial scan was positive in seven of eight patients (87.5%). CPK-MB fraction was elevated in four of eight patients (50%). Definitive electrocardiographic changes were seen in only two of eight patients (25%). It appears that myocardial scan using technetium pyrophosphate and CPK-MB fraction determinations are the most reliable aids in diagnosis of myocardial contusion following blunt chest trauma.

Kumar, S.A.; Puri, V.K.; Mittal, V.K.; Cortez, J.

1983-04-01

247

Anterior cruciate: methods of physical examination.  

PubMed

Tear of the anterior cruciate ligament is a common, serious injury. Since the long-range consequences of uncorrected anterior cruciate incompetence are better understood, and surgical and rehabilitative measures improved, early accurate diagnosis is increasingly important. Besides a careful history, diagnosis requires the use of specific physical examination methods to reproduce the symptomatic subluxation (anterior shift or internal rotation) and to assess functional performance of the knee. PMID:21286055

Grant, J; Kirby, R L

1982-02-01

248

Spousal Adjustment to Myocardial Infarction.  

ERIC Educational Resources Information Center

This paper reviews the literature on the stresses and coping strategies of spouses of patients with myocardial infarction (MI). It attempts to identify specific problem areas of adjustment for the spouse and to explore the effects of spousal adjustment on patient recovery. Chapter one provides an overview of the importance in examining the…

Ziglar, Elisa J.

249

[Sewer gas induced myocardial toxicity].  

PubMed

We report the case of a 19 year-old worker who collapsed after acute exposure to sewer gas. He rapidly developed cardiorespiratory failure with electrocardiographic, echocardiographic and laboratory findings of myocardial involvement. The mainstay of the therapy was mainly supportive treatment with a successful outcome. PMID:25189024

Antonelli, Dante; Sabanchiev, Avi; Rosner, Ehud; Turgeman, Yoav

2014-07-01

250

Imaging techniques for myocardial inflammation  

SciTech Connect

Dilated cardiomyopathy (DC) represents a heterogeneous group of disorders which results in morbidity and mortality in young individuals. Recent evidence suggests that a subset of these patients have histologic evidence of myocarditis which is potentially treatable with immunosuppression. The identification of myocardial inflammation may therefore lead to development of therapeutic regimens designed to treat the cause rather than the effect of the myocardial disease. Ultimately, this may result in improvement in the abysmal prognosis of DC. The currently accepted technique for identification of active myocardial inflammation is endomyocardial biopsy. This technique is not perfect, however, since pathologic standards for the diagnosis of myocarditis have not been established. Furthermore, focal inflammation may give rise to sampling error. The inflammation-avid radioisotope gallium-67 citrate has been used as an adjunct to biopsy improving the yield of myocarditis from 7 percent to 36 percent. Serial imaging correlates well to biopsy results. Future studies are designed to study the applicability of lymphocyte labelling techniques to myocardial inflammatory disease.

O'Connell, J.B.; Henkin, R.E.; Robinson, J.A.

1986-03-01

251

Biomarkers in acute myocardial infarction.  

PubMed

Myocardial infarction causes significant mortality and morbidity. Timely diagnosis allows clinicians to risk stratify their patients and select appropriate treatment. Biomarkers have been used to assist with timely diagnosis, while an increasing number of novel markers have been identified to predict outcome following an acute myocardial infarction or acute coronary syndrome. This may facilitate tailoring of appropriate therapy to high-risk patients. This review focuses on a variety of promising biomarkers which provide diagnostic and prognostic information. Heart-type Fatty Acid Binding Protein and copeptin in combination with cardiac troponin help diagnose myocardial infarction or acute coronary syndrome in the early hours following symptoms. An elevated N-Terminal Pro-B-type Natriuretic Peptide has been well validated to predict death and heart failure following a myocardial infarction. Similarly other biomarkers such as Mid-regional pro-Atrial Natriuretic Peptide, ST2, C-Terminal pro-endothelin 1, Mid-regional pro-Adrenomedullin and copeptin all provide incremental information in predicting death and heart failure. Growth differentiation factor-15 and high-sensitivity C-reactive protein predict death following an acute coronary syndrome. Pregnancy associated plasma protein A levels following chest pain predicts risk of myocardial infarction and revascularisation. Some biomarkers such as myeloperoxidase and high-sensitivity C-reactive protein in an apparently healthy population predicts risk of coronary disease and allows clinicians to initiate early preventative treatment. In addition to biomarkers, various well-validated scoring systems based on clinical characteristics are available to help clinicians predict mortality risk, such as the Thrombolysis In Myocardial Infarction score and Global Registry of Acute Coronary Events score. A multimarker approach incorporating biomarkers and clinical scores will increase the prognostic accuracy. However, it is important to note that only troponin has been used to direct therapeutic intervention and none of the new prognostic biomarkers have been tested and proven to alter outcome of therapeutic intervention. Novel biomarkers have improved prediction of outcome in acute myocardial infarction, but none have been demonstrated to alter the outcome of a particular therapy or management strategy. Randomised trials are urgently needed to address this translational gap before the use of novel biomarkers becomes common practice to facilitate tailored treatment following an acute coronary event. PMID:20529285

Chan, Daniel; Ng, Leong L

2010-01-01

252

Myocardial imaging with cesium-130  

SciTech Connect

Recently comparative studies using nitrogen-13 ammonia and cesium-130 have shown strikingly different myocardial localization patterns in the same subjects with ischemic heart disease. Initial localization of ammonia, an avidly extracted agent, reflects the perfusion pattern in viable myocardial tissue. The myocardial localization of cesium ion, taking place more slowly over 15 to 20 minutes, is apparently much less flow dependent, causing uptake defects shown with ammonia to be largely filled in. Cesium thus appears to provide information on the extent of the viable myocardial mass, apart from perfusion. Cesium-130 (t1/2 30 m) decays by positron emission and electron capture. The whole body radiation absorbed dose, assuming uniform distribution, is 24 mrad/mCi. While abundant production of Cs-130 results from proton bombardment of natural xenon (Xe-130(rho,n)Cs-130) at 15 MeV, small amounts of Cs-129, -131, and -132 are also produced, and enriched Xe-130 is not available. Alternatively almost completely uncontaminated Cs-130 is available by alpha bombardment of natural I-127. Anhydrous sodium iodide is dissolved in acetone and a thin layer (approx. =20 mg per centimeter squared) is evaporated onto the gold plated tip of the internal target backing which is oscillated vertically to spread out the area upon which the beam is incident. The target surface is inclined 2.5 degrees to the beam giving a power density of about 400 watts per centimeter squared at 100..mu..A which is adequately handled by water cooling. A 30-minute bombardment yields 4 to 5 mCi of Cs-130 which is dissolved directly from the target. This approach appears to offer a new and helpful method for evaluating ischemic heart disease by permitting evaluation of viable myocardial mass.

Harper, P.V.; Resnekov, L.; Stark, V.; Odeh, N.

1984-01-01

253

Electrocardiograms Corresponding to the Development of Myocardial Infarction in Anesthetized WHHLMI Rabbits (Oryctolagus cuniculus), an Animal Model for Familial Hypercholesterolemia  

PubMed Central

The aim of this study was to determine whether features indicative of myocardial ischemia occur in the electrocardiograms (ECG) in myocardial infarction-prone Watanabe heritable hyperlipidemic (WHHLMI) rabbits, an animal model for human familial hypercholesterolemia. ECG were recorded in 110 anesthetized WHHLMI rabbits (age, 10 to 39 mo) by using unipolar and bipolar limb leads with or without chest leads. We noted the following electrocardiographic changes: T wave inversion (37.4%), ST segment depression (31.8%), deep Q wave (16.3%), reduced R wave amplitude (7.3%), ST segment elevation (2.7%), and high T wave (1.8%). These ECG changes resembled those in human patients with coronary heart disease. Histopathologic examination revealed that the left ventricular wall showed acute myocardial lesions, including loss of cross-striations, vacuolar degeneration, coagulation necrosis of cardiac myocytes, and edema between myofibrils, in addition to chronic myocardial lesions such as myocardial fibrosis. The coronary arteries that caused these ECG changes were severely stenosed due to atherosclerotic lesions. Ischemic ECG changes corresponded to the locations of the myocardial lesions. Normal ECG waveforms were similar between WHHLMI rabbits and humans, in contrast to the large differences between rabbits and mice or rats. In conclusion, ischemic ECG changes in WHHLMI rabbits reflect the location of myocardial lesions, making this model useful for studying coronary heart disease. PMID:23114045

Kobayashi, Tsutomu; Ito, Takashi; Yamada, Satoshi; Kuniyoshi, Nobue; Shiomi, Masashi

2012-01-01

254

Myocardial infarction secondary to premature coronary artery disease as the initial major manifestation of systemic lupus erythematosus.  

PubMed

A 32-year-old woman admitted to the emergency department was diagnosed with acute anterior myocardial infarction, treated with thrombolytics and referred for angiography on the basis of her age. The patient was then referred for angioplasty with the diagnosis of an atherosclerotic lesion in the left anterior descending (LAD) coronary artery. Successful treatment of the lesion by primary stenting ensued. Laboratory findings revealed a state of hypercoagulability as well as some collagen fibre disease. The final diagnosis, confirmed by a rheumatologist, was systemic lupus erythematosus (SLE) with premature atherosclerosis of the LAD in addition to hypercoagulability. A Medline search of the literature revealed limited previous reports of myocardial infarction due to premature coronary artery disease as the first manifestation in SLE. PMID:18568176

Kassaian, S E; Goodarzynejad, H; Darabian, S; Basiri, Z

2008-01-01

255

Myocardial redistribution of technetium-99m-methoxyisobutyl isonitrile (SESTAMIBI)  

SciTech Connect

To determine whether technetium-99m-hexakis-2-methoxyisobutyl isonitrile (SESTAMIBI) remains fixed in the myocardium following its initial uptake or undergoes time-related redistribution, anesthetized dogs underwent occlusion of the anterior descending coronary artery for 6 min, followed by 3-hr reperfusion. Technetium-99m-SESTAMIBI and thallium-201 (201Tl) were injected intravenously after 1 min occlusion and regional myocardial blood flow was measured with radioactive microspheres. Tomographic imaging of Tc-SESTAMIBI revealed a perfusion defect with slight but definite filling in over 2 hr. Quantitative analysis indicated a significant rise in the nadir and decrease in the width of the defect in circumferential profile curves. After 3-hr of reperfusion, Tc-SESTAMIBI activity in the previously ischemic area was always greater than the activity of microspheres injected during coronary occlusion (mean normalized values, 0.32 versus 0.11, p less than 0.0001). Our results indicate that following transient ischemia and reperfusion, Tc-SESTAMIBI clearly undergoes myocardial redistribution, although more slowly and less completely than {sup 201}Tl.

Li, Q.S.; Solot, G.; Frank, T.L.; Wagner, H.N. Jr.; Becker, L.C. (Johns Hopkins Medical Institutions, Baltimore, MD (USA))

1990-06-01

256

Full myocardial revascularization with bilateral internal mammary artery Y grafts  

PubMed Central

Background Bilateral internal mammary artery (BIMA) grafting in coronary artery surgery provides better long term outcomes than single internal mammary artery and saphenous vein grafting but the optimum configuration of BIMAs has not been established. This study analyzed perioperative and late outcomes of patients who underwent BIMA grafting with a composite Y configuration. Methods Patients (n=922) who underwent BIMA Y grafting were identified from a cardiac surgical database and then cross matched against hospital and cardiology databases and the state death register to identify episodes of repeat coronary angiography, cardiac surgical re-intervention and death. Analysis of repeat angiography was performed after retrieval of the angiogram reports. Results In 95% of patients, full myocardial revascularization was achieved with BIMAs alone, using a composite Y configuration with an average of 4.1 IMA to coronary artery anastomoses per patient. The perioperative mortality was 1.5% and the 5-, 10- and 15-year survival estimates were 95%, 87% and 77% respectively. Analysis of 166 symptom-driven post-discharge coronary angiograms showed grafts to the left anterior descending artery and increasing severity of coronary artery stenosis at preoperative angiography as predictors of anastomotic patency. Conclusions Full myocardial revascularization can be achieved with reasonable safety in most patients with triple vessel disease and good left ventricular function, and provides good late survival. PMID:23977621

Naidoo, Rishendran; Byth, Karen; Chen, Cheng; Denniss, A. Robert

2013-01-01

257

Hypoxic conditioning suppresses nitric oxide production upon myocardial reperfusion.  

PubMed

Physiologically modulated concentrations of nitric oxide (NO) are generally beneficial, but excessive NO can injure myocardium by producing cytotoxic peroxynitrite. Recently we reported that intermittent, normobaric hypoxia conditioning (IHC) produced robust cardioprotection against infarction and lethal arrhythmias in a canine model of coronary occlusion-reperfusion. This study tested the hypothesis that IHC suppresses myocardial nitric oxide synthase (NOS) activity and thereby dampens explosive, excessive NO formation upon reperfusion of occluded coronary arteries. Mongrel dogs were conditioned by a 20 d program of IHC (FIO(2) 9.5-10%; 5-10 min hypoxia/cycle, 5-8 cycles/d with intervening 4 min normoxia). One day later, ventricular myocardium was sampled for NOS activity assays, and immunoblot detection of the endothelial NOS isoform (eNOS). In separate experiments, myocardial nitrite (NO(2)(-)) release, an index of NO formation, was measured at baseline and during reperfusion following 1 h occlusion of the left anterior descending coronary artery (LAD). Values in IHC dogs were compared with respective values in non-conditioned, control dogs. IHC lowered left and right ventricular NOS activities by 60%, from 100-115 to 40-45 mU/g protein (P < 0.01), and decreased eNOS content by 30% (P < 0.05). IHC dampened cumulative NO(2)(-) release during the first 5 min reperfusion from 32 +/- 7 to 14 +/- 2 mumol/g (P < 0.05), but did not alter hyperemic LAD flow (15 +/- 2 vs. 13 +/- 2 ml/g). Thus, IHC suppressed myocardial NOS activity, eNOS content, and excessive NO formation upon reperfusion without compromising reactive hyperemia. Attenuation of the NOS/NO system may contribute to IHC-induced protection of myocardium from ischemia-reperfusion injury. PMID:18408142

Ryou, Myoung-Gwi; Sun, Jie; Oguayo, Kevin N; Manukhina, Eugenia B; Downey, H Fred; Mallet, Robert T

2008-06-01

258

Impact of metabolic syndrome in acute myocardial infarction at hospital.  

PubMed

The study was aimed to find out the impact of metabolic syndrome in patients with acute myocardial infarction during hospital stay. This prospective study was carried out in coronary care unit, Mymensingh Medical College Hospital from August 2009 to May 2010. Patients were followed up for minimum 3 days to maximum 6 days after admission. Variables of this study were age, sex, smoking, anterior AMI, inferior AMI, Non STEMI, hyperglycemia, low high density lipoprotein (HDL), raised blood pressure, high triglyceride (TG), waist circumference, recurrent non fatal MI, heart failure (Killip class), arrhythmia (VT, VF), ejection fraction (EF), family history of cardiovascular (CV) risk factors. Considering inclusion and exclusion criteria total 100 patients were included and divided into two groups, Group A - Acute Myocardial Infarction (AMI) with Metabolic Syndrome (MS) and Group B - Acute Myocardial Infarction (AMI) without Metabolic Syndrome (MS). Investigations included ECG, FBS, fasting lipid profile, cardiac enzyme (troponin I) and echocardiography (2D & M mode). The data were analyzed by computer software SPSS version 12. Chi-square test, t test, ANOVA test was used as test of significance. Among the study population (n=100), female were 12.0%. Mean age of study population was 53.3±10.6 years vs. 47.5±11.3 years. Distribution of metabolic syndrome components in study population, High TG (?150mg/dl) was more prevalent (81.1% vs. 25.8%). Heart failure (Killip class) was significantly more in metabolic syndrome patients than those without metabolic syndrome (46.0 % vs. 20%). LV ejection fraction also lowers in metabolic syndrome patients (46.76±8.34 vs. 50.45±7.50) with MI. Among the components of metabolic syndrome, hyperglycemia had strongest association for development of heart failure (OR 3.05; 95% CI 0.80-12.14). PMID:23715346

Islam, M S; Bari, M A; Paul, G K; Islam, M Z; Rahman, M Z; Hoshneara, M; Karim, M A; Nabi, M N; Pandit, H

2013-04-01

259

Evidence for the existence of a functional helical myocardial band  

NSDL National Science Digital Library

Characterization of local and global contractile activities in the myocardium is essential for a better understanding of cardiac form and function. The spatial distribution of regions that contribute the most to cardiac function plays an important role in defining the pumping parameters of the myocardium like ejection fraction and dynamic aspects such as twisting and untwisting. In general, myocardium shortening, tangent to the wall, and ventricular wall thickening are important parameters that characterize the regional contribution within the myocardium to the global function of the heart. We have calculated these parameters using myocardium displacement fields, which were captured through the displacement-encoding with stimulated echoes (DENSE) MRI technique in three volunteers. High spatial resolution of the acquired data revealed transmural changes of thickening and tangential shortening with high fidelity in beating hearts. By filtering myocardium regions that showed a tangential shortening index of <0.23, we were able to identify the complete or a portion of a macrostructure composed of connected regions in the form of a helical bundle within the left ventricle mass. In this study, we present a representative case that shows the complete morphology of a helical myocardial band as well as two other cases that present ascending and descending portions of the helical myocardial band. Our observation of a helical functional band based on dynamics is in agreement with diffusion tensor MRI observations and gross dissection studies in the arrested heart.

Abbas Nasiraei-Moghaddam (UCLA/California Institute of Technology); Morteza Gharib (California Institute of Technology)

2008-11-07

260

Fabrication of biologically derived injectable materials for myocardial tissue engineering.  

PubMed

This protocol provides methods for the preparation of an injectable extracellular matrix (ECM) gel for myocardial tissue engineering applications. Briefly, decellularized tissue is lyophilized, milled, enzymatically digested, and then brought to physiological pH. The lyophilization removes all water content from the tissue, resulting in dry ECM that can be ground into a fine powder with a small mill. After milling, the ECM powder is digested with pepsin to form an injectable matrix. After adjustment to pH 7.4, the liquid matrix material can be injected into the myocardium. Results of previous characterization assays have shown that matrix gels produced from decellularized pericardial and myocardial tissue retain native ECM components, including diverse proteins, peptides and glycosaminoglycans. Given the use of this material for tissue engineering, in vivo characterization is especially useful; here, a method for performing an intramural injection into the left ventricular (LV) free wall is presented as a means of analyzing the host response to the matrix gel in a small animal model. Access to the chest cavity is gained through the diaphragm and the injection is made slightly above the apex in the LV free wall. The biologically derived scaffold can be visualized by biotin-labeling before injection and then staining tissue sections with a horse radish peroxidase-conjugated neutravidin and visualizing via diaminobenzidine (DAB) staining. Analysis of the injection region can also be done with histological and immunohistochemical staining. In this way, the previously examined pericardial and myocardial matrix gels were shown to form fibrous, porous networks and promote vessel formation within the injection region. PMID:22158083

Seif-Naraghi, Sonya; Singelyn, Jennifer; Dequach, Jessica; Schup-Magoffin, Pamela; Christman, Karen

2010-01-01

261

Pseudoaneurysm of the anterior tibial artery: A rare complication of proximal tibial steinman pin insertion  

PubMed Central

An anterior tibial artery pseudoaneurysm is a rare and unexpected complication of Steinmann pin insertion. We describe the case of an 18-year-old boy, who sustained such an injury to the anterior tibial artery during this procedure. Diagnosis was confirmed on a magnetic resonance (MR) angiogram. Aneurysmal sac excision with lateral repair of the vessel wall was performed. Postoperatively, a good flow was documented on a follow-up MR angiogram. This case highlights a major and unexpected complication of a so-called minor procedure. Too posterior a pin placement in the proximal tibia should be avoided to prevent such injuries. PMID:21430875

Suri, Tarun; Dabas, Vineet; Sural, Sumit; Dhal, Anil

2011-01-01

262

Experimental and Numerical Analysis of Screw Fixation in Anterior Cruciate Ligament Reconstruction  

NASA Astrophysics Data System (ADS)

This paper reports the results of an experimental and finite element analysis of tibial screw fixation in anterior cruciate ligament (ACL) reconstruction. The mechanical properties of the bone and tendon graft are obtained from experiments using porcine bone and bovine tendon. The results of the numerical study are compared with those from mechanical testing. Analysis shows that the model may be used to establish the optimum placement of the tunnel in anterior cruciate ligament reconstruction by predicting mechanical parameters such as stress, strain and displacement at regions in the tunnel wall.

