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1

Inverted left atrial appendage in an infant during cardiac surgery.  

PubMed

Inverted left atrial appendage is an unusual complication associated with congenital cardiac surgery. Inversion of the left atrial appendage may occur during the surgical procedure or afterwards. The left atrial appendage may invert iatrogenically or as a result of the negative pressure during placement or removal of the left atrial vent or during deairing manoeuvres. This event can be life-threatening because of the mass effect of the atrial appendage within the left atrial cavity. PMID:24774963

Onan, Ismihan S; Haydin, Sertac; Yeniterzi, Mehmet

2015-03-01

2

Cardiac failure and left ventricular assist devices  

Microsoft Academic Search

Congestive heart failure (CHF) is a clinical syndrome defined as chronic, in- adequate myocardial contraction and relaxation that results in decreased cardiac output. It has multiple etiologies, including coronary artery disease causing is- chemic changes, valvular heart disease, viral cardiomyopathies, and congenital disease.Amajorcause of morbidityand mortality inthe United States,CHF affects more than 4 million people each year and causes approximately

Douglas J. Hirsch; John R. Cooper

3

Coronary anomaly with a left ventricular accessory chamber: Is it left ventricular aneurysm or diverticulum?  

PubMed Central

A 60-year-old male hypertensive was suspected to have post myocardial infarction left ventricular aneurysm. His transthoracic echocardiogram performed elsewhere reported an inferior wall left ventricular aneurysm. He was referred for coronary angiography. His coronary angiogram and repeat transthoracic echocardiogram demonstrated an accessory chamber arising from mid-inferior wall synchronously contracting with the left ventricle suggesting a diverticulum. In addition, he had anomalous coronary arteries with coronary artery disease. His electrocardiogram did not reveal any features suggestive of a post infarct aneurysm. This case illustrates the importance of a comprehensive clinical and echocardiographic examination with a broad differential thought process. PMID:23960694

Panduranga, Prashanth; Al-Riyami, Abdullah Amour

2012-01-01

4

Pulmonary Hypertension Related to Left-Sided Cardiac Pathology  

PubMed Central

Pulmonary hypertension (PH) is the end result of a variety of diverse pathologic processes. The chronic elevation in pulmonary artery pressure often leads to right ventricular pressure overload and subsequent right ventricular failure. In patients with left-sided cardiac disease, PH is quite common and associated with increased morbidity and mortality. This article will review the literature as it pertains to the epidemiology, pathogenesis, and diagnosis of PH related to aortic valve disease, mitral valve disease, left ventricular systolic and diastolic dysfunction, and pulmonary veno-occlusive disease. Moreover, therapeutic strategies, which focus on treating the underlying cardiac pathology will be discussed. PMID:21660234

Kiefer, Todd L.; Bashore, Thomas M.

2011-01-01

5

Infective Left Atrial Dissecting Flap after Cardiac Surgery  

PubMed Central

Left atrial dissection (LatD), defined as the forced separation of the left atrial (LA) wall layers by blood, is a rare and severe complication of cardiac surgery. It is most frequently associated with atrioventricular junction injuries. We report a case of infected LatD after coronary artery bypass graft, mitral valve replacement, aortic valve replacement and ascending aortic root replacement. The patient was presented with septicemia and disseminated intravascular coagulation. To the best of our knowledge, this is the first case report of LA dissecting flap concomitant with attached infective vegetations identified by transesophageal echocardiography. PMID:25309695

Tabiban, Sasan; Ghaemian, Ali; Bagheri, Babak; Shokri, Mojtaba

2014-01-01

6

Shape and dimensions of cardiac chambers: Importance of CT section thickness and orientation. [Dogs  

Microsoft Academic Search

Three-dimensional (3D) computed tomography (CT) scan data were used to quantitate the geometry of all heart chambers. The Dynamic Spatial Reconstructor (DSR) was used to scan dogs with in situ casts of the cardiac chambers. Chamber volumes estimated from DSR images were accurate within 5% of water displacement volume measurements of the actual casts for chambers greater than 11 ml

E. A. Hoffman; E. L. Ritman

1985-01-01

7

Thrombi in all four cardiac chambers in a patient with an old anteroseptal myocardial infarction and atrial flutter.  

PubMed

Cases with thrombi in multiple cardiac chambers are rare. We report an extremely rare case in which thrombi were formed in all four cardiac chambers at the same time. A 55-year-old man presented with biventricular failure and liver dysfunction. A 12-lead ECG and an echocardiogram revealed an old anteroseptal myocardial infarction with aneurysm formation and atrial flutter. A transesophageal echocardiogram and a CT of the chest revealed thrombi in the right and left atrial appendage, right ventricular apex and left ventricular aneurysm. Pulmonary emboli were also identified. Stasis of the blood due to ventricular dysfunction and atrial flutter was considered to be responsible. The patient died of multiorgan failure due to circulatory failure. PMID:25422354

Ida, Hanae; Hirata, Kazuhito; Takahashi, Takanori; Hirosawa, Takanobu

2014-01-01

8

Left ventricular dysfunction mimicking Takotsubo cardiomyopathy following cardiac surgery.  

PubMed

Left ventricular dysfunction with apical ballooning consistent with Takotsubo cardiomyopathy was encountered in a 68-year-old woman at 5 h after an uneventful mitral valve replacement and tricuspid valve repair. Preoperatively, the patient had emotional stress as well as worsening congestive heart failure, which might have contributed to this rare postoperative complication. Following diagnosis by transthoracic echocardiography (TTE), and characteristic findings of apical ballooning and a preserved basal contraction of the left ventricle, intra-aortic balloon pumping (IABP) was initiated to minimize the use of inotropic drugs. The patient was successfully weaned from both the IABP and pharmacological support. Follow up with serial TTE showed a gradual recovery of the left ventricle to normal systolic function. The mechanism of onset and pathophysiology of Takotsubo cardiomyopathy remain unclear, especially in postoperative cardiac surgery patients. Since excessive catecholamine stimulation has been proposed as a possible mechanism of Takotsubo cardiomyopathy, early mechanical circulatory assistance after cardiac surgery is advised to minimize catecholamine use in this rare complication. PMID:21863664

Yamane, Kentaro; Hirose, Hitoshi; Reeves, Gordon R; Marhefka, Gregary D; Silvestry, Scott C

2011-07-01

9

Semi-automatic algorithm for construction of the left ventricular area variation curve over a complete cardiac cycle  

PubMed Central

Background Two-dimensional echocardiography (2D-echo) allows the evaluation of cardiac structures and their movements. A wide range of clinical diagnoses are based on the performance of the left ventricle. The evaluation of myocardial function is typically performed by manual segmentation of the ventricular cavity in a series of dynamic images. This process is laborious and operator dependent. The automatic segmentation of the left ventricle in 4-chamber long-axis images during diastole is troublesome, because of the opening of the mitral valve. Methods This work presents a method for segmentation of the left ventricle in dynamic 2D-echo 4-chamber long-axis images over the complete cardiac cycle. The proposed algorithm is based on classic image processing techniques, including time-averaging and wavelet-based denoising, edge enhancement filtering, morphological operations, homotopy modification, and watershed segmentation. The proposed method is semi-automatic, requiring a single user intervention for identification of the position of the mitral valve in the first temporal frame of the video sequence. Image segmentation is performed on a set of dynamic 2D-echo images collected from an examination covering two consecutive cardiac cycles. Results The proposed method is demonstrated and evaluated on twelve healthy volunteers. The results are quantitatively evaluated using four different metrics, in a comparison with contours manually segmented by a specialist, and with four alternative methods from the literature. The method's intra- and inter-operator variabilities are also evaluated. Conclusions The proposed method allows the automatic construction of the area variation curve of the left ventricle corresponding to a complete cardiac cycle. This may potentially be used for the identification of several clinical parameters, including the area variation fraction. This parameter could potentially be used for evaluating the global systolic function of the left ventricle. PMID:20078864

2010-01-01

10

Morphological and Volumetric Analysis of Left Atrial Appendage and Left Atrium: Cardiac Computed Tomography-Based Reproducibility Assessment  

PubMed Central

Objectives Left atrial appendage (LAA) dilatation and morphology may influence an individual's risk for intracardiac thrombi and ischemic stroke. LAA size and morphology can be evaluated using cardiac computed tomography (cCT). The present study evaluated the reproducibility of LAA volume and morphology assessments. Methods A total of 149 patients (47 females; mean age 60.9±10.6 years) with suspected cardioembolic stroke/transient ischemic attack underwent cCT. Image quality was rated based on four categories. Ten patients were selected from each image quality category (N?=?40) for volumetric reproducibility analysis by two individual readers. LAA and left atrium (LA) volume were measured in both two-chamber (2CV) and transversal view (TV) orientation. Intertechnique reproducibility was assessed between 2CV and TV (200 measurement pairs). LAA morphology (A?=?Cactus, B?=?ChickenWing, C?=?WindSock, D?=?CauliFlower), LAA opening height, number of LAA lobes, trabeculation, and orientation of the LAA tip was analysed in all study subjects by three individual readers (447 interobserver measurement pairs). The reproducibility of volume measurements was assessed by intra-class correlation (ICC) and the reproducibility of LAA morphology assessments by Cohen's kappa. Results The intra-observer and interobserver reproducibility of LAA and LA volume measurements was excellent (ICCs>0.9). The LAA (ICC?=?0.954) and LA (ICC?=?0.945) volume measurements were comparable between 2CV and TV. Morphological classification (??=?0.24) and assessments of LAA opening height (??=?0.1), number of LAA lobes (??=?0.16), trabeculation (??=?0.15), and orientation of the LAA tip (??=?0.37) was only slightly to fairly reproducible. Conclusions LA and LAA volume measurements on cCT provide excellent reproducibility, whereas visual assessment of LAA morphological features is challenging and results in unsatisfactory agreement between readers. PMID:24988467

Taina, Mikko; Korhonen, Miika; Haataja, Mika; Muuronen, Antti; Arponen, Otso; Hedman, Marja; Jäkälä, Pekka; Sipola, Petri; Mustonen, Pirjo; Vanninen, Ritva

2014-01-01

11

[Results of randomized studies on cardiac resynchronization therapy and the reevaluation of cardiac ventricular activation in left bundle branch block].  

PubMed

If New York Heart Association Class II-IV heart failure is present, and ejection fraction ?35%, electrocardiographic QRS width ? 120 ms in the presence of left bundle branch block, cardiac resynchronization therapy is indicated. Reevaluation of the data of cardiac resynchronization trials and electrophysiologic findings in left bundle branch block provided evidence that "true" left bundle branch block requires a QRS width of ?130 ms (in woman) and ?140 ms (in man). In "true" left bundle branch block, after the 40th ms of the QRS notched/slurred R waves are characteristic in minimum two of I, aVL, V1, V2, V5 and V6 leads, in addition to a ?40 ms increase of the QRS complex, as compared to the original QRS complex. In contrast, slowly and continuously widened "left bundle branch block like" QRS patterns are mostly occur in left ventricular hypertrophy or in a metabolic/infiltrative disease. PMID:23628729

Préda, István

2013-05-01

12

Shape and dimensions of cardiac chambers: Importance of CT section thickness and orientation. [Dogs  

SciTech Connect

Three-dimensional (3D) computed tomography (CT) scan data were used to quantitate the geometry of all heart chambers. The Dynamic Spatial Reconstructor (DSR) was used to scan dogs with in situ casts of the cardiac chambers. Chamber volumes estimated from DSR images were accurate within 5% of water displacement volume measurements of the actual casts for chambers greater than 11 ml and within 10% of water displacement volumes for chambers less than 11 ml. Anatomic features of the actual cast correlated closely with anatomy visible in computer-generated surface images of the 3D DSR image data. The important effect of reconstructed section thickness and orientation on the fidelity of 3D cardiac geometry is demonstrated.

Hoffman, E.A.; Ritman, E.L.

1985-06-01

13

Cardiac magnetic resonance T1 mapping of left atrial myocardium  

PubMed Central

BACKGROUND Cardiac magnetic resonance (CMR) T1 mapping is an emerging tool for objective quantification of myocardial fibrosis. OBJECTIVES To (a) establish the feasibility of left atrial (LA) T1 measurements, (b) determine the range of LA T1 values in patients with atrial fibrillation (AF) vs healthy volunteers, and (c) validate T1 mapping vs LA intracardiac electrogram voltage amplitude measures. METHODS CMR imaging at 1.5 T was performed in 51 consecutive patients before AF ablation and in 16 healthy volunteers. T1 measurements were obtained from the posterior LA myocardium by using the modified Look-Locker inversion-recovery sequence. Given the established association of reduced electrogram amplitude with fibrosis, intracardiac point-by-point bipolar LA voltage measures were recorded for the validation of T1 measurements. RESULTS The median LA T1 relaxation time was shorter in patients with AF (387 [interquartile range 364–428] ms) compared to healthy volunteers (459 [interquartile range 418–532] ms; P < .001) and was shorter in patients with AF with prior ablation compared to patients without prior ablation (P = .035). In a generalized estimating equations model, adjusting for data clusters per participant, age, rhythm during CMR, prior ablation, AF type, hypertension, and diabetes, each 100-ms increase in T1 relaxation time was associated with 0.1 mV increase in intracardiac bipolar LA voltage (P = .025). CONCLUSIONS Measurement of the LA myocardium T1 relaxation time is feasible and strongly associated with invasive voltage measures. This methodology may improve the quantification of fibrotic changes in thin-walled myocardial tissues. PMID:23643513

Beinart, Roy; Khurram, Irfan M.; Liu, Songtao; Yarmohammadi, Hirad; Halperin, Henry R.; Bluemke, David A.; Gai, Neville; van der Geest, Rob J.; Lima, Joao A.C.; Calkins, Hugh; Zimmerman, Stefan L.; Nazarian, Saman

2013-01-01

14

Transcranial Doppler ultrasound identifies patients with right-to-left cardiac or pulmonary shunts.  

PubMed

We performed transcranial Doppler ultrasound (TCD) and transesophageal contrast echocardiography simultaneously in four patients. In one patient with a patent foramen ovale and another patient with pulmonary A-V fistulae, we detected micro air bubbles in the right middle cerebral artery three to five cardiac cycles after their appearance in the left atrium following intravenous injection of contrast. In two patients without right-to-left shunts, we did not detect air bubbles in the left atrium or middle cerebral artery following injection of contrast. These results show that TCD can identify patients with right-to-left cardiac or pulmonary shunts. PMID:1745345

Chimowitz, M I; Nemec, J J; Marwick, T H; Lorig, R J; Furlan, A J; Salcedo, E E

1991-12-01

15

Minimally invasive left ventricular assist device explantation after cardiac recovery: surgical technical considerations.  

PubMed

The new generation of left ventricular assist devices (LVADs) has enabled minimally invasive surgical procedures for implantation. Herein we present two alternative approaches for minimally invasive LVAD explantation following cardiac recovery, avoiding a sternotomy and improving patient safety. PMID:24571624

Schmitto, Jan D; Rojas, Sebastian V; Hanke, Jasmin S; Avsar, Murat; Haverich, Axel

2014-06-01

16

Scintigraphic Evaluation of Left Ventricular Function and Correlation with Autonomic Cardiac Neuropathy in Diabetic Patients  

Microsoft Academic Search

Left ventricular function of 20 diabetic patients was investigated at rest and during hand-grip test using radionuclide ventriculography. The aim of the study was to discuss the correlation of cardiac function with autonomic cardiac neuropathy (ACN) in diabetic subjects. ACN was tested using heart rate response to valsalva maneuver, standing up, deep breathing; blood pressure response to standing up, sustained

Tomris Erbas; Belkis Erbas; Okay Gedik; Sevinc Bïberoglu; Coskun F. Bekdik

1992-01-01

17

Cardiac Fabry's disease: an unusual cause of left ventricular hypertrophy  

Microsoft Academic Search

Background A 64-year-old male was observed as an outpatient with atypical, non-exercise-induced chest pain and palpitations. He had arterial hypertension and marked concentric left ventricular hypertrophy. After 2.5 years of antihypertensive drug therapy the patient's blood pressure had returned to normal, but his left ventricular hypertrophy was unchanged.Investigations Electrocardiography, transthoracic echocardiography, myocardial perfusion scintigraphic imaging, measurement of ?-galactosidase A activity,

Ovídio Costa; Maria do Sameiro Faria; Pedro Bernardo Almeida; Lúcia Lacerda; José Pedro L Nunes

2007-01-01

18

Ghost in the left ventricle on electrocardiogram-gated cardiac computed tomography by turbulent flow.  

PubMed

We report on an extremely rare case of a fake lesion in the left ventricle on electrocardiogram-gated cardiac computed tomography simulating thrombus or tumor by turbulent flow in a 14-year-old boy. Cardiac magnetic resonance imaging with contrast-enhanced myocardial perfusion and delayed enhancement images were helpful in excluding true thrombus or tumor. Awareness of this potential pitfall is critical in order to avoid unnecessary anticoagulation or surgery. PMID:25229204

Byun, Sung Su; Sung, Yon Mi; Lee, Kyounghoon; Kim, Yoon Kyung; Park, Jae Hyung

2015-01-01

19

Capsule endoscopy in patients with cardiac pacemakers, implantable cardioverter defibrillators and left heart assist devices  

PubMed Central

According to the recommendations of the US Food and Drug Administration and manufacturers, capsule endoscopy should not be used in patients carrying implanted cardiac devices. For this review we considered studies indexed (until 30.06.2013) in Medline [keywords: capsule endoscopy, small bowel endoscopy, cardiac pacemaker, implantable cardioverter defibrillator, interference, left heart assist device], technical information from Given Imaging and one own publication (not listed in Medline). Several in vitro and in vivo studies included patients with implanted cardiac devices who underwent capsule endoscopy. No clinically relevant interference was noticed. Initial reports on interference with a simulating device were not reproduced. Furthermore technical data of PillCam (Given Imaging) demonstrate that the maximum transmission power is below the permitted limits for cardiac devices. Hence, impairment of cardiac pacemaker, defibrillator or left ventricular heart assist device function by capsule endoscopy is not expected. However, wireless telemetry can cause dysfunction of capsule endoscopy recording. Application of capsule endoscopy is feasible and safe in patients with implanted cardiac devices such as pacemakers, cardioverter defibrillators, and left heart assist devices. Development of new technologies warrants future re-evaluation. PMID:24714370

Bandorski, Dirk; Höltgen, Reinhard; Stunder, Dominik; Keuchel, Martin

2014-01-01

20

Left ventricular assist devices as a bridge to cardiac transplantation  

PubMed Central

Heart failure remains a significant cause of morbidity and mortality, affecting over five million patients in the United States. Continuous-flow left ventricular assist devices (LVAD) have become the standard of care for patients with end stage heart failure. This review highlights the current state of LVAD as a bridge to transplant (BTT) in patients requiring mechanical circulatory support (MCS). PMID:25132978

Holley, Christopher T.; Harvey, Laura

2014-01-01

21

Cardiac memory during rather than after termination of left bundle branch block.  

PubMed

An 83-year-old woman with chronic left bundle branch block and remote history of pacemaker implantation for intermittent AV block was hospitalized for fatigue and leg swelling. She had no cardiac complaints. Routine 12-lead electrocardiogram showed sinus rhythm with left bundle branch block. There were diffuse negative T waves in the inferior and anterolateral leads that were concordant with the QRS complexes. Echocardiogram was normal and nuclear perfusion heart scan showed no abnormality. It was noted that the negative T waves during left bundle branch block were in the exact same leads as were the deep negative QRS complexes during ventricular pacing. The electrocardiographic changes were consistent with cardiac memory. This case is unique because cardiac memory in patients with intermittent left bundle branch block typically occurs when the QRS complexes normalize and not during left bundle branch block itself. Our findings indicate that memory Ts can develop not only after normalization of wide complex rhythms but also with alternating wide complex rhythms as in the presented case where a ventricular paced rhythm was replaced by left bundle branch block. PMID:25172185

Littmann, Laszlo; Proctor, Patrick A; Givens, Priscilla M

2014-01-01

22

Automatic functional analysis of left ventricle in cardiac cine MRI  

PubMed Central

Rationale and objectives A fully automated left ventricle segmentation method for the functional analysis of cine short axis (SAX) magnetic resonance (MR) images was developed, and its performance evaluated with 133 studies of subjects with diverse pathology: ischemic heart failure (n=34), non-ischemic heart failure (n=30), hypertrophy (n=32), and healthy (n=37). Materials and methods The proposed automatic method locates the left ventricle (LV), then for each image detects the contours of the endocardium, epicardium, papillary muscles and trabeculations. Manually and automatically determined contours and functional parameters were compared quantitatively. Results There was no significant difference between automatically and manually determined end systolic volume (ESV), end diastolic volume (EDV), ejection fraction (EF) and left ventricular mass (LVM) for each of the four groups (paired sample t-test, ?=0.05). The automatically determined functional parameters showed high correlations with those derived from manual contours, and the Bland-Altman analysis biases were small (1.51 mL, 1.69 mL, –0.02%, –0.66 g for ESV, EDV, EF and LVM, respectively). Conclusions The proposed technique automatically and rapidly detects endocardial, epicardial, papillary muscles’ and trabeculations’ contours providing accurate and reproducible quantitative MRI parameters, including LV mass and EF. PMID:24040616

Lu, Ying-Li; Connelly, Kim A.; Dick, Alexander J.; Wright, Graham A.

2013-01-01

23

Real-time cardiac output estimation of the circulatory system under left ventricular assistance  

Microsoft Academic Search

A method for indirect and real-time estimation of the cardiac output of the circulatory system supported by the left ventricular assist device (LVAD) is proposed. This method has low invasiveness and is useful for clinical applications of the LVAD since it needs only two measurements: the rate of blood outflow from the LVAD and the aortic pressure. The method is

Makoto Yoshizawa; Hiroshi Takeda; Makoto Miura; Tomoyuki Yambe; Yoshiaki Katahira; Shin-ichi Nitta

1993-01-01

24

Post-hypothermic cardiac left ventricular systolic dysfunction after rewarming in an intact pig model  

PubMed Central

Introduction We developed a minimally invasive, closed chest pig model with the main aim to describe hemodynamic function during surface cooling, steady state severe hypothermia (one hour at 25°C) and surface rewarming. Methods Twelve anesthetized juvenile pigs were acutely catheterized for measurement of left ventricular (LV) pressure-volume loops (conductance catheter), cardiac output (Swan-Ganz), and for vena cava inferior occlusion. Eight animals were surface cooled to 25°C, while four animals were kept as normothermic time-matched controls. Results During progressive cooling and steady state severe hypothermia (25°C) cardiac output (CO), stroke volume (SV), mean arterial pressure (MAP), maximal deceleration of pressure in the cardiac cycle (dP/dtmin), indexes of LV contractility (preload recruitable stroke work, PRSW, and maximal acceleration of pressure in the cardiac cycle, dP/dtmax) and LV end diastolic and systolic volumes (EDV and ESV) were significantly reduced. Systemic vascular resistance (SVR), isovolumetric relaxation time (Tau), and oxygen content in arterial and mixed venous blood increased significantly. LV end diastolic pressure (EDP) remained constant. After rewarming all the above mentioned hemodynamic variables that were depressed during 25°C remained reduced, except for CO that returned to pre-hypothermic values due to an increase in heart rate. Likewise, SVR and EDP were significantly reduced after rewarming, while Tau, EDV, ESV and blood oxygen content normalized. Serum levels of cardiac troponin T (TnT) and tumor necrosis factor-alpha (TNF-?) were significantly increased. Conclusions Progressive cooling to 25°C followed by rewarming resulted in a reduced systolic, but not diastolic left ventricular function. The post-hypothermic increase in heart rate and the reduced systemic vascular resistance are interpreted as adaptive measures by the organism to compensate for a hypothermia-induced mild left ventricular cardiac failure. A post-hypothermic increase in TnT indicates that hypothermia/rewarming may cause degradation of cardiac tissue. There were no signs of inadequate global oxygenation throughout the experiments. PMID:21092272

2010-01-01

25

Case of persistent left superior vena cava draining via the left atrium with a normal coronary sinus utilizing cardiac CT.  

PubMed

With an estimated incidence of ? 0.5%-2% of the population and 10% of patients with congenital heart disorders, persistent LSVC is the most common venous anomaly of the chest. Most drain via the right atrium. Rarely (7.5% of cases), the persistent LSVC may drain directly into the left atrium. These are typically seen with a coronary sinus type atrial septal defect with many investigators believing that, embryologically, a normal coronary sinus cannot exist in the setting of a persistent LSVC draining into the left atrium. There have been few case reports of this in the setting of a normal coronary sinus. With the assistance of cardiac CT, we were able to show the existence of this rare entity. The CT images provided guidance for a successful endovascular repair. PMID:22732204

Middlebrooks, Erik; Wymer, David; Chandran, Arun

2012-01-01

26

Cardiac phase-targeted dynamic load on left ventricle differentially regulates phase-sensitive gene expressions and pathway activation.  

PubMed

The heart has remarkable capacity to adapt to mechanical load and to dramatically change its phenotype. The mechanism underlying such diverse phenotypic adaptations remains unknown. Since systolic overload induces wall thickening, while diastolic overload induces chamber enlargement, we hypothesized that cardiac phase-sensitive mechanisms govern the adaptation. We inserted a balloon into the left ventricle (LV) of a Langendorff perfused rat heart, and controlled LV volume (LVV) using a high performance servo-pump. We created isolated phasic systolic overload (SO) by isovolumic contraction (peak LV pressure >170mmHg) at unstressed diastolic LVV [end-diastolic pressure (EDP)=0mmHg]. We also created pure phasic diastolic overload (DO) by increasing diastolic LVV until EDP >40mmHg and unloading completely in systole. After 3hours under each condition, the myocardium was analyzed using DNA microarray. Gene expressions under SO and DO conditions were compared against unloaded control condition using gene ontology and pathway analysis (n=4 each). SO upregulated proliferation-related genes, whereas DO upregulated fibrosis-related genes (P<10(-5)). Both SO and DO upregulated genes related functionally to cardiac hypertrophy, although the gene profiles were totally different. Upstream regulators confirmed by Western blot indicated that SO activated extracellular signal-regulated kinase 1/2, c-Jun NH2-terminal kinase, and Ca(2+)/calmodulin-dependent protein kinase II (3.2-, 2.0-, and 4.7-fold versus control, P<0.05, n=5), whereas DO activated p38 (2.9-fold, P<0.01), which was consistent with the downstream gene expressions. In conclusion, pure isolated systolic and diastolic overload permits elucidation of cardiac phase-sensitive gene regulation. The genomic responses indicate that mechanisms governing the cardiac phase-sensitive adaptations are different. PMID:24004468

Onitsuka, Ken; Ide, Tomomi; Arai, Shinobu; Hata, Yuko; Murayama, Yoshinori; Hosokawa, Kazuya; Sakamoto, Takafumi; Tobushi, Tomoyuki; Sakamoto, Kazuo; Fujino, Takeo; Sunagawa, Kenji

2013-11-01

27

Computer-aided scheme for functional index computation of left ventricle in cardiac CTA: segmentation and partitioning of left ventricle  

NASA Astrophysics Data System (ADS)

Cardiac functional indices, such as ejection fraction and regional wall motion/ thickening, are commonly used for assessing the contractility and functionality of the heart in clinical practice. An important step for computer-aided determination of functional indices is the automated segmentation of the heart from computed tomography angiography (CTA) and the partitioning of the left ventricle into 16 segments. We develop a fully automatic scheme which not only segments the whole heart from cardiac CTA images, but also partitions the left ventricle, including the blood pool and myocardium, into 16 segments of bull's eye plot. The segmentation is based on image registration and atlas propagation techniques, whereas the bull's eye plot is first obtained through atlas propagation and then further improved to correct inconsistency across different subjects, uneven size for each segment and "zig-zag" edges between them. In this preliminary study, a cohort of ten clinical CTA data was employed to compute and evaluate the regional functional indices as well as the global indices.