Chizari, Mahmoud; Wang, Bin; Snow, Martyn; Barrett, Mel

2008-09-01

263

Mild toxic anterior segment syndrome mimicking delayed onset toxic anterior segment syndrome after cataract surgery  

PubMed Central

Toxic anterior segment syndrome (TASS) is an acute sterile postoperative anterior segment inflammation that may occur after anterior segment surgery. I report herein a case that developed mild TASS in one eye after bilateral uneventful cataract surgery, which was masked during early postoperative period under steroid eye drop and mimicking delayed onset TASS after switching to weaker steroid eye drop. PMID:25230969

Lee, Su-Na

2014-01-01

264

LV wall segmentation using the variational level set method (LSM) with additional shape constraint for oedema quantification  

NASA Astrophysics Data System (ADS)

In this paper an automatic algorithm for the left ventricle (LV) wall segmentation and oedema quantification from T2-weighted cardiac magnetic resonance (CMR) images is presented. The extent of myocardial oedema delineates the ischaemic area-at-risk (AAR) after myocardial infarction (MI). Since AAR can be used to estimate the amount of salvageable myocardial post-MI, oedema imaging has potential clinical utility in the management of acute MI patients. This paper presents a new scheme based on the variational level set method (LSM) with additional shape constraint for the segmentation of T2-weighted CMR image. In our approach, shape information of the myocardial wall is utilized to introduce a shape feature of the myocardial wall into the variational level set formulation. The performance of the method is tested using real CMR images (12 patients) and the results of the automatic system are compared to manual segmentation. The mean perpendicular distances between the automatic and manual LV wall boundaries are in the range of 1-2 mm. Bland-Altman analysis on LV wall area indicates there is no consistent bias as a function of LV wall area, with a mean bias of -121 mm2 between individual investigator one (IV1) and LSM, and -122 mm2 between individual investigator two (IV2) and LSM when compared to two investigators. Furthermore, the oedema quantification demonstrates good correlation when compared to an expert with an average error of 9.3% for 69 slices of short axis CMR image from 12 patients.

Kadir, K.; Gao, H.; Payne, A.; Soraghan, J.; Berry, C.

2012-10-01

265

Myocardial bridging analysis by coronary computed tomographic angiography in a Saudi population  

PubMed Central

AIM: To assess the incidence, location, morphology and clinical association of myocardial bridging in a Saudi population using coronary computed tomographic angiography (CCTA). METHODS: A total of 350 CCTA of Saudi patients were included in this study (236 men, 114 women) with a mean age of 56.3 years. All patients were examined for appropriateness criteria of CCTA indications (typical chest pain, recent onset cardiomyopathy, left bundle branch block, etc.). The scans were retrospectively reviewed for the presence of myocardial bridging and any other pathological association. RESULTS: Myocardial bridging was found in 89 of 350 (22.5%) patients. Most of the intramuscular segments were of the superficial type and found in the mid left anterior descending (LAD) (24.6%), followed by distal LAD (3.7%), diagonal branches (2%), ramus intermedius artery (1.4%) and obtuse marginal artery (0.8%). No myocardial bridging was detected in the right coronary or circumflex arteries. No significant differences were found between males and females (P = 0.14). Coronary artery atherosclerosis was found in 51 of 89 (57.3%) patients with MB. Atherosclerotic plaques were not detected in the intramuscular or distal segment of bridging arteries. Dynamic compression was observed in 35 (94.5%) patients with full encasement. No evidence of myocardial hypoperfusion was found in the territories supplied by the bridging arteries. CONCLUSION: CCTA is excellent in analyzing myocardial bridging in a Saudi population and the results are comparable to other populations. However, finding the real incidence may need a large multicenter study. PMID:24340142

Donkol, Ragab Hani; Saad, Zizi

2013-01-01

266

Percutaneous electrocatheter technique for on-line detection of healed transmural myocardial infarction.  

PubMed

Healed myocardial infarction has been recognized by its particular tissue electrical impedance spectrum measured with intramural needle electrodes in animal models. The aim of this study was to develop a percutaneous approach for in vivo recognition of areas of healed myocardial infarction by measuring myocardial electrical impedance with an intracavitary contact electrocatheter. Electrical impedance (resistance and phase angle) of normal myocardium and of a 2-month-old anterior transmural infarction were measured in nine chloralose anesthetized pigs by applying alternating currents from 1 kHz to 1 MHZ between a bipolar intracavitary catheter and a reference electrode placed on the epicardium (group I, n = 4) or on the precordium (group II, n = 5). Resistance of the infarcted myocardium was lower than that of healthy tissue at all current frequencies (ANOVA, P < 0.001) (i.e., at 1 kHz: 15 +/- 4 omega vs 50 +/- 19 omega in group I, and 64 +/- 13 omega vs 76 +/- 13 omega in group II). Phase angle at 316 kHz best differentiated transmural infarction from normal tissue (group I: -2.5 +/- 1.9 degrees vs -14.8 +/- 4.6 degrees, P < 0.001; group II: +0.7 +/- 1.0 degrees vs -2.7 +/- 1.4 degrees, P < 0.001). This study shows that analysis of myocardial impedance spectrum using a percutaneous intracavitary contact catheter approach permits on-line recognition of areas of healed transmural myocardial infarction. This technique may be useful to optimize clinical application of energy sources (i.e., radiofrequency ablation, laser myocardial revascularization). PMID:10962753

Warren, M; Bragós, R; Casas, O; Rodríguez-Sinovas, A; Rosell, J; Anivarro, I; Cinca, J

2000-08-01

267

The role of dietary fatty acids in predicting myocardial structure in fat-fed rats  

PubMed Central

Background Obesity increases the risk for development of cardiomyopathy in the absence of hypertension, diabetes or myocardial ischemia. Not all obese individuals, however, progress to heart failure. Indeed, obesity may provide protection from cardiovascular mortality in some populations. The fatty acid milieu, modulated by diet, may modify obesity-induced myocardial structure and function, lending partial explanation for the array of cardiomyopathic phenotypy in obese individuals. Methods Adult male Sprague-Dawley rats were fed 1 of the following 4 diets for 32 weeks: control (CON); 50% saturated fat (SAT); 40% saturated fat + 10% linoleic acid (SAT+LA); 40% saturated fat + 10% ?-linolenic acid (SAT+ALA). Serum leptin, insulin, glucose, free fatty acids and triglycerides were quantitated. In vivo cardiovascular outcomes included blood pressure, heart rate and echocardiographic measurements of structure and function. The rats were sacrificed and myocardium was processed for fatty acid analysis (TLC-GC), and evaluation of potential modifiers of myocardial structure including collagen (Masson's trichrome, hydroxyproline quantitation), lipid (Oil Red O, triglyceride quantitation) and myocyte cross sectional area. Results Rats fed SAT+LA and SAT+ALA diets had greater cranial LV wall thickness compared to rats fed CON and SAT diets, in the absence of hypertension or apparent insulin resistance. Treatment was not associated with changes in myocardial function. Myocardial collagen and triglycerides were similar among treatment groups; however, rats fed the high-fat diets, regardless of composition, demonstrated increased myocyte cross sectional area. Conclusions Under conditions of high-fat feeding, replacement of 10% saturated fat with either LA or ALA is associated with thickening of the cranial LV wall, but without concomitant functional changes. Increased myocyte size appears to be a more likely contributor to early LV thickening in response to high-fat feeding. These findings suggest that myocyte hypertrophy may be an early change leading to gross LV hypertrophy in the hearts of "healthy" obese rats, in the absence of hypertension, diabetes and myocardial ischemia. PMID:21649916

2011-01-01

268

Correlates of knee anterior laxity in sportswomen.  

PubMed

The purpose of this study was to evaluate whether any of the following factors are related to knee anterior laxity in healthy sportswomen: anthropometric characteristics, lower limb alignment characteristics, hormone-related factors and sport history. Six hundred and sixteen sportswomen were tested in the pre-season. The data have been analysed using linear regression for possible association of knee anterior laxity with other variables. Univariate linear regression indicated a positive association of knee anterior laxity with knee extension and navicular drop and a negative association with body height. Multivariate linear regression analysis showed statistically significant associations between knee anterior laxity and the combination of passive knee extension and the chosen sport (R(2)=0.089; p<0.05). The combination of passive knee extension and sport type was found to be related to the amount of knee anterior laxity, although the association was weak with this combination of factors able to explain only about 9% of the variability in laxity. Knowing which factors influence the amount of knee anterior laxity will help us to better interpret the results of knee anterior laxity testing and help us to understand the possible role of knee anterior laxity as a risk factor for knee injury. PMID:19423353

Vauhnik, Renata; Morrissey, Matthew C; Rutherford, Olga M; Turk, Zmago; Pilih, Iztok A; Perme, Maja Pohar

2009-12-01

269

Anterior pericardial tracheoplasty for congenital tracheal stenosis.  

PubMed

Congenital tracheal stenosis may be a life-threatening anomaly not relieved by airway intubation. Over the past 7 years, anterior pericardial tracheoplasty has been used at our institution for treatment of congenital long-segment tracheal stenosis in infants with impeding airway obstruction. Case histories of eight patients undergoing nine anterior pericardial tracheoplasties have been reviewed to assess this technique. Of these patients, six have required preoperative tracheal intubation before repair to maintain ventilation. The surgical technique of anterior pericardial tracheoplasty includes a median sternotomy approach with partial normothermic cardiopulmonary bypass. An anterior tracheotomy through all hypoplastic rings allows enlargement with autologous pericardium to 1.5 times the predicted normal diameter. After insertion, the pericardium and hypoplastic tracheal cartilages are suspended to surrounding mediastinal structures, which prevents airway collapse. Seven of eight infants have survived without tracheoplasty dehiscence or wound infections. Five were ultimately extubated and are currently free of symptoms from 6 months to 5 years after anterior pericardial tracheoplasty. The other two survivors had residual stenosis as a result of complications of prior tracheostomy. One of these patients has undergone a successful second anterior pericardial tracheoplasty and is currently extubated and well. The other is palliated at 6 months with a tracheostomy awaiting a second anterior pericardial tracheoplasty. Our review of anterior pericardial tracheoplasty has demonstrated the safety, utility, and at least medium-term benefit of this procedure in infants of any age and weight. PMID:1943189

Heimansohn, D A; Kesler, K A; Turrentine, M W; Mahomed, Y; Means, L; Matt, B; Weisberger, E; Brown, J W

1991-11-01

270

Acute hemiconcern: a right anterior parietotemporal syndrome  

Microsoft Academic Search

Three patients developed a striking visual and motor behaviour in the acute phase of a stroke involving the territory of the right anterior parietal artery (postcentral gyrus, parts or upper and middle temporal gyri, anterior part of inferior parietal gyrus, and supramarginal gyrus). The patients concentrated on the left side of their bodies, looking at it for long periods and

J Bogousslavsky; E Kumral; F Regli; G Assal; J Ghika

1995-01-01

271

Experiments on anterior regeneration in Eurythoe complanata (\\  

Microsoft Academic Search

In the polychaete Eurythoe complanata (Amphinomidae) regeneration of the nervous system has been monitored after amputation of anterior segments and after amputation plus extirpation of one to a few anterior ganglia of the ventral nerve cord. The serotonergic subunit of the nervous system was visualized with an antibody directed against the bioamine 5-HT. Cell proliferation could be demonstrated by incorporation

Monika C. M. Müller; Andreas Berenzen; Wilfried Westheide

2003-01-01

272

Microsurgical anatomy of the anterior choroidal artery  

Microsoft Academic Search

Summary In this study, the authors present the results of 50 dissections of the anterior choroidal a. in man. Fifty cerebral hemispheres were prepared with the classic techniques of preservation and vascular injection. An ectopic origin was observed in 4% of cases. The intracisternal segment of the anterior choroidal a. forms a neurovascular bundle with the optic tract and basal

X Morandi; G Brassier; P Darnault; Ph Mercier; JM Scarabin; JM Duval

1996-01-01

273

Apyrase treatment of myocardial infarction according to a clinically applicable protocol fails to reduce myocardial injury in a porcine model  

PubMed Central

Background Ectonucleotidase dependent adenosine generation has been implicated in preconditioning related cardioprotection against ischemia-reperfusion injury, and treatment with a soluble ectonucleotidase has been shown to reduce myocardial infarct size (IS) when applied prior to induction of ischemia. However, ectonucleotidase treatment according to a clinically applicable protocol, with administration only after induction of ischemia, has not previously been evaluated. We therefore investigated if treatment with the ectonucleotidase apyrase, according to a clinically applicable protocol, would reduce IS and microvascular obstruction (MO) in a large animal model. Methods A percutaneous coronary intervention balloon was inflated in the left anterior descending artery for 40 min, in 16 anesthetized pigs (40-50 kg). The pigs were randomized to 40 min of 1 ml/min intracoronary infusion of apyrase (10 U/ml, n = 8) or saline (0.9 mg/ml, n = 8), twenty minutes after balloon inflation. Area at risk (AAR) was evaluated by ex vivo SPECT. IS and MO were evaluated by ex vivo MRI. Results No differences were observed between the apyrase group and saline group with respect to IS/AAR (75.7 ± 4.2% vs 69.4 ± 5.0%, p = NS) or MO (10.7 ± 4.8% vs 11.4 ± 4.8%, p = NS), but apyrase prolonged the post-ischemic reactive hyperemia. Conclusion Apyrase treatment according to a clinically applicable protocol, with administration of apyrase after induction of ischemia, does not reduce myocardial infarct size or microvascular obstruction. PMID:20047685

2010-01-01

274

Eighteen months of anterior chamber inflammation.  

PubMed

A 60-year-old Chinese patient was seen multiple times in the ophthalmology outpatient department due to persistent anterior-chamber inflammation and raised intraocular pressure. The patient was being treated with topical corticosteroids and oral acyclovir. Signs of corneal endotheliitis were observed in subsequent follow-ups. A clinical diagnosis could be made on slit-lamp examination, but aetiology could not be specified. An anterior-chamber diagnostic tap performed 18 months after the initial presentation revealed cytomegalovirus (CMV). Prompt response was noted with oral valganciclovir treatment. Our case highlights the importance of performing anterior-chamber tap in cases with persistent anterior-chamber inflammation. There was a long interval between the presentation and diagnosis mainly due to the absence of any concurrent ocular signs. An anterior-chamber tap was delayed until the ocular signs were suggestive of CMV endotheliitis. Timely diagnosis in such cases can improve the outcome as well as the prognosis. PMID:23997088

Jhanji, Vishal; Kwok, Rachel; Young, Alvin L

2013-01-01

275

Anterior Segment Imaging in Combat Ocular Trauma  

PubMed Central

Purpose. To evaluate the use of ocular imaging to enhance management and diagnosis of war-related anterior segment ocular injuries. Methods. This study was a prospective observational case series from an ongoing IRB-approved combat ocular trauma tracking study. Subjects with anterior segment ocular injury were imaged, when possible, using anterior segment optical coherence tomography (AS-OCT), confocal microscopy (CM), and slit lamp biomicroscopy. Results. Images captured from participants with combat ocular trauma on different systems provided comprehensive and alternate views of anterior segment injury to investigators. Conclusion. In combat-related trauma of the anterior segment, adjunct image acquisition enhances slit lamp examination and enables real time In vivo observation of the cornea facilitating injury characterization, progression, and management. PMID:24191191

Ryan, Denise S.; Sia, Rose K.; Colyer, Marcus; Stutzman, Richard D.; Wroblewski, Keith J.; Mines, Michael J.; Bower, Kraig S.

2013-01-01

276

Collateral circulation as a marker of the presence of viable myocardium in patients with recent myocardial infarction  

SciTech Connect

The relationship between the presence of viable myocardium and the extent of coronary collateral circulation to the infarct area was evaluated in 20 patients with a recent anterior myocardial infarction who had complete obstruction of the left anterior descending coronary artery. The viability of myocardial tissue was assessed by exercise thallium-201 myocardial scintigraphy, and the collateral circulation was angiographically evaluated by means of a collateral index ranging from 0 to 3. Patients were divided into two groups according to the presence (group 1, n = 10) or absence (group 2, n = 10) of viable myocardium in the perfusion territory of the infarct-related artery. The collateral index in group 1 was 2.5 {plus minus} 0.5 (SD), which was significantly higher than the 0.7 {plus minus} 0.8 in group 2. These findings indicate that the presence of ischemic but viable myocardium is intimately related to the development of collateral circulation in patients with myocardial infarction, and the existence of well-developed collateral channels predicts the presence of viable myocardium in the infarct area.

Fujita, M.; Ohno, A.; Wada, O.; Miwa, K.; Nozawa, T.; Yamanishi, K.; Sasayama, S. (Toyama Medical and Pharmaceutical Univ. (Japan))

1991-08-01

277

Myocardial contrast echocardiography to assess perfusion in a mouse model of ischemia/reperfusion injury  

NASA Astrophysics Data System (ADS)

Noninvasive approaches for measuring anatomical and physiological changes resulting from myocardial ischemia / reperfusion injury in the mouse heart have significant value since the mouse provides a practical, low-cost model for modeling human heart disease. In this work, perfusion was assessed before, during and after an induced closed- chest, coronary ischemic event. Ultrasound contrast agent, similar to MP1950, in a saline suspension, was injected via cannulated carotid artery as a bolus and imaged using a Siemens Sequoia 512 scanner and a 15L8 intraoperative transducer operating in second harmonic imaging mode. Image sequences were transferred from the scanner to a PC for analysis. Regions of interest were defined in septal and anterior segments of the myocardium. During the ischemic event, when perfusion was diminished in the anterior segment, mean video intensity in the affected segment was reduced by one half. Furthermore, following reperfusion, hyperemia (enhanced blood flow) was observed in the anterior segment. Specifically, the mean video intensity in the affected segment was increased by approximately 50% over the original baseline level prior to ischemia. Following the approach of Kaul et al., [1], gamma variate curves were fitted to the time varying level of mean video intensity. This foundation suggests the possibility of quantifying myocardial blood flow in ischemic regions of a mouse heart using automated analysis of contrast image data sets. An improved approach to perfusion assessment using the destruction-reperfusion approach [2] is also presented.

Hossack, John A.; Li, Yinbo; Christensen, Jonathan P.; Yang, Zequan; French, Brent A.

2004-04-01

278

Chest wall reconstruction in Marfan syndrome following aortic root replacement.  

PubMed

Chest wall and spine deformities are common in Marfan syndrome, and often coexist with cardiac defects. Surgery is often needed to both the aortic root and the anterior chest wall, and early spinal surgery is not uncommon. We describe a case of severe thoracic cage deformity with aortic root dilatation, which was managed by a staged approach, with a very good final result. PMID:24887858

Bezuska, Laurynas; Mussa, Shaffi; Muthialu, Nagarajan

2014-09-01

279

Evaluation of regional myocardial nutrient perfusion following selective retrograde arterialization of the coronary vein.  

PubMed

The effects of selective coronary vein occlusion (SCVO) and selective retrograde arterialization of the coronary vein (SRACV) on nutritional myocardial blood flow was evaluated in 10 dogs with radioactive microspheres. SRACV was performed with a shunt interposed between the aorta and the great cardiac vein (GCV). Following ligation of the GCV, measurements were performed before and after ligation of the middle portion of the left anterior descending coronary artery (LAD) and then after 15 and 30 minutes of SRACV. The myocardium was divided into three regions: circumflex coronary artery (served as control), high LAD (proximal to arterial occlusion; supplied by both SRACV and coronary flow), and low LAD (distal to arterial occlusion; supplied by SRACV alone). SCVO decreased mean myocardial blood flow with increased distribution to the endocardium. SRACV to normally perfused myocardium did not significantly change myocardial blood flow; however, SRACV to acutely ischemic myocardium restored less than 50% of the decrease in myocardial blood flow. SRACV does not appear to greatly enhance blood flow to ischemic areas of the myocardium and may significantly reduce flow on the basis of venous occlusion alone. PMID:637609

Rhodes, G R; Syracuse, D C; McIntosh, C L

1978-04-01

280

Comparison of radionuclide and enzymatic estimate of infarct size in patients with acute myocardial infarction  

SciTech Connect

A comparison was made of the estimated size of the myocardial infarction occurring in 26 patients with a first infarction using creatine kinase (CK) enzyme release between radionuclide gated blood pool measurement of total and regional ventricular function and thallium-201 scintigraphic measurement of myocardial perfusion defects. Creatine kinase estimates of infarct size (enzymatic infarct size) correlated closely with the percent of abnormal contracting regions, left ventricular ejection fraction and thallium-201 estimates of percent of abnormal perfusion area (r . 0.78, 0.69 and 0.74, respectively, p less than 0.01). A close correlation also existed between percent abnormal perfusion area and percent of abnormal contracting regions (r . 0.81, p less than 0.01) and left ventricular ejection fraction (r . 0.69, p less than 0.01). Enzymatic infarct size was larger in anterior (116 +/- 37 CK-g-Eq) than inferior (52 +/- 29 CK-g-Eq) myocardial infarction (p less than 0.01) and was associated with significantly more left ventricular functional impairment as determined by left ventricular ejection fraction (33 +/- 7 versus 60 +/- 10%) (p less than 0.01) and percent abnormal perfusion area (58 +/- 14 versus 13 +/- 12) (p less than 0.01). No significant correlation was observed between enzymatic infarct size and right ventricular ejection fraction. These different methods of estimating infarct size correlated closely with each other in these patients with a first uncomplicated myocardial infarction.

Hirsowitz, G.S.; Lakier, J.B.; Marks, D.S.; Lee, T.G.; Goldberg, A.D.; Goldstein, S.

1983-06-01

281

Acute myocardial infarct imaging with indium-111-labeled monoclonal antimyosin Fab  

SciTech Connect

Indium-111 monoclonal antimyosin Fab scintigraphy was used to detect myocardial necrosis in 52 of 54 patients (96.3%) with acute myocardial infarction. Infarcts were visualized when coronary arteries were persistently occluded (n = 10), became patent after thrombolysis (n = 33), or became patent after spontaneous reperfusion (n = 7). Posteroinferolateral visualizations were obtained in two patients with clinical and enzymatic evidence of infarction but normal electrocardiograms. Of the two patients in whom no infarcts were visualized, one had an anterior myocardial infarct. This patient underwent successful thrombolytic therapy, with attendant minimization of creatine kinase release. The other patient had a small, nonreperfused inferior myocardial infarct. Five patients with a history of remote infarction and acute necrosis showed antimyosin uptake only in regions concordant with the acute episodes of infarction, and radiolabeled antimyosin Fab localized in neither old infarcts nor normal, noninfarcted myocardium. Antimyosin Fab scintigraphy, thus, appears to be a highly specific means of delineating necrotic myocardium, at least in this limited and selected group of patients.

Khaw, B.A.; Yasuda, T.; Gold, H.K.; Leinbach, R.C.; Johns, J.A.; Kanke, M.; Barlai-Kovach, M.; Strauss, H.W.; Haber, E.

1987-11-01

282

Effects of Doxycycline on Cx43 Distribution and Cardiac Arrhythmia Susceptibility of Rats after Myocardial Infarction  

PubMed Central

This study aims to observe the effects of doxycycline (DOX) on gap junction remodeling after MI and the susceptibility of rats to cardiac arrhythmia. The proximal left anterior descending coronary artery of rats was ligated to establish a myocardial infarction animal model. DOX, methylprednisolone (MP), or vehicle was intraperitoneally injected into the animals for two weeks. Then, the heart size and heart function of all animals were determined through echocardiography. The experimental animals were sacrificed after the electrophysiologic study. Myocardial tissues were sampled to analyze the distribution of Cx43 using immunofluorescence; the Cx43 content was analyzed using western blot analysis; and the MMP-2 and MMP-9 activity in the myocardium was analyzed using gelatin zymography. The distribution of Cx43 in the border of the infarcted myocardia in the MI and MP groups was clearly disrupted and the Cx43 content was significantly reduced. In addition, the distribution of Cx43 in the border of the infarct in the DOX group was relatively regular, whereas two weeks of DOX treatment significantly inhibited MMP activity. Meanwhile, the induction rate of arrhythmia in the rats after DOX treatment was lower than those in the MI and MP groups. The results show that DOX treatment after myocardial infarction improves gap junction remodeling in the myocardial tissue near the infarcted area by inhibiting MMP activity and reducing susceptibility to cardiac arrhythmia.

Fana, Xi-zhen; Zhu, Hong-jun; Wu, Xu; Yan, Ji; Xu, Jian; Wang, De-guo

2014-01-01

283

Imaging and modeling of myocardial metabolism.  

PubMed

Current imaging methods have focused on evaluation of myocardial anatomy and function. However, since myocardial metabolism and function are interrelated, metabolic myocardial imaging techniques, such as positron emission tomography, single photon emission tomography, and magnetic resonance spectroscopy present novel opportunities for probing myocardial pathology and developing new therapeutic approaches. Potential clinical applications of metabolic imaging include hypertensive and ischemic heart disease, heart failure, cardiac transplantation, as well as cardiomyopathies. Furthermore, response to therapeutic intervention can be monitored using metabolic imaging. Analysis of metabolic data in the past has been limited, focusing primarily on isolated metabolites. Models of myocardial metabolism, however, such as the oxygen transport and cellular energetics model and constraint-based metabolic network modeling, offer opportunities for evaluation interactions between greater numbers of metabolites in the heart. In this review, the roles of metabolic myocardial imaging and analysis of metabolic data using modeling methods for expanding our understanding of cardiac pathology are discussed. PMID:20559785

Obrzut, Sebastian; Jamshidi, Neema; Karimi, Afshin; Birgersdotter-Green, Ulrika; Hoh, Carl

2010-08-01

284

Chronic right ventricular pressure overload results in a hyperplastic rather than a hypertrophic myocardial response.  

PubMed

Myocardial hyperplasia is generally considered to occur only during fetal development. However, recent evidence suggests that this type of response may also be triggered by cardiac overload after birth. In congenital heart disease, loading conditions are frequently abnormal, thereby affecting ventricular function. We hypothesized that chronic right ventricular pressure overload imposed on neonatal hearts initiates a hyperplastic response in the right ventricular myocardium. To test this, young lambs (aged 2-3 weeks) underwent adjustable pulmonary artery banding to obtain peak right ventricular pressures equal to left ventricular pressures for 8 weeks. Transmural cardiac tissue samples from the right and left ventricles of five banded and five age-matched control animals were studied. We found that chronic right ventricular pressure overload resulted in a twofold increase in right-to-left ventricle wall thickness ratio. Morphometric right ventricular myocardial tissue analysis revealed no changes in tissue composition between the two groups; nor were right ventricular myocyte dimensions, relative number of binucleated myocytes, or myocardial DNA concentration significantly different from control values. In chronic pressure overloaded right ventricular myocardium, significantly (P < 0.01) more myocyte nuclei were positive for the proliferation marker proliferating cellular nuclear antigen than in control right ventricular myocardium. Chronic right ventricular pressure overload applied in neonatal sheep hearts results in a significant increase in right ventricular free wall thickness which is primarily the result of a hyperplastic myocardial response. PMID:18248360

Leeuwenburgh, Boudewijn P J; Helbing, Willem A; Wenink, Arnold C G; Steendijk, Paul; de Jong, Roos; Dreef, Enno J; Gittenberger-de Groot, Adriana C; Baan, Jan; van der Laarse, Arnoud

2008-03-01

285

Monocyte Chemoattractant Proteins Mediate Myocardial Microvascular Dysfunction in Swine Renovascular Hypertension  

PubMed Central

Background Monocyte chemoattractant proteins (MCPs) play an important role in mediating inflammatory processes. Hypertension (HTN) is associated with inflammation as well as impaired cardiac microcirculatory function and structure, but the contribution of MCPs to these alterations remained unclear. This study tested the hypothesis that MCPs regulate cardiac microvascular function and structure in an experimental HTN. Methods and Results Pigs (n=6/group) were studied after 10 weeks of normal, renovascular HTN, or renovascular HTN+ bindarit (MCPs inhibitor, 50 mg/kg/day PO). Left ventricular (LV) function, myocardial microvascular permeability, and fractional vascular volume were assessed by fast computed tomography before and after adenosine infusion (400 ?g/kg/min). Myocardial fibrosis, inflammation, and microvascular remodeling were determined ex-vivo. Hypertension was not altered by bindarit, but LV hypertrophy and diastolic function were improved. In response to adenosine, myocardial microvascular permeability increased in HTN (from 0.0083±0.0009 to 0.0103±0.0011 AU, p=0.038 vs. baseline) and fractional vascular volume decreased, while both remained unchanged in normal and HTN+bindarit pigs. HTN upregulated endothelin-1 expression, myocardial inflammation and microvascular wall thickening, which were inhibited by bindarit. Conclusions MCPs partly mediate myocardial inflammation, fibrosis, vascular remodeling, and impaired vascular integrity induced by hypertension. Inhibition of MCPs could potentially be a therapeutic target in hypertensive cardiomyopathy. PMID:19628782

Lin, Jing; Zhu, Xiangyang; Chade, Alejandro R.; Jordan, Kyra L.; Lavi, Ronit; Daghini, Elena; Gibson, Matthew E.; Guglielmotti, Angelo; Lerman, Amir; Lerman, Lilach O.

2009-01-01

286

A young patient with coronary artery anomaly, whose left anterior descending artery originated from the pulmonary artery, underwent cardiac arrest.  

PubMed

A rare congenital anomaly of the coronary arteries, in which the left coronary arterial system starts from the arteria pulmonalis, is known as Bland-White-Garland (BWG) syndrome. Isolated left anterior descending (LAD) or circumflex (Cx) arteries originating from the pulmonary artery are even more rare. These anomalies may cause myocardial ischaemia, myocardial infarction, arrhythmia and sudden death. Even if the patient is asymptomatic, he/she should undergo corrective surgery. Here we present the case of an 18-year-old male who survived sudden cardiac arrest during exercise. We identified intra-myocardial blood flow from transthoracic echocardiography, and performed coronary and computed tomographic (CT) angiography, which showed that all the coronary arteries were ectatic and curly and there were disseminated collaterals among the coronary arteries. We diagnosed 'anomalous left coronary artery from the pulmonary artery' (ALCAPA) syndrome, as additionally, the LAD originated from the pulmonary artery. We treated the patient with a left internal mammarian artery - left anterior descending artery (LIMA-LAD) graft. PMID:23044527

Sahin, Tayfun; Bozyel, Serdar; Acar, Eser; Bildirici, Ulas; Yavuz, Sadan; Baris, Ozgur; Ural, Ertan; Ural, Dilek

2012-09-01

287

Effects of exercise training on cardiac function and myocardial remodeling in post myocardial infarction rats  

PubMed Central

Objective To test the hypothesis that early exercise training after myocardial infarction (MI) could preserve cardiac function, alleviate left ventricular (LV) remodeling and induce a protective effect on morphology. Methods Male Sprague-Dawley rats underwent coronary ligation or sham operation, and were assigned to 3 groups: Sham, sedentary MI (SedMI), and exercise MI (ExMI). We measured the changes in collagen volume fraction, matrix metalloproteinase (MMP) 1, tissue inhibitor matrix metalloproteinase 1 (TIMP-1), angiotensin II receptor type 1 (AT1), and angiotensin converting enzyme (ACE) at gene and protein levels after 8 weeks of exercise training. Cardiac functions were determined by echocardiographic and hemodynamic measurements. Results Early exercise training after MI had no effect on LV wall thinning. Cardiac function was significantly preserved in the ExMI group in comparison to the SedMI group. The collagen volume fraction in the ExMI group was significantly lower than in the SedMI group. Compared to the SedMI group, the ExMI group showed a markedly decrease at both the gene and protein levels in TIMP-1 (P<0.05). No significant differences were found in MMP-1 among the three groups. MMP-1/TIMP-1 ratio in the ExMI group was significantly higher than in the SedMI group. In addition, the expression of AT1 protein in the ExMI group was significantly lower than in the SedMI group. Furthermore, both ACE mRNA expression and ACE binding in the ExMI group are significantly decreased compared to the SedMI group. Conclusions Our results suggest that early exercise training after MI reduces TIMP-1 expression, improves the balance between MMPs and TIMPs, and mitigates the expressions of ACE and AT1 receptor. These improvements, in turn, attenuate myocardial fibrosis and preserve post-MI cardiac function. PMID:17980387

Xu, Xiaohua; Wan, Wenhan; Powers, Anthony S.; Li, Ji; Ji, Lisa; Lao, Shunhua; Wilson, Bryan; Erikson, John M.; Zhang, John Q.

2008-01-01

288

Accumulation of Iron in a Model of Myocardial Infarction and Its Cell Toxicity in Cardiomyocytes  

PubMed Central

Introduction: Despite advancements in medicine leading to a marked decline in mortality due to acute myocardial infarction (MI), mortality due to post-MI heart failure (HF) remains high. Left ventricular (LV) remodeling is important in the pathogenesis of HF following MI. Previous reports investigating iron overload in anemia and chronic liver cirrhosis suggest that excess iron exhibits cell toxicity in multiple organ systems. During acute MI, ischemia/reperfusion (I/R) injury caused by temporary coronary ischemia results in massive necrosis followed by fibrosis. Previous reports studying tissue injury demonstrated that iron accumulation suppresses wound healing and exacerbates tissue injury in other organs. However, the role of iron in scar formation and LV remodeling is not well characterized. Methods: To address this, we investigated iron, transferrin, and fibrosis in heart tissue sections after I/R injury, and potential cytotoxic effects of iron in the form of FeCl3 on HL-1 and H9C2 cardiomyocytes. Mice underwent surgical I/R injury using left anterior descending coronary ligation to induce 30-minute transient ischemia. The hearts were harvested 1 week later and prepared for histological assays. Results: Masson's trichrome staining revealed fibrosis from the anterior to posterior wall in the mid-myocardium. Perl's iron staining revealed non-transferrin bound iron localized in scar tissue at anterior and posterior aspects of the heart. Immunohistochemistry found ferritin localization to areas of fibrosis, specifically in the extracellular fluid of mid-myocardium and intracellular fluid of fibroblasts and surrounding cardiomyocytes. While iron was undetectable in iron stains of sham operated mice, more than 50 cells were positive with the iron stain in I/R group. Image J (NIH) showed increased anti-ferritin staining in the I/R group compared to sham controls (more than a four-fold increase). To further investigate this, HL-1 and H9C2 cardiomyocytes were cultured with doses of 1 µM to 1 mM FeCl3 for 24 hours, and cell death was analyzed with Live/Dead Cell Viability Assay (Invitrogen). Treatment greater than 100 µM decreased cell viability, and significant cell death (n=6, P<.05) was observed in cardiomyocytes exposed to 50 µM FeCl3 or more, and that excess iron leads to cell death. Conclusions: These results suggest that iron accumulation may play a role in cardiac cell death and fibrosis in ventricular myofiber remodeling after I/R injury. Taken together, excess iron in MI may induce cell death, leading to LV remodeling following I/R injury. Understanding the role of iron accumulation in the heart could develop new therapeutic strategies for treating multiple heart diseases including HF.

Higa, Jason K; Matsui, Takashi

2014-01-01

289

Myocardial injury in acute stroke  

Microsoft Academic Search

Introduction: Acute cerebrovascular insults can induce a variety of cardiac changes. We sought to describe the findings in a cohort of\\u000a patients who had an acute stroke in whom Troponin I (TI) was sampled to determine the presence of associated myocardial damage.\\u000a \\u000a \\u000a Materials and Methods: This is a retrospective case series study. The investigators identified all patients who had an

Julio A. Chalela; Mustapha A. Ezzeddine; Lisa Davis; Steven Warach

2004-01-01

290

Myocardialization of the cardiac outflow tract.  

PubMed

During development, the single-circuited cardiac tube transforms into a double-circuited four-chambered heart by a complex process of remodeling, differential growth, and septation. In this process the endocardial cushion tissues of the atrioventricular junction and outflow tract (OFT) play a crucial role as they contribute to the mesenchymal components of the developing septa and valves in the developing heart. After fusion, the endocardial ridges in the proximal portion of the OFT initially form a mesenchymal outlet septum. In the adult heart, however, this outlet septum is basically a muscular structure. Hence, the mesenchyme of the proximal outlet septum has to be replaced by cardiomyocytes. We have dubbed this process "myocardialization." Our immunohistochemical analysis of staged chicken hearts demonstrates that myocardialization takes place by ingrowth of existing myocardium into the mesenchymal outlet septum. Compared to other events in cardiac septation, it is a relatively late process, being initialized around stage H/H28 and being basically completed around stage H/H38. To unravel the molecular mechanisms that are responsible for the induction and regulation of myocardialization, an in vitro culture system in which myocardialization could be mimicked and manipulated was developed. Using this in vitro myocardialization assay it was observed that under the standard culture conditions (i) whole OFT explants from stage H/H20 and younger did not spontaneously myocardialize the collagen matrix, (ii) explants from stage H/H21 and older spontaneously formed extensive myocardial networks, (iii) the myocardium of the OFT could be induced to myocardialize and was therefore "myocardialization-competent" at all stages tested (H/H16-30), (iv) myocardialization was induced by factors produced by, most likely, the nonmyocardial component of the outflow tract, (v) at none of the embryonic stages analyzed was ventricular myocardium myocardialization-competent, and finally, (vi) ventricular myocardium did not produce factors capable of supporting myocardialization. PMID:10433836

van den Hoff, M J; Moorman, A F; Ruijter, J M; Lamers, W H; Bennington, R W; Markwald, R R; Wessels, A

1999-08-15

291

Histopathology of Early Myocardial Infarcts  

PubMed Central

The histopathology of human myocardial infarcts is reviewed in a series of 46 cases ranging from sudden death to a clinical age of 3 days. A set of histopathologic features is described whereby the diagnosis of acute myocardial infarction can be made, even in cases of sudden death, on routine sections and even after considerable autolysis. This is primarily a stretching and waviness of the myocardial fibers, especially at the border of the infarcted area. Its mechanism is probably twofold: the rythmical pull exerted by the normal myocardium against the infarcted paralyzed area and the outward bulging of this area at every systole. On the basis of human material alone, it may be inferred that this pattern develops very rapidly: surely less than 1 hour and perhaps a few minutes after the local circulation has failed. ImagesFig 15Fig 2Fig 16Fig 3Fig 17Fig 4Fig 5Fig 6Fig 7Fig 8Fig 9Figs 10 and 11Fig 12Fig 13Fig 14Fig 1 PMID:4359735

Bouchardy, Bernard; Majno, Guido

1974-01-01

292

ECG gating of thallium-201 myocardial images: effect on detection of ischemic heart disease  

SciTech Connect

Using the angiographic findings as the standard, we have examined the sensitivity and specificity of ECG-gated static thallium-201 myocardial images in 54 patients undergoing selective coronary arteriography. Gated and nongated images, each in anterior, 45 LAO, and 65 LAO projections, were processed by interpolative background subtraction. They were then analyzed separately by four independent observers who were unaware of patient identity, the results of coronary arteriography, and which studies were gated or nonongated. No significant differences were observed between the gated and ngated images regarding sensitivity or specificity, the detection rate for reversible myocardial ischmia, the accuracy of prediction of arteriographic extent of disease, or the degree of inter-or intraobserver variability. We conclude that ECG-gated acquisition of Tl-201 images does not produce any significant advantages, at least when interpolative background subtraction is used.

McKillop, J.H.; Fawcett, H.D.; Baumert, J.E.; McDougall, I.R.; DeBusk, R.F.; Harrison, D.C.; Goris, M.L.

1981-03-01

293

Tokamak reactor first wall  

NASA Astrophysics Data System (ADS)

A first wall construction for a tokamak reactor is disclosed. The wall comprises a series of hollow lobes, each with a pair of side wall portions with a curved end wall portion which extends between it. This invention relates to an improved first wall construction for a tokamak fusion reactor vessel, or other vessels subjected to similar pressure and thermal stresses.

Creedon, R. L.; Levine, H. E.; Wong, C.; Battaglia, J.