Huang, Hui; Zhuang, Xiahai; Shao, Yi; Lan, Tian; Liu, Liu; Li, Qiang

2013-02-01

28

Physiologic analysis of cardiac cycle in an implantable impeller centrifugal left ventricular assist device.  

PubMed

The purpose of this study was to determine the physiologic relationship between the cardiac cycle and the nonpulsatile impeller centrifugal Taita No.1 left ventricular assist device (T-LVAD) in a chronic animal study. The relationship of the cardiac cycle, pump flow, aortic pressure, left ventricle pressure, and pump power were analyzed by 5 phases in 4 stages. The isovolumetric ventricular phase is from mitral valve closure (MVC) to aortic valve opening (AVO) and is called Stage 1. The ejection phase is from AVO to aortic valve closure (AVC) and is called Stage 2. The isovolumetric relaxation phase is from AVC to MVC and is called Stage 3. The passive filling and atrial contraction phase is from MVC to mitral valve opening (MVO) and called Stage 4. Based on evidence from the physiologic volume change of the left ventricle, the change of pump flow of the T-LVAD in a cardiac cycle by variable voltages of pump control was evaluated using animal models. After left posteriolateral thoracotomy via the fifth intercostal space under general anesthesia, the nonpulsatile centrifugal T-LVAD was implanted into 2 healthy calves. The inflow of the T-LVAD was inserted into the left ventricle through the mitral valve via the left atrial appendage. The arterial blood pressure waveform was measured and recorded on the outflow of the T-LVAD. The 4 phases of a cardiac cycle were defined as MVC-AVO (Stage 1), AVO-AVC (Stage 2), AVC-MVO (Stage 3) and MVC-MVO (Stage 4) according to the outflow pressure of the outflow of the T-LVAD and differential pressure between the outflow and inflow of the T-LVAD. We carried out the real-time waveform measurement for electrocardiogram, the outflow pressure, the T-LVAD flow and the speed, as well as open loop and constant voltage (V). In a cardiac cycle, the sensing current of the T-LVAD was inverse to the speed. The flow of the T-LVAD at the 4 stages was measured individually and analyzed with different control voltages from 10 to 18 V. The highest flow ratio of MVC-AVC/AVC-MVC was noted when the T-LVAD worked on 14 V. By using analysis methodology of the flow ratio of a cardiac cycle, the optimal physiologically effective control of the T-LVAD might be achieved. PMID:11531711

Chou, N K; Wang, S S; Chu, S H; Chen, Y S; Lin, Y H; Chang, C J; Shyu, J J; Jan, G J

2001-08-01

29

Prognostic value of left ventricular diastolic dysfunction in patients undergoing cardiac catheterization for coronary artery disease.  

PubMed

We hypothesized that left ventricular (LV) diastolic dysfunction assessed by cardiac catheterization may be associated with increased risk for cardiovascular events. To test the hypothesis, we assessed diastolic function by cardiac catheterization (relaxation time constant (Tau) and end-diastolic pressure (EDP)) as well as Doppler echocardiography (early diastolic mitral annular velocity (e') and a ratio of early diastolic mitral inflow to annular velocities (E/e')) in 222 consecutive patients undergoing cardiac catheterization for coronary artery disease (CAD). During a followup of 1364 ± 628 days, 5 cardiac deaths and 20 unscheduled cardiovascular hospitalizations were observed. Among LV diastolic function indices, Tau > 48?ms and e' < 5.8?cm/s were each significantly associated with lower rate of survival free of cardiovascular hospitalization. Even after adjustment for potential confounders (traditional cardiovascular risk factors, the severity of CAD, and cardiovascular medications), the predictive value of Tau > 48?ms and e' < 5.8?cm/s remained significant. No predictive value was observed in EDP, E/e', or LV ejection fraction. In conclusion, LV diastolic dysfunction, particularly impaired LV relaxation assessed by both cardiac catheterization and Doppler echocardiography, is independently associated with increased risk for cardiac death or cardiovascular hospitalization in patients with known or suspected CAD. PMID:22567531

Fukuta, Hidekatsu; Ohte, Nobuyuki; Wakami, Kazuaki; Goto, Toshihiko; Tani, Tomomitsu; Kimura, Genjiro

2012-01-01

30

Fetal-Adult Cardiac Transcriptome Analysis in Rats with Contrasting Left Ventricular Mass Reveals New Candidates for Cardiac Hypertrophy  

PubMed Central

Reactivation of fetal gene expression patterns has been implicated in common cardiac diseases in adult life including left ventricular (LV) hypertrophy (LVH) in arterial hypertension. Thus, increased wall stress and neurohumoral activation are discussed to induce the return to expression of fetal genes after birth in LVH. We therefore aimed to identify novel potential candidates for LVH by analyzing fetal-adult cardiac gene expression in a genetic rat model of hypertension, i.e. the stroke-prone spontaneously hypertensive rat (SHRSP). To this end we performed genome-wide transcriptome analysis in SHRSP to identify differences in expression patterns between day 20 of fetal development (E20) and adult animals in week 14 in comparison to a normotensive rat strain with contrasting low LV mass, i.e. Fischer (F344). 15232 probes were detected as expressed in LV tissue obtained from rats at E20 and week 14 (p < 0.05) and subsequently screened for differential expression. We identified 24 genes with SHRSP specific up-regulation and 21 genes with down-regulation as compared to F344. Further bioinformatic analysis presented Efcab6 as a new candidate for LVH that showed only in the hypertensive SHRSP rat differential expression during development (logFC = 2.41, p < 0.001) and was significantly higher expressed in adult SHRSP rats compared with adult F344 (+ 76%) and adult normotensive Wistar-Kyoto rats (+ 82%). Thus, it represents an interesting new target for further functional analyses and the elucidation of mechanisms leading to LVH. Here we report a new approach to identify candidate genes for cardiac hypertrophy by combining the analysis of gene expression differences between strains with a contrasting cardiac phenotype with a comparison of fetal-adult cardiac expression patterns. PMID:25646840

Grabowski, Katja; Riemenschneider, Mona; Schulte, Leonard; Witten, Anika; Schulz, Angela; Stoll, Monika; Kreutz, Reinhold

2015-01-01

31

Hemolytic staining of the endocardium of the left heart chambers: a new sign for autopsy diagnosis of freshwater drowning.  

PubMed

Despite the availability of modern imaging and molecular tools, traditional autopsy, and laboratory findings remain the gold standard for the diagnosis of drowning. This article presents two cases of freshwater drowning in which hemolytic staining of the endocardium of the left heart chambers was observed at autopsy. One case was a suicidal drowning of an 84-year-old man, and the other case was an accidental drowning of an 86-year-old woman. In both cases, there was marked hemolytic staining of the endocardium of the left atrium and ventricle. The endocardium of the right heart chambers was clear and transparent in appearance. Hemolytic intimal staining of the aortic root was observed in one case. Gettler's test was positive in both cases. Hemolytic discoloration of the endocardium of the left heart chambers after freshwater drowning is analogous to hemolytic staining of the aortic root. Both staining patterns result from the hypo-osmolar hemolysis that occurs in the left heart chambers and systemic circulation after hypotonic fluid passes across the alveolocapillary membrane. Hemolytic discoloration of the endocardium of the left heart chambers at autopsy may support a diagnosis of freshwater drowning. PMID:25326681

Zátopková, Lenka; Hejna, Petr; Janík, Martin

2015-03-01

32

Transient cardiac arrest in patient with left ventricular noncompaction (spongiform cardiomyopathy).  

PubMed

Left ventricular noncompaction (LVNC), also known as spongiform cardiomyopathy, is a severe disease that has not previously been discussed with respect to general anesthesia. We treated a child with LVNC who experienced cardiac arrest. Dental treatment under general anesthesia was scheduled because the patient had a risk of endocarditis due to dental caries along with a history of being uncooperative for dental care. During sevoflurane induction, severe hypotension and laryngospasm resulted in cardiac arrest. Basic life support (cardiopulmonary resuscitation) was initiated to resuscitate the child, and his cardiorespiratory condition improved. Thereafter, an opioid-based anesthetic was performed, and recovery was smooth. In LVNC, opioid-based anesthesia is suggested to avoid the significant cardiac suppression seen with a volatile anesthetic, once intravenous access is established. Additionally, all operating room staff should master Advanced Cardiac Life Support/Pediatric Advanced Life Support (including intraosseous access), and more than 1 anesthesiologist should be present to induce general anesthesia, if possible, for this high-risk patient. PMID:21410361

Yamazaki, Shinya; Ito, Hiroshi; Kawaai, Hiroyoshi

2011-01-01

33

Catheter-induced left main coronary artery dissection resulting in abrupt closure and cardiac arrest: successful stenting during resuscitation.  

PubMed

Catheter-induced left main coronary artery dissection is an uncommon but devastating complication of coronary angiography and percutaneous coronary intervention. We present a case of left main coronary artery dissection induced with a guide catheter, which resulted in acute occlusion and cardiac arrest. Survival and complete functional recovery were achieved with bailout stenting. PMID:17404412

Ozdol, Cagdas; Oral, Dervis; Tutar, Eralp

2007-04-01

34

Cardiac resynchronization therapy for heart failure induced by left bundle branch block after transcatheter closure of ventricular septal defect  

PubMed Central

A 54-year-old female patient with congenital heart disease had a persistent complete left bundle branch block three months after closure by an Amplatzer ventricular septal defect occluder. Nine months later, the patient suffered from chest distress, palpitation, and sweating at daily activities, and her 6-min walk distance decreased significantly (155 m). Her echocardiography showed increased left ventricular end-diastolic diameter with left ventricular ejection fraction of 37%. Her symptoms reduced significantly one week after received cardiac resynchronization therapy. She had no symptoms at daily activities, and her echo showed left ventricular ejection fraction of 46% and 53%. Moreover, left ventricular end-diastolic diameter decreased 6 and 10 months after cardiac resynchronization therapy, and 6-min walk distance remarkably increased. This case demonstrated that persistent complete left bundle branch block for nine months after transcatheter closure with ventricular septal defect Amplatzer occluder could lead to left ventricular enlargement and a significant decrease in left ventricular systolic function. Cardiac resynchronization therapy decreased left ventricular end-diastolic diameter and increased left ventricular ejection fraction, thereby improving the patient's heart functions. PMID:25593586

Du, Rong-Zeng; Qian, Jun; Wu, Jun; Liang, Yi; Chen, Guang-Hua; Sun, Tao; Zhou, Ye; Zhao, Yang; Yan, Jin-Chuan

2014-01-01

35

A Collaborative Resource to Build Consensus for Automated Left Ventricular Segmentation of Cardiac MR Images  

PubMed Central

A collaborative framework was initiated to establish a community resource of ground truth segmentations from cardiac MRI. Multi-site, multi-vendor cardiac MRI datasets comprising 95 patients (73 men, 22 women; mean age 62.73 ± 11.24 years) with coronary artery disease and prior myocardial infarction, were randomly selected from data made available by the Cardiac Atlas Project (Fonseca et al., 2011). Three semi- and two fully-automated raters segmented the left ventricular myocardium from short-axis cardiac MR images as part of a challenge introduced at the STACOM 2011 MICCAI workshop (Suinesiaputra et al., 2012). Consensus myocardium images were generated based on the Expectation-Maximization principle implemented by the STAPLE algorithm (Warfield et al., 2004). The mean sensitivity, specificity, positive predictive and negative predictive values ranged between 0.63-0.85, 0.60-0.98, 0.56-0.94 and 0.83-0.92, respectively, against the STAPLE consensus. Spatial and temporal agreement varied in different amounts for each rater. STAPLE produced high quality consensus images if the region of interest was limited to the area of discrepancy between raters. To maintain the quality of the consensus, an objective measure based on the candidate automated rater performance distribution is proposed. The consensus segmentation based on a combination of manual and automated raters were more consistent than any particular rater, even those with manual input. The consensus is expected to improve with the addition of new automated contributions. This resource is open for future contributions, and is available as a test bed for the evaluation of new segmentation algorithms, through the Cardiac Atlas Project (www.cardiacatlas.org). PMID:24091241

Suinesiaputra, Avan; Cowan, Brett R.; Al-Agamy, Ahmed O.; AlAttar, Mustafa A.; Ayache, Nicholas; Fahmy, Ahmed S.; Khalifa, Ayman M.; Medrano-Gracia, Pau; Jolly, Marie-Pierre; Kadish, Alan H.; Lee, Daniel C.; Margeta, Ján; Warfield, Simon K.; Young, Alistair A.

2013-01-01

36

Effects of cardiac resynchronization therapy on left ventricular remodeling and dyssynchrony in patients with left ventricular noncompaction and heart failure.  

PubMed

Left ventricular noncompaction (LVNC) is a rare cardiomyopathy with high incidence of heart failure (HF). It is unclear whether LVNC patients with desynchronized HF would benefit from cardiac resynchronization therapy (CRT). In order to evaluate the effect of CRT on LVNC, this study explored left ventricular (LV) remodeling and mechanical synchronicity before and after CRT in LVNC patients, and compare with that in idiopathic dilated cardiomyopathy (DCM) patients. We collected 15 LVNC and 30 matched DCM patients. All the patients underwent clinical evaluation,electrocardiogram and echocardiography before CRT and ?6 months later. LV response was defined as ?15 % decrease in LV end-systolic volume (LVESV). Longitudinal synchronicity was quantified by YU-index using tissue Doppler imaging. The time delay of peak radial strain from anteroseptal to posterior wall, which derived from speckle tracking imaging, was used to quantify radial synchronicity. In LVNC group, LV ejection fraction increased from 27.6 ± 5.5 to 39.1 ± 7.0 % (P < 0.01) during follow-up, but LV volumes did not change significantly (both P > 0.05). Five LVNC patients (33.3 %) responded to CRT, and all of them were super-responders (reduction in LVESV > 30 %). In addition, the number of noncompacted segments and the thickness ratio of noncompacted to compacted myocardium decreased (both P < 0.05). Inter-ventricular, longitudinal and radial intra-ventricular dyssynchrony also reduced significantly (all P < 0.05). Compared with DCM group, there was no significant difference in LV response rate (33.3 vs. 60.0 %, P = 0.092), improvement of LV function and dyssynchrony index (all P < 0.05). In conclusion, CRT improved heart function, morphology and mechanical dyssynchrony in LVNC patients. PMID:25392055

Qiu, Qiong; Chen, Yang-Xin; Mai, Jing-Ting; Yuan, Wo-Liang; Wei, Yu-Lin; Liu, Ying-Mei; Yang, Li; Wang, Jing-Feng

2014-11-13

37

Cardiac gated ventilation  

NASA Astrophysics Data System (ADS)

There are several theoretic advantages to synchronizing positive pressure breaths with the cardiac cycle, including the potential for improving distribution of pulmonary and myocardial blood flow and enhancing cardiac output. We evaluated the effects of synchronizing respiration to the cardiac cycle using a programmable ventilator and electron beam CT (EBCT) scanning. The hearts of anesthetized dogs were imaged during cardiac gated respiration with a 50msec scan aperture. Multislice, short axis, dynamic image data sets spanning the apex to base of the left ventricle were evaluated to determine the volume of the left ventricular chamber at end-diastole and end-systole during apnea, systolic and diastolic cardiac gating. We observed an increase in cardiac output of up to 30% with inspiration gated to the systolic phase of the cardiac cycle in a nonfailing model of the heart.

Hanson, C. William, III; Hoffman, Eric A.

1995-05-01

38

Cardiac gated ventilation  

SciTech Connect

There are several theoretic advantages to synchronizing positive pressure breaths with the cardiac cycle, including the potential for improving distribution of pulmonary and myocardial blood flow and enhancing cardiac output. The authors evaluated the effects of synchronizing respiration to the cardiac cycle using a programmable ventilator and electron beam CT (EBCT) scanning. The hearts of anesthetized dogs were imaged during cardiac gated respiration with a 50 msec scan aperture. Multi slice, short axis, dynamic image data sets spanning the apex to base of the left ventricle were evaluated to determine the volume of the left ventricular chamber at end-diastole and end-systole during apnea, systolic and diastolic cardiac gating. The authors observed an increase in cardiac output of up to 30% with inspiration gated to the systolic phase of the cardiac cycle in a non-failing model of the heart.

Hanson, C.W. III [Hospital of the Univ. of Pennsylvania, Philadelphia, PA (United States). Dept. Anesthesia; Hoffman, E.A. [Univ. of Iowa College of Medicine, Iowa City, IA (United States). Div. of Physiologic Imaging

1995-12-31

39

Berberine attenuates adverse left ventricular remodeling and cardiac dysfunction after acute myocardial infarction in rats: role of autophagy.  

PubMed

The present study aimed to test the hypothesis that berberine, a plant-derived anti-oxidant, attenuates adverse left ventricular remodelling and improves cardiac function in a rat model of myocardial infarction (MI). Furthermore, the potential mechanisms that mediated the cardioprotective actions of berberine, in particular the effect on autophagy, were also investigated. Acute MI was induced by ligating the left anterior descending coronary artery of Sprague-Dawley rats. Cardiac function was assessed by transthoracic echocardiography. The protein activity/levels of autophagy related to signalling pathways (e.g. LC-3B, Beclin-1) were measured in myocardial tissue by immunohistochemical staining and western blot. Four weeks after MI, berberine significantly prevented cardiac dysfunction and adverse cardiac remodelling. MI rats treated with low dose berberine (10 mg/kg per day) showed higher left ventricular ejection fraction and fractional shortening than those treated with high-dose berberine (50 mg/kg per day). Both doses reduced interstitial fibrosis and post-MI adverse cardiac remodelling. The cardioprotective action of berberine was associated with increased LC-3B II and Beclin-1 expressions. Furthermore, cardioprotection with berberine was potentially related to p38 MAPK inhibition and phospho-Akt activation. The present in vivo study showed that berberine is effective in promoting autophagy, and subsequently attenuating left ventricular remodelling and cardiac dysfunction after MI. The potential underlying mechanism is augmentation of autophagy through inhibition of p38 MAPK and activation of phospho-Akt signalling pathways. PMID:25224725

Zhang, Yao-Jun; Yang, Shao-Hua; Li, Ming-Hui; Iqbal, Javaid; Bourantas, Christos V; Mi, Qiong-Yu; Yu, Yi-Hui; Li, Jing-Jing; Zhao, Shu-Li; Tian, Nai-Liang; Chen, Shao-Liang

2014-12-01

40

Cardiac protein changes in ischaemic and dilated cardiomyopathy: a proteomic study of human left ventricular tissue.  

PubMed

The development of heart failure (HF) is characterized by progressive alteration of left ventricle structure and function. Previous works on proteomic analysis in cardiac tissue from patients with HF remain scant. The purpose of our study was to use a proteomic approach to investigate variations in protein expression of left ventricle tissue from patients with ischaemic (ICM) and dilated cardiomyopathy (DCM). Twenty-four explanted human hearts, 12 from patients with ICM and 12 with DCM undergoing cardiac transplantation and six non-diseased donor hearts (CNT) were analysed by 2DE. Proteins of interest were identified by mass spectrometry and validated by Western blotting and immunofluorescence. We encountered 35 differentially regulated spots in the comparison CNT versus ICM, 33 in CNT versus DCM, and 34 in ICM versus DCM. We identified glyceraldehyde 3-phophate dehydrogenase up-regulation in both ICM and DCM, and alpha-crystallin B down-regulation in both ICM and DCM. Heat shock 70 protein 1 was up-regulated only in ICM. Ten of the eleven differentially regulated proteins common to both aetiologies are interconnected as a part of a same network. In summary, we have shown by proteomics analysis that HF is associated with changes in proteins involved in the cellular stress response, respiratory chain and cardiac metabolism. Although we found altered expression of eleven proteins common to both ischaemic and dilated aetiology, we also observed different proteins altered in both groups. Furthermore, we obtained that seven of these eleven proteins are involved in cell death and apoptosis processes, and therefore in HF progression. PMID:22435364

Roselló-Lletí, Esther; Alonso, Jana; Cortés, Raquel; Almenar, Luis; Martínez-Dolz, Luis; Sánchez-Lázaro, Ignacio; Lago, Francisca; Azorín, Inmaculada; Juanatey, Jose R González; Portolés, Manuel; Rivera, Miguel

2012-10-01

41

Tomotherapy and Multifield Intensity-Modulated Radiotherapy Planning Reduce Cardiac Doses in Left-Sided Breast Cancer Patients With Unfavorable Cardiac Anatomy  

SciTech Connect

Purpose: For patients with left-sided breast cancers, radiation treatment to the intact breast results in high doses to significant volumes of the heart, increasing the risk of cardiac morbidity, particularly in women with unfavorable cardiac anatomy. We compare helical tomotherapy (TOMO) and inverse planned intensity modulated radiation therapy (IMRT) with three-dimensional conformal radiotherapy using opposed tangents (3D-CRT) for reductions in cardiac volumes receiving high doses. Methods and Materials: Fifteen patients with left-sided breast cancers and unfavorable cardiac anatomy, determined by a maximum heart depth (MHD) of {>=}1.0 cm within the tangent fields, were planned for TOMO and IMRT with five to seven beam angles, in addition to 3D-CRT. The volumes of heart and left ventricle receiving {>=}35 Gy (V35) were compared for the plans, as were the mean doses to the contralateral breast and the volume receiving {>=}20 Gy (V20) for the ipsilateral lung. Results: The mean MHD was 1.7 cm, and a significant correlation was observed between MHD and both heart and left ventricle V35. The V35s for IMRT (0.7%) and TOMO (0.5%) were significantly lower than for 3D-CRT (3.6%). The V20 for IMRT (22%) was significantly higher than for 3D-CRT (15%) or TOMO (18%), but the contralateral breast mean dose for TOMO (2.48 Gy) was significantly higher than for 3D-CRT (0.93 Gy) or IMRT (1.38 Gy). Conclusions: Both TOMO and IMRT can significantly reduce cardiac doses, with modest increases in dose to other tissues in left-sided breast cancer patients with unfavorable cardiac anatomy.

Coon, Alan B., E-mail: Alan_Coon@rush.ed [Department of Radiation Oncology, Rush University Medical Center, Chicago, IL (United States); Dickler, Adam [Department of Radiation Oncology, Little Company of Mary Hospital, Evergreen Park, IL (United States); Kirk, Michael C. [Massachusetts General/North Shore Cancer Center, Danvers, MA (United States); Liao Yixiang; Shah, Anand P.; Strauss, Jonathan B.; Chen, Sea; Turian, Julius; Griem, Katherine L. [Department of Radiation Oncology, Rush University Medical Center, Chicago, IL (United States)

2010-09-01

42

Quantitative assessment of left ventricular function with dual-source CT in comparison to cardiac magnetic resonance imaging: initial findings  

Microsoft Academic Search

Cardiac magnetic resonance imaging and echocardiography are currently regarded as standard modalities for the quantification\\u000a of left ventricular volumes and ejection fraction. With the recent introduction of dual-source computedtomography (DSCT),\\u000a the increased temporal resolution of 83 ms should also improve the assessment of cardiac function in CT. The aim of this study\\u000a was to evaluate the accuracy of DSCT in the

S. Busch; T. R. C. Johnson; B. J. Wintersperger; N. Minaifar; A. Bhargava; C. Rist; M. F. Reiser; C. Becker; K. Nikolaou

2008-01-01

43

A VALENTINE-SHAPED CARDIAC SILHOUETTE IN FELINE THORACIC RADIOGRAPHS IS PRIMARILY DUE TO LEFT ATRIAL ENLARGEMENT.  

PubMed

Conflicting information has been published regarding the cause of a valentine-shaped cardiac silhouette in dorsoventral or ventrodorsal thoracic radiographs in cats. The purpose of this retrospective, cross-sectional study was to test the hypothesis that the valentine shape is primarily due to left atrial enlargement. Images for cats with a radiographic valentine-shaped cardiac silhouette and full echocardiography examination were retrieved and independently reviewed. A subjective scoring system was used to record severity of radiographic valentine shape. Subjective radiographic evidence of left atrial enlargement in a radiographic lateral projection and a final diagnosis based on medical records were also recorded. A total of 81 cats met inclusion criteria. There was a strong positive correlation (P < 0.001) between echocardiographic left atrial size and severity of radiographic valentine shape. There was no effect of echocardiographic right atrial size on the severity of valentine shape, except when concurrent with severe left atrial enlargement. In this situation, right atrial enlargement increased the likelihood of observing a severe valentine shape. There was no effect of right atrial enlargement on the shape of the cardiac silhouette when left atrial enlargement was absent or only mild to moderate. There was no correlation between the category of final diagnosis of cardiac disease and the severity of valentine shape. Findings from this study supported the hypothesis that a valentine-shaped cardiac silhouette in radiographs is due primarily to left atrial enlargement in cats, with right atrial enlargement only impacting the shape if concurrent with severe left atrial enlargement. PMID:25404557

Oura, Trisha J; Young, Aisha N; Keene, Bruce W; Robertson, Ian D; Jennings, Dennis E; Thrall, Donald E

2014-11-18

44

Left ventricular diastolic dysfunction of the cardiac surgery patient; a point of view for the cardiac surgeon and cardio-anesthesiologist  

PubMed Central

Background Left ventricular diastolic dysfunction (DD) is defined as the inability of the ventricle to fill to a normal end-diastolic volume, both during exercise as well as at rest, while left atrial pressure does not exceed 12 mm Hg. We examined the concept of left ventricular diastolic dysfunction in a cardiac surgery setting. Materials and methods Literature review was carried out in order to identify the overall experience of an important and highly underestimated issue: the unexpected adverse outcome due to ventricular stiffness, following cardiac surgery. Results Although diverse group of patients for cardiac surgery could potentially affected from diastolic dysfunction, there are only few studies looking in to the impact of DD on the postoperative outcome; Trans-thoracic echo-cardiography (TTE) is the main stay for the diagnosis of DD. Intraoperative trans-oesophageal (TOE) adds to the management. Subgroups of DD can be defined with prognostic significance. Conclusion DD with elevated left ventricular end-diastolic pressure can predispose to increased perioperative mortality and morbidity. Furthermore, DD is often associated with systolic dysfunction, left ventricular hypertrophy or indeed pulmonary hypertension. When the diagnosis of DD is made, peri-operative attention to this group of patients becomes mandatory. PMID:19930694

2009-01-01

45

Cardiac resynchronization therapy: Dire need for targeted left ventricular lead placement and optimal device programming  

PubMed Central

Cardiac resynchronization therapy (CRT) effected via biventricular pacing has been established as prime therapy for heart failure patients of New York Heart Association functional class II, III and ambulatory IV, reduced left ventricular (LV) function, and a widened QRS complex. CRT has been shown to improve symptoms, LV function, hospitalization rates, and survival. In order to maximize the benefit from CRT and reduce the number of non-responders, consideration should be given to target the optimal site for LV lead implantation away from myocardial scar and close to the latest LV site activation; and also to appropriately program the device paying particular attention to optimal atrioventricular and interventricular intervals. We herein review current data related to both optimal LV lead placement and device programming and their effects on CRT clinical outcomes. PMID:25548617

Pastromas, Sokratis; Manolis, Antonis S

2014-01-01

46

Natakalim improves post-infarction left ventricular remodeling by restoring the coordinated balance between endothelial function and cardiac hypertrophy.  