1984-11-01

294

Myocardial perfusion scintigraphy: the evidence  

PubMed Central

This review summarises the evidence for the role of myocardial perfusion scintigraphy (MPS) in patients with known or suspected coronary artery disease. It is the product of a consensus conference organised by the British Cardiac Society, the British Nuclear Cardiology Society and the British Nuclear Medicine Society and is endorsed by the Royal College of Physicians of London and the Royal College of Radiologists. It was used to inform the UK National Institute of Clinical Excellence in their appraisal of MPS in patients with chest pain and myocardial infarction. MPS is a well-established, non-invasive imaging technique with a large body of evidence to support its effectiveness in the diagnosis and management of angina and myocardial infarction. It is more accurate than the exercise ECG in detecting myocardial ischaemia and it is the single most powerful technique for predicting future coronary events. The high diagnostic accuracy of MPS allows reliable risk stratification and guides the selection of patients for further interventions, such as revascularisation. This in turn allows more appropriate utilisation of resources, with the potential for both improved clinical outcomes and greater cost-effectiveness. Evidence from modelling and observational studies supports the enhanced cost-effectiveness associated with MPS use. In patients presenting with stable or acute chest pain, strategies of investigation involving MPS are more cost-effective than those not using the technique. MPS also has particular advantages over alternative techniques in the management of a number of patient subgroups, including women, the elderly and those with diabetes, and its use will have a favourable impact on cost-effectiveness in these groups. MPS is already an integral part of many clinical guidelines for the investigation and management of angina and myocardial infarction. However, the technique is underutilised in the UK, as judged by the inappropriately long waiting times and by comparison with the numbers of revascularisations and coronary angiograms performed. Furthermore, MPS activity levels in this country fall far short of those in comparable European countries, with about half as many scans being undertaken per year. Currently, the number of MPS studies performed annually in the UK is 1,200/million population/year. We estimate the real need to be 4,000/million/year. The current average waiting time is 20 weeks and we recommend that clinically appropriate upper limits of waiting time are 6 weeks for routine studies and 1 week for urgent studies. PMID:15129710

Anagnostopoulos, C.; Cerqueira, M.; Ell, P. J.; Flint, E. J.; Harbinson, M.; Kelion, A. D.; Al-Mohammad, A.; Prvulovich, E. M.; Shaw, L. J.; Tweddel, A. C.

2003-01-01

295

Chronic effects of myocardial infarction on right ventricular function: a noninvasive assessment  

SciTech Connect

To assess the chronic effects of myocardial infarction on right ventricular function, 48 subjects were studied utilizing radionuclide angiography and two-dimensional echocardiography. Ten were normal subjects (group I), 11 had previous inferior wall myocardial infarction (group II), 10 had previous anteroseptal infarction (group III), 11 had combined anteroseptal and inferior infarction (group IV) and 6 had extensive anterolateral infarction (group V). The mean (+/- standard deviation) left ventricular ejection fraction was 0.66 +/- 0.03 in group I, 0.58 +/- 0.02 in group II, 0.52 +/- 0.02 in group III, 0.33 +/- 0.03 in group IV and 0.33 +/- 0.01 in group V. No systematic correlation between left and right ventricular ejection fraction was observed among the groups. The mean right ventricular ejection fraction was significantly reduced in the presence of inferior myocardial infarction (0.30 +/- 0.03 in group II and 0.29 +/- 0.03 in group IV compared with 0.43 +/- 0.02 in group I (p less than 0.001)). The group II and IV patients also had increased (p less than 0.001) right ventricular end-diastolic area and decreased (p less than 0.001) right ventricular free wall motion by two-dimensional echocardiography. In the presence of anteroseptal infarction (group III), right ventricular free wall motion was increased (p less than 0.05) compared with normal subjects (group I). Thus, the effects of prior myocardial infarction on right ventricular function depend more on the location of infarction than on the extent of left ventricular dysfunction. Inferior infarction was commonly associated with reduced right ventricular ejection fraction and increased right ventricular end-diastolic area. The right ventricular free wall excursion was increased in the presence of anteroseptal infarction, suggested loss of contribution of interventricular septal contraction to right ventricular ejection.

Kaul, S.; Hopkins, J.M.; Shah, P.M.

1983-10-01

296

Variants of cerebral arteries - anterior circulation  

PubMed Central

Summary Advances in imaging techniques allow for in vivo identification of abnormalities and normal variants of cerebral arteries. These arterial variations can be asymptomatic and uncomplicated although, some of them increase the risk of aneurysm formation, acute intracranial hemorrhage, play a vital role in neurosurgical planning or can be misidentified as serious pathology and medical errors. The goal of this publication is to discuss arterial anomalies of anterior cerebral circulation, their prevalence and demonstrate radiological images of some of those variants. In this article we will discuss variants of internal carotid artery, anterior cerebral artery, anterior communicating artery, middle cerebral artery, persistent stapedial artery and fenestration. PMID:24115959

Makowicz, Grzegorz; Poniatowska, Renata; Lusawa, Malgorzata

2013-01-01

297

Wall-E Learns About Proportion  

NSDL National Science Digital Library

Calculate the diameter of the moon with the help of Wall-E. In this video, the mischievous robot learns that the Lunar Reconnaissance Orbiter is mapping the moon. From Earth, the moon looks too small to land on. Wall-E learns to use math to determine the size of the moon. The moon is compared to the size of a baseball, and Earth is compared to the size of a basketball.

National Aeronautics and Space Administration (NASA)

2009-07-11

298

Susceptibility to myocardial ischemia reperfusion injury at early stage of type 1 diabetes in rats  

PubMed Central

Background Large body of evidences accumulated in clinical and epidemiological studies indicate that hearts of diabetic subjects are more sensitive to ischemia reperfusion injury (IRI), which results in a higher rate of mortality at post-operation than that of non-diabetes. However, experimental results are equivocal and point to either increased or decreased susceptibility of the diabetic hearts to IRI, especially at the early stage of the disease. The present study was designed to test the hypothesis that the duration/severity of the indexed ischemia is a major determinant of the vulnerability to myocardial IRI at early stage of diabetes. Methods Four weeks streptozotocin (STZ)-induced diabetic (D) and non-diabetic (C) Sprague–Dawley rats were randomly assigned to receive 30 or 45 min of left anterior descending artery ligation followed by 2 or 3 hours of reperfusion, respectively. Cardiac function was recorded by using Pressure-Volume (PV) conduction system. Myocardial infarct size was determined with triphenyltetrazolium chloride staining. Plasma Creatine kinase-MB (CK-MB), Lactate dehydrogenase (LDH) release, myocardial nitric oxide(NO) content and nitrotyrosine formation, 15-F2t-Isoprostane and plasma superoxide dismutase (SOD) were measured with colorimetric assays. Cardiomyocyte apoptosis was assessed by TUNEL staining. Myocardial TNF?, Caspase-3, STAT3, Akt, and GSK-3? were determined by Western blotting. Results Prolongation of ischemia but not reperfusion from 30 min to 45 min significantly increased infarct size in D compared to C rats (P?myocardial 15-F2t-Isoprostane and reduced plasma SOD activity, with concomitant reduction of myocardial NO and increase of nitrotyrosine formation in D relative to C (P?myocardial STAT3 at site Ser727 and Akt at site Ser473 as well as GSK-3? at Ser 9 (P?myocardial injury depends more on the duration of ischemia than that of reperfusion. PMID:24041262

2013-01-01

299

Ginsenoside Rb1 Preconditioning Enhances eNOS Expression and Attenuates Myocardial Ischemia/Reperfusion Injury in Diabetic Rats  

PubMed Central

Diabetes mellitus is associated with decreased NO bioavailability in the myocardium. Ginsenoside Rb1 has been shown to confer cardioprotection against ischemia reperfusion injury. The aim of this study was to investigate whether Ginsenoside Rb1 exerts cardioprotective effects during myocardial ischemia-reperfusion in diabetic rats and whether this effect is related to increase the production of NO via enhancing eNOS expression in the myocardium. The myocardial I/R injury were induced by occluding the left anterior descending artery for 30?min followed by 120?min reperfusion. An eNOS inhibitor L-NAME or Rb1 were respectively administered 25?min or 10?min before inducing ischemia. Ginsenoside Rb1 preconditioning reduced myocardial infarct size when compared with I/R group. Ginsenoside Rb1 induced myocardial protection was accompanied with increased eNOS expression and NO concentration and reduced plasma CK and LDH (P < 0.05). Moreover, the myocardial oxidative stress and tissue histological damage was attenuated by Ginsenoside Rb1 (P < 0.05). L-NAME abolished the protective effects of Ginsenoside Rb1. It is concluded that Ginsenoside Rb1 protects against myocardium ischemia/reperfusion injury in diabetic rat by enhancing the expression of eNOS and increasing the content of NO as well as inhibiting oxidative stress. PMID:22013385

Xia, Rui; Zhao, Bo; Wu, Yang; Hou, Jia-Bao; Zhang, Li; Xu, Jin-Jin; Xia, Zhong-Yuan

2011-01-01

300

Exercise-induced ventricular tachycardia in association with a myocardial bridge.  

PubMed

Sustained ventricular tachycardia induced by exercise is uncommon. This is a report of a patient who has a positive exercise test at a high level of exercise. The electrocardiogram has classic ischemic ST depressions. Following the appearance of these ST depressions, the patient developed ventricular tachycardia at a rapid rate. Workup that included an echocardiogram and cardiac catheterization revealed myocardial bridging of the left anterior descending artery as the only structural abnormality. Electrophysiologic studies revealed the patient to have ventricular tachycardia only with isoproterenol (Isuprel) infusion. PMID:2019202

Feld, H; Guadanino, V; Hollander, G; Greengart, A; Lichstein, E; Shani, J

1991-05-01

301

Myocardial contusion in patients with blunt chest trauma as evaluated by thallium 201 myocardial scintigraphy  

SciTech Connect

Fifty five patients suffering from blunt chest trauma were studied to assess the diagnosis of myocardial contusion using thallium 201 myocardial scintigraphy. Thirty-eight patients had consistent scintigraphic defects and were considered to have a myocardial contusion. All patients with scintigraphic defects had paroxysmal arrhythmias and/or ECG abnormalities. Of 38 patients, 32 had localized ST-T segment abnormalities; 29, ST-T segment abnormalities suggesting involvement of the same cardiac area as scintigraphic defects; 21, echocardiographic abnormalities. Sixteen patients had segmental hypokinesia involving the same cardiac area as the scintigraphic defects. Fifteen patients had clinical signs suggestive of myocardial contusion and scintigraphic defects. Almost 70 percent of patients with blunt chest trauma had scintigraphic defects related to areas of myocardial contusion. When thallium 201 myocardial scintigraphy directly showed myocardial lesion, two-dimensional echocardiography and standard ECG detected related functional consequences of cardiac trauma.

Bodin, L.; Rouby, J.J.; Viars, P.

1988-07-01

302

Ventral intradural endodermal cyst in the cervical spine treated with anterior corpectomy--case report.  

PubMed

A 14-year-old girl who presented with an endodermal cyst manifesting as severe neck and shoulder pain along with vesicorectal disturbances. Cervical magnetic resonance imaging showed a slightly enhanced intradural cyst at the C6-7 level in the ventral side of the spinal canal, with significant dorsal shortening and thinning of the spinal cord. Anterior corpectomy was chosen because of the dorsal effacement of the spinal cord. The cyst wall was subtotally removed to avoid damage to the normal spinal cord. After cyst removal, the iliac bone and an anterior cervical plate were used for anterior fusion. Postoperatively, her pain subsided without neurological deficits. The histological diagnosis was endodermal cyst. The cyst did not recur during a follow-up period of 18 months. Endodermal cysts are rare congenital lesions of the spine lined by endodermal epithelium. The natural history of this lesion is unclear, and the surgical strategy for the approach route and the extent of removal of the cyst wall remain controversial. We suggest that the anterior approach may allow a safer and more effective surgical route for the treatment of ventrally located endodermal cyst compared to the posterior approach. PMID:22198113

Ito, Kiyoshi; Aoyama, Tetsuro; Kiuchi, Takashi; Okada, Maki; Kanaya, Kohei; Muraoka, Hisashi; Horiuchi, Tetsuyoshi; Hongo, Kazuhiro

2011-01-01

303

Diagnosing the systemic associations of anterior uveitis.  

PubMed

Up to one-half of patients with anterior uveitis suffer from related systemic diseases. The common associations are the seronegative arthropathies and, in children, juvenile chronic arthritis. Anterior uveitis may also occur in the context of sarcoidosis or Behçet's disease. Syphilis and tuberculosis remain a significant problem for specific populations and may be the cause of anterior uveitis in these groups. By thorough clinical history and the correct selection and interpretation of simple investigations, it is generally possible for the ophthalmologist to make or exclude a systemic diagnosis, predict the ocular prognosis and direct selected patients to the appropriate physician. Diseases that threaten the patient's wellbeing must certainly be recognized. In the present review we present a method for identifying the systemic associations of anterior uveitis. PMID:9843260

Smith, J R; Coster, D J

1998-11-01

304

Anterior regeneration in the hemichordate Ptychodera flava  

PubMed Central

Ptychodera flava is a hemichordate whose anterior structures regenerate reproducibly from posterior trunk pieces when amputated. We characterized the cellular processes of anterior regeneration with respect to programmed cell death and cell proliferation, following wound healing. We found scattered proliferating cells at day two of regeneration using a PCNA antibody. On day four, most proliferating cells were associated with the nerve tract under the epidermis, and on day six, a small proboscis derived from proliferated cells was regenerated, and a mouth had broken though the epidermis. TUNEL detected elevated levels of apoptosis in the endoderm that began furthest away from the region of wound healing, then moved anteriorly over eight days. Posterior to anterior apoptosis is likely to remove digestive endoderm for later differentiation of pharyngeal endoderm. We hypothesize that P. flava regeneration is nerve dependent and that remodeling in the gut endoderm plays an important role in regeneration. PMID:18924231

Rychel, Amanda L.; Swalla, Billie J.

2008-01-01

305

Vascular injury during anterior lumbar surgery  

Microsoft Academic Search

Background contextWith the number of anterior lumbar procedures expected to increase significantly over the next few years, it is important for spine surgeons to have a good understanding about the incidence of vascular complications during these operations.

Salvador A Brau; Rick B Delamarter; Michael L Schiffman; Lytton A Williams; Robert G Watkins

2004-01-01

306

38 CFR 3.379 - Anterior poliomyelitis.  

Code of Federal Regulations, 2010 CFR

If the first manifestations of acute anterior poliomyelitis present themselves in a veteran within 35 days of termination of active military service, it is probable that the infection occurred during...

2010-07-01

307

Ultrasound of the male anterior urethra.  

PubMed

Ascending and descending techniques are used to demonstrate the male anterior urethra. The authors developed an ultrasound approach with the patient compressing his own urethra manually during voiding to achieve distension of the urethra with urine. The subsequent sonourethrography is more accurate than conventional fluoroscopic contrast studies in defining urethral filling defects and is as accurate for the demonstration of strictures. The technique has replaced contrast urethrography at the authors' institutions for the routine evaluation of the anterior urethra. PMID:12970608

Berman, Laurence H; Bearcroft, Philip W P; Spector, Sol

2002-06-01

308

Dentulous Appliance for Upper Anterior Edentulous Span  

PubMed Central

This article discusses about a fixed dentulous appliance that was constructed to replace the primary upper anterior edentulous span in a four year old girl. It constituted a design, whereby the maxillary primary second molars were used to support the appliance through bands and a wire that contained an acrylic flange bearing trimmed acrylic teeth, anteriorly. The appliance was functionally and aesthetically compliant. PMID:24551736

Chalakkal, Paul; Devi, Ramisetty Sabitha; Srinivas, G. Vijay; Venkataramana, Pammi

2013-01-01

309

Quantification of myocardial infarction: a comparison of single photon-emission computed tomography with pyrophosphate to serial plasma MB-creatine kinase measurements  

SciTech Connect

Single photon-emission computed tomography (SPECT) with /sup 99m/Tc-pyrophosphate (PPi) has been shown to estimate size of myocardial infarction accurately in animals. The authors tested the hypothesis that SPECT with /sup /sup 99m//Tc-PPi and blood pool subtraction can provide prompt and accurate estimates of size of myocardial infarction in patients. SPECT estimates are potentially available early after the onset of infarction and should correlate with estimates of infarct size calculated from serial measurements of plasma MB-creatine kinase (CK) activity. Thirty-three patients with acute myocardial infarction and 16 control patients without acute myocardial infarction were studied. Eleven of the patients had transmural anterior myocardial infarction, 16 had transmural inferior myocardial infarction, and six had nontransmural myocardial infarction. SPECT was performed with a commercially available rotating gamma camera. Identical projection images of the distribution of 99mTc-PPi and the ungated cardiac blood pool were acquired sequentially over 180 degrees. Reconstructed sections were color coded and superimposed for purposes of localization of infarct. Areas of increased PPi uptake within myocardial infarcts were thresholded at 65% of peak activity. The blood pool was thresholded at 50% and subtracted to determine the endocardial border for the left ventricle. Myocardial infarcts ranged in size from 1 to 126 gram equivalents (geq) MB-CK. The correlation of MB-CK estimates of size of infarct with size determined by SPECT (both in geq) was good (r = .89 with a regression line of y = 13.1 + 1.5x).

Jansen, D.E.; Corbett, J.R.; Wolfe, C.L.; Lewis, S.E.; Gabliani, G.; Filipchuk, N.; Redish, G.; Parkey, R.W.; Buja, L.M.; Jaffe, A.S.

1985-08-01

310

Acute insulin resistance in ST-segment elevation myocardial infarction in non-diabetic patients is associated with incomplete myocardial reperfusion and impaired coronary microcirculatory function  

PubMed Central

Background Insulin resistance (IR) assessed by the Homeostatic Model Assessment (HOMA) index in the acute phase of myocardial infarction in non-diabetic patients was recently established as an independent predictor of intrahospital mortality. In this study we postulated that acute IR is a dynamic phenomenon associated with the development of myocardial and microvascular injury and larger final infarct size in patients with ST-segment elevation myocardial infarction (STEMI) treated by primary percutaneous coronary intervention (pPCI). Methods In 104 consecutive patients with the first anterior STEMI without diabetes, the HOMA index was determined on the 2nd and 7th day after pPCI. Worst-lead residual ST-segment elevation (ST-E) on postprocedural ECG, coronary flow reserve (CFR) determined by transthoracic Doppler echocardiography on the 2nd day after pPCI and fixed perfusion defect on single-photon emission computed tomography myocardial perfusion imaging (SPECT-MPI) determined six weeks after pPCI were analyzed according to HOMA indices. Results IR was present in 55 % and 58 % of patients on day 2 and day 7, respectively. Incomplete post-procedural ST-E resolution was more frequent in patients with IR compared to patients without IR, both on day 2 (p?=?0.001) and day 7 (p? 20% (OR 11.37, 95% CI 1.34-96.21, p?=?0.026). Conclusion IR assessed by the HOMA index during the acute phase of the first anterior STEMI in patients without diabetes treated by pPCI is independently associated with poorer myocardial reperfusion, impaired coronary microcirculatory function and potentially with larger final infarct size. PMID:24708817

2014-01-01

311

Coronary spasm in acute myocardial infarction  

Microsoft Academic Search

A 30 year old man had an acute anterolateral myocardial infarction following which he developed unstable angina requiring percutaneous transluminal coronary angioplasty. He subsequently developed further angina with recurrence of coronary artery lesions that were reversed by intracoronary nitrate. A diagnosis of prinzmetal (vasospastic) angina was made and this had been the apparent cause of his myocardial infarction. He was

G Y H Lip; K K Ray; M F Shiu

1998-01-01

312

An Aspergillus myocardial abscess diagnosed by echocardiography.  

PubMed

This is a rare case of Aspergillus myocardial abscess in 19-year-old woman with acute lymphoblastic leukemia treated by chemotherapy. During pancytopenia she developed invasive aspergillosis with myocardial abscess. The presence of specific antigen in the pericardial effusion was diagnostic. She died despite vigorous antifungal therapy. PMID:18222638

Kemdem, Arsène; Ahmad, Imran; Ysebrand, Laure; Nouar, Elias; Silance, Paul-Gael; Aoun, Mickael; Bron, Dominique; Vandenbossche, Jean-Luc

2008-10-01

313

Modulation of myocardial contraction by peroxynitrite  

PubMed Central

Peroxynitrite is a potent oxidant that is quickly emerging as a crucial modulator of myocardial function. This review will focus on the regulation of myocardial contraction by peroxynitrite during health and disease, with a specific emphasis on cardiomyocyte Ca2+ handling, proposed signaling pathways, and protein end-targets. PMID:23248603

Kohr, Mark J.; Roof, Steve R.; Zweier, Jay L.; Ziolo, Mark T.

2012-01-01

314

Visualizing myocardial function using HARP MRI  

Microsoft Academic Search

Harmonic phase magnetic resonance imaging (HARP) is a new technique for measuring the motion of the left ventricle of the heart. HARP uses magnetic resonance tagging, Fourier filtering and special processing algorithms to calculate key indices of myocardial motion including Eulerian and Lagrangian strain. This paper presents several new methods for visualizing myocardial motion based on HARP. Quantities that are

Nael F Osman; Jerry L Prince

2000-01-01

315

Autologous Stem Cells for Functional Myocardial Repair  

Microsoft Academic Search

Recent experimental studies based on innovative hypothesis utilizing cell therapy for the damaged myocardium are recently becoming increasingly promising. The naturally occurring myocardial reparative process is apparently complex and relatively inefficient. It consists of up-regulation of progenitor cell release from the bone marrow after myocardial infarction, homing of these cells to the injured tissue, and differentiation of these progenitor cells

Yitzhack Schwartz; Ran Kornowski

2003-01-01

316

Myocardial injury following multiple bee stings.  

PubMed

Envenomation by the honey bee can cause multi-organ dysfunction as a result of toxic effects and may cause a severe anaphylactic reaction. Acute myocardial ischemia is an extremely rare complication of bee envenomation. We report a case of a 58-year-old woman with acute myocardial injury following massive bee envenomation. PMID:24569098

Nisahan, Balasingam; Selvaratnam, Gowri; Kumanan, Thirunavukarasu

2014-10-01

317

Coronary autoregulation and optimal myocardial oxygen utilization  

Microsoft Academic Search

The complex relationship among myocardial contractility, preload, afterload, and coronary autoregulation was studied using both analytical and numerical methods. To study autoregulation and coronary reserve changes in response to changes in cardiac oxygen consumption and in arterial pressure generation, a new variable was introduced: myocardial resistance to oxygen flow (\\u000a

O. Barnea; W. P. Santamore

1992-01-01

318

Myocardial infarction in an adult with cystic fibrosis and heart and lung transplant  

PubMed Central

We present a case of myocardial infarction in a 19 year old female with cystic fibrosis who had a heart and lung transplant performed at the age of four years old. She presented atypically with a one day history of severe, intermittent, central, sharp chest pain, radiating to her back and down her left arm. A coronary angiogram showed proximal stenosis of the left anterior descending artery and right coronary artery. She was treated with percutaneous coronary intervention, involving drug eluting stents to the left anterior descending artery (LAD) and the right coronary artery (RCA). In this study we discuss the pathophysiology, investigations and treatment of cardiac transplant vasculopathy. Although complete reversal of LAD and RCA stenosis was achieved, routine follow-up with coronary angiography and careful control of cardiac risk factors will be important to identify and reduce future restenosis and adverse cardiac events. PMID:23759073

2013-01-01

319

Prostanoids suppress the coronary vasoconstrictor influence of endothelin after myocardial infarction.  

PubMed

Myocardial infarction (MI) is associated with endothelial dysfunction resulting in an imbalance in endothelium-derived vasodilators and vasoconstrictors. We have previously shown that despite increased endothelin (ET) plasma levels, the coronary vasoconstrictor effect of endogenous ET is abolished after MI. In normal swine, nitric oxide (NO) and prostanoids modulate the vasoconstrictor effect of ET. In light of the interaction among NO, prostanoids, and ET combined with endothelial dysfunction present after MI, we investigated this interaction in control of coronary vasomotor tone in the remote noninfarcted myocardium after MI. Studies were performed in chronically instrumented swine (18 normal swine; 13 swine with MI) at rest and during treadmill exercise. Furthermore, endothelial nitric oxide synthase (eNOS) and cyclooxygenase protein levels were measured in the anterior (noninfarcted) wall of six normal and six swine with MI. eNOS inhibition with N(?)-nitro-L-arginine (L-NNA) and cyclooxygenase inhibition with indomethacin each resulted in coronary vasoconstriction at rest and during exercise, as evidenced by a decrease in coronary venous oxygen levels. The effect of l-NNA was slightly decreased in swine with MI, although eNOS expression was not altered. Conversely, in accordance with the unaltered expression of cyclooxygenase-1 after MI, the effect of indomethacin was similar in normal and MI swine. L-NNA enhanced the vasodilator effect of the ET(A/B) receptor blocker tezosentan but exclusively during exercise in both normal and MI swine. Interestingly, this effect of L-NNA was blunted in MI compared with normal swine. In contrast, whereas indomethacin increased the vasodilator effect of tezosentan only during exercise in normal swine, indomethacin unmasked a coronary vasodilator effect of tezosentan in MI swine both at rest and during exercise. In conclusion, the present study shows that endothelial control of the coronary vasculature is altered in post-MI remodeled myocardium. Thus the overall vasodilator influences of NO as well as its inhibition of the vasoconstrictor influence of ET on the coronary resistance vessels were reduced after MI. In contrast, while the overall prostanoid vasodilator influence was maintained, its inhibition of ET vasoconstrictor influences was enhanced in post-MI remote myocardium. PMID:21685265

de Beer, Vincent J; Taverne, Yannick J; Kuster, Diederik W; Najafi, Aref; Duncker, Dirk J; Merkus, Daphne

2011-09-01

320

Myocardial oxygen consumption in aortic valve disease with and without left ventricular dysfunction.  

PubMed Central

OBJECTIVE--To assess whether and to what extent myocardial oxygen consumption is modified by hypertrophy and alterations in contractility in patients with aortic valve disease and to evaluate the influence of regression of left ventricular hypertrophy and improvement of contractility on myocardial oxygen consumption after successful aortic valve replacement. DESIGN--A cohort analytical study to investigate the influence of the "explanatory" variables of myocardial oxygen consumption by multiple regression analysis. A comparison of myocardial oxygen consumption in preoperative patients with that after operation in a group with comparable severity of aortic valve disease before operation (analysis of covariance). PATIENTS--In six controls and in 43 patients with aortic valve disease and normal coronary arteries standard haemodynamic variables were measured, left ventricular biplane cineangiography performed, and coronary sinus blood flow measured by thermodilution. The patients were divided into three groups: 19 preoperative patients with normal ejection fraction (greater than or equal to 57%) (group 1); nine preoperative patients with reduced ejection fraction (less than 57%) (group 2); 16 postoperative patients (one with preoperative and postoperative measurements (group 3). Postoperative evaluation was performed 12-51 months after surgery. MAIN OUTCOME MEASUREMENTS--Myocardial oxygen consumption/100 g left ventricular muscle mass and its suspected "explanatory" variables--that is, peak systolic left ventricular circumferential wall stress, heart rate, contractility (assessed by left ventricular ejection fraction), and left ventricular muscle mass index. RESULTS--Multiple regression analysis showed that the product of peak systolic stress and heart rate (p less than 0.0001) and ejection fraction (p less than 0.03) were positively correlated with myocardial oxygen consumption/100 g and that left ventricular muscle mass index (p less than 0.002) was negatively correlated with myocardial oxygen consumption/100 g (r = 0.72; n = 50 measurements). Myocardial oxygen consumption per 100 g at a given stress-rate product was higher in the controls than in group 1 (hypertrophied ventricles with normal ejection fraction) and was also higher in group 1 than in group 2 (hypertrophied ventricles with reduced ejection fraction). In a subgroup of the postoperative patients with complete regression of hypertrophy and normalisation of contractility, myocardial oxygen consumption per 100 g at a given stress-rate product was indistinguishable from that in controls. CONCLUSIONS--When the actual stress-rate product was used as an index of overall left ventricular performance the results suggested that mechanical efficiency was increased in hypertrophied ventricles especially when contractility was decreased. These changes in mechanical efficiency seemed to be reversible during the postoperative course when muscle mass and contractility returned to normal. PMID:1531759

Schwitter, J; Eberli, F R; Ritter, M; Turina, M; Krayenbuehl, H P

1992-01-01

321

Value of myocardial SPECT in early detection of ischaemia in children with sickle cell anaemia  

PubMed Central

Background Cardiovascular complications of sickle cell anaemia (SCA) are relatively infrequent compared with other cerebral and skeletal insults. However, myocardial infarction and cardiac dysfunction have been reported in autopsied patients with SCA. When left ventricular functional parameters of gated SPECT and echocardiography were compared incidentally in children with SCA, some 26% of patients were found to have evident myocardial ischaemia. This stimulated the current work with the aim to further analyse these incidental findings and evaluate the possible role of SPECT in early detection of coronary insufficiency in children with SCA. Patients and methods Twenty-seven patients (19 girls, 8 boys), mean age 9.2±4.2 years, with SCA were examined by baseline ECG, echocardiography and gated SPECT. They were all free from any cardiac symptoms. Intravenous injection of 5 to 10 mCi 99MTc-MIBI or 99MTc-Myoview was administered, according to the predetermined weight-dependent paediatric dose. Stress SPECT was obtained 45 to 60 minutes after tracer injection, which took place at peak physical exercise (6 patients) or 3 to 4 minutes after IV infusion of dipyridamole pharmacological stress (21 patients). Rest SPECT study was acquired 4 to 5 hours later after a second injection of 99MTc-MIBI/Myoview. A semiquantitative nine-segment stress/rest bull's eye model was used to assess to the presence/extent of myocardial ischaemia. Results Myocardial perfusion was normal in 20 patients (74%). Seven patients (26%) had significant perfusion defects in the stress images. Four of them showed perfusion defect in one or two segments. Complete reversibility in the rest study was seen in all patients. Two patients showed a mixture of reversible and fixed perfusion defects in four segments. One patient had evident left ventricular dilatation with multiple fixed and reversible defects (cardiomyopathy). In this case, a diffusely reduced myocardial wall contractility was seen and a low LVEF of 42% as assessed by echocardiography. This was the only case showing agreement between the echo and SPECT findings. In the whole cohort the EF% and FS% by echocardiography were 61.7±5.9% and 33.2±3.4% respectively (mean±SD). There were no significant relations between myocardial perfusion abnormalities when compared with EF% and FS%; (p>0.05). Conclusion Cardiac involvement in the form of myocardial ischaemia should be regarded as a high-risk complication in patients with SCA. Myocardial perfusion scintigraphy succeeded in the early detection of myocardial perfusion abnormalities in patients with SCA. ImagesFigure 2Figure 3Figure 4

El-Maghraby, T.A.F.; Mosaad, N; El Refaie, S.; Samir, M.

2002-01-01

322

Risk stratification after myocardial infarction. Clinical overview  

SciTech Connect

Many patients with an acute myocardial infarction can be stratified into subgroups that are at high risk for morbidity and mortality on the basis of clinical characteristics that indicate recurrent myocardial ischemia, persistent left ventricular dysfunction, and/or recurrent cardiac arrhythmias. In patients with uncomplicated myocardial infarction the assessment of symptoms, physical findings, and ECG changes during predischarge exercise testing often identifies patients at increased risk for further cardiac events. Because of the suboptimum sensitivity and specificity of the exercise ECG for detecting myocardial ischemia, myocardial perfusion imaging with 201Tl and/or assessment of global and segmental ventricular function by two-dimensional echocardiography or radionuclide cineangiography during or immediately after exercise are often added to the predischarge risk stratification.

O'Rourke, R.A. (Department of Medicine, University of Texas Health Science Center, San Antonio (United States))

1991-09-01

323

[Myocardial infarction in infective endocarditis].  

PubMed

Two patients with chronic valvular heart disease and myocardial infarction were assisted at our hospital. Both of them were febrile and only one had petechiae associated with signs of valvular involvement led to suspicion of infective endocarditis. Although blood cultures were negative, echocardiographic, surgical and anatomopathologic findings were compatible with infective endocarditis. They required cardiac surgery during the acute phase of the infection because they presented progressive hemodynamic deterioration and no satisfactory response to antimicrobial regimen too. One patient died at late follow-up (two weeks after the hospital discharge) and the other survived, but with signs of cardiac failure (class II of NYHA) one year after the procedure. PMID:7944984

Jorge, S do C; Arêas, C A; Shibata, M; Assef, J E; Arnoni, A S; Zamorano, M M; da Silva, L M; Souza, L C; Piegas, L S; Magalhães, H M

1994-02-01

324

Cardioprotective activity of silymarin in ischemia-reperfusion-induced myocardial infarction in albino rats  

PubMed Central

BACKGROUND There is comprehensive experimental and clinical evidence that either exogenous supplementation of natural antioxidants or augmentation of endogenous antioxidants attenuates myocardial infarction. OBJECTIVES To investigate the effects of chronic administration of silymarin against ischemia-reperfusion-induced myocardial infarction in rats. METHODS Silymarin was administered orally to Wistar albino rats (200 g to 250 g) in three different doses (100 mg/kg, 250 mg/kg and 500 mg/kg), by gastric gavage for one week. At the end of this period, control (ischemia-reperfusion) groups and silymarin-treated groups were subjected to 30 min occlusion of the left anterior descending coronary artery and thereafter reperfused for 4 h. RESULTS Ischemia-reperfusion resulted in significant cardiac necrosis, indicated by elevated levels of serum marker enzymes such as serum glutamate oxaloacetate transaminase, serum glutamate pyruvate transaminase, lactate dehydrogenase, creatine kinase-isoenzyme and creatine kinase. A significant rise in the end products of myocardial lipid peroxides (malondialdehydes [MDAs]), loss of antioxidative enzymes (superoxide dismutase, catalase, glutathione S-transferase and reduced glutathione) and increased levels of myeloperoxidase in heart tissue were observed in the animals subjected to in vivo myocardial ischemia-reperfusion injury. Infarct size was measured by using the staining agent 2,3,5-triphenyltetrazolium chloride. A lead II electrocardiogram was monitored at various intervals throughout the experiment. DISCUSSION The present study showed that silymarin protected the endogenous antioxidant enzymes, suppressed the neutrophil infiltration during ischemia-reperfusion and limited the infarct size, with concomitant reduction in serum MDA, tissue MDA and serum marker enzymes in rats subjected to 30 min coronary artery occlusion followed by 4 h of reperfusion. Pretreatment with silymarin also protected rat hearts from a further drop in mean arterial blood pressure during reperfusion, and restored heart rate at the end of the reperfusion period. CONCLUSIONS The present study suggests that the phytochemical silymarin has cardioprotective activity against ischemia-reperfusion-induced myocardial infarction in rats. PMID:18651002

Rao, Pragada Rajeswara; Viswanath, Routhu Kasi

2007-01-01

325

Ventricular function and infarct size: the Western Washington Intravenous Streptokinase in Myocardial Infarction Trial  

SciTech Connect

The Western Washington Intravenous Streptokinase in Acute Myocardial Infarction Trial randomized 368 patients with symptoms and signs of acute myocardial infarction of less than 6 h duration to either conventional care or 1.5 million units of intravenous streptokinase. The mean time to randomization was 209 min and 52% of patients were randomized within 3 h of symptom onset. Quantitative, tomographic thallium-201 infarct size and radionuclide ejection fraction were measured at 8.2 +/- 7.5 weeks in 207 survivors who lived within a 100 mile radius of a centralized laboratory. Overall, infarct size as a percent of the left ventricle was 19 +/- 13% for control subjects and 15 +/- 13% for treatment patients (p = 0.03). For anterior infarction in patients entered within 3 h of symptom onset, infarct size was 28 +/- 13% in the control group versus 19 +/- 15% for the treatment group (p = 0.09). Left ventricular ejection fraction was 47 +/- 15% in the control versus 51 +/- 15% in the treatment group (p = 0.08). For anterior infarction of less than 3 h duration, the ejection fraction was 38 +/- 16% in the control versus 48 +/- 20% in the treatment group (p = 0.13). By statistical analysis incorporating the nonsurvivors, p values for all of these variables were less than or equal to 0.08. There was no benefit for patients with inferior infarction or for anterior infarction of greater than 3 h duration. It is concluded that intravenous streptokinase, when given within 3 h of symptom onset to patients with anterior infarction, reduces infarct size and improves ventricular function.

Ritchie, J.L.; Cerqueira, M.; Maynard, C.; Davis, K.; Kennedy, J.W.

1988-04-01

326

Coronary steal due to ruptured right coronary aneurysm causing myocardial infarction in a patient with systemic lupus erythematosus  

PubMed Central

A 34-year-old female with a history of systemic lupus erythematosus (SLE) developed an acute inferior myocardial infarction while hospitalized for methicillin-resistant Staphylococcus Aureus sepsis. An emergent coronary angiography revealed an ectatic proximal left coronary artery and a huge aneurysm (37 mm × 32 mm) in the mid-portion of the right coronary artery, which had ruptured into the right atrium. A “steal phenomenon” due to significant left to right shunt resulting from the ruptured aneurysm was the cause of the myocardial infarction. Infection of the wall of the aneurysm might have contributed to the growth and the rupture in the presence of a pre-existing coronary aneurysm.

Yagi, Nobuhito; Wake, Minoru; Takahashi, Takanori; Nakazato, Jun; Miyagi, Tadayoshi; Shimotakahara, Junichi

2014-01-01

327

Wall surveyor project report  

Microsoft Academic Search

A report is made on the demonstration of a first-generation Wall Surveyor that is capable of surveying the interior and thickness of a stone, brick, or cement wall. LLNL`s Micropower Impulse Radar is used, based on emitting and detecting very low amplitude and short microwave impulses (MIR rangefinder). Six test walls were used. While the demonstrator MIR Wall Surveyor is

D. J. Mullenhoff; B. C. Johnston; S. G. Azevedo

1996-01-01

328

Mechanisms Involved in the Beneficial Effects of Spironolactone after Myocardial Infarction  

PubMed Central

Introduction Our objective was to analyze the effect of spironolactone on cardiac remodeling after experimental myocardial infarction (MI), assessed by matricellular proteins levels, cardiac collagen amount and distribution, myocardial tissue metalloproteinase inhibitor-1(TIMP-1) concentration, myocyte hypertrophy, left ventricular architecture, and in vitro and in vivo cardiac function. Methods Wistar rats were assigned to 4 groups: control group, in which animals were submitted to simulated surgery (SHAM group; n=9); group that received spironolactone and in which animals were submitted to simulated surgery (SHAM-S group, n=9); myocardial infarction group, in which animals were submitted to coronary artery ligation (MI group, n=15); and myocardial infarction group with spironolactone supplementation (MI-S group, n=15). The rats were observed for 3 months. Results The MI group had higher values of left cardiac chambers and mass index and lower relative wall thicknesses compared with the SHAM group. In addition, diastolic and systolic functions were worse in the MI groups. However, spironolactone did not influence any of these variables. The MI-S group had a lower myocardial hydroxyproline concentration and myocyte cross-sectional area compared with the MI group. Myocardial periostin and collagen type III were lower in the MI-S group compared with the MI-group. In addition, TIMP-1 concentration in myocardium was higher in the MI-S group compared with the MI group. Conclusions The predominant consequence of spironolactone supplementation after MI is related to reductions in collagens, with discrete attenuation of other remodeling variables. Importantly, this effect may be modulated by periostin and TIMP-1 levels. PMID:24098808

Minicucci, Marcos F.; dos Santos, Priscila P.; Rafacho, Bruna P. M.; Goncalves, Andrea F.; Silva, Renata A. C.; Chiuso-Minicucci, Fernanda; Azevedo, Paula S.; Polegato, Bertha F.; Okoshi, Katashi; Pereira, Elenize J.; Paiva, Sergio A. R.; Zornoff, Leonardo A. M.

2013-01-01

329

Wall surveyor project report  

SciTech Connect

A report is made on the demonstration of a first-generation Wall Surveyor that is capable of surveying the interior and thickness of a stone, brick, or cement wall. LLNL`s Micropower Impulse Radar is used, based on emitting and detecting very low amplitude and short microwave impulses (MIR rangefinder). Six test walls were used. While the demonstrator MIR Wall Surveyor is not fieldable yet, it has successfully scanned the test walls and produced real-time images identifying the walls. It is planned to optimize and package the evaluation wall surveyor into a hand held unit.

Mullenhoff, D.J.; Johnston, B.C.; Azevedo, S.G.

1996-02-22

330

Giant anterior cervical osteophyte leading to Dysphagia.  