PubMed

Endothelial dysfunction can lead to congestive heart failure and the activation of endothelial ATP-sensitive potassium (K(ATP)) channels may contribute to endothelial protection. Therefore, the present study was carried out to investigate the hypothesis that natakalim, a novel K(ATP) channel opener, ameliorates post-infarction left ventricular remodeling and failure by correcting endothelial dysfunction. The effects of myocardial infarction were assessed 8 weeks following left anterior descending coronary artery occlusion in male Wistar rats. Depressed blood pressure, cardiac dysfunction, evidence of left ventricular remodeling and congestive heart failure were observed in the rats with myocardial infarction. Treatment with natakalim at daily oral doses of 1, 3 or 9 mg/kg/day for 8 weeks prevented these changes. Natakalim also prevented the progression to cardiac failure, which was demonstrated by the increase in right ventricular weight/body weight (RVW/BW) and relative lung weight, signs of cardiac dysfunction, as well as the overexpression of atrial and brain natriuretic peptide mRNAs. Our results also demonstrated that natakalim enhanced the downregulation of endothelium-derived nitric oxide, attenuated the upregulation of inducible nitric oxide synthase-derived nitric oxide (NO), inhibited the upregulated endothelin system and corrected the imbalance between prostacyclin and thromboxane A(2). Overall, our findings suggest that natakalim prevents post-infarction hypertrophy and cardiac failure by restoring the coordinated balance between endothelial function and cardiac hypertrophy. PMID:25215478

Zhou, Hong-Min; Zhong, Ming-Li; Zhang, Yan-Fang; Cui, Wen-Yu; Long, Chao-Liang; Wang, Hai

2014-11-01

47

Natakalim improves post-infarction left ventricular remodeling by restoring the coordinated balance between endothelial function and cardiac hypertrophy  

PubMed Central

Endothelial dysfunction can lead to congestive heart failure and the activation of endothelial ATP-sensitive potassium (KATP) channels may contribute to endothelial protection. Therefore, the present study was carried out to investigate the hypothesis that natakalim, a novel KATP channel opener, ameliorates post-infarction left ventricular remodeling and failure by correcting endothelial dysfunction. The effects of myocardial infarction were assessed 8 weeks following left anterior descending coronary artery occlusion in male Wistar rats. Depressed blood pressure, cardiac dysfunction, evidence of left ventricular remodeling and congestive heart failure were observed in the rats with myocardial infarction. Treatment with natakalim at daily oral doses of 1, 3 or 9 mg/kg/day for 8 weeks prevented these changes. Natakalim also prevented the progression to cardiac failure, which was demonstrated by the increase in right ventricular weight/body weight (RVW/BW) and relative lung weight, signs of cardiac dysfunction, as well as the overexpression of atrial and brain natriuretic peptide mRNAs. Our results also demonstrated that natakalim enhanced the downregulation of endothelium-derived nitric oxide, attenuated the upregulation of inducible nitric oxide synthase-derived nitric oxide (NO), inhibited the upregulated endothelin system and corrected the imbalance between prostacyclin and thromboxane A2. Overall, our findings suggest that natakalim prevents post-infarction hypertrophy and cardiac failure by restoring the coordinated balance between endothelial function and cardiac hypertrophy. PMID:25215478

ZHOU, HONG-MIN; ZHONG, MING-LI; ZHANG, YAN-FANG; CUI, WEN-YU; LONG, CHAO-LIANG; WANG, HAI

2014-01-01

48

Left Ventricular Flow Analysis: Recent Advances in Numerical Methods and Applications in Cardiac Ultrasound  

PubMed Central

The left ventricle (LV) pumps oxygenated blood from the lungs to the rest of the body through systemic circulation. The efficiency of such a pumping function is dependent on blood flow within the LV chamber. It is therefore crucial to accurately characterize LV hemodynamics. Improved understanding of LV hemodynamics is expected to provide important clinical diagnostic and prognostic information. We review the recent advances in numerical and experimental methods for characterizing LV flows and focus on analysis of intraventricular flow fields by echocardiographic particle image velocimetry (echo-PIV), due to its potential for broad and practical utility. Future research directions to advance patient-specific LV simulations include development of methods capable of resolving heart valves, higher temporal resolution, automated generation of three-dimensional (3D) geometry, and incorporating actual flow measurements into the numerical solution of the 3D cardiovascular fluid dynamics. PMID:23690874

Borazjani, Iman; Westerdale, John; McMahon, Eileen M.; Rajaraman, Prathish K.; Heys, Jeffrey J.

2013-01-01

49

The relationship between ventricular electrical delay and left ventricular remodelling with cardiac resynchronization therapy  

PubMed Central

Aims The aim of the present study was to evaluate the relationship between left ventricular (LV) electrical delay, as measured by the QLV interval, and outcomes in a prospectively designed substudy of the SMART-AV Trial. Methods and results This was a multicentre study of patients with advanced heart failure undergoing cardiac resynchronization therapy (CRT) defibrillator implantation. In 426 subjects, QLV was measured as the interval from the onset of the QRS from the surface ECG to the first large peak of the LV electrogram. Left ventricular volumes were measured by echocardiography at baseline and after 6 months of CRT by a blinded core laboratory. Quality of life (QOL) was assessed by a standardized questionnaire. When separated by quartiles based on QLV duration, reverse remodelling response rates (>15% reduction in LV end systolic volume) increased progressively from 38.7 to 68.4% and QOL response rate (>10 points reduction) increased from 50 to 72%. Patients in the highest quartile of QLV had a 3.21-fold increase (1.58–6.50, P = 0.001) in their odds of a reverse remodelling response after correcting for QRS duration, bundle branch block type, and clinical characteristics by multivariate logistic regression analysis. Conclusion Electrical dyssynchrony, as measured by QLV, was strongly and independently associated with reverse remodelling and QOL with CRT. Acute measurements of QLV may be useful to guide LV lead placement. PMID:21875862

Gold, Michael R.; Birgersdotter-Green, Ulrika; Singh, Jagmeet P.; Ellenbogen, Kenneth A.; Yu, Yinghong; Meyer, Timothy E.; Seth, Milan; Tchou, Patrick J.

2011-01-01

50

Effect of cardiac resynchronization therapy on left ventricular diastolic function: implications for clinical outcome.  

PubMed

Background: The definition of response to cardiac resynchronization therapy (CRT) remains controversial,with variable rates of response depending on the criteria used. Our aim was to analyze the impact of CRT on diastolic function in different degrees of response, particularly in patients with positive clinical but no echocardiographic response.Methods and Results: In 250 CRT patients clinical evaluation and echocardiography were performed before and after CRT. Absolute response to CRT was defined as a reduction in left ventricular (LV)end-systolic volume of ? 15% at 1-year follow-up. Additionally, patients were classified into 4 subgroups according to their amount of response: extensive reverse remodeling (RR), slight RR, clinical response without RR, and neither clinical response nor RR. An improvement in estimates of LV filling pressure and a decrease in left atrial dimensions were observed only in responders to CRT. Patients with clinical but no echocardiographic response had significant improvement in E-wave and deceleration time and nonsignificant improvement in other parameters.Conclusions: LV diastolic function improves with CRT. Clinical responders without echocardiographic response show improvement in parameters of diastolic function. That suggests that clinical-only response to CRT is secondary to a real effect of the therapy, rather than a placebo effect. PMID:25089305

Doltra, Adelina; Bijnens, Bart; Tolosana, José María; Gabrielli, Luigi; Castel, María Ángeles; Berruezo, Antonio; Brugada, Josep; Mont, Lluís; Sitges, Marta

2014-05-01

51

The Effects of Training on the Time Components of the Left Ventricle, and Cardiac Time Components: Sedentary versus Active Individuals.  

ERIC Educational Resources Information Center

A review of previous research was completed to determine (a) the response of the cardiac time components of the left ventricle to varying types and intensities of training programs, (b) the probable physiological explanations for these responses, and (c) the significance of the changes which did or did not occur. It was found that, at rest,…

Plowman, Sharon Ann

52

Left ventricular geometric remodeling in relation to non-ischemic scar pattern on cardiac magnetic resonance imaging.  

PubMed

Left ventricular (LV) remodeling and myocardial fibrosis have been linked to adverse heart failure outcomes. Mid wall late gadolinium enhancement (MW-LGE) on cardiac magnetic resonance (CMR) imaging is well-associated with non-ischemic cardiomyopathy (NICM), but prevalence in ischemic cardiomyopathy (ICM) and association with remodeling are unknown. The population comprised patients with systolic dysfunction [LV ejection fraction (LVEF ? 40 %)]. CMR was used to identify MW-LGE, conventionally defined as fibrosis of the mid-myocardial or epicardial aspect of the LV septum. 285 patients were studied. MW-LGE was present in 12 %, and was tenfold more common with NICM (32 %) versus ICM (3 %, p < 0.001). However, owing to higher prevalence of ICM, 15 % of patients with MW-LGE had ICM. LV wall stress was higher (p = 0.02) among patients with, versus those without, MW-LGE despite similar systolic blood pressure (p = 0.24). In multivariate analysis, MW-LGE was associated with CMR-quantified LV end-diastolic volume (p = 0.03) independent of LVEF and mass. Incorporation of clinical and imaging variables demonstrated MW-LGE to be associated with higher LV end-diastolic volume (OR 1.13, CI 1.004-1.27 per 10 ml/m(2), p = 0.04) after controlling for presence of NICM (OR 16.0, CI 5.8-44.1, p < 0.001). While more common in NICM, MW-LGE can occur in ICM and is a marker of LV chamber dilation irrespective of cardiomyopathic etiology. PMID:25008088

Kim, Jiwon; Kochav, Jonathan D; Gurevich, Sergey; Afroz, Anika; Petashnick, Maya; Volo, Samuel; Diaz, Belen; Okin, Peter M; Horn, Evelyn; Devereux, Richard B; Weinsaft, Jonathan W

2014-12-01

53

Left Ventricular Geometric Remodeling in Relation to Non-Ischemic Scar Pattern on Cardiac Magnetic Resonance Imaging  

PubMed Central

Purpose Left ventricular (LV) remodeling and myocardial fibrosis have been linked to adverse heart failure outcomes. Mid wall late gadolinium enhancement (MW-LGE) on cardiac magnetic resonance (CMR) imaging is well-associated with non-ischemic cardiomyopathy (NICM), but prevalence in ischemic cardiomyopathy (ICM) and association with remodeling are unknown. Methods The population comprised patients with systolic dysfunction (LVEF?40%). CMR was used to identify MW-LGE, conventionally defined as fibrosis of the mid-myocardial or epicardial aspect of the LV septum. Results 285 patients were studied. MW-LGE was present in 12%, and was 10-fold more common with NICM (32%) vs. ICM (3%, p<0.001). However, owing to higher prevalence of ICM, 15% of patients with MW-LGE had ICM. LV wall stress was higher (p=0.02) among patients with, vs. those without, MW-LGE despite similar systolic blood pressure (p=0.24). In multivariate analysis, MW-LGE was associated with CMR-quantified LV end-diastolic volume (p=0.03) independent of LVEF and mass. Incorporation of clinical and imaging variables demonstrated MW-LGE to be associated with higher LV end-diastolic volume (OR=1.13 [CI 1.004–1.27] per 10 ml/m2, p=0.04) after controlling for presence of NICM (OR=16.0 [CI 5.8–44.1], p<0.001). Conclusions While more common in NICM, MW-LGE can occur in ICM and is a marker of LV chamber dilation irrespective of cardiomyopathic etiology. PMID:25008088

Kim, Jiwon; Kochav, Jonathan D.; Gurevich, Sergey; Afroz, Anika; Petashnick, Maya; Volo, Samuel; Diaz, Belen; Okin, Peter M.; Horn, Evelyn; Devereux, Richard B.; Weinsaft, Jonathan W.

2014-01-01

54

Segmentation of left atrial intracardiac ultrasound images for image guided cardiac ablation therapy  

NASA Astrophysics Data System (ADS)

Intracardiac echocardiography (ICE), a technique in which structures of the heart are imaged using a catheter navigated inside the cardiac chambers, is an important imaging technique for guidance in cardiac ablation therapy. Automatic segmentation of these images is valuable for guidance and targeting of treatment sites. In this paper, we describe an approach to segment ICE images by generating an empirical model of blood pool and tissue intensities. Normal, Weibull, Gamma, and Generalized Extreme Value (GEV) distributions are fit to histograms of tissue and blood pool pixels from a series of ICE scans. A total of 40 images from 4 separate studies were evaluated. The model was trained and tested using two approaches. In the first approach, the model was trained on all images from 3 studies and subsequently tested on the 40 images from the 4th study. This procedure was repeated 4 times using a leave-one-out strategy. This is termed the between-subjects approach. In the second approach, the model was trained on 10 randomly selected images from a single study and tested on the remaining 30 images in that study. This is termed the within-subjects approach. For both approaches, the model was used to automatically segment ICE images into blood and tissue regions. Each pixel is classified using the Generalized Liklihood Ratio Test across neighborhood sizes ranging from 1 to 49. Automatic segmentation results were compared against manual segmentations for all images. In the between-subjects approach, the GEV distribution using a neighborhood size of 17 was found to be the most accurate with a misclassification rate of approximately 17%. In the within-subjects approach, the GEV distribution using a neighborhood size of 19 was found to be the most accurate with a misclassification rate of approximately 15%. As expected, the majority of misclassified pixels were located near the boundaries between tissue and blood pool regions for both methods.

Rettmann, M. E.; Stephens, T.; Holmes, D. R.; Linte, C.; Packer, D. L.; Robb, R. A.

2013-03-01

55

Left Ventricular Hypertrophy in New Hemodialysis Patients without Symptomatic Cardiac Disease  

PubMed Central

Background and objectives: Although left ventricular hypertrophy (LVH) is a characteristic finding in hemodialysis (HD) populations, few risk factors for progressive LVH have been identified. Design, setting, participants, & measurements: As part of a multinational, blinded, randomized, controlled trial that demonstrated no effect of hemoglobin targets on LV size, 596 incident HD patients, without symptomatic cardiac disease or cardiac dilation, had baseline echocardiograms within 18 months of starting dialysis and subsequently at 24, 48, and 96 weeks later. A wide array of baseline risk factors were assessed, as were BP and hemoglobin levels during the trial. Results: The median age and duration of dialysis were 51.5 years and 9 months, respectively. LV mass index (LVMI) rose substantially during follow-up (114.2 g/m2 at baseline, 121 at week 48, 123.4 at week 48, and 128.3 at week 96), as did fractional shortening, whereas LV volume (68.7, 70.1, 68.7, and 68.1 ml/m2) and E/A ratio remained unchanged. At baseline, the only multivariate associations of LVMI were gender and N terminal pro–B type natriuretic peptide. Comparing first and last echocardiograms in those without LVH at baseline, independent predictors of increase in LVMI were higher time-integrated systolic BP and cause of ESRD. An unadjusted association between baseline LVMI and subsequent cardiovascular events or death was eliminated by adjusting for age, diabetes, systolic BP, and N terminal pro–B type natriuretic peptide. Conclusions: Progressive concentric LVH and hyperkinesis occur in HD patients, which is partly explained by hypertension but not by a wide array of potential risk factors, including anemia. PMID:20378644

Foley, Robert N.; Curtis, Bryan M.; Randell, Edward W.

2010-01-01

56

Global cardiac alterations detected by speckle-tracking echocardiography in Fabry disease: left ventricular, right ventricular, and left atrial dysfunction are common and linked to worse symptomatic status.  

PubMed

The aim of this study was to test the hypothesis that in patients with Fabry disease, 2D speckle-tracking echocardiography (2DSTE) could detect functional myocardial alterations such as left ventricular (LV), right ventricular (RV), and left atrial (LA) dysfunction, even when conventional cardiac measurements are normal. In addition, we hypothesized that these global cardiac alterations could be linked to worse symptomatic status in these patients. Fifty patients with Fabry disease and a control group of 118 healthy subjects of similar age and gender were included. The myocardial function and structural changes of the LV, RV, and LA were analyzed by 2DSTE and cardiac magnetic resonance imaging. Patients with Fabry disease had significantly lower functional myocardial values of the LV, RV, and LA than healthy subjects (LV, RV, and LA strain -18.1 ± 4.0, -21.4 ± 4.9, and 29.7 ± 9.9 % vs. -21.6 ± 2.2, -25.2 ± 4.0, and 44.8 ± 11.1 %, respectively, P < 0.001) and elevated rates of LV, RV, and LA myocardial dysfunction (24, 20, and 26 %, respectively), even when conventional cardiac measurements such as LVEF, TAPSE, and LAVI were normal. LV septal wall thickness ?15 mm, RV free wall thickness ?7 mm, and LV longitudinal dysfunction were the principal factors linked to reduced LV, RV, and LA strain, respectively. In addition, but to a lesser extent, LV and RV fibrosis were linked to reduced LV and RV strain. Patients with reduced LV, RV, and LA strain had worse functional class (dyspnea-NYHA classification) than those with normal cardiac function. In conclusion, in patients with Fabry disease, 2DSTE analyses detect LV, RV, and LA functional myocardial alterations, even when conventional cardiac measurements are normal. These functional myocardial alterations are common and significantly associated with worse symptomatic status in Fabry patients. Therefore, these findings provide important evidence to introduce global myocardial analyses using 2DSTE in the early detection of functional cardiac alterations in Fabry disease. PMID:25315709

Morris, Daniel A; Blaschke, Daniela; Canaan-Kühl, Sima; Krebs, Alice; Knobloch, Gesine; Walter, Thula C; Haverkamp, Wilhelm

2014-10-15

57

The clinical dilemma of quantifying mechanical left ventricular dyssynchrony for cardiac resynchronization therapy: segmental or global?  

PubMed

Heart failure (HF) represents a serious clinical and public cause of mortality, morbidity, as well as healthcare expenditures. Guidelines for treatment of HF join in recommending multimedical regimen at targeted doses as the best medical strategy, despite that a significant percentage of patients remain symptomatic. Studies have shown that these patients might benefit from cardiac resynchronization therapy (CRT), particularly those presenting with broad QRS duration, >135 msec. Trials have already shown that CRT results in improved morbidity and survival of these patients particularly those in New York Heart Association class III-IV HF, but almost 30% do not show any symptomatic or survival benefit, hence are classified as nonresponders. Exhaustive efforts have been made in using noninvasive methods of assessing left ventricle (LV) dyssynchrony in predicting nonresponders to CRT, including Doppler echocardiography, magnetic resonance imaging, and even single photon emission computed tomography analysis, but only with modest success. In this report, we aimed to review the available evidence for assessing markers of mechanical LV dyssynchrony by various echocardiographic modalities and their respective strength in predicting favorable response to CRT treatment, comparing global with segmental ones. While the accuracy of segmental markers of dyssynchrony in predicting satisfactory response to CRT remains controversial because of various technical limitations, global markers seem easier to measure, reproducible, and potentially accurate in reflecting overall cavity response and its clinical implications. More studies are needed to qualify this proposal. PMID:25250865

Bajraktari, Gani; Henein, Michael Y

2015-01-01

58

Left Bundle Branch Block in Acute Cardiac Events: Insights From a 23-Year Registry.  

PubMed

Between 1991 and 2013, we evaluated the demographics, presentations, and final diagnosis of patients hospitalized with acute cardiac events and left bundle branch block (LBBB). Of 50 992 patients, 768 (1.5%) had LBBB. Compared with non-LBBB patients, patients with LBBB were mostly older, female, diabetic, and had hypertension and chronic kidney failure (CKF; P < .001 for all). Dyspnea (P < .001) and dizziness (P = .037) were more frequent in patients with LBBB. The most frequent cause of admission with LBBB was congestive heart failure (CHF; 54.2%), followed by ST-elevation myocardial infarction (STEMI; 13.3%), valvular heart disease (9.4%), unstable angina (8.3%) and Non-STEMI (7.7%). On multivariate analysis, CKF (odds ratio [OR]: 2.02, 95% confidence interval [CI]: 1.09-3.70) and LBBB (OR: 2.96, 95% CI: 2.01-4.42) were predictors of in-hospital mortality in the entire study population. Further analysis of patients with LBBB showed that CKF (OR: 2.93, 95% CI: 1.40-6.12) was the only predictor of in-hospital mortality. Regardless the presenting symptoms, CHF was the final diagnosis in most cases with LBBB. PMID:25477500

Alkindi, Fahad; El-Menyar, Ayman; Al-Suwaidi, Jassim; Patel, Ashfaq; Gehani, Abdurrazzak A; Singh, Rajvir; Albinali, Hajar; Arabi, Abdulrahman

2014-12-01

59

MDCT Venography Evaluation of a Rare Collateral Vein Draining from the Left Subclavian Vein to the Great Cardiac Vein  

PubMed Central

Congenital vascular anomalies of the venous drainage in the chest affect both cardiac and non-cardiac structures. Collateral venous drainage from the left subclavian vein to the great cardiac vein is a rare venous drainage pattern. These anomalies present a diagnostic challenge. Multi-detector computed tomography (MDCT) is useful in the diagnosis and treatment planning of these clinically complex disorders. We present a case report of an 18-year-old Caucasian male who came to our institute for evaluation of venous drainage patterns to the heart. We describe the contrast technique of bilateral dual injection MDCT venography and the imaging features of the venous drainage patterns to the heart. PMID:25379351

Abchee, Antoine; Saade, Charbel; Al-Mohiy, Hussain; El-Merhi, Fadi

2014-01-01

60

Rupture of a giant cardiac hydatid cyst in the left ventricular free wall: successful surgical management of a rare entity.  

PubMed

Hydatid cyst of heart is a rare but potentially fatal site of pathology, especially left ventricular free wall. We managed a successful surgical treatment on a case of a 24 year old man who had a giant cardiac hydatid cyst (71 x 64 mm) that ruptured left ventricular free wall. The cyst was excised gently and all the cystic materials were removed, the cyst cavity was closed with GORE-TEX soft tissue patch. The patient was discharged on the 9th postoperative day without symptoms. This case is different from other cardiac hydatid cysts that have been reported in literature previously; because this patient was young and had advanced phase of the disease that presented to our clinic lately. Additionally, the cyst had limited both ventricular volumes significantly. PMID:23785588

Hosseinian, Adallat; Mohammadzadeh, Alireza; Shahmohammadi, Ghader; Hasanpour, Mohammad; Maleki, Nasrollah; Doustkami, Hossein; Haghdoost, Zarafshan

2013-01-01

61

Association Between Tangential Beam Treatment Parameters and Cardiac Abnormalities After Definitive Radiation Treatment for Left-Sided Breast Cancer  

SciTech Connect

Purpose: To examine the association between radiation treatment (RT) parameters, cardiac diagnostic test abnormalities, and clinical cardiovascular diagnoses among patients with left-sided breast cancer after breast conservation treatment with tangential beam RT. Methods and Materials: The medical records of 416 patients treated between 1977 and 1995 with RT for primary left-sided breast cancer were reviewed for myocardial perfusion imaging and echocardiograms. Sixty-two patients (62/416, 15%) underwent these cardiac diagnostic tests for cardiovascular symptoms and were selected for further study. Central lung distance and maximum heart width and length in the treatment field were determined for each patient. Medical records were reviewed for cardiovascular diagnoses and evaluation of cardiac risk factors. Results: At a median of 12 years post-RT the incidence of cardiac diagnostic test abnormalities among symptomatic left-sided irradiated women was significantly higher than the predicted incidence of cardiovascular disease in the patient population, 6/62 (9%) predicted vs. 24/62 (39%) observed, p 0.001. As compared with patients with normal tests, patients with cardiac diagnostic test abnormalities had a larger median central lung distance (2.6 cm vs. 2.2 cm, p = 0.01). Similarly, patients with vs. without congestive heart failure had a larger median central lung distance (2.8 cm vs. 2.3 cm, p = 0.008). Conclusions: Contemporary RT for early breast cancer may be associated with a small, but potentially avoidable, risk of cardiovascular morbidity that is associated with treatment technique.