PubMed

Large anterior cervical osteophytes can occur in degeneration of the cervical spine or in diffuse idiopathic skeletal hyperostosis(DISH). Large osteophytes can produce otolaryngological symptoms such as dysphagia, dysphonia, and foreign body sensation. We describe a DISH patient with giant anterior cervical osteophyte causing chronic dysphagia and dysphonia. A 56-year-old man presented with increasing dysphagia, dysphonia, neck pain and neck stiffness. Physical examination of the neck showed a non-tender and hard mass on the left side at the level of C4-5. Radiography showed extensive ossification of anterior longitudinal ligament along the left anterolateral aspect of vertebral bodies from C2 to T1. The ossification was espe cially prominent at the level of C4-5 and linear breakage was noted at same level. Esophagogram revealed a filling defect along the pharynx and lateral displacement of the esophagus. Giant anterior cervical osteophyte was removed through the leftsided anterolateral cervical approach to the spine. Anterior cervical interbody fusion at C4-5 was followed by posterior cervical fixation using lateral mass screws from C3 to C6. After surgery, dysphagia and dysphonia improved immediately. One year later, cervical CT showed bone fusion at C4-5 bodies and no recurrence of osteophyte. DISH is a common cause of anterior cervical osteophyte leading to progressive dysphagia. Keeping this clinical entity in the differential diagnosis is important in patients with progressive neck stiffness, dysphagia or dysphonia. And surgical treatment of symptomatic anterior cervical osteophyte due to DISH should be considered with a solid fusion procedure preventing postoperative instability or osteophyte progress. PMID:24757489

Hwang, Jin Seop; Chough, Chung Kee; Joo, Won Il

2013-09-01

331

Circadian influences on myocardial infarction  

PubMed Central

Components of circadian rhythm maintenance, or “clock genes,” are endogenous entrainable oscillations of about 24 h that regulate biological processes and are found in the suprachaismatic nucleus (SCN) and many peripheral tissues, including the heart. They are influenced by external cues, or Zeitgebers, such as light and heat, and can influence such diverse phenomena as cytokine expression immune cells, metabolic activity of cardiac myocytes, and vasodilator regulation by vascular endothelial cells. While it is known that the central master clock in the SCN synchronizes peripheral physiologic rhythms, the mechanisms by which the information is transmitted are complex and may include hormonal, metabolic, and neuronal inputs. Whether circadian patterns are causally related to the observed periodicity of events, or whether they are simply epi-phenomena is not well established, but a few studies suggest that the circadian effects likely are real in their impact on myocardial infarct incidence. Cycle disturbances may be harbingers of predisposition and subsequent response to acute and chronic cardiac injury, and identifying the complex interactions of circadian rhythms and myocardial infarction may provide insights into possible preventative and therapeutic strategies for susceptible populations.

Virag, Jitka A. I.; Lust, Robert M.

2014-01-01

332

Apical myocardial infarction with bizarre coronary images mimicking left ventricular apical ballooning syndrome: a case report  

PubMed Central

Introduction Although several etiopathogenetic mechanisms have been proposed, the causes of left ventricular apical ballooning syndrome are still controversial. Case presentation A 51-year-old Japanese woman consulted the emergency room complaining of the sudden onset of anterior chest pain while shopping. We initially suspected her disease as left ventricular apical ballooning syndrome based on her clinical background and laboratory examinations. However, the initial coronary angiogram demonstrated diffuse lesions in her distal left anterior descending coronary artery, and she was finally diagnosed with apical myocardial infarction. The blood flow in her distal left anterior descending coronary artery had markedly improved in the chronic phase. If the reduced blood flow in her distal left anterior descending coronary artery was induced by coronary vasospasm and the vasospasm was relieved before the coronary angiogram was performed, this case must be diagnosed as left ventricular apical ballooning syndrome. Conclusion We think this case may promote discussion regarding the pathophysiology of left ventricular apical ballooning syndrome. PMID:24716472

2014-01-01

333

If walls could talk  

NASA Technical Reports Server (NTRS)

The plant cell wall is very complex, both in structure and function. The wall components and the mechanical properties of the wall have been implicated in conveying information that is important for morphogenesis. Proteoglycans, fragments of polysaccharides and the structural integrity of the wall may relay signals that influence cellular differentiation and growth control. Furthering our knowledge of cell wall structure and function is likely to have a profound impact on our understanding of how plant cells communicate with the extracellular environment.

Braam, J.; McIntire, L. V. (Principal Investigator)

1999-01-01

334

Interactive Care Wall  

Microsoft Academic Search

We propose a video-mediated interactive care wall as a way of sup- porting a face-to-face like care between elders and their remote caregivers. This interactive care wall attempts to interconnect two physically-disjoint spaces by linking one wall on the elder's living space and one wall on the caregivers' liv- ing space. To make this interconnection appears seamless, the care wall

Chu-feng Lien; Hao-ji Wu; Hao-hua Chu

335

Reversal of rest myocardial asynergy during exercise: a radionuclide scintigraphic study  

SciTech Connect

While exercise-induced segmental left ventricular wall motion abnormalities are well described, the phenomenon of improvement in certain asynergic segments during exercise in some patients remains a curiosity. To assess this unexpected finding, results were analyzed in 85 patients with wall motion abnormalities at rest who underwent two view exercise radionuclide ventriculography and exercise thallium-201 myocardial perfusion imaging. Wall motion was scored with a 5 point system; normalization or increase of 2 or more points with exercise signified improvement. Forty-eight patients (56%) had no change or further deterioration of wall motion at peak exercise, 15 (18%) showed both improvement of wall motion and deterioration and 22 (26%) showed only improvement of wall motion. Wall motion improvement during exercise was found in 57 (20%) of 279 segments with asynergy at rest. Of these 57 segments improving with exercise, 45 (79%) showed mild and 12 (21%) showed severe asynergy at rest. Only seven segments (12%) were associated with pathologic Q waves. Thallium-201 perfusion was normal in 44 segments (77%) while only 6 segments (11%) had reversible and only 7 (12%) had nonreversible thallium-201 defects. In conclusion segments with abnormal wall motion at rest that show improvement with exercise appear to represent viable nonischemic segments.

Kimchi, A.; Rozanski, A.; Fletcher, C.; Maddahi, J.; Swan, H.J.; Berman, D.S.

1985-11-01

336

Anterior clinoid mucocele coexisting with sphenoid sinus mucocele  

Microsoft Academic Search

An anterior clinoid mucocele, known to be extremely rare, can lead to visual complications due to its proximity to the optic nerve. We report a patient who developed visual disturbance due to an anterior clinoid mucocele. Interestingly, the anterior clinoid mucocele coexisted with a sphenoid sinus mucocele. When an anterior clinoid mucocele coexists with a sphenoid sinus mucocele, more deliberate

Soon Ho Kwon; Si Hong Kim; Joo-Heon Yoon

2009-01-01

337

Noninvasive measurement and clinical relevance of myocardial twist and torsion.  

PubMed

Left ventricular (LV) torsion (twisting) and untwisting results in equalization of wall stress and augmentation of pressure generated for a given shortening of sarcomere during the systolic contraction and aids early diastolic relaxation. This is attributed to the dynamic interaction of epicardial and endocardial helical myocardial fibers. Recent advances in noninvasive imaging techniques have enabled us to quantify torsion accurately and reliably in health and disease. LV torsional mechanics are altered in range of clinical conditions from those that cause minimal cardiac architectural changes as seen in hypertension, diabetes mellitus or older age to advanced cardiac remodeling as seen dilated or hypertrophic cardiomyopathy. Therefore, assessment of LV rotational mechanics may be a potentially sensitive marker of cardiac dysfunction and may provide important insights into the pathophysiology of heart failure. PMID:25318986

Pokharel, Parash; Yoon, Andrew J; Bella, Jonathan N

2014-11-01

338

Myocardial preconditioning: a model or a phenomenon?  

PubMed

A brief ischemic episode (ischemic preconditioning) limits myocardial necrosis produced by a prolonged period of coronary artery occlusion and reperfusion. In absence of infarction, lack of cumulative ATP depletion, and ventricular arrhythmias and dysfunction "stunning" in models of intermittent ischemia and reperfusion also could be a component of an adaptive response to brief ischemia (preconditioning). Nonischemic stimuli also precondition the myocardium against ventricular arrhythmias and infarction by activating endogenous mechanism(s) of protection similar to that induced by ischemic preconditioning. Preservation of myocardial ATP, abolishing purine release, attenuation of free radical production, activation of adenosine receptors and KATP channels, and induction of heat shock proteins are common responses to ischemic and nonischemic stimuli of preconditioning. Although a significant reduction in myocardial infarction is critical to myocardial salvage and patient survival, it is equally important to have a functioning heart that can sustain systemic pressure without inotropic support or assist devices. It is scientifically challenging and clinically important to elucidate the mechanisms of myocardial preconditioning. However, it is necessary to expand the definition of myocardial preconditioning to include nonischemic stimuli of preconditioning and other important monitors of myocardial protection such as ventricular function and electrophysiological stability in addition to that of infarction. PMID:7579831

Abd-Elfattah, A S; Wechsler, A S

1995-07-01

339

Impact of hypertension on distal embolization, myocardial perfusion, and mortality in patients with ST segment elevation myocardial infarction undergoing primary angioplasty.  

PubMed

Hypertension is a well-known risk factor for atherosclerosis. However, data on the impact of hypertension in patients with ST elevation myocardial infarction (STEMI) are inconsistent and mainly related to studies performed in the thrombolytic era, with very few data on patients undergoing primary angioplasty. The aim of the present study was to evaluate the impact of hypertension on distal embolization, myocardial perfusion, and mortality in patients with STEMI undergoing primary percutaneous coronary intervention. Our population is represented by 1,662 patients undergoing primary angioplasty for STEMI included in the Early Glycoprotein IIb-IIIa inhibitors in Primary angioplasty database. Myocardial perfusion was evaluated by myocardial blush grade and ST segment resolution. Follow-up data were collected within 1 year after primary angioplasty. Hypertension was observed in 700 patients (42.1%). Hypertension was associated with more advanced age (p <0.001), female gender (p <0.001), diabetes (p <0.001), hypercholesterolemia (p <0.001), previous revascularization (p <0.001), anterior myocardial infarction (p = 0.006), longer ischemia time (p = 0.03), more extensive coronary artery disease (p = 0.002), more often treated with abciximab (p <0.001), and less often smokers (p <0.001). Hypertension was associated with impaired postprocedural myocardial blush grade 2 to 3 (68.2% vs 74.2%, p = 0.019) and complete ST segment resolution (51.7% vs 61.1%, p = 0.001). By a mean follow-up of 206 ± 158 days, 70 patients (4.3%) had died. Hypertension was associated with a greater mortality (6.2% vs 2.9%, hazard ratio 2.31, 95% confidence interval 1.42 to 3.73, p <0.001), confirmed after correction for baseline confounding factors (hazard ratio 1.82, 95% confidence interval 1.03 to 3.22, p <0.001). In conclusion, this study showed that among patients with STEMI undergoing primary angioplasty, hypertension is associated with impaired reperfusion and independently predicts 1-year mortality. PMID:23910428

De Luca, Giuseppe; van't Hof, Arnoud W J; Huber, Kurt; Gibson, C Michael; Bellandi, Francesco; Arntz, Hans-Richard; Maioli, Mauro; Noc, Marko; Zorman, Simona; Zeymer, Uwe; Gabriel, H Mesquita; Emre, Ayse; Cutlip, Donald; Rakowski, Tomasz; Gyongyosi, Maryann; Dudek, Dariusz

2013-10-15

340

Different effects of tirofiban and aspirin plus clopidogrel on myocardial no-reflow in a mini-swine model of acute myocardial infarction and reperfusion  

PubMed Central

Objective To compare the effects of an aspirin–clopidogrel combination with those of the specific glycoprotein IIb/IIIa inhibitor tirofiban on myocardial no?reflow, nitric oxide concentration and activity of nitric oxide synthase (NOS) isoforms in a mini?swine model of acute myocardial infarction and reperfusion. Methods Area of no?reflow was determined by both myocardial contrast echocardiography and pathological means in 40 mini?swine randomly assigned to five study groups: eight controls, eight pretreated with aspirin–clopidogrel combination for three days, eight given an intravenous infusion of tirofiban, eight treated with ischaemic preconditioning and eight sham operated. The acute myocardial infarction and reperfusion model was created with 3?h occlusion of the left anterior descending coronary artery followed by 1?h reperfusion. Results Compared with the control group, tirofiban significantly decreased the area of no?reflow assessed echocardiographically and pathologically, from 78.5% to 22.8% and 82.3% to 23.2%, respectively (both p??0.05) except for decreasing inducible NOS activity from 0.76 to 0.39?U/mg protein (p?myocardial no?reflow; in contrast, aspirin–clopidogrel combination is totally ineffective. These findings also support the concept that endothelial protection, apart from platelet inhibition, contributes to the beneficial effect of tirofiban on myocardial no?reflow. PMID:16387825

Yang, Y-J; Zhao, J-L; You, S-J; Wu, Y-J; Jing, Z-C; Yang, W-X; Meng, L; Wang, Y-W; Gao, R-L

2006-01-01

341

Determination of the Role of Oxygen in Suspected Acute Myocardial Infarction by Biomarkers  

ClinicalTrials.gov

Acute Myocardial Infarction (AMI); Acute Coronary Syndrome (ACS); ST Elevation (STEMI) Myocardial Infarction; Ischemic Reperfusion Injury; Non-ST Elevation (NSTEMI) Myocardial Infarction; Angina, Unstable

2014-11-08

342

Myocardial ischemia-mediated excitatory reflexes: a new function for thromboxane A2?  

PubMed

Clinical and experimental evidence has shown that myocardial ischemia activates cardiac spinal afferents that mediate sympathoexcitatory reflex responses. During myocardial ischemia, thromboxane A2 (TxA2) is released in large quantities by activated platelets in the coronary circulation of patients with coronary artery disease. We hypothesized that endogenous TxA2 contributes to sympathoexcitatory reflexes during myocardial ischemia through stimulation of TxA2/prostaglandin endoperoxide (TP) receptors. Regional myocardial ischemia was induced by occlusion of a diagonal branch of left anterior descending coronary artery of anesthetized cats. Hemodynamic parameters and renal sympathetic nerve activity were recorded after sinoaortic denervation and bilateral vagotomy. Regional myocardial ischemia evoked significant increases in mean blood pressure (122+/-10 vs. 139+/-12 mmHg, before vs. ischemia), aortic flow (153+/-18 vs. 167+/-20 ml/min), first derivative of left ventricular pressure at 40-mmHg developed pressure (2,736+/-252 vs. 2,926+/-281 mmHg/s), systemic vascular resistance (0.6+/-0.1 vs. 0.9+/-0.12 peripheral resistance units), and renal sympathetic nerve activity (by 22%). The reflex nature of the excitatory responses was confirmed by observing its disappearance after blockade of cardiac nerve transmission with intrapericardial 2% procaine treatment. Moreover, application of U-46619 (2.5-10 microg), a TxA2 mimetic, on the heart caused graded increases in mean arterial pressure and renal nerve activity, responses that were abolished 3 min after local blockade of cardiac neural transmission with intrapericardial procaine. BM 13,177 (30 mg/kg iv), a selective TP receptor antagonist, eliminated the reflex responses to U-46619 and significantly attenuated the excitatory responses during brief (5 min) regional myocardial ischemia. The sympathoexcitatory reflex responses to U-46619 were unchanged by blockade of histamine H1 receptors with pyrilamine and serotonin 5-HT3 receptors with tropisetron, indicating specificity of this TP receptor agonist. These data indicate that endogenous TxA2 participates in myocardial ischemia-mediated sympathoexcitatory reflex responses through a TP receptor mechanism. PMID:18952714

Fu, Liang-Wu; Phan, Andrew; Longhurst, John C

2008-12-01

343

The Effects of Nitroglycerin on Coronary Collaterals and Myocardial Contractility  

PubMed Central

Nitroglycerin (TNG) causes a prolonged dilatation of coronary collaterals. To demonstrate a functional significance of this dilatation we measured the effect of TNG on myocardial contractile force in dogs 2½-4 wk after the left anterior descending coronary artery (LAD) had been embolized in closed-chest animals. Development of collaterals was documented by angiography. Via a left thoracotomy the main left coronary artery (LCA) and LAD distal to the embolized plug were cannulated. Coronary flow and perfusion pressure were recorded. Contractile force was measured with gauges sutured to epicardial areas supplied by the left circumflex coronary artery (LCf) and occluded LAD. Coronary perfusion pressure in the LCA was gradually decreased until the contractile force recorded by the LAD gauge diminished while the LCf gauge was unaffected. Under these conditions, with coronary perfusion pressure held constant with the aid of a Starling resistance, TNG (18 ?g) injected into the LCA increased peripheral LAD pressure by 3-12 mm Hg and contractile force in the LAD region by 36% (range 20-90%), returning it to near-normal levels, while having minimal effect in the LCf area. These changes persisted for 5 min. When LCf and LAD areas were both ischemic, intracoronary TNG had minimal effect on peripheral LAD pressure and contractile force. Thus, TNG causes prolonged dilatation of coronary collaterals and presumed increased collateral flow with subsequent enhancement of myocardial contractile force in ischemic areas. This effect is seen only when ischemia is limited to an area supplied by the collaterals. When the whole heart is ischemic, collaterals are unresponsive to TNG, suggesting that these collaterals dilate fully when the regions from which they originate become ischemic. PMID:4201267

Cohen, Michael V.; Downey, James M.; Sonnenblick, Edmund H.; Kirk, Edward S.

1973-01-01

344

Prenatal diagnosis of anterior sacral meningocele.  

PubMed

Anterior sacral meningocele is an extremely rare condition and there has been only one previous report of a prenatal diagnosis. We report the case of a 36-year-old primigravida who was referred following detection of a huge fetal pelvic cyst on routine ultrasound examination at 19 + 4 weeks' gestation. Neither fetal ultrasound nor magnetic resonance imaging (MRI) at 20 + 5 weeks' gestation could detect communication between the cyst and the spinal cord. Because extension of the pear-shaped cyst through the pelvic diaphragm down to the perineum was reminiscent of dilated vagina and uterine cervix, a tentative diagnosis of hydrometrocolpos secondary to imperforate hymen was considered. On follow-up MRI at 33 + 5 weeks' gestation, a narrow stalk connecting the pelvic cyst and the spinal canal through the anterior sacral foramen was clearly delineated, allowing us to reach the prenatal diagnosis of anterior sacral meningocele. PMID:20882559

Sumi, A; Sato, Y; Kakui, K; Tatsumi, K; Fujiwara, H; Konishi, I

2011-04-01

345

Sexual dimorphism of anterior sacral curvature.  

PubMed

This study assesses the predictive value of anterior sacral curvature for sex estimation from skeletonized remains. Sacra from a sample of 125 American adults of known age and sex were examined. Nine measurements describing anterior sacral curvature were used in the analysis. Statistical treatment of the data included univariate statistics and discriminant function analysis for sex classification. A bootstrap validation method was employed to assess the classification error rates. Sacral curvature was significantly greater in men than in women at the level of the S2-S3 and S3-S4 articulations (p<0.05). Correct classification estimates for the discriminant function range from 66-72%. Although sexually dimorphic, metric observations of sacral curvature are not as reliable at predicting sex as other skeletal elements. Anterior sacral curvature should only be used for sex estimation in the absence of other, more reliable, indicators. PMID:20487142

Plochocki, Jeffrey H

2011-01-01

346

Acute effects of delayed reperfusion following myocardial infarction: a 3D x-ray imaging analysis  

NASA Astrophysics Data System (ADS)

Clinical and experimental data suggest that delayed reperfusion of the infarct related artery may limit infarct expansion without increasing myocardial salvage. In order to assess the potential mechanisms involved, an acute closed chest canine model of myocardial infarction and delayed reperfusion was studied. Nineteen dogs underwent 3D computed tomography in the Dynamic Spatial Reconstructor (a fast, volume imaging, CT scanner) at baseline and three and four hours later to estimate left ventricular chamber volumes, global distensibility and regional myocardial stiffness. A control group was scanned without intervention. An occlusion group underwent four hours of coronary artery occlusion. A reperfusion group underwent three hours of coronary artery occlusion followed by one hour of reperfusion. Similar infarct sizes were seen in the occlusion and reperfusion groups. Globally reperfusion was associated with increased left ventricular end diastolic pressure and prolongation of global relaxation. Regionally reperfusion was associated with increased myocardial stiffness, intramyocardial blood volume and wall thickness within the infarct zone relative to the not reperfused myocardium.

Simari, Robert D.; Bell, M. R.; Pao, Y. C.; Gersh, B. J.; Ritman, Erik L.