Correa, Candace R. [Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA (United States); Das, Indra J. [Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA (United States)], E-mail: Das@xrt.upenn.edu; Litt, Harold I. [Department of Radiology-Cardiovascular Imaging Section, University of Pennsylvania, Philadelphia, PA (United States); Ferrari, Victor [Department of Medicine-Division of Cardiovascular Medicine, University of Pennsylvania, Philadelphia, PA (United States); Hwang, W.-T. [Center for Clinical Epidemiology and Biostatistics, University of Pennsylvania, Philadelphia, PA (United States); Solin, Lawrence J.; Harris, Eleanor E. [Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA (United States)

2008-10-01

62

Diastolic chamber properties of the left ventricle assessed by global fitting of pressure-volume data: improving the gold standard of diastolic function  

PubMed Central

In cardiovascular research, relaxation and stiffness are calculated from pressure-volume (PV) curves by separately fitting the data during the isovolumic and end-diastolic phases (end-diastolic PV relationship), respectively. This method is limited because it assumes uncoupled active and passive properties during these phases, it penalizes statistical power, and it cannot account for elastic restoring forces. We aimed to improve this analysis by implementing a method based on global optimization of all PV diastolic data. In 1,000 Monte Carlo experiments, the optimization algorithm recovered entered parameters of diastolic properties below and above the equilibrium volume (intraclass correlation coefficients = 0.99). Inotropic modulation experiments in 26 pigs modified passive pressure generated by restoring forces due to changes in the operative and/or equilibrium volumes. Volume overload and coronary microembolization caused incomplete relaxation at end diastole (active pressure > 0.5 mmHg), rendering the end-diastolic PV relationship method ill-posed. In 28 patients undergoing PV cardiac catheterization, the new algorithm reduced the confidence intervals of stiffness parameters by one-fifth. The Jacobian matrix allowed visualizing the contribution of each property to instantaneous diastolic pressure on a per-patient basis. The algorithm allowed estimating stiffness from single-beat PV data (derivative of left ventricular pressure with respect to volume at end-diastolic volume intraclass correlation coefficient = 0.65, error = 0.07 ± 0.24 mmHg/ml). Thus, in clinical and preclinical research, global optimization algorithms provide the most complete, accurate, and reproducible assessment of global left ventricular diastolic chamber properties from PV data. Using global optimization, we were able to fully uncouple relaxation and passive PV curves for the first time in the intact heart. PMID:23743396

Yotti, Raquel; del Villar, Candelas Pérez; del Álamo, Juan C.; Rodríguez-Pérez, Daniel; Martínez-Legazpi, Pablo; Benito, Yolanda; Carlos Antoranz, J.; Mar Desco, M.; González-Mansilla, Ana; Barrio, Alicia; Elízaga, Jaime; Fernández-Avilés, Francisco

2013-01-01

63

Association of Cardiac Troponin T With Left Ventricular Structure and Function in CKD  

PubMed Central

Background Serum cardiac troponin T (cTnT) is associated with increased risk of heart failure and cardiovascular death in several population settings. We evaluated associations of cTnT with cardiac structural and functional abnormalities in a cohort of chronic kidney disease (CKD) patients without heart failure. Study Design Cross-sectional. Setting & Participants Chronic Renal Insufficiency Cohort (CRIC; N= 3,243) Predictor The primary predictor was cTnT. Secondary predictors included demographic and clinical characteristics, hemoglobin level, high-sensitivity C-reactive protein, and estimated glomerular filtration rate using cystatin C. Outcomes Echocardiography was used to determine left ventricular (LV) mass and LV systolic and diastolic function. Measurements Circulating cTnT was measured in stored sera using the highly sensitive assay. Logistic and linear regression models were used to examine associations of cTnT with each echocardiographic outcome. Results cTnT was detectable in 2,735 (84%) persons; the median was 13.3 (IQR, 7.7–23.8) pg/mL. Compared with undetectable cTnT (<3.0 pg/mL), the highest quartile (23.9 – 738.7 pg/mL) was associated with approximately two times as likely to experience LV hypertrophy (OR, 2.43; 95% CI, 1.44–4.09) in the fully adjusted model. cTnT had a more modest association with LV systolic dysfunction; as a log-linear variable, a significant association was present in the fully adjusted model (OR of 1.4 [95% CI, 1.1–1.7] per 1-log unit; p<0.01). There was no significant independent association between cTnT and LV diastolic dysfunction. When evaluated as a screening test, cTnT functioned only modestly for LV hypertrophy and concentric hypertrophy detection (area under the curve, 0.64 for both) with weaker areas under the curve for the other outcomes. Limitations The presence of coronary artery disease was not formally assessed using either noninvasive or angiographic techniques in this study. Conclusions In this large CKD cohort without heart failure, detectable cTnT had a strong association with LV hypertrophy, a more modest association with LV systolic dysfunction, and no association with diastolic dysfunction. These findings indicate that circulating cTnT levels in CKD are predominantly an indicator of pathological LV hypertrophy. PMID:23291148

Mishra, Rakesh K.; Li, Yongmei; DeFilippi, Christopher; Fischer, Michael J.; Yang, Wei; Keane, Martin; Chen, Jing; He, Jiang; Kallem, Radhakrishna; Horwitz, Ed; Rafey, Mohammad; Raj, Dominic S.; Go, Alan S.; Shlipak, Michael G.

2013-01-01

64

Effect of cardiac resynchronization therapy in patients without left intraventricular dyssynchrony  

PubMed Central

Aims To evaluate the effects of cardiac resynchronization therapy (CRT) on long-term survival of patients without baseline left ventricular (LV) mechanical dyssynchrony. Methods and results A total of 290 heart failure patients (age 67 ± 10 years, 77% males) without significant baseline LV dyssynchrony (<60 ms as assessed with tissue Doppler imaging) were treated with CRT. Patients were divided according to the median LV dyssynchrony measured after 48 h of CRT into two groups. All-cause mortality was compared between the subgroups. In addition, the all-cause mortality rates of these subgroups were compared with the all-cause mortality of 290 heart failure patients treated with CRT who showed significant LV dyssynchrony (?60 ms) at baseline. In the group of patients without significant LV dyssynchrony, median LV dyssynchrony increased from 22 ms (inter-quartile range 16–34 ms) at baseline to 40 ms (24–56 ms) 48 h after CRT. The cumulative mortality rates at 1-, 2-, and 3-year follow-up of patients with LV dyssynchrony ?40 ms 48 h after CRT implantation were significantly higher when compared with patients with LV dyssynchrony <40 ms (10, 17, and 23 vs. 3, 8, and 10%, respectively; log-rank P< 0.001). Finally, the cumulative mortality rates at 1-, 2-, and 3-year follow-up of patients with baseline LV dyssynchrony were 3, 8, and 11%, respectively (log-rank P= 0.375 vs. patients with LV dyssynchrony <40 ms). Induction of LV dyssynchrony after CRT was an independent predictor of mortality (hazard ratio: 1.247; P= 0.009). Conclusion In patients without significant LV dyssynchrony, the induction of LV dyssynchrony after CRT may be related to a less favourable long-term outcome. PMID:22279110

Auger, Dominique; Bleeker, Gabe B.; Bertini, Matteo; Ewe, See H.; van Bommel, Rutger J.; Witkowski, Tomasz G.; Ng, Arnold C.T.; van Erven, Lieselot; Schalij, Martin J.; Bax, Jeroen J.; Delgado, Victoria

2012-01-01

65

Left ventricular modelling: a quantitative functional assessment tool based on cardiac magnetic resonance imaging  

PubMed Central

We present the development and testing of a semi-automated tool to support the diagnosis of left ventricle (LV) dysfunctions from cardiac magnetic resonance (CMR). CMR short-axis images of the LVs were obtained in 15 patients and processed to detect endocardial and epicardial contours and compute volume, mass and regional wall motion (WM). Results were compared with those obtained from manual tracing by an expert cardiologist. Nearest neighbour tracking and finite-element theory were merged to calculate local myocardial strains and torsion. The method was tested on a virtual phantom, on a healthy LV and on two ischaemic LVs with different severity of the pathology. Automated analysis of CMR data was feasible in 13/15 patients: computed LV volumes and wall mass correlated well with manually extracted data. The detection of regional WM abnormalities showed good sensitivity (77.8%), specificity (85.1%) and accuracy (82%). On the virtual phantom, computed local strains differed by less than 14 per cent from the results of commercial finite-element solver. Strain calculation on the healthy LV showed uniform and synchronized circumferential strains, with peak shortening of about 20 per cent at end systole, progressively higher systolic wall thickening going from base to apex, and a 10° torsion. In the two pathological LVs, synchronicity and homogeneity were partially lost, anomalies being more evident for the more severely injured LV. Moreover, LV torsion was dramatically reduced. Preliminary testing confirmed the validity of our approach, which allowed for the fast analysis of LV function, even though future improvements are possible. PMID:22670208

Conti, C. A.; Votta, E.; Corsi, C.; De Marchi, D.; Tarroni, G.; Stevanella, M.; Lombardi, M.; Parodi, O.; Caiani, E. G.; Redaelli, A.

2011-01-01

66

Risk stratification after myocardial infarction: is left ventricular ejection fraction enough to prevent sudden cardiac death?  

PubMed

Patients who have experienced a myocardial infarction (MI) are at increased risk of sudden cardiac death (SCD). With the advent of implantable cardioverter-defibrillators (ICDs), accurate risk stratification has become very relevant. Numerous investigations have proven that a reduced left ventricular ejection fraction (LVEF) significantly increases the SCD risk. Furthermore, ICD implantation in patients with reduced LVEF confers significant survival benefit. As a result, LVEF is the cornerstone of current decision making for prophylactic ICD implantation after MI. However, LVEF as standalone risk stratifier has major limitations: (i) the majority of SCD cases occur in patients with preserved or moderately reduced LVEF, (ii) only relatively few patients with reduced LVEF will benefit from an ICD (most will never experience a threatening arrhythmic event, others have a high risk for non-sudden death), (iii) a reduced LVEF is a risk factor for both sudden and non-sudden death. Several other non-invasive and invasive risk stratifiers, such as ventricular ectopy, QRS duration, signal-averaged electrocardiogram, microvolt T-wave alternans, markers of autonomic tone as well as programmed ventricular stimulation, have been evaluated. However, none of these techniques has unequivocally demonstrated the efficacy when applied alone or in combination with LVEF. Apart from their limited sensitivity, most of them are risk factors for both sudden and non-sudden death. Considering the multiple mechanisms involved in SCD, it seems unlikely that a single test will prove adequate for all patients. A combination of clinical characteristics with selected stratification tools may significantly improve risk stratification in the future. PMID:23644180

Dagres, Nikolaos; Hindricks, Gerhard

2013-07-01

67

Correlation-based discrimination between cardiac tissue and blood for segmentation of the left ventricle in 3-D echocardiographic images.  

PubMed

For automated segmentation of 3-D echocardiographic images, incorporation of temporal information may be helpful. In this study, optimal settings for calculation of temporal cross-correlations between subsequent time frames were determined, to obtain the maximum cross-correlation (MCC) values that provided the best contrast between blood and cardiac tissue over the entire cardiac cycle. Both contrast and boundary gradient quality measures were assessed to optimize MCC values with respect to signal choice (radiofrequency or envelope data) and axial window size. Optimal MCC values were incorporated into a deformable model to automatically segment the left ventricular cavity. MCC values were tested against, and combined with, filtered, demodulated radiofrequency data. Results reveal that using envelope data in combination with a relatively small axial window (0.7-1.25 mm) at fine scale results in optimal contrast and boundary gradient between the two tissues over the entire cardiac cycle. Preliminary segmentation results indicate that incorporation of MCC values has additional value for automated segmentation of the left ventricle. PMID:24412178

Saris, Anne E C M; Nillesen, Maartje M; Lopata, Richard G P; de Korte, Chris L

2014-03-01

68

Recommendations for cardiac chamber quantification by echocardiography in adults: an update from the american society of echocardiography and the European association of cardiovascular imaging.  

PubMed

The rapid technological developments of the past decade and the changes in echocardiographic practice brought about by these developments have resulted in the need for updated recommendations to the previously published guidelines for cardiac chamber quantification, which was the goal of the joint writing group assembled by the American Society of Echocardiography and the European Association of Cardiovascular Imaging. This document provides updated normal values for all four cardiac chambers, including three-dimensional echocardiography and myocardial deformation, when possible, on the basis of considerably larger numbers of normal subjects, compiled from multiple databases. In addition, this document attempts to eliminate several minor discrepancies that existed between previously published guidelines. PMID:25559473

Lang, Roberto M; Badano, Luigi P; Mor-Avi, Victor; Afilalo, Jonathan; Armstrong, Anderson; Ernande, Laura; Flachskampf, Frank A; Foster, Elyse; Goldstein, Steven A; Kuznetsova, Tatiana; Lancellotti, Patrizio; Muraru, Denisa; Picard, Michael H; Rietzschel, Ernst R; Rudski, Lawrence; Spencer, Kirk T; Tsang, Wendy; Voigt, Jens-Uwe

2015-01-01

69

A patient with lung squamous cell carcinoma presenting with severe cardiac dysfunction similar to dilated cardiomyopathy with left bundle branch block induced by myocardial metastasis.  

PubMed

A patient with severe cardiac dysfunction similar to dilated cardiomyopathy expired because of lung squamous cell carcinoma. He was admitted with respiratory failure and was diagnosed with congestive heart failure due to dilated cardiomyopathy based on the chest X-ray, electrocardiography, echocardiography, and coronary angiography. Chest computed tomography showed a mass shadow in the right lower lobe, and the patient was diagnosed with lung squamous cell carcinoma by bronchoscopy. The patient expired, and the autopsy revealed that a myocardial metastasis disrupted the cardiac-conduction system without dilated cardiomyopathy in myocytes. Left bundle branch block caused by myocardial metastasis presumably induced left cardiac dysfunction. PMID:25318802

Ogino, Hirokazu; Nishimura, Naoki; Kitamura, Atsushi; Ishikawa, Genta; Okafuji, Kohei; Tomishima, Yutaka; Jinta, Torahiko; Yamazoe, Masahiro; Yang, Yang; Chohnabayashi, Naohiko

2014-01-01

70

Left ventricular dysfunction and cardiac arrhythmias are frequent in type 2 myotonic dystrophy: a case control study.  

PubMed

In contrast with Steinert's disease (DM1), type 2 muscular dystrophy (DM2) is not known to be associated with a high prevalence of cardiac involvement. Our objective was to compare the results of detailed cardiac investigations in populations of DM2 and DM1 patients, and in controls. Thirty-eight DM2 patients (17 males; age=57.1+/-15.2years) were investigated for possible heart involvement, and their results compared with 76 age-sex matched DM1 patients and 76 controls. Cardiac abnormalities were present in 15 DM2 patients, including conductive defects in 14, systolic dysfunction in 6, supraventricular arrhythmias in 6 and stroke in 5 patients and were significantly more frequent than in controls. When compared to DM1 patients, conductive defects were less frequent, supraventricular arrhythmias had similar prevalence and there was a trend towards more frequent left ventricular dysfunction in DM2 patients. Our study suggests that systematic cardiac investigations should be recommended in these patients. PMID:19481939

Wahbi, Karim; Meune, Christophe; Bécane, Henri Marc; Laforêt, Pascal; Bassez, Guillaume; Lazarus, Arnaud; Radvanyi-Hoffman, Hélène; Eymard, Bruno; Duboc, Denis

2009-07-01

71

Joint multi-object registration and segmentation of left and right cardiac ventricles in 4D cine MRI  

NASA Astrophysics Data System (ADS)

The diagnosis of cardiac function based on cine MRI requires the segmentation of cardiac structures in the images, but the problem of automatic cardiac segmentation is still open, due to the imaging characteristics of cardiac MR images and the anatomical variability of the heart. In this paper, we present a variational framework for joint segmentation and registration of multiple structures of the heart. To enable the simultaneous segmentation and registration of multiple objects, a shape prior term is introduced into a region competition approach for multi-object level set segmentation. The proposed algorithm is applied for simultaneous segmentation of the myocardium as well as the left and right ventricular blood pool in short axis cine MRI images. Two experiments are performed: first, intra-patient 4D segmentation with a given initial segmentation for one time-point in a 4D sequence, and second, a multi-atlas segmentation strategy is applied to unseen patient data. Evaluation of segmentation accuracy is done by overlap coefficients and surface distances. An evaluation based on clinical 4D cine MRI images of 25 patients shows the benefit of the combined approach compared to sole registration and sole segmentation.

Ehrhardt, Jan; Kepp, Timo; Schmidt-Richberg, Alexander; Handels, Heinz

2014-03-01

72

Serial echocardiographic left ventricular ejection fraction measurements: a tool for detecting thalassemia major patients at risk of cardiac death.  

PubMed

Cardiac damage remains a major cause of mortality among patients with thalassemia major. The detection of a lower cardiac magnetic resonance T2* (CMR-T2*) signal has been suggested as a powerful predictor of the subsequent development of heart failure. However, the lack of worldwide availability of CMR-T2* facilities prevents its widespread use for follow-up evaluations of cardiac function in thalassemia major patients, warranting the need to assess the utility of other possible procedures. In this setting, the determination of left ventricular ejection fraction (LVEF) offers an accurate and reproducible method for heart function evaluation. These findings suggest a reduction in LVEF?7%, over time, determined by 2-D echocardiography, may be considered a strong predictive tool for the detection of thalassemia major patients with increased risk of cardiac death. The reduction of LVEF?7% had higher (84.76%) predictive value. Finally, Kaplan-Meier survival curves of thalassemia major patients with LVEF?7% showed a statistically significant decreased probability of survival for heart disease (p=0.0022). However, because of limitations related to the study design, such findings should be confirmed in a large long-term prospective clinical trial. PMID:23337255

Maggio, Aurelio; Vitrano, Angela; Calvaruso, Giuseppina; Barone, Rita; Rigano, Paolo; Mancuso, Luigi; Cuccia, Liana; Capra, Marcello; Pitrolo, Lorella; Prossomariti, Luciano; Filosa, Aldo; Caruso, Vincenzo; Gerardi, Calogera; Campisi, Saveria; Cianciulli, Paolo; Elefteriou, Androulla; Angastiniotis, Michel; Hamza, Hala; Telfer, Paul; Walker, John Malcolm; Phrommintikul, Arintaya; Chattipakorn, Nipon

2013-04-01

73

Automatic Segmentation of the Left Ventricle in Cardiac MRI Using Local Binary Fitting Model and Dynamic Programming Techniques  

PubMed Central

Segmentation of the left ventricle is very important to quantitatively analyze global and regional cardiac function from magnetic resonance. The aim of this study is to develop a novel algorithm for segmenting left ventricle on short-axis cardiac magnetic resonance images (MRI) to improve the performance of computer-aided diagnosis (CAD) systems. In this research, an automatic segmentation method for left ventricle is proposed on the basis of local binary fitting (LBF) model and dynamic programming techniques. The validation experiments are performed on a pool of data sets of 45 cases. For both endo- and epi-cardial contours of our results, percentage of good contours is about 93.5%, the average perpendicular distance are about 2 mm. The overlapping dice metric is about 0.91. The regression and determination coefficient between the experts and our proposed method on the LV mass is 1.038 and 0.9033, respectively; they are 1.076 and 0.9386 for ejection fraction (EF). The proposed segmentation method shows the better performance and has great potential in improving the accuracy of computer-aided diagnosis systems in cardiovascular diseases. PMID:25500580

Hu, Huaifei; Gao, Zhiyong; Liu, Liman; Liu, Haihua; Gao, Junfeng; Xu, Shengzhou; Li, Wei; Huang, Lu

2014-01-01

74

Left ventricular restoration devices.  

PubMed

Left ventricular (LV) remodeling results in continuous cardiac chamber enlargement and contractile dysfunction, perpetuating the syndrome of heart failure. With current exhaustion of the neurohormonal medical paradigm, surgical and device-based therapies have been increasingly investigated as a way to restore LV chamber architecture and function. Left ventricular restoration has been attempted with surgical procedures, such as partial left ventriculectomy, surgical ventricular restoration with or without revascularization, and devices, such as the Acorn CorCap, the Paracor HeartNet, and the Myocor Myosplint. Whereas all these techniques require surgical access, with or without cardiopulmonary bypass, a newer ventricular partitioning device (VPD) called Parachute, can be delivered percutaneously through the aortic valve. Designed to achieve LV restoration from within the ventricle, this VPD partitions the LV by isolating aneurysmal from normal myocardium thereby diminishing the functioning cavity. This review aims to critically appraise the above methods, with particular attention to device-based therapies. PMID:24574107

Oliveira, Guilherme H; Al-Kindi, Sadeer G; Bezerra, Hiram G; Costa, Marco A

2014-04-01

75

Transvenous Biventricular Pacing for Cardiac Resynchronization Therapy in Patients with Persistent Left Superior Vena Cava and Right Superior Vena Cava Atresia  

PubMed Central

Biventricular pacing for cardiac resynchronization therapy is an effective adjunctive therapy for the treatment of symptomatic moderate and severe congestive heart failure. However, experience with transvenous cardiac resynchronization therapy in patients who have both persistent left superior vena cava and right superior vena cava atresia is extremely limited. We successfully performed cardiac resynchronization therapy in 2 patients who had persistent left superior vena cava, right superior vena cava atresia, and congestive heart failure. Our 2 cases demonstrate the possibility of a total transvenous approach for left ventricular pacing despite the presence of serious cardiac venous anomalies. This approach enables clinicians to avoid the riskier epicardial lead placement, which requires a thoracotomy under general anesthesia. PMID:18427654

Lopez, J. Alberto

2008-01-01

76

Left ventricular diastolic function in workers occupationally exposed to mercury vapour without clinical presentation of cardiac involvement  

SciTech Connect

The aim of the study was to evaluate left ventricular diastolic function in workers occupationally exposed to mercury vapour without clinical presentation of cardiac involvement. The studies included 115 workers (92 men and 23 women) occupationally exposed to mercury vapour without clinical presentation of cardiac involvement (mean age: 47.83 ± 8.29). Blood samples were taken to determine blood lipid profile, urine was collected to estimate mercury concentration (Hg-U) and echocardiographic examination was performed to evaluate diastolic function of the left ventricle. In the entire group of workers occupationally exposed to mercury vapour without clinical presentation of cardiac involvement, Spearman correlations analysis demonstrated the following significant linear relationships: between body mass index (BMI) and ratio of maximal early diastolic mitral flow velocity/early diastolic mitral annular velocity (E/E') (r = 0.32, p < 0.05), between serum HDL concentration and E/E' (r = ? 0.22, p < 0.05), between Hg-U and E/E' (r = 0.35, p < 0.05), between Hg-U and isovolumetric relaxation time (IVRT') (r = 0.41, p < 0.05), between Hg-U and ratio of maximal early diastolic mitral flow velocity/maximal late diastolic mitral flow velocity (E/A) (r = ? 0.31, p < 0.05) and between serum HDL concentration and E/A (r = 0.43, p < 0,05). In logistic regression analysis it as shown that independent factors of left ventricular diastolic dysfunction risk in the study group included a higher urine mercury concentration, a higher value of BMI and a lower serum HDL concentration (OR{sub Hg}-{sub U} = 1.071, OR{sub BMI} = 1.200, OR{sub HDL} = 0.896, p < 0.05). Summing up, occupational exposure to mercury vapour may be linked to impaired left ventricular diastolic function in workers without clinical presentation of cardiac involvement. -- Highlights: ? Study aimed at evaluation of LVDD in workers occupationally exposed to Hg. ? There was significant linear relationships between Hg-U and E/E'. ? Independent risk factor of LVDD in study group included higher Hg-U. ? Independent risk factor of LVDD in study group included higher BMI and lower HDL. ? Occupational exposure to Hg may be linked to LVDD.

Por?ba, Rafa?, E-mail: sogood@poczta.onet.pl; Skoczy?ska, Anna; Ga?, Pawe?; Turczyn, Barbara; Wojakowska, Anna

2012-09-15

77

Truncus Arteriosus with Persistent Left Superior Vena Cava: Cardiac Computed Tomography Findings in an Unrepaired Adult Patient  

PubMed Central

Truncus arteriosus (TA), a rare complex congenital cardiac disease in which systemic pulmonary and coronary circulations originate from a common vessel, develops due to failure of separation of the common trunk during embryonic life. In this case report, we discuss a 24-year-old patient with TA in whom a computed tomography angiography was performed. To the best of our knowledge, no case has been reported so far where an adult had combined left superior vena cava and pulmonary vein anomaly. PMID:24228215

Genç, Berhan; Okur, Faik Fevi; Tavl?, Vedide; Solak, Aynur

2013-01-01

78

Truncus arteriosus with persistent left superior vena cava: cardiac computed tomography findings in an unrepaired adult patient.  

PubMed

Truncus arteriosus (TA), a rare complex congenital cardiac disease in which systemic pulmonary and coronary circulations originate from a common vessel, develops due to failure of separation of the common trunk during embryonic life. In this case report, we discuss a 24-year-old patient with TA in whom a computed tomography angiography was performed. To the best of our knowledge, no case has been reported so far where an adult had combined left superior vena cava and pulmonary vein anomaly. PMID:24228215

Genç, Berhan; Okur, Faik Fevi; Tavl?, Vedide; Solak, Aynur

2013-01-01

79

Left Ventricular Mechanical Dyssynchrony by Cardiac Magnetic Resonance is Greater in Patients with Strict vs. Non-strict ECG Criteria for Left Bundle Branch Block  

PubMed Central

Background Left bundle branch block (LBBB) is a marker of increased delay between septal and left ventricular (LV) lateral wall electrical activation, and is a predictor of which patients will benefit from cardiac resynchronization therapy (CRT). Recent analysis has suggested that one third of patients meeting conventional ECG criteria for LBBB are misdiagnosed and new strict LBBB criteria have been proposed. We tested the hypothesis that strict LBBB patients have greater LV mechanical dyssynchrony than patients meeting non-strict LBBB criteria while there is no difference between patients with non-strict LBBB and LV conduction delay with QRS duration 110–119 ms. Methods Sixty-four patients referred for primary prevention implantable cardioverter-defibrillators (ICD) underwent 12-lead ECG and cardiac magnetic resonance (CMR) myocardial tagging. The patients were classified as strict LBBB, non-strict LBBB or non-LBBB (nonspecific LV conduction delay with QRS duration 110–119 ms). The time delay between septal and lateral LV wall peak circumferential strain (septal-to-lateral wall delay) was measured by CMR. Results Patients with strict LBBB (n=31) had a greater septal-to-lateral wall delay, compared to patients with non-strict LBBB (n=19) (210±137 ms vs. 122±102 ms, p=0.045). There was no significant difference between non-strict LBBB and non-LBBB (n=14) septal-to-lateral wall delay (122±102 ms vs. 100±86 ms, p=0.51). Conclusions Strict-LBBB criteria identify patients with greater mechanical dyssynchrony compared to patients only meeting non-strict LBBB criteria, while there was no significant difference between non-strict LBBB and non-LBBB patients. The greater observed LV dyssynchrony may explain why strict-LBBB patients have better response to CRT. PMID:23708167

Andersson, Linus G.; Wu, Katherine C.; Wieslander, Björn; Loring, Zak; Frank, Terry F.; Maynard, Charles; Gerstenblith, Gary; Tomaselli, Gordon F.; Weiss, Robert G.; Wagner, Galen S; Ugander, Martin; Strauss, David G

2013-01-01

80

Administration of Pigment Epithelium-Derived Factor Inhibits Left Ventricular Remodeling and Improves Cardiac Function in Rats with Acute Myocardial Infarction  

PubMed Central

Oxidative stress and inflammation are involved in cardiac remodeling after acute myocardial infarction (AMI). We have found that pigment epithelium-derived factor (PEDF) inhibits vascular inflammation through its anti-oxidative properties. However, effects of PEDF on cardiac remodeling after AMI remain unknown. We investigated whether PEDF could inhibit left ventricular remodeling and improve cardiac function in rats with AMI. AMI was induced in 8-week-old Sprague-Dawley rats by ligation of the left ascending coronary artery. Rats were treated intravenously with vehicle or 10 ?g PEDF/100 g b.wt. every day for up to 2 weeks after AMI. Each rat was followed until 16 weeks of age. PEDF levels in infarcted areas and serum were significantly decreased at 1 week after AMI and remained low during the observational periods. PEDF administration inhibited apoptotic cell death and oxidative stress generation around the infarcted areas at 2 and 8 weeks after AMI. Further, PEDF injection suppressed cardiac fibrosis by reducing transforming growth factor-? and type III collagen expression, improved left ventricular ejection fraction, ameliorated diastolic dysfunction, and inhibited the increase in left ventricular mass index at 8 weeks after AMI. The present study demonstrated that PEDF could inhibit tissue remodeling and improve cardiac function in AMI rats. Substitution of PEDF may be a novel therapeutic strategy for cardiac remodeling after AMI. PMID:21281791

Ueda, Shin-ichiro; Yamagishi, Sho-ichi; Matsui, Takanori; Jinnouchi, Yuko; Imaizumi, Tsutomu

2011-01-01

81

Cardiac resynchronization therapy in heart failure patients with less severe left ventricular dysfunction.  