1996-04-01

347

Immunosuppressive therapy in patients with congestive cardiomyopathy and myocardial uptake of gallium-67  

SciTech Connect

Thirty-nine patients with idiopathic congestive cardiomyopathy underwent gallium-67 scintigraphy. Twenty had no evidence of myocardial uptake (group I) and 19 had demonstrable myocardial gallium-67 activity (group II). There was no significant difference in age, sex, duration of symptoms, antecedent viral illness, left ventricular end-diastolic pressure, pulmonary artery systolic pressure, or ejection fraction between the two groups. Fifteen patients in group II were treated with prednisone and azathioprine for a minimum of 8 months. Nine of 15 patients were clinically unchanged and gallium-67 scans remained positive (group IIa). Six patients had significant improvement and resolution of myocardial gallium-67 uptake (group IIb). The mean change in ejection fraction was +0.2% in group I, -4.8% in Group IIa, and +13.8% in group IIb. There were five deaths in group I (25% mortality), three in group IIa (33% mortality), and no deaths in group IIb. The only significant difference between patients in group IIa and those in group IIb was a greater left ventricular posterior wall thickness in group IIa patients. Twenty control patients without cardiac disease had negative gallium-67 scans. We conclude that gallium-67 myocardial scintigraphy may be a useful test for predicting the response to prednisone and azathioprine therapy.

O'Connell, J.B.; Robinson, J.A.; Henkin, R.E.; Gunnar, R.M.

1981-10-01

348

Immunosuppressive therapy in patients with congestive cardiomyopathy and myocardial uptake of Gallium-67  

SciTech Connect

Thirty-nine patients with idiopathic congestive cardiomyopathy underwent gallium-67 scintigraphy. Twenty had no evidence of myocardial uptake (group I) and 19 had demonstrable myocardial gallium-67 activity (group II). There was no significant difference in age, sex, duration of symptoms, antecedent viral illness, left ventricular end-diastolic pressure, pulmonary artery systolic pressure, or ejection fraction between the two groups. Fifteen patients in group II were treated with prednisone and azathioprine for a minimum of 8 months. Nine of 15 patients were clinically unchanged and gallium-67 scans remained positive (group IIa). Six patients had significant improvement and resolution of myocardial gallium-67 uptake (group IIb). The mean change in ejection fraction was +0.2% in group I, -4.8% in Group IIa, and +13.8% in group IIb. There were five deaths in group I (25% mortality), three in group IIa (33% mortality), and no deaths in group IIb. The only significant difference between patients in group IIa and those in group IIb was a greater left ventricular posterior wall thickness in group IIa patients. Twenty control patients without cardiac disease had negative gallium-67 scans. We conclude that gallium-67 myocardial scintigraphy may be a useful test for predicting the response to prednisone and azathioprine therapy.

O'Connell, J.B.; Robinson, J.A.; Henkin, R.E.; Gunnar, R.M.

1981-10-01

349

Isolated Abdominal Wall Metastasis of Endometrial Carcinoma  

PubMed Central

A woman in her mid-60s presented with a bulky mass on the anterior abdominal wall. She had a previous incidental diagnosis of endometrial adenocarcinoma FIGO stage IB following a vaginal hysterectomy. Physical exam and imaging revealed a well circumscribed bulging tumour at the umbilical region, measuring 10 × 9 × 9?cm, with overlying intact skin and subcutaneous tissue. Surgical resection was undertaken, and histological examination showed features of endometrial carcinoma. She began chemotherapy and is alive with no signs of recurrent disease one year after surgery. This case brings up to light an atypical location of a solitary metastasis of endometrial carcinoma.

Simoes, Jorge; Goncalves, Matilde; Matos, Isabel

2014-01-01

350

Spontaneous coronary artery dissection: a neglected cause of acute myocardial ischaemia and sudden death.  

PubMed Central

Spontaneous coronary artery dissection is a rare cause of acute myocardial ischaemia. Eight consecutive fatal cases which occurred in women aged 34-54 years (mean 43) are described. The dissection involved the left anterior descending coronary artery in four, the left main trunk in two, the right coronary artery in one, and both left anterior descending and circumflex arteries in one. The clinical presentation was sudden death in six cases, and acute myocardial infarction in two. Diagnosis was made at necropsy in every case but one, in which coronary dissection was diagnosed during life by selective coronary angiography. The only ascertained risk factor was hypertension in one patient; none of the women was in the puerperium, and Marfan syndrome was excluded in all. Histology showed a haematoma between the coronary tunica media and adventitia, that flattened and occluded the lumen; a coronary intimal tear was detected in only two cases. Unusual histological findings were cystic medial necrosis in one case, eosinophilic inflammatory infiltrates in four, and angiomatosis of the tunica adventitia in one. Patients dying of spontaneous coronary dissection are usually middle aged women, with no coronary atherosclerosis and apparently no risk factors. Spontaneous coronary artery dissection is unpredictable, and sudden death is the usual mode of clinical presentation. Prompt diagnosis and life saving treatment is far from being achieved. Images PMID:8665336

Basso, C.; Morgagni, G. L.; Thiene, G.

1996-01-01

351

The importance of sex-specific quantitative criteria in thallium-201 myocardial scintigraphy  

SciTech Connect

Breast attenuation is an important cause of artifactual cold spots on visually interpreted TL-201 myocardial images. This study was undertaken to determine the need for sex-specific criteria in the quantitative analysis of exercise-redistribution TL-201 myocardial scintigraphy (SCINT). The studies of 13 normal females (F) and 12 normal males (M) were processed according to the method of a previous study. Significant sexual differences were found in 7/12 regional uptake (U) proportions, 9/11 regional washout (WO) percentages, 0/3 image redistribution indices, and 0/1 lung to heart ratio. The differences primarily reflected a proportionately decreased anterior and septal uptake in F, a proportionately decreased inferior and inferoapical U in M, and faster WO in F. Sex-specific and total population normal boundaries were set a +- 3SD of the mean for each parameter. Sex-specific boundaries were narrower, and, for 5 parameters (4U and 1WO), contained within the total population boundaries. It was estimated that these differences in boundaries would result in a 6 to 25% discrepancy in patient classification. These results predict that a subset of M and F with coronary artery stenoses could be misclassified as normal by total population criteria, while properly classified as abnormal by sex-specific criteria. The authors conclude that since important differences exist between M and F in the detected pattern of TL-201 myocardial U and WO, sex-specific cr4iteria may enhance the predictive accuracy of SCINT.

Rabinovitch, M.A.; Suissa, S.; Elstein, J.; Turek, M.; Addas, A.; Burgess, J.H.; Rosenthall, L.

1984-01-01

352

Thallium scintigraphy in human transplants: A way to detect myocardial damage  

SciTech Connect

An original index has been derived from thallium images to detect histopathologic changes in heart transplant patients. One hundred eighty-four static and end-diastolic images with thallium were recorded 5 minutes after injection in the left anterior oblique projection. Twenty patients and 14 healthy volunteers were studied. The epicardial and endocardial borders were determined, and the difference of these values was considered the myocardial area. The results in heart transplants were compared with the results of endomyocardial biopsies (N = 142). A significant decrease (p less than 0.01) was found in the index of the myocardial area between normal biopsy results and mild and moderate rejection. Differences were not detected between studies performed in several postoperative periods in the absence of rejection. The results in healthy volunteers prove that the index does not change between studies performed at different times in the same subject, although the value obtained from the end-diastolic image was more constant. On the basis of these results, it is possible to suggest that the decrease in the myocardial area during rejection is the result of a fall of thallium uptake by the myocardium. Capillary endothelial hyperplasia, perivascular infiltration, and myocytolysis can justify these changes, although the presence of other histologic findings, such as intramyocardial edema, could influence the value of this index. We conclude that the uptake of thallium decreases during acute rejection episodes; the results obtained from the images, in this work, are an expression of this event.

Richter, J.; Herreros, J.; Serena, A.; Domper, M.; Ramirez, J.C.; Arcas, R. (Universidad de Navarra, Pamplona (Spain))

1991-01-01

353

Measurement of myocardial infarction fraction using single photon emission computed tomography  

SciTech Connect

Although infarct size correlates generally with prognosis after acute myocardial infarction, an absolute measure of infarct size may have differing prognostic significance depending on absolute left ventricular mass. To test the hypothesis that single photon emission computed tomography can accurately measure myocardial infarct size as a percent of total left ventricular mass (''infarction fraction''), thallium-201 and technetium-99m pyrophosphate tomograms were acquired in 21 dogs 24 to 48 hours after fixed occlusion of the left anterior descending or circumflex coronary artery. Pathologic infarct weight was measured as the myocardial mass that showed no staining with triphenyltetrazolium chloride. Scintigraphic infarct mass by technetium-99m pyrophosphate was calculated from the total number of left ventricular volume elements (voxels) demonstrating technetium-99m pyrophosphate uptake X voxel dimension (( 0.476 cm)3) X specific gravity of myocardium (1.05 g/cm3). Scintigraphic left ventricular mass was calculated in a similar fashion using an overlay of the thallium-201 and technetium-99m pyrophosphate scans. The ''infarction fraction'' was calculated as: infarction fraction = infarct mass/left ventricular mass. There was good correlation between single photon emission computed tomography and pathologic measurements of infarct mass, left ventricular mass, and ''infarction fraction''.

Wolfe, C.L.; Lewis, S.E.; Corbett, J.R.; Parkey, R.W.; Buja, L.M.; Willerson, J.T.

1985-07-01

354

Real-time intraoperative visualization of myocardial circulation using augmented reality temperature display.  

PubMed

For direct visualization of myocardial ischemia during cardiac surgery, we tested the feasibility of presenting infrared (IR) tissue temperature maps in situ during surgery. A new augmented reality (AR) system, consisting of an IR camera and an integrated projector having identical optical axes, was used, with a high resolution IR camera as control. The hearts of five pigs were exposed and an elastic band placed around the middle of the left anterior descending coronary artery to induce ischemia. A proximally placed ultrasound Doppler probe confirmed reduction of flow. Two periods of complete ischemia and reperfusion were studied in each heart. There was a significant decrease in IR-measured temperature distal to the occlusion, with subsequent return to baseline temperatures after reperfusion (baseline 36.9 ± 0.60 (mean ± SD) versus ischemia 34.1 ± 1.66 versus reperfusion 37.4 ± 0.48; p < 0.001), with no differences occurring in the non-occluded area. The AR presentation was clear and dynamic without delay, visualizing the temperature changes produced by manipulation of the coronary blood flow, and showed concentrically arranged penumbra zones during ischemia. Surface myocardial temperature changes could be assessed quantitatively and visualized in situ during ischemia and subsequent reperfusion. This method shows potential as a rapid and simple way of following myocardial perfusion during cardiac surgery. The dynamics in the penumbra zone could potentially be used for visualizing the effect of therapy on intraoperative ischemia during cardiac surgery. PMID:22772435

Szabó, Zoltán; Berg, Sören; Sjökvist, Stefan; Gustafsson, Torbjörn; Carleberg, Per; Uppsäll, Magnus; Wren, Joakim; Ahn, Henrik; Smedby, Örjan

2013-02-01

355

Evaluation of myocardial involvement in muscular dystrophy with Thallium-201 emission computed tomography  

SciTech Connect

The clinical usefulness of quantitative analysis of thallium-201 emission computed tomography (ECT) for evaluation of left ventricular myocardial fibrosis was assessed on 45 patients with Duchenne(D), facioscapulohumeral(FSH), limbgirdle(LG) and myotonic(M) dystrophy. Trans-,long- and short-axial images were interpreted quantitatively using circumferential profile analysis, and the fibrotic tissue size (%FIB) was estimated by integration of hypoperfused areas in 6 to 8 consecutive short-axial slices. Lung/mediastinum count ratios (L/M ratio) were also assessed. Distinct ECT defects were found in 42 patients (all cases of D, FSH and LG, and 2 of 5 MTs). ECT defects were observed specifically in the posterolateral wall (71%) and apex (58%) in D, and were scattered in all LV walls in FSHG, LG and MT. ECG and VCG underestimated the extent of myocardial fibrosis in 17 patients (40%). Percent FIBs coincided with fibrotic tissue sizes proven by autopsy. Body-surface ECG should be influenced by cardiac position and rotation in the thorax, which were often observed in these disease entities. These factors were also assessed with ECT. The authors conclude; ECT to be useful for non-invasive evaluation of myocardial fibrosis in patients with various types of muscular dystrophy.

Yamamoto, S.; Kawai, N.; Matsushima, H.; Okada, M.; Yamauchi, K.; Yokota, M.; Hayashi, H.; Sotobata, I.; Sakuma, S.

1985-05-01

356

Effect of cold air inhalation and isometric exercise on coronary blood flow and myocardial function in humans  

PubMed Central

The effects of cold air inhalation and isometric exercise on coronary blood flow are currently unknown, despite the fact that both cold air and acute exertion trigger angina in clinical populations. In this study, we used transthoracic Doppler echocardiography to measure coronary blood flow velocity (CBV; left anterior descending coronary artery) and myocardial function during cold air inhalation and handgrip exercise. Ten young healthy subjects underwent the following protocols: 5 min of inhaling cold air (cold air protocol), 5 min of inhaling thermoneutral air (sham protocol), 2 min of isometric handgrip at 30% of maximal voluntary contraction (grip protocol), and 5 min of isometric handgrip at 30% maximal voluntary contraction while breathing cold air (cold + grip protocol). Heart rate, blood pressure, inspired air temperature, CBV, myocardial function (tissue Doppler imaging), O2 saturation, and pulmonary function were measured. The rate-pressure product (RPP) was used as an index of myocardial O2 demand, whereas CBV was used as an index of myocardial O2 supply. Compared with the sham protocol, the cold air protocol caused a significantly higher RPP, but there was a significant reduction in CBV. The cold + grip protocol caused a significantly greater increase in RPP compared with the grip protocol (P = 0.045), but the increase in CBV was significantly less (P = 0.039). However, myocardial function was not impaired during the cold + grip protocol relative to the grip protocol alone. Collectively, these data indicate that there is a supply-demand mismatch in the coronary vascular bed when cold ambient air is breathed during acute exertion but myocardial function is preserved, suggesting an adequate redistribution of blood flow. PMID:21940852

Muller, Matthew D.; Gao, Zhaohui; Drew, Rachel C.; Herr, Michael D.; Leuenberger, Urs A.

2011-01-01

357

Repetitive myocardial infarctions secondary to delirium tremens.  

PubMed

Delirium tremens develops in a minority of patients undergoing acute alcohol withdrawal; however, that minority is vulnerable to significant morbidity and mortality. Historically, benzodiazepines are given intravenously to control withdrawal symptoms, although occasionally a more substantial medication is needed to prevent the devastating effects of delirium tremens, that is, propofol. We report a trauma patient who required propofol sedation for delirium tremens that was refractory to benzodiazepine treatment. Extubed prematurely, he suffered a non-ST segment myocardial infarction followed by an ST segment myocardial infarction requiring multiple interventions by cardiology. We hypothesize that his myocardial ischemia was secondary to an increased myocardial oxygen demand that occurred during his stress-induced catecholamine surge during the time he was undertreated for delirium tremens. This advocates for the use of propofol for refractory benzodiazepine treatment of delirium tremens and adds to the literature on the instability patients experience during withdrawal. PMID:25197580

Schwartzberg, David; Shiroff, Adam

2014-01-01

358

Microcirculatory Disturbances and Human Myocardial Infarction.  

National Technical Information Service (NTIS)

Thirty-nine cases of thrombotic thrombocytopenic purpura (Moschcowitz's disease) were examined, and the severe, obstructive involvement of the intramyocardial arterial branches was compared to the myocardial condition. In only 4 cases (10.2 per cent) was ...

G. Baroldi, W. C. Manion

1966-01-01

359

Myocardial tissue characterization with magnetic resonance imaging.  

PubMed

The availability of an accurate, noninvasive method using cardiac magnetic resonance imaging (MRI) to distinguish microscopic myocardial tissue changes at a macroscopic scale is well established. High-resolution in vivo monitoring of different pathologic tissue changes in the heart is a useful clinical tool for assessing the nature and extent of cardiac pathology. Cardiac MRI utilizes myocardial signal characteristics based on relaxation parameters such as T1, T2, and T2 star values. Identifying changes in relaxation time enables the detection of distinctive myocardial diseases such as cardiomyopathies and ischemic myocardial injury. The presented state-of-the-art review paper serves the purpose of introducing and summarizing MRI capability of tissue characterization in present clinical practice. PMID:24394716

Sharma, Vishal; Binukrishnan, Sukumaran; Schoepf, U Joseph; Ruzsics, Balazs

2014-11-01

360

Improved exercise myocardial perfusion during lidoflazine therapy  

SciTech Connect

Lidoflazine is a synthetic drug with calcium-channel blocking effects. In a study of 6 patients with severe classic angina pectoris, single-blind administration of lidoflazine was associated with improved myocardial perfusion during exercise as determined by thallium-201 stress scintigraphy. These studies demonstrate that lidoflazine therapy is associated with relief of angina, an increased physical work capacity, and improved regional myocardial perfusion during exercise.

Shapiro, W.; Narahara, K.A.; Park, J.

1983-11-01

361

Bone Marrow Cells and Myocardial Regeneration  

Microsoft Academic Search

Hematopoietic stem cell (HSC) plasticity and its clinical application have been studied profoundly in the past few years.\\u000a Recent investigations indicate that HSC and other bone marrow stem cells can develop into other tissues. Because of the high\\u000a morbidity and mortality of myocardial infarction and other heart disorders, myocardial regeneration is a good example of the\\u000a clinical application of HSC

Fu-sheng Wang; Cathy Trester

2004-01-01

362

Abdominal wall surgery  

MedlinePLUS

Abdominal wall surgery is surgery that improves the appearance of flabby, stretched-out abdominal (belly) muscles and skin. It ... tummy tuck" to more complicated, extensive surgery. Abdominal wall surgery is not the same as liposuction, which ...

363

Strain Inhomogeneity in the Anterior Cruciate Ligament  

E-print Network

be needed to predict injury ofthe anterior cruciate ligament (ACL), Richmond, CA 94804 this work tested the application ofa number of loads important to injury etiology of the ACL. To provide the data for testing, moments, quadriceps, and hamstrings forces. Various combinations of these loads Davis, CA 95616 were also

Hull, Maury

364

Retrograde Amnesia Following Anterior Thalamic Infarction  

Microsoft Academic Search

Background : Retrograde amnesia (RA) refers to the failure to recall events that occurred before a brain injury. RA is known to be associated with brain lesions involving the hippocampus, entorhinal cortex and the frontal lobe. Anterior thalamic lesion often causes anterograde amnesia but rarely causes RA. The aim of the present study is in two parts . First, we

Jee-Young Oh; Jay C. Kwon; Juhee Chin; Jae-Hong Lee; Kyoung-Gyu Choi; Kee-Duk Park; Yong Jeong; Duk L. Na

2002-01-01

365

Chlamydia in Anterior Ischemic Optic Neuropathy  

Microsoft Academic Search

There is an increasing body of evidence linking the common respiratory human pathogen Chlamydia pneumoniae with atherosclerosis and other vascular disorders. Our research was designed to investigate the association of this organism with anterior ischemic optic neuropathy (AION), representing an acute ischemic disorder of the optic nerve head. Sera were examined of 14 consecutive patients with AION and of 14

Pia V. Vécsei; Karl Kircher; Andreas Reitner; Gelas Khanakha; Gerold Stanek

2002-01-01

366

Quadriceps protects the anterior cruciate ligament  

Microsoft Academic Search

The aim of this study is to show that the quadriceps is the primary muscular restraint to anterior tibial translation during closed kinetic chain activities such as running, jumping, walking, and standing. It is my hypothesis that the quadriceps vector is directed superiorly during open kinetic chain knee extension and inferiorly during closed kinetic chain knee extension. My methods involve

Marko Bodor

2001-01-01

367

Novel adjunctive treatments of myocardial infarction.  