PubMed

Cardiac resynchronization therapy is beneficial in heart failure patients with LVEF ?35% and electrical dyssynchrony. However, its effects among patients with less severe LV dysfunction have not been established. Recent post-hoc analyses of landmark CRT trials suggest that CRT benefit may be present in patients with LVEF >35% and is associated with improvement in cardiac reverse remodelling, all-cause mortality, and need for heart failure hospitalizations. This review summarizes the currently available literature regarding the potential impact of CRT in patients with more modest reductions in LVEF. PMID:25469668

Hai, Ofek Y; Mentz, Robert J; Zannad, Faiez; Gasparini, Maurizio; De Ferrari, Gaetano M; Daubert, Jean-Claude; Holzmeister, Johannes; Lam, Carolyn S P; Pochet, Thierry; Vincent, Alphons; Linde, Cecilia

2014-12-01

82

Electrical Wave Propagation in an Anisotropic Model of the Left Ventricle Based on Analytical Description of Cardiac Architecture  

PubMed Central

We develop a numerical approach based on our recent analytical model of fiber structure in the left ventricle of the human heart. A special curvilinear coordinate system is proposed to analytically include realistic ventricular shape and myofiber directions. With this anatomical model, electrophysiological simulations can be performed on a rectangular coordinate grid. We apply our method to study the effect of fiber rotation and electrical anisotropy of cardiac tissue (i.e., the ratio of the conductivity coefficients along and across the myocardial fibers) on wave propagation using the ten Tusscher–Panfilov (2006) ionic model for human ventricular cells. We show that fiber rotation increases the speed of cardiac activation and attenuates the effects of anisotropy. Our results show that the fiber rotation in the heart is an important factor underlying cardiac excitation. We also study scroll wave dynamics in our model and show the drift of a scroll wave filament whose velocity depends non-monotonically on the fiber rotation angle; the period of scroll wave rotation decreases with an increase of the fiber rotation angle; an increase in anisotropy may cause the breakup of a scroll wave, similar to the mother rotor mechanism of ventricular fibrillation. PMID:24817308

Pravdin, Sergey F.; Dierckx, Hans; Katsnelson, Leonid B.; Solovyova, Olga; Markhasin, Vladimir S.; Panfilov, Alexander V.

2014-01-01

83

A Voluntary Breath-Hold Treatment Technique for the Left Breast With Unfavorable Cardiac Anatomy Using Surface Imaging  

SciTech Connect

Purpose: Breath-hold (BH) treatments can be used to reduce cardiac dose for patients with left-sided breast cancer and unfavorable cardiac anatomy. A surface imaging technique was developed for accurate patient setup and reproducible real-time BH positioning. Methods and Materials: Three-dimensional surface images were obtained for 20 patients. Surface imaging was used to correct the daily setup for each patient. Initial setup data were recorded for 443 fractions and were analyzed to assess random and systematic errors. Real time monitoring was used to verify surface placement during BH. The radiation beam was not turned on if the BH position difference was greater than 5 mm. Real-time surface data were analyzed for 2398 BHs and 363 treatment fractions. The mean and maximum differences were calculated. The percentage of BHs greater than tolerance was calculated. Results: The mean shifts for initial patient setup were 2.0 mm, 1.2 mm, and 0.3 mm in the vertical, longitudinal, and lateral directions, respectively. The mean 3-dimensional vector shift was 7.8 mm. Random and systematic errors were less than 4 mm. Real-time surface monitoring data indicated that 22% of the BHs were outside the 5-mm tolerance (range, 7%-41%), and there was a correlation with breast volume. The mean difference between the treated and reference BH positions was 2 mm in each direction. For out-of-tolerance BHs, the average difference in the BH position was 6.3 mm, and the average maximum difference was 8.8 mm. Conclusions: Daily real-time surface imaging ensures accurate and reproducible positioning for BH treatment of left-sided breast cancer patients with unfavorable cardiac anatomy.

Gierga, David P., E-mail: dgierga@partners.org [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Harvard Medical School, Boston, Massachusetts (United States); Turcotte, Julie C. [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States)] [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Sharp, Gregory C. [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States) [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Harvard Medical School, Boston, Massachusetts (United States); Sedlacek, Daniel E.; Cotter, Christopher R. [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States)] [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Taghian, Alphonse G. [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States) [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Harvard Medical School, Boston, Massachusetts (United States)

2012-12-01

84

The deep inspiration breath hold technique using Abches reduces cardiac dose in patients undergoing left-sided breast irradiation  

PubMed Central

Purpose We explored whether the deep inspiration breath hold (DIBH) technique using Abches during left-sided breast irradiation was effective for minimizing the amount of radiation to the heart and lung compared to free breathing (FB). Materials and Methods Between February and July 2012, a total of 25 patients with left-sided breast cancer underwent two computed tomography scans each with the DIBH using Abches and using FB after breast-conserving surgery. The scans were retrospectively replanned using standardized criteria for the purpose of this study. The DIBH plans for each patient were compared with FB plans using dosimetric parameters. Results All patients were successfully treated with the DIBH technique using Abches. Significant differences were found between the DIBH and FB plans for mean heart dose (2.52 vs. 4.53 Gy), heart V30 (16.48 vs. 45.13 cm3), V20 (21.35 vs. 54.55 cm3), mean left anterior descending coronary artery (LAD) dose (16.01 vs. 26.26 Gy, all p < 0.001), and maximal dose to 0.2 cm3 of the LAD (41.65 vs. 47.27 Gy, p = 0.017). The mean left lung dose (7.53 vs. 8.03 Gy, p = 0.073) and lung V20 (14.63% vs. 15.72%, p = 0.060) of DIBH using Abches were not different significantly compared with FB. Conclusion We report that the use of a DIBH technique using Abches in breathing adapted radiotherapy for left-sided breast cancer is easily feasible in daily practice and significantly reduces the radiation doses to the heart and LAD, therefore potentially reducing cardiac risk. PMID:24501713

Lee, Ha Yoon; Chang, Jee Suk; Lee, Ik Jae; Park, Kwangwoo; Kim, Yong Bae; Suh, Chang Ok; Kim, Jun Won

2013-01-01

85

Chiari type I presenting as left glossopharyngeal neuralgia with cardiac syncope  

Microsoft Academic Search

.   Glossopharyngeal neuralgia is an uncommon craniofacial pain syndrome that is occasionally associated with cardiac syncope.\\u000a However, we relate Chiari I syndrome as a cause of this clinical picture for the first time in the literature. The authors\\u000a analyze the relevant literature and discuss the pathogenesis and treatment of associated syndromes. We describe the case of\\u000a a 45-year-old female patient

Paulo Henrique Aguiar; Oswaldo Tella; Carlos Pereira; Fábio Godinho; Renata Simm

2002-01-01

86

Deformable left-ventricle mesh model for motion-compensated filtering in cardiac gated SPECT  

PubMed Central

Purpose: In this article, the authors present a motion-compensated spatiotemporal processing algorithm to reduce noise in cardiac gated SPECT. Cardiac gated SPECT data are particularly noisy because the acquired photon data are divided among a number of time frames (gates). Classical spatial reconstruction and processing techniques offer noise reduction but they are usually applied on each frame separately and fail to utilize temporal correlation between frames. Methods: In this work, the authors present a motion-compensated spatiotemporal postreconstruction filter offering noise reduction while minimizing motion-blur artifacts. The proposed method can be used regardless of the type of image-reconstruction method (analytical or iterative). The between-frame volumetric myocardium motion is estimated using a deformable mesh model based on the model of the myocardial surfaces. The estimated motion is then used to perform spatiotemporal filtering along the motion trajectories. Both the motion-estimation and spatiotemporal filtering methods seek to maintain the wall brightening seen during cardiac contraction. Wall brightening is caused by the partial volume effect, which is usually viewed as an artifact; however, wall brightening is a useful signature in clinical practice because it allows the clinician to visualize wall thickening. Therefore, the authors seek in their method to preserve the brightening effect. Results: The authors find that the proposed method offers better noise reduction than several existing methods as quantitatively evaluated by signal-to-noise ratio, bias-variance plots, and ejection fraction analysis as well as on tested clinical data. Conclusions: The proposed method mitigates for noise in cardiac gated SPECT images using a postreconstruction motion-compensated filtering approach. Visual as well as quantitative evaluation show considerable improvement in image quality. PMID:21089783

Marin, Thibault; Brankov, Jovan G.

2010-01-01

87

Cardiac dose reduction with breathing adapted radiotherapy using self respiration monitoring system for left-sided breast cancer  

PubMed Central

Purpose To quantify the cardiac dose reduction during breathing adapted radiotherapy using Real-time Position Management (RPM) system in the treatment of left-sided breast cancer. Materials and Methods Twenty-two patients with left-sided breast cancer underwent CT scans during breathing maneuvers including free breathing (FB), deep inspiration breath-hold (DIBH), and end inspiration breath-hold (EIBH). The RPM system was used to monitor respiratory motion, and the in-house self respiration monitoring (SRM) system was used for visual feedback. For each scan, treatment plans were generated and dosimetric parameters from DIBH and EIBH plans were compared to those of FB plans. Results All patients completed CT scans with different breathing maneuvers. When compared with FB plans, DIBH plans demonstrated significant reductions in irradiated heart volume and the heart V25, with the relative reduction of 71% and 70%, respectively (p < 0.001). EIBH plans also resulted in significantly smaller irradiated heart volume and lower heart V25 than FB plans, with the relative reduction of 39% and 37%, respectively (p = 0.002). Despite of significant expansion of lung volume using inspiration breath-hold, there were no significant differences in left lung V25 among the three plans. Conclusion In comparison with FB, both DIBH and EIBH plans demonstrated a significant reduction of radiation dose to the heart. In the training course, SRM system was useful and effective in terms of positional reproducibility and patient compliance. PMID:25061577

Sung, KiHoon; Lee, Seung Heon; Ahn, So Hyun; Lee, Seok Ho; Choi, Jinho

2014-01-01

88

Two-domain mechanics of a spherical, single chamber heart with applications to specific cardiac pathologies.  

PubMed

Continuum approximations of tissue consider responses averaged over many cells in a region. This simplified approach allows consideration of macroscopic effects, such as deformation or action potential propagation. A bidomain (sometimes known as biphasic) approach retains the macroscopic character of a continuum approximation while allowing one to consider microscopic effects; novel behavior arising from interactions between the intracellular and extracellular spaces can also be noted. I consider a spherical, single chamber heart with the new mechanical bidomain model in four separate pathologies: hypertension, hypovolemic hypotension, and hypertrophic and dilational cardiomyopathies. Analytic solutions of intracellular and extracellular displacements and hydrostatic pressures are presented; the distributions describe elastic deformation and hydrostatic fluid pressure buildup of the extracellular collagen matrix and the intracellular muscle under simplified spherical geometry. Potential applications, such as stretch activated membrane channels, are also noted. PMID:23875126

Puwal, Steffan

2013-12-01

89

Baseline tissue Doppler imaging-derived echocardiographic parameters and left ventricle reverse remodelling following cardiac resynchronization therapy introduction  

PubMed Central

Introduction The aim of the study was to assess the relation of baseline mechanical dyssynchrony with the left ventricular end-systolic volume (LVESV) decrease following cardiac resynchronization (CRT) therapy introduction. Material and methods Sixty consecutive patients (aged 66.3 ± 8.7 years; 57 men) with chronic heart failure (71.7% of ischaemic and 28.3% of non-ischaemic origin) and current indications for CRT were assessed before and 3 months after biventricular heart stimulator implantation. Longitudinal movements of twelve segments of the left ventricle (LV) (6 basal and 6 midlevel) and two segments of the right ventricle (RV) were analysed using tissue Doppler imaging (TDI) techniques with time from onset of Q wave in ECG to peak systolic velocity in colour-coded TDI (TTDI), time to peak strain (Tstrain) and time to peak strain rate (Tstrain rate). Minimal and maximal time differences within LV and between LV and RV walls were calculated. Results In the study group LVEF and 6-min walk test distance increased, while NYHA class, NT-proBNP level, left ventricular end-diastolic volume and LVESV decreased. Significant correlations between the magnitude of LVESV reduction with maximal time differences between Tstrain of 12 LV segments (r=0.34, p = 0.017) and time differences between TTDI basal LV-RV segments (r = –0.29, p=0.041) were found. Conclusions Only a few TDI-derived parameters such as maximal time differences between Tstrain of 12 LV segments and TTDI difference of LV-RV basal segments can be useful to predict the magnitude of left ventricle reverse remodelling after CRT introduction. PMID:22291826

Wili?ski, Jerzy; Czarnecka, Danuta; Wojciechowska, Wiktoria; Kloch-Bade?ek, Ma?gorzata; Jastrz?bski, Marek; Bacior, Bogumi?a; Sondej, Tomasz; Kusiak, Aleksander

2011-01-01

90

Effect of sublingual nitroglycerin on cardiac performance in patients with coronary artery disease and non-dyskinetic left ventricular contraction.  

PubMed Central

In 8 patients with coronary artery disease and symmetrical left ventricular contraction, an echocardiographic study of left ventricular function was performed before and 3 minutes after the administration of 0-6 mg nitroglycerin sublingually. The left ventricular end-diastolic diameter decreased from 5-2 +/- 0-2 to 4-9 +/- 0-2 cm (P less than 0-05) and the end-systolic diameter from 4-2 +/- 0-2 to 3-7 +/- 0-2 cm (P less than 0-001). The estimated stroke volume did not change significantly, while the cardiac output increased, 5-8 +/- 0-6 to 7-7 +/- 0-6 l min-1 (P less than 0-001) and the heart rate increased from 72 +/- 5 to 90 +/- 6 (P less than 0-001). The mean arterial blood pressure decreased from 105 +/- 4 to 88 +/- 3 mmHg (P less than 0-001). The ejection fraction increased from 53 +/- 3 per cent to 65 +/- 6 per cent (P less than 0-001) and the mean velocity of circumferential fibre shortening (VCF) from 0-81 +/- 0-05 to 1-15 +/- 0-10 circumferences per second (P less than 0-001). The estimated midsystolic midwall stress decreased from 155 +/- 14 g cm-2 to 102 +/- 12 g cm-2 after mitroglycerin (P less than 0-001). The administration of nitroglycerin was associated with a significant decrease in left ventricular preload and afterload. A vasodilating effect is suggested by the fall in peripheral resistance. The overall improvement in ejection fraction and VCF may not reflect a true increase contractility, because of the concomitant fall in wall stress. Images PMID:827302

Hardarson, T; Wright, K E

1976-01-01

91

Congenital giant cardiac tumor with severe left-ventricular inflow and outflow obstruction and arrhythmia treated with pulmonary artery banding and long-term amiodarone infusion  

PubMed Central

We report a congenital giant cardiac tumor that occupied the majority of left ventricular cavity with severe left ventricular inflow and outflow obstruction. The hemodynamics were similar to univentricular physiology. He was treated with prostaglandins and bilateral pulmonary artery banding. He had frequent supraventricular tachycardia associated with ventricular pre-excitation that was controlled by long-term administration of intravenous amiodarone. The patient died due to sepsis after 3 months. PMID:22529609

Takeuchi, Daiji; Hiramatsu, Takeshi; Nakanishi, Toshio

2012-01-01

92

Cardiac CD47 Drives Left Ventricular Heart Failure Through Ca2+?CaMKII?Regulated Induction of HDAC3  

PubMed Central

Background Left ventricular heart failure (LVHF) remains progressive and fatal and is a formidable health problem because ever?larger numbers of people are diagnosed with this disease. Therapeutics, while relieving symptoms and extending life in some cases, cannot resolve this process and transplant remains the option of last resort for many. Our team has described a widely expressed cell surface receptor (CD47) that is activated by its high?affinity secreted ligand, thrombospondin 1 (TSP1), in acute injury and chronic disease; however, a role for activated CD47 in LVHF has not previously been proposed. Methods and Results In experimental LVHF TSP1?CD47 signaling is increased concurrent with up?regulation of cardiac histone deacetylase 3 (HDAC3). Mice mutated to lack CD47 displayed protection from transverse aortic constriction (TAC)?driven LVHF with enhanced cardiac function, decreased cellular hypertrophy and fibrosis, decreased maladaptive autophagy, and decreased expression of HDAC3. In cell culture, treatment of cardiac myocyte CD47 with a TSP1?derived peptide, which binds and activates CD47, increased HDAC3 expression and myocyte hypertrophy in a Ca2+/calmodulin protein kinase II (CaMKII)?dependent manner. Conversely, antibody blocking of CD47 activation, or pharmacologic inhibition of CaMKII, suppressed HDAC3 expression, decreased myocyte hypertrophy, and mitigated established LVHF. Downstream gene suppression of HDAC3 mimicked the protective effects of CD47 blockade and decreased hypertrophy in myocytes and mitigated LVHF in animals. Conclusions These data identify a proximate role for the TSP1?CD47 axis in promoting LVHF by CaKMII?mediated up?regulation of HDAC3 and suggest novel therapeutic opportunities. PMID:24922625

Sharifi?Sanjani, Maryam; Shoushtari, Ali Hakim; Quiroz, Marisol; Baust, Jeffrey; Sestito, Samuel F.; Mosher, Mackenzie; Ross, Mark; McTiernan, Charles F.; St. Croix, Claudette M.; Bilonick, Richard A.; Champion, Hunter C.; Isenberg, Jeffrey S.

2014-01-01

93

Automatic computation of left ventricular volume changes over a cardiac cycle from echocardiography images by nonlinear dimensionality reduction.  

PubMed

Curve of left ventricular (LV) volume changes throughout the cardiac cycle is a fundamental parameter for clinical evaluation of various cardiovascular diseases. Currently, this evaluation is often performed manually which is tedious and time consuming and suffers from significant interobserver and intraobserver variability. This paper introduces a new automatic method, based on nonlinear dimensionality reduction (NLDR) for extracting the curve of the LV volume changes over a cardiac cycle from two-dimensional (2-D) echocardiography images. Isometric feature mapping (Isomap) is one of the most popular NLDR algorithms. In this study, a modified version of Isomap algorithm, where image to image distance metric is computed using nonrigid registration, is applied on 2-D echocardiography images of one cycle of heart. Using this approach, the nonlinear information of these images is embedded in a 2-D manifold and each image is characterized by a symbol on the constructed manifold. This new representation visualizes the relationship between these images based on LV volume changes and allows extracting the curve of the LV volume changes automatically. Our method in comparison to the traditional segmentation algorithms does not need any LV myocardial segmentation and tracking, particularly difficult in the echocardiography images. Moreover, a large data set under various diseases for training is not required. The results obtained by our method are quantitatively evaluated to those obtained manually by the highly experienced echocardiographer on ten healthy volunteers and six patients which depict the usefulness of the presented method. PMID:25059548

Alizadeh Sani, Zahra; Shalbaf, Ahmad; Behnam, Hamid; Shalbaf, Reza

2015-02-01

94

The effect of disease on human cardiac protein expression profiles in paired samples from right and left ventricles  

PubMed Central

Background Cardiac diseases (e.g. coronary and valve) are associated with ventricular cellular remodeling. However, ventricular biopsies from left and right ventricles from patients with different pathologies are rare and thus little is known about disease-induced cellular remodeling in both sides of the heart and between different diseases. We hypothesized that the protein expression profiles between right and left ventricles of patients with aortic valve stenosis (AVS) and patients with coronary artery disease (CAD) are different and that the protein profile is different between the two diseases. Left and right ventricular biopsies were collected from patients with either CAD or AVS. The biopsies were processed for proteomic analysis using isobaric tandem mass tagging and analyzed by reverse phase nano-LC-MS/MS. Western blot for selected proteins showed strong correlation with proteomic analysis. Results Proteomic analysis between ventricles of the same disease (intra-disease) and between ventricles of different diseases (inter-disease) identified more than 500 proteins detected in all relevant ventricular biopsies. Comparison between ventricles and disease state was focused on proteins with relatively high fold (±1.2 fold difference) and significant (P?left and right ventricles were largely structural for AVS patients and largely signaling/metabolism for CAD. Proteins commonly associated with hypertrophy were also different in the AVS group but with lower fold difference. Inter-disease differences between left ventricles of AVS and CAD were detected in 9 proteins. However, inter-disease differences between the right ventricles of CAD and AVS patients were associated with differences in 73 proteins. The majority of proteins which had a significant difference in one ventricle compared to the other pathology also had a similar trend in the adjacent ventricle. Conclusions This work demonstrates for the first time that left and right ventricles have a different proteome and that the difference is dependent on the type of disease. Inter-disease differential expression was more prominent for right ventricles. The finding that a protein change in one ventricle was often associated with a similar trend in the adjacent ventricle for a large number of proteins suggests cross-talk proteome remodeling between adjacent ventricles. PMID:25249829

2014-01-01

95

Chronic beta-adrenoreceptor activation increases cardiac cavity size through chamber remodeling and not via modifications in myocardial material properties.  

PubMed

Chronic beta-adrenoreceptor (beta-AR) activation increases left ventricular (LV) cavity size by promoting a rightward shift in LV diastolic pressure-volume (P-V) relations in association with increases in low-tensile strength myocardial (non-cross-linked) collagen concentrations. Because diastolic P-V relations are determined by chamber remodeling as well as by myocardial material properties (indexed by myocardial stiffness), both of which are associated with modifications in myocardial collagen cross-linking, we evaluated whether chamber remodeling or alterations in myocardial material properties govern beta-AR-mediated modifications in diastolic P-V relations. The effects of chronic administration of isoproterenol (Iso; 0.04 mg.kg(-1).day(-1) from 12 to 19 mo of age) to spontaneously hypertensive rats (SHRs) on LV cavity dimensions, LV diastolic P-V relations, myocardial collagen characteristics, myocardial stiffness constants [e.g., the slope of the LV diastolic stress-strain relation (k)], and LV chamber and myocardial systolic function were assessed. SHRs at 19 mo of age had normal LV diastolic P-V relations, marked myocardial fibrosis (using a pathological score), increased myocardial cross-linked (insoluble to cyanogen bromide digestion) type I and type III collagen concentrations, and enhanced myocardial k values. Iso administration to SHRs resulted in enlarged LV cavity dimensions mediated by a rightward shift in LV diastolic P-V relations, increased volume intercept of the LV diastolic P-V relation, decreased LV relative wall thickness despite a tendency to augment LV hypertrophy, and increased non-cross-linked type I and type III myocardial collagen concentrations. Iso administration resulted in reduced pump function without modification of intrinsic myocardial systolic function. However, despite increasing myocardial non-cross-linked concentrations, Iso failed to alter myocardial k in SHRs. These results suggest that beta-AR-mediated rightward shifts in LV diastolic P-V relations, which induce decreased pump function, are mediated by chamber remodeling but not by modifications in myocardial material properties. PMID:15319203

Gibbs, Mark; Veliotes, Demetri G A; Anamourlis, Christopher; Badenhorst, Danelle; Osadchii, Oleg; Norton, Gavin R; Woodiwiss, Angela J

2004-12-01

96

High Prevalence of Cardiac Parvovirus B19 Infection in Patients With Isolated Left Ventricular Diastolic Dysfunction  

Microsoft Academic Search

Background—The etiology of left ventricular (LV) isolated diastolic dysfunction often remains unclear. In the present study, we report a strong association between parvovirus B19 (PVB19) genomes and isolated LV diastolic dysfunction. Methods and Results—In 70 patients (meanSD age, 4311 years) admitted with exertional dyspnea and\\/or reduced exercise tolerance despite preserved LV systolic contractility (ejection fraction68%), isolated diastolic dysfunction was clinically

C. Tschöpe; C.-T. Bock; M. Kasner; M. Noutsias; D. Westermann; P.-L. Schwimmbeck; M. Pauschinger; W.-C. Poller; U. Kühl; R. Kandolf; H.-P. Schultheiss

2010-01-01

97

Right aortic arch with isolation of the left innominate artery in a case of double chamber right ventricle and ventricular septal defect  

PubMed Central

Herein, we report an unusual case of right aortic arch with isolation of the left innominate artery in a case of double chamber right ventricle with ventricular septal defect. The blood supply to the innominate artery was by a collateral arising from the descending aorta. The embryological development of this anomaly can be explained by the hypothetical double aortic arch model proposed by Edwards with interruption of the arch at two levels. PMID:24987265

Mangukia, Chirantan; Sethi, Sonali; Agarwal, Saket; Mishra, Smita; Satsangi, Deepak kumar

2014-01-01

98

Relation of Natriuretic Peptides and Midregional Proadrenomedullin to Cardiac Chamber Volumes by Computed Tomography in Patients without Heart Failure: From the ROMICAT Trial  

PubMed Central

BACKGROUND Stress myocyte biomarkers are used prognostically in patients with cardiovascular disease. We examined associations between amino-terminal pro–B-type natriuretic peptide (NT-proBNP), midregional pro–A-type natriuretic peptide (MR-proANP), and midregional proadrenomedullin (MR-proADM) concentrations and cardiac chamber volumes in chest pain patients without heart failure by use of computed tomography (CT). METHODS At the time of 64-slice CT scan, we acquired plasma and serum samples for these biomarkers from 346 patients [mean (SD) age 53 (12) years, 65% men]. Left atrial volume (LAV) and left ventricular volumes at end-diastole (LVEDV) and end-systole (LVESV) were measured and indexed to body surface area (LAVI, LVEDI, LVESI). RESULTS Concentrations of both natriuretic peptides were correlated with LAV and LAVI (r=0.19–0.32, all P ? 0.0005) and MR-proADM with LV volumes and indices (r=?0.14 to ?0.21, all P ? 0.01). NT-proBNP and MR-proANP concentrations were higher in the top quartiles of patients than the lowest quartiles using LAV and LAVI, whereas MR-proADM concentrations were lower in the top quartiles of LV measures. In adjusted analyses, patients had 2- to 4-fold increased risk of LA enlargement for every incremental increase in log10NT-proBNP [LAV odds ratio (OR) 2.4, P = 0.03; LAVI OR 4.0, P = 0.003] and 10- to 13-fold increased risk of LA enlargement for every incremental increase in log10MR-proANP (LAV OR 10.7, P = 0.009; LAVI OR 13.1, P = 0.004). CONCLUSIONS In patients without heart failure, both NT-proBNP and MR-proANP concentrations are independently associated with LA enlargement, whereas MR-proADM concentrations are correlated with LV volumes. This may partially explain the well-recognized value of natriuretic peptides for use in risk stratification. PMID:20185624

Truong, Quynh A.; Siegel, Emily; Karakas, Mahir; Januzzi, James L.; Bamberg, Fabian; Mahabadi, Amir A.; Dasdemir, Selcuk; Brady, Thomas J.; Bergmann, Andreas; Kunde, Jan; Nagurney, John T.; Hoffmann, Udo; Koenig, Wolfgang

2010-01-01

99

Cardiac MRI and CT: Differentiation of Normal Ostium and Intraseptal Course From Slitlike Ostium and Interarterial Course in Anomalous Left Coronary Artery in Children.  

PubMed

OBJECTIVE. Anomalous left coronary artery from the inappropriate aortic sinus with intraseptal course is generally benign but can be confused on imaging studies with the potentially lethal interarterial, intramural anomalous left coronary artery. The purpose of this study was to assess normal ostial morphologic features and intraseptal course using cardiac MRI and CT in pediatric patients with intraseptal anomalous left coronary artery. MATERIALS AND METHODS. A retrospective review was conducted of the medical records of 14 children with the diagnosis of intraseptal anomalous left coronary artery between November 2009 and March 2013. Coronary artery origin and course were evaluated with cardiac MRI or CT, and 3D assessment of coronary ostial morphologic features was performed with virtual angioscopy. RESULTS. The patient ages ranged from 5 to 18 years at diagnosis; 10 (71.4%) were boys. The right and left coronary origins were the right sinus of Valsalva as a common origin (n = 9) or a single coronary artery (n = 5). Anomalous intraseptal left main coronary was found in 13 patients, and one patient had anomalous left anterior descending with retroaortic circumflex coronary artery. Anomalous coronary ostia were round and without stenosis in all studies. The anomalous vessel was identified with echocardiography, but the anomalous left coronary artery was not delineated, and a normal ostium was not adequately portrayed in any instance. CONCLUSION. By use of cardiac MRI and CT, the anomalous course of round coronary ostia was confirmed and visualized in a pediatric cohort with intraseptal anomalous left coronary artery. The data provide the basis for understanding the benign clinical course and showing that surgery is unnecessary for this coronary anomaly. PMID:25539262

Brothers, Julie A; Whitehead, Kevin K; Keller, Marc S; Fogel, Mark A; Paridon, Stephen M; Weinberg, Paul M; Harris, Matthew A

2015-01-01

100

Comparison of Echocardiographic and Cardiac Magnetic Resonance Imaging in Hypertrophic Cardiomyopathy Sarcomere Mutation Carriers Without Left Ventricular Hypertrophy  

PubMed Central

Background Left ventricular hypertrophy (LVH) typically manifests during or after adolescence in sarcomere mutation carriers at risk for developing hypertrophic cardiomyopathy. Guidelines recommend serial imaging of mutation carriers without LVH (G+/LVH?) to monitor for phenotypic evolution, but the optimal strategy is undefined. Compared with echocardiography (echo), cardiac MRI (CMR) offers improved endocardial visualization and potential to assess scar. However, the incremental advantage offered by CMR for early diagnosis of hypertrophic cardiomyopathy is unclear. Therefore, we systematically compared echo and CMR in G+/LVH? subjects. Methods and Results A total of 40 sarcomere mutation carriers with normal echo wall thickness (<12 mm or z score <2.5 in children) underwent concurrent CMR. Mean age was 21.7±11.1 years, 55% were female. If left ventricular wall thickness seemed nonuniform, the size and location of relatively thickened segments were noted. Late gadolinium enhancement was assessed with CMR. Diagnostic agreement between echo and CMR was good (90%), although CMR measurements of left ventricular wall thickness were ?19% lower than echo. Four subjects had mild hypertrophy (12.6–14 mm; ?2 segments) appreciated by CMR but not echo. No subjects had late gadolinium enhancement. During median 35-month follow-up, 2 subjects developed overt hypertrophic cardiomyopathy, including 1 with mild LVH by CMR at baseline. Conclusions Echo is unlikely to miss substantial LVH; however, CMR identified mild hypertrophy in ?10% of mutation carriers with normal echo wall thickness. CMR may be a useful adjunct in hypertrophic cardiomyopathy family screening, particularly in higher risk situations, or if echocardiographic images are suboptimal or suggest borderline LVH. PMID:23690394

Valente, Anne Marie; Lakdawala, Neal K.; Powell, Andrew J.; Evans, Sarah P.; Cirino, Allison L.; Orav, E. John.; MacRae, Calum A.; Colan, Steven D.; Ho, Carolyn Y.

2014-01-01

101

Correlation of heart rate variability with cardiac functional and metabolic variables in cyclists with training induced left ventricular hypertrophy  

PubMed Central

OBJECTIVE—To examine the correlation between heart rate variability and left ventricular mass in cyclists with an athlete's heart.?METHODS—Left ventricular mass and diastolic function were determined at rest and myocardial high energy phosphates were quantified at rest and during atropine-dobutamine stress in 12 male cyclists and 10 control subjects, using magnetic resonance techniques. Ambulatory 24 hour ECG recordings were obtained, and time and frequency domain heart rate variability indices were computed.?RESULTS—In the cyclists, the mean of all RR intervals between normal beats (meanNN), the SD of the RR intervals, and their coefficient of variation were significantly greater than in control subjects (p < 0.01, p < 0.01, and p < 0.05, respectively). For cyclists and control subjects, only meanNN correlated with left ventricular mass (r = 0.48, p = 0.038). The heart rate variability indices that correlated with functional or metabolic variables were: meanNN v E/A peak (the ratio of peak early and peak atrial filling rate) (r = 0.48, p = 0.039); the root mean square of successive differences in RR intervals among successive normal beats v E/A area (ratio of peak early and peak atrial filling volume) (r = 0.48, p = 0.040); percentage of successive RR intervals differing by more than 50 ms v the phosphocreatine to ATP ratio at rest (r = 0.54, p = 0.017); and the SD of the average RR intervals during all five minute periods v the phosphocreatine to ATP ratio during stress (r = 0.60, p = 0.007).?CONCLUSIONS—Highly trained cyclists have increased heart rate variability indices, reflecting increased cardiac vagal control compared with control subjects. Left ventricular mass has no major influence on heart rate variability, but heart rate variability is significantly correlated with high energy phosphate metabolism and diastolic function.???Keywords: heart rate variability; left ventricular mass; hypertrophy; athlete's heart PMID:10336920

Pluim, B; Swenne, C; Zwinderman, A; Maan, A; van der Laarse, A; Doornbos, J; Van der Wall, E E

1999-01-01

102

microRNA-21 promotes cardiac fibrosis and development of heart failure with preserved left ventricular ejection fraction by up-regulating Bcl-2  

PubMed Central

The morbidity and mortality of heart failure with preserved left ventricular ejection fraction (HFpEF) were similar to those of systolic heart failure, but the pathogenesis of HFpEF remains poorly understood. It was demonstrated that, in systolic heart failure, microRNA-21 (miR-21) could inhibit the apoptosis of cardiac fibroblasts, leading to cardiac hypertrophy and myocardial fibrosis, but the role of miR-21 in HFpEF remains unknown. By employing cell culture technique, rat myocardiocytes and cardiac fibroblasts were obtained. The expression of miR-21 in the two cell types under different conditions was compared and we found that the miR-21 expression was significantly higher in cardiac fibroblasts than in myocardiocytes. We established a rat HFpEF model and harvested the tissues of cardiac apex for pathological examination, Northern blotting and so forth. We found that miR-21 expression was significantly higher in model rats than in sham-operated rats, and the model rats developed the cardiac atrophy and cardiac fibrosis. After injection of miR-21 antagonist, the the cardiac atrophy and cardiac fibrosis were conspicuously ameliorated. Both in vivo and in vitro, inhibition of miR-21 expression resulted in reduced Bcl-2 expression while over-expression of miR-21 led to elevation of Bcl-2 expression. Our study suggested that miR-21 promoted the development of HFpEF by up-regulating the expression of anti-apoptotic gene Bcl-2 and thereby suppressing the apoptosis of cardiac fibrosis. PMID:24551276

Dong, Shuguang; Ma, Wenhan; Hao, Bohan; Hu, Fen; Yan, Lianhua; Yan, Xiaofei; Wang, Ya; Chen, Zhijian; Wang, Zhaohui

2014-01-01

103

Optimal use of left ventriculography at the time of cardiac catheterization: A consensus statement from the society for cardiovascular angiography and interventions.  

PubMed

The rationale to perform left ventriculography at the time of cardiac catheterization has been little studied. The technique and frequency of use of left ventriculography vary by geographic regions, institutions, and individuals. Despite the recent publication of guidelines and appropriate use criteria for coronary angiography, revascularization, and noninvasive imaging, to date there have been no specific guidelines on the performance of left ventriculography. When left ventriculography is performed, proper technique must be used to generate high quality data which can direct patient management. The decision to perform left ventriculography in place of, or in addition to, other forms of ventricular assessment should be made taking into account the clinical context and the type of information each study provides. This paper attempts to show the role of left ventriculography at the time of coronary angiography or left heart catheterization. The recommendations in this document are not formal guidelines but are based on the consensus of this writing group. These recommendations should be tested through clinical research studies. Until such studies are performed, the writing group believes that adoption of these recommendations will lead to a more standardized application of ventriculography and improve the quality of care provided to cardiac patients. © 2014 Wiley Periodicals, Inc. PMID:25370476

Gigliotti, Osvaldo S; Babb, Joseph D; Dieter, Robert S; Feldman, Dmitriy N; Islam, Ashequl M; Marmagkiolis, Konstantinos; Moore, Phillip; Sorajja, Paul; Blankenship, James C

2014-11-01

104

Successful myocardial revascularization and neurologic recovery in a patient with prolonged refractory cardiac arrest and a chronically occluded left internal carotid artery.  

PubMed Central

Heretofore, the longest successfully treated cardiac arrest reported in the literature, secondary to myocardial ischemia, was one that required 45 minutes of cardiopulmonary resuscitation before coronary bypass surgery. We present a unique case of successful resuscitation after a cardiac arrest secondary to myocardial ischemia. The arrest lasted 78 minutes (30 minutes of closed cardiac massage and 48 minutes of open cardiac massage). As soon as a perfusionist was available, cardiopulmonary bypass was initiated. After completion of the distal anastomosis and upon removal of the aortic cross clamp, the patient spontaneously recovered sinus rhythm for the 1st time since her cardiac arrest 2 hours and 10 minutes earlier. This 70-year-old woman, with a history of chronic occlusion of the left internal carotid artery, recovered fully, without evidence of neurologic or myocardial insult. We believe that vigorous closed and open cardiac massage, followed by cardiopulmonary bypass and the correction of myocardial ischemia, enabled this patient to survive a prolonged refractory cardiac arrest. PMID:7580369

Tovar, E A; Del Campo, C; Landa, D W; Borsari, A

1995-01-01

105

Dyspnoea of cardiac origin in 67 year old men: (2). Relation to diastolic left ventricular function and mass. The study of men born in 1913.  

PubMed Central

The relation of cardiac dyspnoea to diastolic left ventricular dysfunction was examined in a sample of 67 year old men from the general population of Gothenburg, Sweden. Forty two men with cardiac dyspnoea and 45 controls were selected from the screened cohort of 644 men. M mode echocardiography, apexcardiography, and phonocardiography were used to evaluate heart sounds, diastolic time intervals, aortic root motion (atrial emptying index); peak rate of change in left ventricular dimension, left atrial and ventricular size; and left ventricular mass. There was a significant relation between dyspnoea grade and left ventricular mass and posterior wall thickness. Dyspnoea grade also correlated significantly with the amplitude of the rapid filling wave and the third heart sound, atrial emptying index and left atrial size, the pulmonary component of the second heart sound, and the dimension of the right ventricle. In mild to moderate dyspnoea fractional shortening was normal, but posterior wall thickness and left atrial dimension were increased. The time from the second heart sound to the O point of the apexcardiogram, adjusted for heart rate, was significantly prolonged in mild to moderate dyspnoea, but not in severe dyspnoea. There was a significant decrease of rate adjusted isovolumic relaxation time, probably secondary to altered loading conditions, in severe dyspnoea, but not in mild to moderate dyspnoea. When the effect of systolic function was excluded multivariate analyses showed that the relation between dyspnoea grade and left atrial dimension persisted. The finding that diastolic abnormalities of the heart contributed to the generation of cardiac dyspnoea may have implications for treatment. PMID:2965595

Caidahl, K; Eriksson, H; Hartford, M; Wikstrand, J; Wallentin, I; Arvidsson, A; Svärdsudd, K

1988-01-01

106

Dipyridamole-thallium tests are predictive of severe cardiac arrhythmias in patients with left ventricular hypertrophy  

SciTech Connect

In a population of patients with chronic renal failure (CRF) and a high prevalence of left ventricular hypertrophy (LVH) undergoing chronic hemodialysis, the authors investigated the association between the results of dipyridamole-thallium tests (DTTs) and the occurrence of ventricular arrhythmias. They observed a positive significant association between positive DTTs and the occurrence of severe forms of ventricular arrhythmias. A significant association was also observed between the presence of severe LVH and the occurrence of severe ventricular arrhythmias. However, no association was found between the presence of LVH and the positivity of the DTT. As most of their patients with positive DTTs had unimpaired coronary circulations, they conclude that positive DTTs, although falsely indicative of impaired myocardial blood supply, does have an important clinical relevance, indicating increased risk of morbidity (and, possibly, mortality) due to ventricular arrhythmias in a population of CRF patients submitted to chronic renal function replacement program.

Saragoca, M.A.; Canziani, M.E.; Gil, M.A.; Castiglioni, M.L.; Cassiolato, J.L.; Barbieri, A.; Lima, V.C.; Draibe, S.A.; Martinez, E.E. (Cardiology Division, Escola Paulista de Medicina, Sao Paulo (Brazil))

1991-01-01

107

Neuraxial Modulation for Refractory Ventricular Arrhythmias: Value of Thoracic Epidural Anesthesia and Surgical Left Cardiac Sympathetic Denervation  

PubMed Central

Background Reducing sympathetic output to the heart from the neuraxis can protect against ventricular arrhythmias. The purpose of this study was to assess the value of thoracic epidural anesthesia (TEA) and left cardiac sympathetic denervation (LCSD) in the management of ventricular arrhythmias in patients with structural heart disease (SHD). Methods and Results Clinical data of 14 patients (age 25-75 years, 54.2±16.6 yrs,(mean±SD) 13 males) who underwent TEA, LCSD, or both, to control ventricular tachycardia (VT) refractory to medical therapy and catheter ablation were reviewed.12 patients were in VT storm and 2 patients experienced recurrent VT despite maximal medical therapy and catheter ablation procedures. Total number of therapies per patient prior to either procedure ranged from 5 to 202 (median of 24, 25th and 75th percentile of 5 and 56). Eight patients underwent TEA and 9 patients underwent LCSD (3 patients had both procedures). No major procedural complications occurred. After initiation of TEA, 6 patients had a large (?80%) decrease in VT burden. Post LCSD, 3 patients had no further VT, 2 patients had recurrent VT which either resolved within 24 hours or responded to catheter ablation, and 4 patients continued to have recurrent VT. Nine out of 14 patients survived to hospital discharge (1 TEA alone, 3 TEA/LCSD combined, 4 LCSD alone), one of whom underwent an urgent cardiac transplantation (TEA alone). Conclusion Initiation of TEA and LCSD in patients with refractory VT was associated with a subsequent decrease in arrhythmia burden in 6 out of 8 (75%- CI 51% to 91%) and 5 out of 9 (56%- CI 34% to 75%) patients, respectively. These data suggest that TEA and LCSD may be effective additions to the management of refractory ventricular arrhythmias in SHD when other treatment modalities have failed and/or may serve as a bridge to more definitive therapy. PMID:20479150

Bourke, Tara; Vaseghi, Marmar; Michowitz, Yoav; Sankhla, Vineet; Shah, Mandar; Swapna, Nalla; Boyle, Noel G.; Mahajan, Aman; Narasimhan, Calambur; Lokhandwala, Yash; Shivkumar, Kalyanam

2010-01-01

108

Quantitative modeling of the accuracy in registering preoperative patient-specific anatomic models into left atrial cardiac ablation procedures  

SciTech Connect

Purpose: In cardiac ablation therapy, accurate anatomic guidance is necessary to create effective tissue lesions for elimination of left atrial fibrillation. While fluoroscopy, ultrasound, and electroanatomic maps are important guidance tools, they lack information regarding detailed patient anatomy which can be obtained from high resolution imaging techniques. For this reason, there has been significant effort in incorporating detailed, patient-specific models generated from preoperative imaging datasets into the procedure. Both clinical and animal studies have investigated registration and targeting accuracy when using preoperative models; however, the effect of various error sources on registration accuracy has not been quantitatively evaluated. Methods: Data from phantom, canine, and patient studies are used to model and evaluate registration accuracy. In the phantom studies, data are collected using a magnetically tracked catheter on a static phantom model. Monte Carlo simulation studies were run to evaluate both baseline errors as well as the effect of different sources of error that would be present in a dynamicin vivo setting. Error is simulated by varying the variance parameters on the landmark fiducial, physical target, and surface point locations in the phantom simulation studies. In vivo validation studies were undertaken in six canines in which metal clips were placed in the left atrium to serve as ground truth points. A small clinical evaluation was completed in three patients. Landmark-based and combined landmark and surface-based registration algorithms were evaluated in all studies. In the phantom and canine studies, both target registration error and point-to-surface error are used to assess accuracy. In the patient studies, no ground truth is available and registration accuracy is quantified using point-to-surface error only. Results: The phantom simulation studies demonstrated that combined landmark and surface-based registration improved landmark-only registration provided the noise in the surface points is not excessively high. Increased variability on the landmark fiducials resulted in increased registration errors; however, refinement of the initial landmark registration by the surface-based algorithm can compensate for small initial misalignments. The surface-based registration algorithm is quite robust to noise on the surface points and continues to improve landmark registration even at high levels of noise on the surface points. Both the canine and patient studies also demonstrate that combined landmark and surface registration has lower errors than landmark registration alone. Conclusions: In this work, we describe a model for evaluating the impact of noise variability on the input parameters of a registration algorithm in the context of cardiac ablation therapy. The model can be used to predict both registration error as well as assess which inputs have the largest effect on registration accuracy.

Rettmann, Maryam E., E-mail: rettmann.maryam@mayo.edu; Holmes, David R.; Camp, Jon J.; Cameron, Bruce M.; Robb, Richard A. [Biomedical Imaging Resource, Mayo Clinic College of Medicine, Rochester, Minnesota 55905 (United States)] [Biomedical Imaging Resource, Mayo Clinic College of Medicine, Rochester, Minnesota 55905 (United States); Kwartowitz, David M. [Department of Bioengineering, Clemson University, Clemson, South Carolina 29634 (United States)] [Department of Bioengineering, Clemson University, Clemson, South Carolina 29634 (United States); Gunawan, Mia [Department of Biochemistry and Molecular and Cellular Biology, Georgetown University, Washington D.C. 20057 (United States)] [Department of Biochemistry and Molecular and Cellular Biology, Georgetown University, Washington D.C. 20057 (United States); Johnson, Susan B.; Packer, Douglas L. [Division of Cardiovascular Diseases, Mayo Clinic, Rochester, Minnesota 55905 (United States)] [Division of Cardiovascular Diseases, Mayo Clinic, Rochester, Minnesota 55905 (United States); Dalegrave, Charles [Clinical Cardiac Electrophysiology, Cardiology Division Hospital Sao Paulo, Federal University of Sao Paulo, 04024-002 Brazil (Brazil)] [Clinical Cardiac Electrophysiology, Cardiology Division Hospital Sao Paulo, Federal University of Sao Paulo, 04024-002 Brazil (Brazil); Kolasa, Mark W. [David Grant Medical Center, Fairfield, California 94535 (United States)] [David Grant Medical Center, Fairfield, California 94535 (United States)

2014-02-15

109

QRS pattern and improvement in right and left ventricular function after cardiac resynchronization therapy: a radionuclide study  

PubMed Central

Background Predicting response to cardiac resynchronization therapy (CRT) remains a challenge. We evaluated the role of baseline QRS pattern to predict response in terms of improvement in biventricular ejection fraction (EF). Methods Consecutive patients (pts) undergoing CRT implantation underwent radionuclide angiography at baseline and at mid-term follow-up. The relationship between baseline QRS pattern and mechanical dyssynchrony using phase analysis was evaluated. Changes in left and right ventricular EF (LVEF and RVEF) were analyzed with regard to baseline QRS pattern. Results We enrolled 56 pts, 32 with left bundle branch block (LBBB), 4 with right bundle branch block (RBBB) and 20 with non-specific intraventricular conduction disturbance (IVCD). A total of 48 pts completed follow-up. LBBB pts had significantly greater improvement in LVEF compared to RBBB or non-specific IVCD pts (+9.6 ± 10.9% vs. +2.6 ± 7.6%, p = 0.003). Response (defined as ? 5% increase in LVEF) was observed in 68% of LBBB vs. 24% of non-specific IVCD pts (p = 0.006). None of the RBBB pts were responders. RVEF was significantly improved in LBBB (+5.0 ± 9.0%, p = 0.007), but not in non-specific IVCD and RBBB pts (+0.4 ± 5.8%, p = 0.76). At multivariate analysis, LBBB was the only predictor of LVEF response (OR, 7.45; 95% CI 1.80-30.94; p = 0.006), but not QRS duration or extent of mechanical dyssynchrony. Conclusions Presence of a LBBB is a marker of a positive response to CRT in terms of biventricular improvement. Pts with non-LBBB pattern show significantly less benefit from CRT than those with LBBB. PMID:22494365

2012-01-01

110

B-type natriuretic peptide release and left ventricular filling pressure assessed by echocardiographic study after subarachnoid hemorrhage: a prospective study in non-cardiac patients  

Microsoft Academic Search

Introduction  Serum B-type natriuretic peptide (BNP) is frequently elevated after subarachnoid hemorrhage (SAH), but whether this high BNP\\u000a level is related to transient elevation of left ventricular filling pressure (LVFP) is unknown. However, in patients with\\u000a preexistent cardiac pathologies, it is impossible to differentiate between BNP elevation caused by chronic cardiac abnormalities\\u000a and BNP related to acute neurocardiac injury.\\u000a \\u000a \\u000a \\u000a \\u000a Methods  All adult

Eric Meaudre; Christophe Jego; Nadia Kenane; Ambroise Montcriol; Henry Boret; Philippe Goutorbe; Gilbert Habib; Bruno Palmier

2009-01-01

111

[The first experience with X-ray endovascular closure of the left atrial auricle using an Amplatzer Cardiac Plug in patients with atrial fibrillation].  

PubMed

Atrial fibrillation is the most common cardiac arrhythmia in clinical practice. Long-term anticoagulant therapy is used to prevent thrombosis in the left atrial (LA) auricle and, as a consequence, thrombolisms. However, some patients have contraindications to its use. The paper considers different alternative methods for preventing thromboembolic events and particularly one of the most common presently encountered ones - percutaneous transcatheter LA auricle excision, by applying the Amplatzer Cardiac Plug. There are also data on the authors' experience in using this device. PMID:23700919

Samko, A N; Merkulov, E V; Pevzner, D V; Guchaev, R V; Mironov, V M

2013-01-01

112

Zic3 is required in the extra-cardiac perinodal region of the lateral plate mesoderm for left-right patterning and heart development.  

PubMed

Mutations in ZIC3 cause human X-linked heterotaxy and isolated cardiovascular malformations. A mouse model with targeted deletion of Zic3 demonstrates an early role for Zic3 in gastrulation, CNS, cardiac and left-right axial development. The observation of multiple malformations in Zic3(null) mice and the relatively broad expression pattern of Zic3 suggest its important roles in multiple developmental processes. Here, we report that Zic3 is primarily required in epiblast derivatives to affect left-right patterning and its expression in epiblast is necessary for proper transcriptional control of embryonic cardiac development. However, cardiac malformations in Zic3 deficiency occur not because Zic3 is intrinsically required in the heart but rather because it functions early in the establishment of left-right body axis. In addition, we provide evidence supporting a role for Zic3 specifically in the perinodal region of the posterior lateral plate mesoderm for the establishment of laterality. These data delineate the spatial requirement of Zic3 during left-right patterning in the mammalian embryo, and provide basis for further understanding the molecular mechanisms underlying the complex interaction of Zic3 with signaling pathways involved in the early establishment of laterality. PMID:23184148

Jiang, Zhengxin; Zhu, Lirong; Hu, Lingyun; Slesnick, Timothy C; Pautler, Robia G; Justice, Monica J; Belmont, John W

2013-03-01

113

An Inverse Finite Element Method for Determining the Tissue Compressibility of Human Left Ventricular Wall during the Cardiac Cycle  

PubMed Central

The determination of the myocardium’s tissue properties is important in constructing functional finite element (FE) models of the human heart. To obtain accurate properties especially for functional modeling of a heart, tissue properties have to be determined in vivo. At present, there are only few in vivo methods that can be applied to characterize the internal myocardium tissue mechanics. This work introduced and evaluated an FE inverse method to determine the myocardial tissue compressibility. Specifically, it combined an inverse FE method with the experimentally-measured left ventricular (LV) internal cavity pressure and volume versus time curves. Results indicated that the FE inverse method showed good correlation between LV repolarization and the variations in the myocardium tissue bulk modulus K (K?=?1/compressibility), as well as provided an ability to describe in vivo human myocardium material behavior. The myocardium bulk modulus can be effectively used as a diagnostic tool of the heart ejection fraction. The model developed is proved to be robust and efficient. It offers a new perspective and means to the study of living-myocardium tissue properties, as it shows the variation of the bulk modulus throughout the cardiac cycle. PMID:24367544

Hassaballah, Abdallah I.; Hassan, Mohsen A.; Mardi, Azizi N.; Hamdi, Mohd

2013-01-01

114

Selective PDE5A inhibition with sildenafil rescues left ventricular dysfunction, inflammatory immune response and cardiac remodeling in angiotensin II-induced heart failure in vivo.  

PubMed

Sildenafil inhibits cyclic GMP-specific phosphodiesterase type-5A (PDE5A) and can prevent cardiac hypertrophy and left ventricular (LV) dysfunction in mice subjected to severe pressure-overload. The pathophysiological role of sildenafil in adverse remodeling in the hypertensive heart after chronic renin-angiotensin aldosterone system stimulation is unknown. Therefore, we studied the efficacy of the PDE5A inhibitor sildenafil for treating advanced cardiac hypertrophy and LV remodeling due to angiotensin (Ang)II-induced heart failure (HF) in vivo. C57BL6/J mice were subjected to AngII-induced cardiac hypertrophy for 3 weeks and cardiac dysfunction, cardiac inflammatory stress response, adverse remodeling as well as apoptosis were documented. Mice were subsequently treated with sildenafil (100 mg/kg/day) or placebo with delay of 5 days for treating AngII infusion-induced adverse events. Compared to controls, AngII infusion resulted in impaired systolic (dP/dt (max) -46 %, SV -16 %, SW -43 %, E (a) +51 %, EF -37 %, CO -36 %; p < 0.05) and diastolic (dP/dt (min) -36 %, LV end diastolic pressure +73 %, Tau +21 %, stiffness constant ? +74 %; p < 0.05) LV function. This was associated with a significant increase in cardiac hypertrophy and fibrosis. Increased inflammatory response was also indicated by an increase in immune cell infiltration and apoptosis. Treatment with sildenafil led to a significant improvement in systolic and diastolic LV performance. This effect was associated with less LV hypertrophy, remodeling, cardiac inflammation and apoptosis. PDE5A inhibition with sildenafil may provide a new treatment strategy for cardiac hypertrophy and adverse remodeling in the hypertensive heart. PMID:23117837

Westermann, Dirk; Becher, Peter Moritz; Lindner, Diana; Savvatis, Kostantinos; Xia, Yu; Fröhlich, Matthias; Hoffmann, Sebastian; Schultheiss, Heinz-Peter; Tschöpe, Carsten

2012-11-01

115

Automatic localization of the left ventricle from cardiac cine magnetic resonance imaging: a new spectrum-based computer-aided tool.  