PubMed

Myocardial infarction is a major cause of death and disability worldwide and myocardial infarct size is a major determinant of prognosis. Early and successful restoration of myocardial reperfusion following an ischemic event is the most effective strategy to reduce final infarct size and improve clinical outcome, but reperfusion may induce further myocardial damage itself. Development of adjunctive therapies to limit myocardial reperfusion injury beyond opening of the coronary artery gains increasing attention. A vast number of experimental studies have shown cardioprotective effects of ischemic and pharmacological conditioning, but despite decades of research, the translation into clinical effects has been challenging. Recently published clinical studies, however, prompt optimism as novel techniques allow for improved clinical applicability. Cyclosporine A, the GLP-1 analogue exenatide and rapid cooling by endovascular infusion of cold saline all reduce infarct size and may confer clinical benefit for patients admitted with acute myocardial infarcts. Equally promising, three follow-up studies of the effect of remote ischemic conditioning (RIC) show clinical prognostic benefit in patients undergoing coronary surgery and percutaneous coronary intervention. The discovery that RIC can be performed noninvasively using a blood pressure cuff on the upper arm to induce brief episodes of limb ischemia and reperfusion has facilitated the translation of RIC into the clinical arena. This review focus on novel advances in adjunctive therapies in relation to acute and elective coronary procedures. PMID:24976915

Schmidt, Michael Rahbek; Pryds, Kasper; Bøtker, Hans Erik

2014-06-26

368

Effect of eating on thallium myocardial imaging  

SciTech Connect

To determine if eating between initial and delayed thallium images alters the appearance of the delayed thallium scan, a prospective study was performed; 184 subjects sent for routine thallium imaging were randomized into two groups, those who ate a meal high in carbohydrates between initial and delayed thallium myocardial images (n = 106), and those who fasted (n = 78). The /sup 201/Tl images were interpreted in blinded fashion for global myocardial and pulmonary clearance of /sup 201/Tl myocardial defects. The eating group had a significantly lower incidence of transient myocardial defects compared to the noneating group (7 percent vs 18 percent, respectively; p less than 0.05). The time between initial and delayed images and the incidence of exercise-induced ischemic ST-segment depression or pathologic Q waves on the electrocardiogram were not significantly different between the two groups. These data suggest that eating a high-carbohydrate meal between initial and delayed /sup 201/Tl images causes increased /sup 201/Tl myocardial clearance rates and may alter /sup 201/Tl myocardial redistribution over time.

Wilson, R.A.; Sullivan, P.J.; Okada, R.D.; Boucher, C.A.; Morris, C.; Pohost, G.M.; Strauss, H.W.

1986-02-01

369

Skyrmion Multi-Walls  

E-print Network

Skyrmion walls are topologically-nontrivial solutions of the Skyrme system which are periodic in two spatial directions. We report numerical investigations which show that solutions representing parallel multi-walls exist. The most stable configuration is that of the square $N$-wall, which in the $N\\to\\infty$ limit becomes the cubically-symmetric Skyrme crystal. There is also a solution resembling parallel hexagonal walls, but this is less stable.

J. Silva Lobo; R. S. Ward

2009-10-28

370

Observing Stone Walls  

NSDL National Science Digital Library

In this lesson, students will learn why and how stone walls were built. A prior knowledge of New England colonists and the history of New England is helpful. After a directed reading and discussion, they will take a nature walk to an area where they can examine a stone wall. The students will then use notebook and pencil to sketch the wall and make observations of the stones, the plants growing nearby, and other materials they see around the wall.

371

Vortex formation and recirculation zones in left anterior descending artery stenoses: computational fluid dynamics analysis  

NASA Astrophysics Data System (ADS)

Flow patterns may affect the potential of thrombus formation following plaque rupture. Computational fluid dynamics (CFD) were employed to assess hemodynamic conditions, and particularly flow recirculation and vortex formation in reconstructed arterial models associated with ST-elevation myocardial infraction (STEMI) or stable coronary stenosis (SCS) in the left anterior descending coronary artery (LAD). Results indicate that in the arterial models associated with STEMI, a 50% diameter stenosis immediately before or after a bifurcation creates a recirculation zone and vortex formation at the orifice of the bifurcation branch, for most of the cardiac cycle, thus allowing the creation of stagnating flow. These flow patterns are not seen in the SCS model with an identical stenosis. Post-stenotic recirculation in the presence of a 90% stenosis was evident at both the STEMI and SCS models. The presence of 90% diameter stenosis resulted in flow reduction in the LAD of 51.5% and 35.9% in the STEMI models and 37.6% in the SCS model, for a 10 mmHg pressure drop. CFD simulations in a reconstructed model of stenotic LAD segments indicate that specific anatomic characteristics create zones of vortices and flow recirculation that promote thrombus formation and potentially myocardial infarction.

Katritsis, D. G.; Theodorakakos, A.; Pantos, I.; Andriotis, A.; Efstathopoulos, E. P.; Siontis, G.; Karcanias, N.; Redwood, S.; Gavaises, M.

2010-03-01

372

MIR wall surveyor  

Microsoft Academic Search

This report addresses the problem of determining the layer thickness of a wall probed with a monostatic, hand-held implementation of Lawrence Livermore National Laboratory's Micropower Impulse Radar (MIR). Our goal is to locate the layers of the wall, and measure its overall thickness. The physical constraints require the device to be held fixed or swept rapidly over the wall. Thus

1998-01-01

373

Consider the Walls  

ERIC Educational Resources Information Center

This article critically examines classroom walls from four perspectives: (1) reading the environment; (2) walls that silence; (3) the purpose of display; and (4) aesthetics. The author offers some suggestions for teachers to consider when purchasing materials and in planning how to use classroom walls to enhance the educational setting. She…

Tarr, Patricia

2004-01-01

374

Description of Stone Walls  

NSDL National Science Digital Library

This outline provides a list of key terms used to describe stone walls. The definitions for each term can be found in the corresponding chapter and section of the book 'Exploring Stone Walls'. Users can use the outline as a checklist, marking off the terms that best describe the wall they are investigating.

375

Human Uterine Wall Tension Trajectories and the Onset of Parturition  

PubMed Central

Uterine wall tension is thought to be an important determinant of the onset of labor in pregnant women. We characterize human uterine wall tension using ultrasound from the second trimester of pregnancy until parturition and compare preterm, term and twin pregnancies. A total of 320 pregnant women were followed from first antenatal visit to delivery during the period 2000–2004 at the John Hunter Hospital, NSW, Australia. The uterine wall thickness, length, anterior-posterior diameter and transverse diameter were determined by serial ultrasounds. Subjects were divided into three groups: women with singleton pregnancies and spontaneous labor onset, either preterm or term and women with twin pregnancies. Intrauterine pressure results from the literature were combined with our data to form trajectories for uterine wall thickness, volume and tension for each woman using the prolate ellipsoid method and the groups were compared at 20, 25 and 30 weeks gestation. Uterine wall tension followed an exponential curve, with results increasing throughout pregnancy with the site of maximum tension on the anterior wall. For those delivering preterm, uterine wall thickness was increased compared with term. For twin pregnancies intrauterine volume was increased compared to singletons (), but wall thickness was not. There was no evidence for increased tension in those delivering preterm or those with twin gestations. These data are not consistent with a role for high uterine wall tension as a causal factor in preterm spontaneous labor in singleton or twin gestations. It seems likely that hormonal differences in multiple gestations are responsible for increased rates of preterm birth in this group rather than increased tension. PMID:20585649

Sokolowski, Peter; Saison, Francis; Giles, Warwick; McGrath, Shaun; Smith, David; Smith, Julia; Smith, Roger

2010-01-01

376

Myocardial infarction size and location: a comparative study of epicardial isopotential mapping, thallium-201 scintigraphy, electrocardiography and vectorcardiography  

SciTech Connect

Based on epicardial isopotential mapping (the Ep Map), which was calculated from body surface isopotential mapping (the Body Map) with Yamashita's method, using the finite element technique, we predicted the location and size of the abnormal depolarized area (the infarcted area) in 19 clinical cases of anterior and 18 cases of inferoposterior infarction. The prediction was done using Toyama's diagnostic method, previously reported. The accuracy of the prediction by the Ep Map was assessed by comparing it with findings from thallium-201 scintigraphy (SCG), electrocardiography (ECG) and vectorcardiography (VCG). In all cases of anterior infarction, the location of the abnormal depolarized areas determined on the Ep Map, which was localized at the anterior wall along the anterior intraventricular septum, agreed with the location of the abnormal findings obtained by SCG, ECG and VCG. For all inferoposterior infarction cases, the abnormal depolarized areas were localized at the posterior wall and the location also coincided with that of the abnormal findings obtained by SCG, ECG and VCG. Furthermore, we ranked and ordered the size of the abnormal depolarized areas, which were predicted by the Ep Map for both anterior and inferoposterior infarction cases. In the cases of anterior infarction, the order of the size of the abnormal depolarized area by the Ep Map was correlated to the size of the abnormal findings by SCG, as well as to the results from Selvester's QRS scoring system in ECG and to the angle of the maximum QRS vector in the horizontal plane in VCG.

Toyama, S.; Suzuki, K.; Takahashi, T.; Yamashita, Y.

1987-07-01

377

The Role of Echocardiography in Coronary Artery Disease and Acute Myocardial Infarction  

PubMed Central

Echocardiography is a non-invasive diagnostic technique which provides information regarding cardiac function and hemodynamics. It is the most frequently used cardiovascular diagnostic test after electrocardiography and chest X-ray. However, in a patient with acute chest pain, Transthoracic Echocardiography is essential both for diagnosing acute coronary syndrome, zeroing on the evaluation of ventricular function and the presence of regional wall motion abnormalities, and for ruling out other etiologies of acute chest pain or dyspnea, including aortic dissection and pericardial effusion. Echocardiography is a versatile imaging modality for the management of patients with chest pain and assessment of left ventricular systolic function, diastolic function, and even myocardial and coronary perfusion and is, therefore, useful in the diagnosis and triage of patients with acute chest pain or dyspnea. This review has focused on the current applications of echocardiography in patients with coronary artery disease and myocardial infarction. PMID:23646042

Esmaeilzadeh, Maryam; Parsaee, Mozhgan; Maleki, Majid

2013-01-01

378

Measurement of anterior chamber diameter and biometry of anterior segment by Scheimpflug slitlamp photography  

SciTech Connect

Twenty-eight fresh donor eyes (Georgia Lions Eye Bank) ranging in age from four months to 87 years were used for an in vitro study to determine the feasibility of obtaining accurate anterior chamber diameter measurements with our Scheimpflug ultraviolet-visible slitlamp densitography apparatus. The in vivo study was performed on 16 hybrid monkeys (of varying age). These data were within 0.1 mm of measurements obtained with a modified paracentesis needle specially designed to obtain such measurements. The results of the foregoing study demonstrate that the Scheimpflug slitlamp photographic analyses can provide an accurate measurement of the anterior chamber diameter without entering the globe surgically. This will enable the surgeon to determine the diameter and order an anterior chamber IOL of a specified size prior to surgery. The authors have devised an automated program to analyze the negatives and provide direct anterior chamber diameter measurements.

Lerman, S.; Hockwin, O.

1985-03-01

379

Myocardial perfusion abnormalities in patients with hypertrophic cardiomyopathy: assessment with thallium-201 emission computed tomography  

SciTech Connect

Myocardial ischemia may play a critical role in the symptomatic presentation and natural history of hypertrophic cardiomyopathy (HCM). To assess the relative prevalence and functional significance of myocardial perfusion abnormalities in patients comprising the broad clinical spectrum of HCM, we studied 72 patients (ages 12 to 69 years, mean 40) using thallium-201 emission computed tomography. Imaging was performed immediately after maximal exercise and again after a 3 hr delay. Regional perfusion defects were identified in 41 of the 72 patients (57%). Fixed or only partially reversible defects were evident in 17 patients, 14 of whom (82%) had left ventricular ejection fractions of less than 50% at rest. Twenty-four patients demonstrated perfusion defects during exercise that completely reversed at rest; all had normal or hyperdynamic left ventricular systolic function (ejection fraction greater than or equal to 50%). Perfusion abnormalities were present in all regions of the left ventricle. However, the fixed defects were observed predominantly in segments of the left ventricular wall that were of normal or only mildly increased (15 to 20 mm) thickness; in contrast, a substantial proportion (41%) of the completely reversible defects occurred in areas of moderate-to-marked wall thickness (greater than or equal to 20 mm, p less than .001). Neither a history of chest pain nor its provocation with treadmill exercise was predictive of an abnormal thallium study, since regional perfusion defects were present in 10 of 18 (56%) completely asymptomatic patients, compared with 31 of 54 (58%) symptomatic patients. These data indicate that myocardial perfusion abnormalities occur commonly among patients with HCM. Fixed or only partially reversible defects suggestive of myocardial scar and/or severe ischemia occur primarily in patients with impaired systolic performance.

O'Gara, P.T.; Bonow, R.O.; Maron, B.J.; Damske, B.A.; Van Lingen, A.; Bacharach, S.L.; Larson, S.M.; Epstein, S.E.

1987-12-01

380

Radionuclide imaging of myocardial perfusion and viability in assessment of acute myocardial infarction  

SciTech Connect

Technical advances in radionuclide imaging have important implications for the management of patients with acute myocardial infarction. Single-photon emission computerized tomography with thallium 201 (TI-201) offers greater accuracy than planar imaging in detecting, localizing and sizing myocardial perfusion defects. Use of single-photon emission computerized tomography with TI-201 should allow for a more accurate assessment of prognosis after myocardial infarction. A new radiopharmaceutical, technetium 99-m methoxyisobutyl isonitrile, provides a number of advantages over TI-201, including higher quality images, lack of redistribution, and the ability to assess first-pass ventricular function. Applications of TI-201 and technetium 99-m methoxyisobutyl isonitrile include assessment of arterial patency and myocardial salvage immediately after thrombolytic therapy, detection of resting ischemia after thrombolytic therapy, targeting of subsets of patients for further intervention, and predischarge assessment to predict the future course of patients after an acute myocardial infarction.

Berman, D.S.; Kiat, H.; Maddahi, J.; Shah, P.K.

1989-07-18

381

Automatic detection of myocardial contours in cine-computed tomographic images  

SciTech Connect

Quantitative evaluation of cardiac function from cardiac images requires the identification of the myocardial walls. This generally requires the clinician to view the image and interactively trace the contours. This method is susceptible to great variability that depends on the experience and knowledge of the particular operator tracing the contours. The particular imaging modality that is used may also add tracing difficulties. Cine-computed tomography (cine-CT) is an imaging modality capable of providing high quality cross-sectional images of the heart. CT images, however, are cluttered. To decrease this variability, investigators have developed computer-assisted or near-automatic techniques for tracing these contours. All of these techniques, however, require some operator intervention to confidently identify myocardial borders. The authors present a new algorithm that automatically finds the heart within the chest, and then proceeds to outline the myocardial contours. Information at each tomographic slice is used to estimate the contours at the next tomographic slice, thus allowing the algorithm to work in near-apical cross-sectional images where the myocardial borders are often difficult to identify. The algorithm does not require operator input and can be used in a batch mode to process large quantities of data. An evaluation and correction phase is included to allow an operator to view the results and selectively correct portions of contours. They tested the algorithm by automatically identifying the myocardial borders of 27 cardiac images obtained from three human subjects and quantitatively comparing these automatically determined borders with those traced by an experienced cardiologist.

Philip, K.P.; Dove, E.L.; Stanford, W.; Chandran, K.B. (Univ. of Iowa, Iowa City, IA (United States). Dept. of Biomedical Engineering); McPherson, D.D.; Gotteiner, N.L.; Vonesh, M.J. (Northwestern Univ., Chicago, IL (United States). Dept. of Internal Medicine); Reed, J.E.; Rumberger, J.A. (Mayo Clinic, Rochester, MN (United States). Dept. of Cardiovascular Diseases)

1994-06-01

382

Allograft anterior tibialis tendon with bioabsorbable interference screw fixation in anterior cruciate ligament reconstruction  

Microsoft Academic Search

For a variety of reasons, bone–patellar tendon–bone and Achilles tendon allografts have been used more commonly in anterior cruciate ligament reconstruction. Soft-tissue allografts used mainly are the semitendinosus, gracilis, and occasionally the quadriceps tendons. The anterior tibialis tendon is a thick, strong tendon that can be prepared with one doubling of the graft, has a large cross-sectional area, and has

David N. M. Caborn; Jeffrey B. Selby

2002-01-01

383

Instrumented measurement of anterior knee laxity in patients with acute anterior cruciate ligament disruption  

Microsoft Academic Search

Instrumented anterior\\/posterior laxity measurements were performed on 138 patients evaluated within 2 weeks of injury with their first traumatic knee hemar throsis. All patients were tested with the MEDmetric Arthrometer model KT-1000 in a knee injury clinic. Seventy-five of the patients had knee arthroscopy. Thirty-three had arthrometer laxity tests under anes thesia. Eighty-seven percent of patients arthroscoped had anterior cruciate

Dale M. Daniel; Mary Lou Stone; Raymond Sachs; Lawrence Malcom

1985-01-01

384

Anterior opening wedge osteotomy of the proximal tibia for anterior knee pain in idiopathic hyperextension knees  

Microsoft Academic Search

We analysed 20 patients with 24 knees affected by idiopathic genu recurvatum who were treated with an anterior opening wedge osteotomy of the proximal tibia because of anterior knee pain. We managed to attain full satisfaction in 83% of the patients with a mean follow-up of 7.4 years. The mean Hospital for Special Surgery score was 90.3 (range 70.5–99.5), and

T. M. van Raaij; J. de Waal Malefijt

2006-01-01

385

Fluidized wall for protecting fusion chamber walls  

DOEpatents

Apparatus for protecting the inner wall of a fusion chamber from microexplosion debris, x-rays, neutrons, etc. produced by deuterium-tritium (DT) targets imploded within the fusion chamber. The apparatus utilizes a fluidized wall similar to a waterfall comprising liquid lithium or solid pellets of lithium-ceramic, the waterfall forming a blanket to prevent damage of the structural materials of the chamber.

Maniscalco, James A. (Danville, CA); Meier, Wayne R. (Livermore, CA)

1982-01-01

386

Photoacoustic tomography of ex vivo mouse hearts with myocardial infarction  

NASA Astrophysics Data System (ADS)

In the present study, we evaluated the applicability of ex vivo photoacoustic imaging (PAI) on small animal organs. We used photoacoustic tomography (PAT) to visualize infarcted areas within murine hearts and compared these data to other imaging techniques [magnetic resonance imaging (MRI), micro-computed tomography] and histological slices. In order to induce ischemia, an in vivo ligation of the left anterior descending artery was performed on nine wild-type mice. After varying survival periods, the hearts were excised and fixed in formaldehyde. Samples were illuminated with nanosecond laser pulses delivered by a Nd:YAG pumped optical parametric oscillator. Ultrasound detection was achieved using a Mach-Zehnder interferometer (MZI) working as an integrating line detector. The voxel data were computed using a Fourier-domain based reconstruction algorithm, followed by inverse Radon transforms. The results clearly showed the capability of PAI to visualize myocardial infarction and to produce three-dimensional images with a spatial resolution of approximately 120 ?m. Regions of affected muscle tissue in PAI corresponded well with the results of MRI and histology. Photoacoustic tomography utilizing a MZI for ultrasound detection allows for imaging of small tissue samples. Due to its high spatial resolution, good soft tissue contrast and comparatively low cost, PAT offers great potentials for imaging.

Holotta, Markus; Grossauer, Harald; Kremser, Christian; Torbica, Pavle; Völkl, Jakob; Degenhart, Gerald; Esterhammer, Regina; Nuster, Robert; Paltauf, Günther; Jaschke, Werner

2011-03-01

387

Diagnostic accuracy of thallium-201 myocardial perfusion imaging  

SciTech Connect

Myocardial thallium-201 (Tl-201) imaging performed in conjunction with exercise stress has enhanced the accuracy of detecting coronary artery disease among patients with chest pain. Sensitivity and specificity of qualitative visual Tl-201 scintigraphy for detection of coronary artery disease average 84% and 87%, respectively. Quantitative analysis of planar Tl-201 scintigrams has yielded sensitivity and specificity in the 90% range. Single photon emission computed tomographic imaging is associated with even higher sensitivity but with specificity in the 82-85% range. Perfusion defects representing ischemia can now be distinguished from scar by demonstration of delayed Tl-201 redistribution or enhanced uptake after reinjection of a second dose of Tl-201. Stenoses of the left circumflex coronary artery are less easily detected than lesions of the right and left anterior descending coronary arteries. False-positive Tl-201 perfusion defects may occur as a result of attenuation artifacts, most often caused by overlying breast tissue or by a high left hemidiaphragm. Patient motion during acquisition of single photon emission computed tomographic images results in artifactual defects on reconstruction. Abnormal Tl-201 uptake has been noted in patients with (1) left bundle branch block and normal coronary arteries, (2) hypertrophic cardiomyopathy, and (3) progressive systemic sclerosis.

Beller, G.A. (Department of Medicine, University of Virginia Health Sciences Center, Charlottesville (United States))

1991-09-01

388