PubMed

Traditionally, cardiac image analysis is done manually. Automatic image processing can help with the repetitive tasks, and also deal with huge amounts of data, a task which would be humanly tedious. This study aims to develop a spectrum-based computer-aided tool to locate the left ventricle using images obtained via cardiac magnetic resonance imaging. Discrete Fourier Transform was conducted pixelwise on the image sequence. Harmonic images of all frequencies were analyzed visually and quantitatively to determine different patterns of the left and right ventricles on spectrum. The first and fifth harmonic images were selected to perform an anisotropic weighted circle Hough detection. This tool was then tested in ten volunteers. Our tool was able to locate the left ventricle in all cases and had a significantly higher cropping ratio of 0.165 than did earlier studies. In conclusion, a new spectrum-based computer aided tool has been proposed and developed for automatic left ventricle localization. The development of this technique, which will enable the automatic location and further segmentation of the left ventricle, will have a significant impact in research and in diagnostic settings. We envisage that this automated method could be used by radiographers and cardiologists to diagnose and assess ventricular function in patients with diverse heart diseases. PMID:24722328

Zhong, Liang; Zhang, Jun-Mei; Zhao, Xiaodan; Tan, Ru San; Wan, Min

2014-01-01

116

Videoscopic Left Cardiac Sympathetic Denervation for Patients With Recurrent Ventricular Fibrillation/Malignant Ventricular Arrhythmia Syndromes Besides Congenital Long-QT Syndrome  

PubMed Central

Background Treatment options for patients with recurrent ventricular arrhythmias refractory to pharmacotherapy and ablation are minimal. Although left cardiac sympathetic denervation (LCSD) is well established in long-QT syndrome, its role in non-long-QT syndrome arrhythmogenic channelopathies and cardiomyopathies is less clear. Here, we report our single-center experience in performing LCSD in this setting. Methods and Results In this institutional review board-approved study, we retrospectively reviewed the electronic medical records of all patients (N=91) who had videoscopic LCSD at our institution from 2005 to 2011. Data were analyzed for the subset (n=27) who were denervated for an underlying diagnosis other than autosomal dominant or sporadic long-QT syndrome. The spectrum of arrhythmogenic disease included catecholaminergic polymorphic ventricular tachycardia (n=13), Jervell and Lange-Nielsen syndrome (n=5), idiopathic ventricular fibrillation (n=4), left ventricular noncompaction (n=2), hypertrophic cardiomyopathy (n=1), ischemic cardiomyopathy (n=1), and arrhythmogenic right ventricular cardiomyopathy (n=1). Five patients had LCSD because of high-risk assessment and ?-blocker intolerance, none of whom had a sentinel breakthrough cardiac event at early follow-up. Among the remaining 22 previously symptomatic patients who had LCSD as secondary prevention, all had an attenuation in cardiac events, with 18 having no breakthrough cardiac events so far and 4 having experienced ?1 post-LCSD breakthrough cardiac event. Conclusions LCSD may represent a substrate-independent antifibrillatory treatment option for patients with life-threatening ventricular arrhythmia syndromes other than long-QT syndrome. The early follow-up seems promising, with a marked reduction in the frequency of cardiac events postdenervation. PMID:22787014

Coleman, Mira A.; Bos, J. Martijn; Johnson, Jonathan N.; Owen, Heidi J.; Deschamps, Claude; Moir, Christopher; Ackerman, Michael J.

2014-01-01

117

Prevention of cardiac fibrosis and left ventricular dysfunction in diabetic cardiomyopathy in rats by transgenic expression of the human tissue kallikrein gene  

Microsoft Academic Search

Diabetic cardiomyopathy includes fibro- sis. Kallikrein (KLK) can inhibit collagen synthesis and promote collagen breakdown. We investigated cardiac fibrosis and left ventricular (LV) function in transgenic rats (TGR) expressing the human kallikrein 1 (hKLK1) gene in streptozotocin (STZ) -induced diabetic condi- tions. Six weeks after STZ injection, LV function was determined in male Sprague-Dawley (SD) rats and TGR(hKLK1) (n10\\/group) by

CARSTEN TSCHOPE; THOMAS WALTHER; JENS KONIGER; FRANK SPILLMANN; DIRK WESTERMANN; FELICITAS ESCHER; MATTHIAS PAUSCHINGER; JOAO B. PESQUERO; MICHAEL BADER; HEINZ-PETER SCHULTHEISS; MICHEL NOUTSIAS

2004-01-01

118

Biomarkers of Chronic Cardiac Injury and Hemodynamic Stress Identify a Malignant Phenotype of Left Ventricular Hypertrophy in the General Population  

PubMed Central

Objectives To determine if biomarkers of subclinical myocardial injury and hemodynamic stress identify asymptomatic individuals with left ventricular hypertrophy (LVH) at higher risk for heart failure (HF) and death. Background The interaction between LVH, low but detectable cardiac troponin T (cTnT), and elevated NT-proBNP on cardiovascular (CV) outcomes in the general population is unknown. Methods Participants in the Dallas Heart Study without clinical HF, LV dysfunction, or chronic kidney disease underwent measurement of LV mass by MRI, cTnT by highly sensitive assay, and NT-proBNP (n=2413). Subjects were stratified by LVH and by detectable cTnT (?3 pg/mL) and increased NT-proBNP (>75th age- and sex-specific percentile). Results 9% of participants were LVH+, 25% cTnT+, and 24% NT-proBNP+. Those LVH+ and cTnT+ and/or NT-proBNP+ (n=144) were older, more likely to be male, with greater risk factor burden and more severe LVH compared with those LVH+ biomarker- (p<0.01 for each). The cumulative incidence of HF or CV death over 8 years among LVH+ cTnT+ was 21% vs. 1% (LVH- cTnT-), 4% (LVH- cTnT+), and 6% (LVH+ cTnT-), p<0.0001. The interactions between LVH and cTnT (pinteraction=0.0005) and LVH and NT-proBNP (pinteraction=0.014) were highly significant. Individuals LVH+ and either cTnT+ or NT-proBNP+ remained at >4-fold higher risk for HF or CV death after multivariable adjustment for CV risk factors, renal function, and LV mass compared with those LVH- biomarker-. Conclusions Minimal elevations in biomarkers of subclinical cardiac injury and hemodynamic stress modify the association of LVH with adverse outcomes, identifying a malignant sub-phenotype of LVH with high risk for progression to HF and CV death. PMID:23219305

Neeland, Ian J.; Drazner, Mark H.; Berry, Jarett D.; Ayers, Colby R.; deFilippi, Christopher; Seliger, Stephen L.; Nambi, Vijay; McGuire, Darren K.; Omland, Torbjørn; de Lemos, James A.

2012-01-01

119

Commonalities of Cardiac Rupture (Left Ventricular Free Wall or Ventricular Septum or Papillary Muscle) During Acute Myocardial Infarction Secondary to Atherosclerotic Coronary Artery Disease.  

PubMed

Although mortality rates during acute myocardial infarction (AMI) continue to drop, cardiac rupture (left ventricular free wall [LVFW] or ventricular septum [VS] or papillary muscle [PM] or combination) remains relatively common. The aim was to identify commonalities among patients with AMI complicated by cardiac rupture. During a 22-year period (1993-2014) 64 patients hospitalized for AMI were studied and clinical and morphologic variables in those with (25 patients) - vs - those without (39 patients) cardiac rupture were compared, and previous reports on this topic were reviewed. Compared to the non-rupture cases, the rupture group was significantly older (71 years - vs - 60 years); had a much higher frequency of huge deposits of adipose tissue in the heart (floated in formaldehyde) (88% - vs - 20%) but a lower mean body mass index (28.2 Kg/m(2) - vs - 33.2 Kg/m(2)); a much lower frequency of healed myocardial infarct (scar) (4% - vs - 28%); a lower frequency of diabetes mellitus (24% - vs - 47%), and a higher frequency of thrombolytic therapy during the fatal AMI (32% - vs - 10%). None of the rupture cases had evidence of dilated left ventricular cavities or evidence of heart failure before the AMI complicated by rupture. In conclusion, cardiac rupture appears to account for a high percent of deaths during a first AMI. It most commonly occurs in patients with extremely fatty hearts and in those without evidence of prior heart failure. PMID:25456862

Roberts, William C; Burks, Kendall H; Ko, Jong Mi; Filardo, Giovanni; Guileyardo, Joseph M

2015-01-01

120

Analysis of in vivo left atrial appendage morphology in patients with atrial fibrillation: a direct comparison of transesophageal echocardiography, planar cardiac CT, and segmented three-dimensional cardiac CT  

Microsoft Academic Search

Purpose  Recent development of percutaneous left atrial appendage (LAA) occlusion devices has underscored the need for an accurate\\u000a understanding of LAA morphology and the interchangeability of results from differing imaging modalities. The purpose of this\\u000a study is to assess LAA morphology and location in AF patients, directly comparing transesophageal echocardiography (TEE),\\u000a planar cardiac computed tomography (CT), and three-dimensional segmented CT reconstructions.

Loren P. Budge; Katherine M. Shaffer; J. Randall Moorman; Douglas E. Lake; John D. Ferguson; J. Michael Mangrum

2008-01-01

121

Hydrogen sulfide suppresses the expression of MMP-8, MMP-13, and TIMP-1 in left ventricles of rats with cardiac volume overload  

PubMed Central

Aim: To study the effects of hydrogen sulfide (H2S) on the left ventricular expression of MMP-8, MMP-13, and TIMP-1 in a rat model of congenital heart disease. Methods: Male SD rats underwent abdominal aorta-inferior vena cava shunt operation. H2S donor NaHS (56 ?mol·kg?1·d?1, ip) was injected from the next day for 8 weeks. At 8 weeks, the hemodynamic parameters, including the left ventricular systolic pressure (LVSP), the left ventricular peak rate of contraction and relaxation (LV±dp/dtmax) and the left ventricular end diastolic pressure (LVEDP) were measured. The left ventricular tissues were dissected out, and hydroxyproline and collagen I contents were detected with ELISA. The expression of MMP-8, MMP-13, and a tissue inhibitor of metalloproteinase-1 (TIMP-1) in the tissues was measured using real-time PCR, Western blotting, and immunohistochemistry, respectively. Results: The shunt operation markedly reduced LVSP and LV±dp/dtmax, increased LVEDP, hydroxyproline and collagen I contents, as well as the mRNA and protein levels of MMP-8, MMP-13, and TIMP-1 in the left ventricles. Chronic treatment of the shunt operation rats with NaHS effectively prevented the abnormalities in the hemodynamic parameters, hydroxyproline and collagen I contents, and the mRNA and protein levels of MMP-13 and TIMP-1 in the left ventricles. NaHS also prevented the increase of MMP-8 protein expression, but did not affect the increase of mRNA level of MMP-8 in the shunt operation rats. Conclusion: H2S suppresses protein and mRNA expression of MMP-8, MMP-13, and TIMP-1 in rats with cardiac volume overload, which may be contributed to the amelioration of ventricular structural remodeling and cardiac function. PMID:23974514

Zhang, Chao-ying; Li, Xiao-hui; Zhang, Ting; Fu, Jin; Cui, Xiao-dai

2013-01-01

122

Statistical agreement of left ventricle measurements using cardiac magnetic resonance and 2D echocardiography in ischemic heart failure  

PubMed Central

Summary Background The aim of this study was to compare cardiac magnetic resonance imaging (CMR) with 2-dimensional echocardiography (2D echo) in the assessment of left ventricle (LV) function parameters and mass in patients with ischemic heart disease and severely depressed LV function. Although 2D echo is commonly used to assess LV indices, CMR is the state-of-the-art technique. Agreement between these 2 methods in these patients has not been well established. Material/Methods LV indexed end systolic and diastolic volumes (EDVi and ESVi), indexed mass (LVMi) and ejection fraction (EF) were assessed in 67 patients (12 women), using 2D echo and CMR. Results According to statistical analysis (Bland-Altman), 2D echo underestimated LV EDV and ESV and overestimated EF and LVMi compared to CMR. The highest correlation between 2D echo and CMR was found for EDVi (R2=0.73, p<0.0001) and ESVi (R2=0.69, p<0.0001) and the lowest for EF (R2=0.21, p=0.001) and LVMi (R2=0.20, p=0.002). The maximal differences between 2D echo and CMR were found for highest mesurements of LV volumes and mass, and for lowest EF values. Conclusions There is moderate to strong correlation between CMR and 2D echo in the assessment of LV function parameters and mass in patients with ischemic heart failure. Between-method agreement depends on the degree of LV dysfunction. The results of assessment of the severely damaged LV obtained by the use of 2D echo should be interpreted with caution. PMID:22367134

Gruszczy?ska, Katarzyna; Krzych, ?ukasz J.; Go?ba, Krzysztof S.; Biernat, Jolanta; Roleder, Tomasz; Deja, Marek A.; Ulbrych, Piotr; Malinowski, Marcin; Janusiewicz, Piotr; Wo?, Stanis?aw; Baron, Jan

2012-01-01

123

Usefulness of echo-guided cardiac resynchronization pacing in patients undergoing "ablate and pace" therapy for permanent atrial fibrillation and effects of heart rate regularization and left ventricular resynchronization.  

PubMed

An acute comparative study of right ventricular (RV) pacing and echocardiographically guided cardiac resynchronization pacing (CRP) was performed in patients who underwent "ablate and pace" therapy for permanent atrial fibrillation. It was hypothesized that optimized CRP guided by tissue Doppler echocardiography would exert an additive beneficial hemodynamic effect to that of rate regularization achieved through atrioventricular junction ablation. An acute intrapatient comparison of echocardiographic parameters was performed between baseline preablation values and RV pacing and CRP (performed <24 hours after ablation) in 50 patients. Optimized CRP configuration was defined as the modality of pacing corresponding to that of the shortest intra-left ventricular (LV) delay among simultaneous biventricular pacing, sequential biventricular pacing, and single-chamber pacing. The intra-LV delay was defined as the difference between the longest and the shortest activation time in the six basal segments of the left ventricle. Compared with preablation measures, the ejection fraction increased by 10.8% during RV pacing (19% in patients with intra-LV delays <47.5 ms and 3% in those with intra-LV delays >47.5 ms). Compared with RV pacing, CRP caused a 9.2% increase in the ejection fraction, a 6.8% decrease in LV systolic diameter, and a 17.3% decrease in mitral regurgitation area; LV dyssynchrony was reduced from 52 +/- 27 to 21 +/- 12 ms. Similar results were observed in patients with and without depressed systolic function and in patients with and without left bundle branch block. In conclusion, rate regularization achieved through atrioventricular junction ablation and RV pacing provides a favorable hemodynamic effect that is inversely related to the level of LV dyssynchrony. Minimizing LV dyssynchrony by means of optimized CRP yields an additional important benefit. PMID:18805110

Brignole, Michele; Menozzi, Carlo; Botto, Gian Luca; Mont, Lluís; Osca Asensi, Joaquín; García Medina, Dolores; Oddone, Daniele; Navazio, Alessandro; Luzi, Mario; Iacopino, Saverio; De Fabrizio, Giuseppe; Proclemer, Alessandro; Vardas, Panos

2008-10-01

124

Pericardial tamponade after left posterolateral thoracotomy for left upper lobectomy for pulmonary aspergilloma.  

PubMed

Pericardial tamponade limits diastolic filling of the heart; therefore, a high venous pressure is required to fill the ventricle. In presence of cardiac tamponade, therapeutic agents and manoeuvres that results in venodilation or vasodilation can severely compromise diastolic filling of the heart and might result in rapid cardiac decompensation. Equalization of central venous pressure and pulmonary artery diastolic pressure or equalization of pressures in all four chambers during diastole confirms cardiac tamponade. Transthoracic echocardiography can detect the site of tamponade and assist in pericardiocentesis. We describe acute pericardial tamponade in a young man who underwent left posterolateral thoracotomy for left upper lobectomy. Intraoperatively, mobilization of the left upper lobe was frequently associated with hypotension. Postoperatively, the patient suffered two more episodes of hypotension. The episodes of hypotension were attributed to surgical manipulation and epidural blockade. Hemodynamics normalized after discontinuing epidural infusion, volume resuscitation and lobectomy. On third postoperative day, the patient developed cardiovascular collapse; arterial blood pressure and central venous pressure were 70/50 and 12 mmHg. Investigations showed haziness of left lung, and severe respiratory acidosis. On opening of the left thoracotomy wound, pericardial tamponade was diagnosed. A pericardial window was created and tamponade was released with that the hemodynamics normalized. Episodes of unexplained hypotension after left upper lobectomy suggest a cardiac etiology and acute pericardial tamponade is a possibility which should be released immediately otherwise it can result in fatal outcome. PMID:21636931

Neema, Praveen Kumar; Shah, Hetal; Sethuraman, Manikandan; Rathod, Ramesh Chandra

2011-01-01

125

Postmortem mRNA expression patterns in left ventricular myocardial tissues and their implications for forensic diagnosis of sudden cardiac death.  

PubMed

Sudden cardiac death (SCD), which is primarily caused by lethal heart disorders resulting in structural and arrhythmogenic abnormalities, is one of the prevalent modes of death in most developed countries. Myocardial ischemia, mainly due to coronary artery disease, is the most common type of heart disease leading to SCD. However, postmortem diagnosis of SCD is frequently complicated by obscure histological evidence. Here, we show that certain mRNA species, namely those encoding hemoglobin A1/2 and B (Hba1/2 and Hbb, respectively) as well as pyruvate dehydrogenase kinase 4 (Pdk4), exhibit distinct postmortem expression patterns in the left ventricular free wall of SCD subjects when compared with their expression patterns in the corresponding tissues from control subjects with non-cardiac causes of death. Hba1/2 and Hbb mRNA expression levels were higher in ischemic SCD cases with acute myocardial infarction or ischemic heart disease without recent infarction, and even in cardiac death subjects without apparent pathological signs of heart injuries, than control subjects. By contrast, Pdk4 mRNA was expressed at lower levels in SCD subjects. In conclusion, we found that altered myocardial Hba1/2, Hbb, and Pdk4 mRNA expression patterns can be employed as molecular signatures of fatal cardiac dysfunction to forensically implicate SCD as the primary cause of death. PMID:24642708

Son, Gi Hoon; Park, Seong Hwan; Kim, Yunmi; Kim, Ji Yeon; Kim, Jin Wook; Chung, Sooyoung; Kim, Yu-Hoon; Kim, Hyun; Hwang, Juck-Joon; Seo, Joong-Seok

2014-03-01

126

Construction of a two-parameter empirical model of left ventricle wall motion using cardiac tagged magnetic resonance imaging data  

E-print Network

visualized using cardiac tagged magnetic resonance imaging (tMRI) covering the contraction and relaxation phases. Based on the characteristics of the overall dynamics of the LV wall, its motion was represented by a combination of two components - radial...

Shi, Jack J; Alenezy, Mohammed D.; Smirnova, Irina V.; Bilgen, Mehmet

2012-10-24

127

A Comprehensive Analysis of Cardiac Dose in Balloon-Based High-Dose-Rate Brachytherapy for Left-Sided Breast Cancer  

SciTech Connect

Purpose: To investigate radiation dose to the heart in 60 patients with left-sided breast cancer who were treated with balloon-based high-dose-rate brachytherapy using MammoSite or Contura applicators. Methods and Materials: We studied 60 consecutive women with breast cancer who were treated with 34 Gy in 10 twice-daily fractions using MammoSite (n = 37) or Contura (n = 23) applicators. The whole heart and the left and right ventricles were retrospectively delineated, and dose-volume histograms were analyzed. Multiple dosimetrics were reported, such as mean dose (D{sub mean}); relative volume receiving 1.7, 5, 10, and 20 Gy (V1.7, V5, V10, and V20, respectively); dose to 1 cc (D{sub 1cc}); and maximum point dose (D{sub max}). Biologic metrics, biologically effective dose and generalized equivalent uniform dose were computed. The impact of lumpectomy cavity location on cardiac dose was investigated. Results: The average {+-} standard deviation of D{sub mean} was 2.45 {+-} 0.94 Gy (range, 0.56-4.68) and 3.29 {+-} 1.28 Gy (range, 0.77-6.35) for the heart and the ventricles, respectively. The average whole heart V5 and V10 values were 10.2% and 1.3%, respectively, and the heart D{sub max} was >20 Gy in 7 of 60 (11.7%) patients and >25 Gy in 3 of 60 (5%) patients. No cardiac tissue received {>=}30 Gy. The V1.7, V5, V10, V20, and D{sub mean} values were all higher for the ventricles than for the whole heart. For balloons located in the upper inner quadrant of the breast, the average whole heart D{sub mean} was highest. The D{sub mean}, biologically effective dose, and generalized equivalent uniform dose values for heart and ventricles decreased with increasing minimal distance from the surface of the balloon. Conclusions: On the basis of these comprehensive cardiac dosimetric data, we recommend that cardiac dose be routinely reported and kept as low as possible in balloon-based high-dose-rate brachytherapy treatment planning for patients with left-sided breast cancer so the correlation with future cardiac toxicity data can be investigated.

Valakh, Vladimir, E-mail: vladimir@valakh.com [Department of Radiation Oncology, Allegheny General Hospital, Pittsburgh, PA (United States); Kim, Yongbok; Werts, E. Day; Trombetta, Mark G. [Department of Radiation Oncology, Allegheny General Hospital, Pittsburgh, PA (United States); Drexel University College of Medicine, Allegheny Campus, Pittsburgh, PA (United States)

2012-04-01

128

3D left ventricular extracellular volume fraction by low-radiation dose cardiac CT: Assessment of interstitial myocardial fibrosis  

PubMed Central

Background Myocardial fibrosis leads to impaired cardiac function and events. Extracellular volume fraction (ECV) assessed with an iodinated contrast agent and measured by cardiac CT may be a useful noninvasive marker of fibrosis. Objective The purpose of this study was to develop and evaluate a 3-dimensional (3D) ECV calculation toolkit (ECVTK) for ECV determination by cardiac CT. Methods Twenty-four subjects (10 systolic heart failure, age, 60 ± 17 years; 5 diastolic failure, age 56 ± 20 years; 9 matched healthy subjects, age 59 ± 7 years) were evaluated. Cardiac CT examinations were done on a 320-multidetector CT scanner before and after 130 mL of iopamidol (Isovue-370; Bracco Diagnostics, Plainsboro, NJ, USA) was administered. A calcium score type sequence was performed before and 7 minutes after contrast with single gantry rotation during 1 breath hold and single cardiac phase acquisition. ECV was calculated as (?HUmyocardium/?HUblood) × (1 ? Hct) where Hct is the hematocrit, and ?HU is the change in Hounsfield unit attenuation = HUafter iodine ? HUbefore iodine. Cardiac magnetic resonance imaging was performed to assess myocardial structure and function. Results Mean 3D ECV values were significantly higher in the subjects with systolic heart failure than in healthy subjects and subjects with diastolic heart failure (mean, 41% ± 6%, 33% ± 2%, and 35% ± 5%, respectively; P = 0.02). Interobserver and intraobserver agreements were excellent for myocardial, blood pool, and ECV (intraclass correlation coefficient, >0.90 for all). Higher 3D ECV by cardiac CT was associated with reduced systolic circumferential strain, greater end-diastolic and -systolic volumes, and lower ejection fraction (r = 0.70, r = 0.60, r = 0.73, and r = ?0.68, respectively; all P < 0.001). Conclusion 3D ECV by cardiac CT can be performed with ECVTK. We demonstrated increased ECV in subjects with systolic heart failure compared with healthy subjects. Cardiac CT results also showed good correlation with important functional heart biomarkers, suggesting the potential for myocardial tissue characterization with the use of 3D ECV by cardiac CT. This trial is registered at www.ClinicalTrials.gov as NCT01160471. PMID:23333188

Nacif, Marcelo Souto; Liu, Yixun; Yao, Jianhua; Liu, Songtao; Sibley, Christopher T.; Summers, Ronald M.; Bluemke, David A.

2014-01-01

129

Relationship between changes of chamber mechanical parameters and mean pressure-mean flow diagrams of the left ventricle.  

PubMed

A theoretical relationship between mean ventricular pressure (P) and mean ventricular outflow (Q) was developed based on a model of the left ventricle with elastic-resistive properties. Using a polynomial interpolation method, a fifth-order polynomial equation for the P-Q relationship was obtained. Its coefficients are functions of end-diastolic volume (VD), heart rate (HR), contractile state (CS), diastolic elastance (ED), asymmetry (S) of the elastance function E(t), and ventricular internal resistance factor (K). Effect of changes of these parameters indicated that normal and enhanced CS relations diverge toward the P axis but have a common intercept toward the Q axis. A similar effect was obtained with increased asymmetry of E(t). Changes in VD, HR and ED produced a parallel shift of the P-Q relation. The effect of K was negligible, however, which would reduce the description of the P-Q relationship to a third-order polynomial equation. A flow-dependent deactivation component was introduced, altering the asymmetry factor S, which decreases in a linear proportion to Q. This factor shifted the pump function graph downwards. We conclude that the theoretical description of the P-Q relation we present reproduces the experimental behavior of pump function diagrams reported in the literature (changes in VD, HR, and CS) and predicts the possible behavior due to other parameter changes. PMID:3400909

Negroni, J A; Lascano, E C; Pichel, R H

1988-01-01

130

A Rare Case of Congenital Heart Disease with Bifid Cardiac Apex: A Unique Finding in Left Ventricle  

PubMed Central

Bifid cardiac apex is a rare anomaly of human hearts. We report of the case of a 34-year-old man with a previous history of ventricular septal defect (VSD) and subvalvular pulmonary stenosis. He had undergone pulmonary commissurotomy and VSD closure 22 years before he was referred to our center for evaluation of progressive dyspnea. Transthoracic echocardiography revealed atrial septal defect (ASD), multiple VSDs, severe pulmonary regurgitation, and a bifid cardiac apex. The patient was referred for re-do surgery for ASD and VSD closure along with pulmonary valve replacement, but he refused the surgery. PMID:24396366

Maleki, Majid; Esmaeilzadeh, Maryam; Alizadeasl, Azin; Hashemi, Arash

2013-01-01

131

Long-term antihypertensive treatment fails to improve E/e' despite regression of left ventricular mass: an Anglo-Scandinavian cardiac outcomes trial substudy.  

PubMed

Antihypertensive treatment can improve tissue Doppler indices of left ventricular diastolic function in the short term, but little is known about the longer-term effect of different antihypertensive treatments on progression of left ventricular diastolic function and left ventricular hypertrophy. We hypothesized that long-term treatment of hypertension will lead to improvements in left ventricular hypertrophy and diastolic function. We collected detailed cardiovascular phenotypic data on 1006 participants from a substudy of the Anglo-Scandinavian Cardiac Outcomes Trial. Patients randomized to either an amlodipine±perindopril-based or an atenolol±bendroflumethiazide-based regimen underwent conventional and tissue Doppler echocardiography at time of control of blood pressure after randomization (?1.5 years; phase 1) and after a further 2 years of antihypertensive treatment (phase 2). There were no prerandomization data. Five hundred thirty-six patients had complete data collection at both phases. Left ventricular mass index regressed from phase 1 to 2 with no significant difference between treatment groups (amlodipine: 119.5-116.8; atenolol: 122.9-117.5; P<0.001 for both). Conversely, tissue Doppler diastolic indices did not change in the amlodipine±perindopril-based regimen (E/e', 7.5-7.6 cm/s; P=not significant), but deteriorated in the atenolol±bendroflumethiazide-based regimen (E/e', 8.0-8.5 cm/s; P<0.01). Despite regression of left ventricular hypertrophy, there was no associated improvement in diastolic function. In fact, long-term treatment with atenolol±bendroflumethiazide resulted in a progressive deterioration in E/e'. This may be a factor contributing to the previously described worse clinical outcome in patients treated with atenolol±bendroflumethiazide compared with amlodipine±perindopril. PMID:24218432

Barron, Anthony J; Hughes, Alun D; Sharp, Andrew; Baksi, Arun J; Surendran, Praveen; Jabbour, Richard J; Stanton, Alice; Poulter, Neil; Fitzgerald, Des; Sever, Peter; O'Brien, Eoin; Thom, Simon; Mayet, Jamil

2014-02-01

132

Impact of the bifurcation angle on major cardiac events after cross-over single stent strategy in unprotected left main bifurcation lesions: 3-dimensional quantitative coronary angiographic analysis  

PubMed Central

The impact of the bifurcation angle (BA) between the left main (LM) and the main branch on clinical outcomes after single stenting has never been documented. Therefore, the aim of this study was to investigate the impact of the BA on clinical outcomes after single cross-over LM to left anterior descending artery (LAD) stenting. A total of 170 patients who underwent percutaneous coronary intervention (PCI) in unprotected LM bifurcation with successful single cross-over stenting from the LM into the LAD were enrolled. The main vessel angle between the LM and the LAD was computed in end-diastole before PCI with three-dimensional (3D) quantitative coronary angiography (QCA) software. The patients were classified into three groups according to tertiles of the main vessel angle. The cumulative incidence of major adverse cardiac event (MACE: cardiac death, myocardial infarction, any revascularization including target lesion revascularization) rates throughout a 12-month period were compared between the three groups. Baseline patient characteristics were not a significant difference between the three groups. Compared to the high angle group, the low angle group had a significantly higher incidence of MACE (p = 0.041). In conclusion, this study revealed that low BA between the LM and the LAD had an adverse clinical impact after single cross-over LM to LAD stenting. PMID:25628958

Amemiya, Kisaki; Domei, Takenori; Iwabuchi, Masashi; Shirai, Shinichi; Ando, Kenji; Goya, Masahiko; Yokoi, Hiroyoshi; Nobuyoshi, Masakiyo

2014-01-01

133

N-Terminal Pro-B-Type Natriuretic Peptide Plasma Levels as a Potential Biomarker for Cardiac Damage After Radiotherapy in Patients With Left-Sided Breast Cancer  

SciTech Connect

Purpose: Adjuvant radiotherapy (RT) after breast-conserving surgery has been associated with increased cardiovascular mortality. Cardiac biomarkers may aid in identifying patients with radiation-mediated cardiac dysfunction. We evaluated the correlation between N-terminal pro-B-type natriuretic peptide (NT-proBNP) and troponin (TnI) and the dose of radiation to the heart in patients with left-sided breast cancer. Methods and Materials: NT-proBNP and TnI plasma concentrations were measured in 30 left-sided breast cancer patients (median age, 55.0 years) 5 to 22 months after RT (Group I) and in 30 left-sided breast cancer patients (median age, 57.0 years) before RT as control group (Group II). Dosimetric and geometric parameters of heart and left ventricle were determined in all patients of Group I. Seventeen patients underwent complete two-dimensional echocardiography. Results: NT-proBNP levels were significantly higher (p = 0.03) in Group I (median, 90.0 pg/ml; range, 16.7-333.1 pg/ml) than in Group II (median, 63.2 pg/ml; range, 11.0-172.5 pg/ml). TnI levels remained below the cutoff threshold of 0.07 ng/ml in both groups. In patients with NT-proBNP values above the upper limit of 125 pg/ml, there were significant correlations between plasma levels and V{sub 3Gy}(%) (p = 0.001), the ratios D{sub 15cm{sup 3}}(Gy)/D{sub mean}(Gy) (p = 0.01), the ratios D{sub 15cm}{sup 3}/D{sub 50%} (Gy) (p = 0.008) for the heart and correlations between plasma levels and V{sub 2Gy} (%) (p = 0.002), the ratios D{sub 1cm{sup 3}}(Gy)/D{sub mean}(Gy) (p = 0.03), and the ratios D{sub 0.5cm{sup 3}}(Gy)/D{sub 50%}(Gy) (p = 0.05) for the ventricle. Conclusions: Patients with left-sided breast cancer show higher values of NT-pro BNP after RT when compared with non-RT-treated matched patients, increasing in correlation with high doses in small volumes of heart and ventricle. The findings of this study show that the most important parameters are not the mean doses but instead the small percentage of organ volumes (heart or ventricle) receiving high dose levels, supporting the notion that the heart behaves as a serial organ.

D'Errico, Maria P., E-mail: patderrico@libero.it [Department of Laboratory Medicine, 'A. Perrino' Hospital, Brindisi (Italy); Grimaldi, Luca [Department of Medical Physics, 'A. Perrino' Hospital, Brindisi (Italy); Petruzzelli, Maria F. [Department of Radiation Oncology, 'A. Perrino' Hospital, Brindisi (Italy); Gianicolo, Emilio A.L. [Clinical Physiology Institute, National Research Council (IFC-CNR), Pisa-Lecce (Italy); Tramacere, Francesco [Department of Radiation Oncology, 'A. Perrino' Hospital, Brindisi (Italy); Monetti, Antonio; Placella, Roberto [Department of Laboratory Medicine, 'A. Perrino' Hospital, Brindisi (Italy); Pili, Giorgio [Department of Medical Physics, 'A. Perrino' Hospital, Brindisi (Italy); Andreassi, Maria Grazia; Sicari, Rosa; Picano, Eugenio [Clinical Physiology Institute, National Research Council (IFC-CNR), Pisa-Lecce (Italy); Portaluri, Maurizio [Department of Radiation Oncology, 'A. Perrino' Hospital, Brindisi (Italy); Clinical Physiology Institute, National Research Council (IFC-CNR), Pisa-Lecce (Italy)

2012-02-01

134

Assessment of dedicated low-dose cardiac micro-CT reconstruction algorithms using the left ventricular volume of small rodents as a performance measure  

SciTech Connect

Purpose: Phase-correlated microcomputed tomography (micro-CT) imaging plays an important role in the assessment of mouse models of cardiovascular diseases and the determination of functional parameters as the left ventricular volume. As the current gold standard, the phase-correlated Feldkamp reconstruction (PCF), shows poor performance in case of low dose scans, more sophisticated reconstruction algorithms have been proposed to enable low-dose imaging. In this study, the authors focus on the McKinnon-Bates (MKB) algorithm, the low dose phase-correlated (LDPC) reconstruction, and the high-dimensional total variation minimization reconstruction (HDTV) and investigate their potential to accurately determine the left ventricular volume at different dose levels from 50 to 500 mGy. The results were verified in phantom studies of a five-dimensional (5D) mathematical mouse phantom. Methods: Micro-CT data of eight mice, each administered with an x-ray dose of 500 mGy, were acquired, retrospectively gated for cardiac and respiratory motion and reconstructed using PCF, MKB, LDPC, and HDTV. Dose levels down to 50 mGy were simulated by using only a fraction of the projections. Contrast-to-noise ratio (CNR) was evaluated as a measure of image quality. Left ventricular volume was determined using different segmentation algorithms (Otsu, level sets, region growing). Forward projections of the 5D mouse phantom were performed to simulate a micro-CT scan. The simulated data were processed the same way as the real mouse data sets. Results: Compared to the conventional PCF reconstruction, the MKB, LDPC, and HDTV algorithm yield images of increased quality in terms of CNR. While the MKB reconstruction only provides small improvements, a significant increase of the CNR is observed in LDPC and HDTV reconstructions. The phantom studies demonstrate that left ventricular volumes can be determined accurately at 500 mGy. For lower dose levels which were simulated for real mouse data sets, the HDTV algorithm shows the best performance. At 50 mGy, the deviation from the reference obtained at 500 mGy were less than 4%. Also the LDPC algorithm provides reasonable results with deviation less than 10% at 50 mGy while PCF and MKB reconstruction show larger deviations even at higher dose levels. Conclusions: LDPC and HDTV increase CNR and allow for quantitative evaluations even at dose levels as low as 50 mGy. The left ventricular volumes exemplarily illustrate that cardiac parameters can be accurately estimated at lowest dose levels if sophisticated algorithms are used. This allows to reduce dose by a factor of 10 compared to today's gold standard and opens new options for longitudinal studies of the heart.

Maier, Joscha, E-mail: joscha.maier@dkfz.de [Medical Physics in Radiology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg (Germany)] [Medical Physics in Radiology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg (Germany); Sawall, Stefan; Kachelrieß, Marc [Medical Physics in Radiology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany and Institute of Medical Physics, University of Erlangen–Nürnberg, 91052 Erlangen (Germany)] [Medical Physics in Radiology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany and Institute of Medical Physics, University of Erlangen–Nürnberg, 91052 Erlangen (Germany)

2014-05-15

135

[Effects of Shenmai injection on afterdepolarization and triggered activities in left ventricular papillary muscle in rat cardiac hypertrophy].  

PubMed

This study is to evaluate the effects of Shenmai injection on the temporal alterations of action potential (AP), early afterdepolarization (EAD) and delayed afterdepolarization (DAD) in papillary muscles. The action potentials were recorded by a glass electrode. APD at 90% repolarization (APD9 ) was measured, and spontaneous EAD and DAD were observed. The results show APD90 was significantly prolonged in model group compared with sham-operated group, whereas it was remained unchanged in Shenmai injec- tion treatment group and amiodarone group. The spontaneous EADs and DADs were frequently visible in model group. In conclusion, EAD, DAD and trigger activities increase gradually during pathological progression of rat cardiac hypertrophy, and Shenmai injection could improve the action potential change in rat cardiac hypertrophy. PMID:25507562

Jiao, Hong; Wang, Xiao-Ling; Chen, Yan-Jing; Xiang, Li-Hua; Zhang, Sheng-Nan

2014-08-01

136

[Effects of Shenmai injection on afterdepolarization and triggered activities in left ventricular papillary muscle in rat cardiac hypertrophy].  

PubMed

This study is to evaluate the effects of Shenmai injection on the temporal alterations of action potential (AP), early afterdepolarization (EAD) and delayed afterdepolarization (DAD) in papillary muscles. The action potentials were recorded by a glass electrode. APD at 90% repolarization (APD9 ) was measured, and spontaneous EAD and DAD were observed. The results show APD90 was significantly prolonged in model group compared with sham-operated group, whereas it was remained unchanged in Shenmai injec- tion treatment group and amiodarone group. The spontaneous EADs and DADs were frequently visible in model group. In conclusion, EAD, DAD and trigger activities increase gradually during pathological progression of rat cardiac hypertrophy, and Shenmai injection could improve the action potential change in rat cardiac hypertrophy. PMID:25423840

Jiao, Hong; Wang, Xiao-Ling; Chen, Yan-Jing; Xiang, Li-Hua; Zhang, Sheng-Nan

2014-08-01

137

Transient left ventricular systolic dysfunction following surgical closure of large patent ductus arteriosus among children and adolescents operated at the cardiac centre, Ethiopia  

PubMed Central

Background Patent ductus arteriosus (PDA) is one of the commonest congenital heart diseases that require closure within the first few months after birth. The residential area of patients affects the size of the PDA: living in highlands, like most places in Ethiopia, is a risk for having larger sized PDA. Closure of these congenital heart defects is usually performed at an early age in places where capable centers are available. In Ethiopia, closure of these defects is done on mission basis often at an older age. Recently, limited reports came about the occurrence of postoperative left ventricular systolic dysfunction (POLVD) following closure of PDA though full explanation is still lacking. Objective To determine the rate of and time to improvement of POLVD and the factors associated with it in children and adolescents who underwent surgical closure of PDA. Method All children and adolescents who underwent surgical closure of PDA at the Cardiac Center, Ethiopia (CCE) had postoperative follow up with echocardiography. Serial left ventricular ejection fraction (LVEF) and fiber shortening (FS) values were recorded for all of them. SPSS 20 was used to analyze the data. Results A total of 36 children and adolescents who underwent surgical closure of PDA from January 2009 to December 2012 and who fulfilled the inclusion criteria were studied. Their mean age at intervention was 8.52 years (SD?=?5.23 years), 77.80% were females. The mean duct size as determined by either echocardiography or intra-operative by the surgeon was 10.31 mm (SD?=?3.20 mm). They were followed for a mean duration of 24.80 months (SD?=?12.36 months) following surgical closure of PDA. The mean LVEF and FS decreased from 65.06% and 35.28% preoperatively to 54.83% and 28.40% post-operatively respectively. Fifteen (42.86%) of the patients had a post-operative LVEF of less than 55%. The mean time to normalization of systolic function was 5.11 weeks (SD?=?3.30 weeks). Having an associated cardiac lesion was an independent predictor of POLVD. Conclusions We conclude that there is a high rate of POLVD following surgical closure of large PDA in highlanders. We recommend a serial and systematic follow up of these children postoperatively. Those with a significant cardiac dysfunction may need cardiac medications like Angiotensin Converting Enzyme Inhibitors (ACEI). PMID:23721219

2013-01-01

138

Finite element stress analysis of the human left ventricle whose irregular shape is developed from single plane cineangiocardiogram.  

PubMed

The three-dimensional left ventricular chamber geometrical model is developed from single plane cineangiocardiogram. This left ventricular model is loaded by an internal pressure monitored by cardiac catheterization. The resulting stresses in the left ventricular model chamber's wall are determined by computerized finite element procedure. For the discretization of this left ventricular model structure, a 20-node, isoparametric finite element is employed. The analysis and formulation of the computerised procedure is presented in the paper, along with the detailed algorithms and computer programs. The procedure is applied to determine the stresses in a left ventricle at an instant, during systole. Next, a portion (represented by a finite element) of this left ventricular chamber is simulated as being infarcted by making its active-state modulus value equal to its passive-state value; the neighbouring elements are shown to relieve the "infarcted" element of stress by themselves taking on more stress. PMID:891161

Ghista, D N; Hamid, M S

1977-09-01

139

Value of baseline left lateral wall postsystolic displacement assessed by M-mode to predict reverse remodeling by cardiac resynchronization therapy.  

PubMed

Although left ventricular (LV) dyssynchrony assessed by ultrasound is emerging as superior to QRS duration in predicting response to cardiac resynchronization therapy (CRT), the role of conventional echocardiographic parameters of dyssynchrony is still debated. Forty-eight patients with heart failure in New York Heart Association classes III to IV, LV ejection fraction < or =35%, and QRS duration > or =120 ms were studied. LV dyssynchrony was evaluated by M-mode as septal-to-posterior wall motion delay and left lateral wall postsystolic displacement (LWPSD). Interventricular dyssynchrony was defined as the difference between the LV and right ventricular preejection periods measured by standard Doppler. Reverse remodeling was defined as an LV end-systolic volume decrease > or =15% after 6 months of CRT. Thirty-one patients (65%) were considered responders to CRT. At baseline responders differed from nonresponders by having less severe New York Heart Association class (p = 0.006), lower percentage of ischemic cause (p = 0.006), longer PR interval (p = 0.013), shorter LV diastolic filling time corrected for heart rate (p = 0.005), and presence of LWPSD (p = 0.003). At multivariate analysis, predictors of CRT response were LWPSD (odds ratio [OR] 1.045, 95% confidence interval [CI] 1.001 to 1.091; p = 0.043), LV diastolic filling time corrected for heart rate (OR 0.855, 95% CI 0.744 to 0.981, p = 0.026), and nonischemic cause (OR 0.109, 95% CI 0.018 to 0.657, p = 0.016). In conclusion, preimplantation assessment of cardiac dyssynchrony based on M-mode LWPSD may predict LV reverse remodeling after CRT, especially in patients with nonischemic cause and shorter diastolic filling time. This suggests the potential role of baseline postsystolic mechanical phenomena in determining response to CRT independently of QRS duration. PMID:17659931

Sassone, Biagio; Capecchi, Alessandro; Boggian, Giulio; Gabrieli, Luca; Saccà, Saverio; Vandelli, Roberto; Petracci, Elisabetta; Mele, Donato

2007-08-01

140

Mechanical discoordination increases continuously after the onset of left bundle branch block despite constant electrical dyssynchrony in a computational model of cardiac electromechanics and growth  

PubMed Central

Aims To test whether a functional growth law leads to asymmetric hypertrophy and associated changes in global and regional cardiac function when integrated with a computational model of left bundle branch block (LBBB). Methods and results In recent studies, we proposed that cardiac myocytes grow longer when a threshold of maximum fibre strain is exceeded and grow thicker when the smallest maximum principal strain in the cellular cross-sectional plane exceeds a threshold. A non-linear cardiovascular model of the beating canine ventricles was combined with the cellular growth law. After inducing LBBB, the ventricles were allowed to adapt in shape over time in response to mechanical stimuli. When subjected to electrical dyssynchrony, the combined model of ventricular electromechanics, haemodynamics, and growth led to asymmetric hypertrophy with a faster increase of wall mass in the left ventricular (LV) free wall (FW) than the septum, increased LV end-diastolic and end-systolic volumes, and decreased LV ejection fraction. Systolic LV pressure decreased during the acute phase of LBBB and increased at later stages. The relative changes of these parameters were similar to those obtained experimentally. Most of the dilation was due to radial and axial fibre growth, and hence altered shape of the LVFW. Conclusion Our previously proposed growth law reproduced measured dyssynchronously induced asymmetric hypertrophy and the associated functional changes, when combined with a computational model of the LBBB heart. The onset of LBBB leads to a step increase in LV mechanical discoordination that continues to increase as the heart remodels despite the constant electrical dyssynchrony. PMID:23104917

Kerckhoffs, Roy C.P.; Omens, Jeffrey H.; McCulloch, Andrew D.

2012-01-01

141

Radionuclide Left Ventricular dV\\/dt for the Assessment of Cardiac Function in Patients with Coronary Disease  

Microsoft Academic Search

To investigatepotential uses of left-ventricular(L\\\\) systolic ejection rate (LV dVldt) in the evaluationof LVfunction, we examined the effect of exercise, angiotensin, and leg raising on LV ejection fraction and LV dV\\/dt in patients with coronary-artery disease. The following observations were made: a) LV ejection fraction and dV\\/dt changed proportionately, but in opposite directions, during supine exercise; b) LV ejectionfraction and

Jesus A. Bianco; Dale G. Makey; Warren K. Laskey; Rex B. Shafer

142

The effects of sodium cromoglycate on lung irritant receptors and left ventricular cardiac receptors in the anaesthetized dog  

PubMed Central

1 The time from the injection of sodium cromoglycate 10 to 50 ?g/kg into a saphenous vein, the cervical carotid arteries, the left ventricle and the aortic arch, to the onset of reflex hypotension has been measured in anaesthetized dogs. The shortest latency was 16.9 s on injection of sodium cromoglycate into the left ventricle. 2 Instillation of 2% lignocaine into the pericardium of an anaesthetized dog blocked the reflex hypotensive response to sodium cromoglycate (10 to 50 ?g/kg i.v.), and also prevented sodium cromoglycate (100 ?g/kg) from reversing reflex bronchoconstriction induced by inhalation of an aerosol of histamine. 3 The effect of sodium cromoglycate (100 ?g/kg i.v.) on resting discharge and histamine-induced discharge (20 ?g/kg i.v.) of five lung irritant receptors in five anaesthetized dogs has been studied. Sodium cromoglycate (100 ?g/kg i.v.) did not affect the resting discharge of these receptors or their ability to respond to histamine. 4 Sodium cromoglycate (100 ?g/kg i.v.) increased the rate of discharge of three receptors found in the endocardium of the left ventricle of the canine heart. A solution of sodium cromoglycate (0.1%) was applied topically to one receptor and its rate of discharge was increased. 5 It is suggested that in the dog, sodium cromoglycate produces reflex hypotension and reverses histamine-induced reflex bronchoconstriction by activating receptors in the left ventricle of the heart. PMID:117865

Dixon, M.; Jackson, D.M.; Richards, I.M.

1979-01-01

143

Cardiac-MRI demonstration of the ligamentum arteriosum in a case of right aortic arch with aberrant left subclavian artery  

PubMed Central

Right-sided aortic arch with aberrant left subclavian artery (RAA/ALSC) is the second most common mediastinal complete vascular ring. Adult presentation of dysphagia lusoria due to a RAA/ALSC is uncommon with fewer than 25 cases reported in the world literature. The left lateral portion of this vascular ring is not a vessel, but an atretic ductus arteriosus, the ligamentum arteriosum, which has been identified in different cases as the major cause of tracheo-esophageal impingement. Surgical division of the ligamentum arteriosum allows the vessels to assume a less constricting pattern decreasing dysphagic symptoms. Clear visualization of the ligamentum arteriosum by diagnostic imaging has not been obtained in previously reported cases. We demonstrated, using magnetic resonance imaging, the location and the complete course of a left-sided ligamentum arteriosum in a patient with adult-onset dysphagia due to a RAA/ALSC with a small Kommerell’s diverticulum, providing, during the same session, a complete assessment of both mediastinal vascular abnormalities and esophageal impingement sites. PMID:22761985

Paparo, Francesco; Bacigalupo, Lorenzo; Melani, Enrico; Rollandi, Gian Andrea; De Caro, Giovanni

2012-01-01

144

Activated cranial cervical cord neurons affect left ventricular infarct size and the potential for sudden cardiac death.  

PubMed

To evaluate whether cervical spinal neurons can influence cardiac indices and myocyte viability in the acutely ischemic heart, the hearts of anesthetized rabbits subjected to 30 min of LAD coronary arterial occlusion (CAO) were studied 3h after reperfusion. Control animals were compared to those exposed to pre-emptive high cervical cord stimulation (SCS; the dorsal aspect of the C1-C2 spinal cord was stimulated electrically at 50 Hz; 0.2 ms; 90% of motor threshold, starting 15 min prior to and continuing throughout CAO). Four groups of animals were so tested: 1) neuroaxis intact; 2) prior cervical vagotomy; 3) prior transection of the dorsal spinal columns at C6; and 4) following pharmacological treatment [muscarinic (atropine) or adrenergic (atenolol, prazosin or yohimbine) receptor blockade]. Infarct size (IS) was measured by tetrazolium, expressed as percentage of risk zone. C1-C2 SCS reduced acute ischemia induced IS by 43%, without changing the incidence of sudden cardiac death (SCD). While SCS-induced reduction in IS was unaffected by vagotomy, it was no longer evident following transection of C6 dorsal columns or atropinization. Beta-adrenoceptor blockade eliminated ischemia induced SCD, while alpha-receptor blockade doubled its incidence. During SCS, myocardial ischemia induced SCD was eliminated following vagotomy while remaining unaffected by atropinization. These data indicate that, in contrast to thoracic spinal neurons, i) cranial cervical spinal neurons affect both adrenergic and cholinergic motor outflows to the heart such that ii) their activation modifies ventricular infarct size and lethal arrhythmogenesis. PMID:22502863

Southerland, E Marie; Gibbons, David D; Smith, S Brooks; Sipe, Adam; Williams, Carole Ann; Beaumont, Eric; Armour, J Andrew; Foreman, Robert D; Ardell, Jeffrey L

2012-07-01

145

Treatment of lone atrial fibrillation: minimally invasive pulmonary vein isolation, partial cardiac denervation and excision of the left atrial appendage  

PubMed Central

Since 1999, my colleagues and I have diligently pursued a minimally invasive surgical, beating-heart, left atrial isolation technique that is offered to patients with lone atrial fibrillation (AF). We began clinical cases in 2003. In 2005, we reported our initial experience with video-assisted bilateral pulmonary vein (PV) isolation and left atrial appendage (LAA) exclusion for the minimally invasive treatment of AF (Wolf technique). From our experience in over 1,000 cases there have been many lessons learned in the evaluation, selection and minimally invasive surgical treatment of patients with lone AF. In our experience we have had zero mortality and no conversions to sternotomy. Recently we reviewed 157 patients who are now 1 to 9 years out from the Wolf technique. The patients’ ages ranged from 15 to 87 years old. The AF-free rate for paroxysmal AF was 92%, for persistent AF 85%, and for long-standing persistent AF 75%. The follow-up included 7-day continuous monitoring. There were no deaths (personal review). The Wolf technique is a safe and effective treatment for selected patients with lone AF. PMID:24516806

2014-01-01

146

Treatment of lone atrial fibrillation: minimally invasive pulmonary vein isolation, partial cardiac denervation and excision of the left atrial appendage.  

PubMed

Since 1999, my colleagues and I have diligently pursued a minimally invasive surgical, beating-heart, left atrial isolation technique that is offered to patients with lone atrial fibrillation (AF). We began clinical cases in 2003. In 2005, we reported our initial experience with video-assisted bilateral pulmonary vein (PV) isolation and left atrial appendage (LAA) exclusion for the minimally invasive treatment of AF (Wolf technique). From our experience in over 1,000 cases there have been many lessons learned in the evaluation, selection and minimally invasive surgical treatment of patients with lone AF. In our experience we have had zero mortality and no conversions to sternotomy. Recently we reviewed 157 patients who are now 1 to 9 years out from the Wolf technique. The patients' ages ranged from 15 to 87 years old. The AF-free rate for paroxysmal AF was 92%, for persistent AF 85%, and for long-standing persistent AF 75%. The follow-up included 7-day continuous monitoring. There were no deaths (personal review). The Wolf technique is a safe and effective treatment for selected patients with lone AF. PMID:24516806

Wolf, Randall K

2014-01-01

147

Utility of Doppler Myocardial Imaging, Cardiac Biomarkers and Clonal Immunoglobulin Genes to Assess Left Ventricular Performance and Stratify Risk Following Peripheral Blood Stem Cell Transplantation in Patients with Systemic Light Chain Amyloidosis (AL)  

PubMed Central

Cardiac dysfunction is a well-recognized complication of light chain amyloidosis (AL). Autologous stem cell transplant (auto-SCT) has emerged as a successful treatment modality for AL patients. In this study, we examined the effect of clonal immunoglobulin light chain genes (VL), which encodes the immunoglobulin light chain protein that ultimately forms amyloid, on cardiac function, in the context of auto-SCT and its impact on overall survival. Longitudinal Doppler myocardial imaging parameters along with cardiac biomarkers were used to assess for cardiac function pre and post auto-SCT. VL gene analysis revealed that V? genes, in particular V?VI, were associated with worse cardiac function parameters than V? genes. Clonal VL genes appeared to have an impact on left ventricular (LV) function post-transplant and also influenced mortality, with specific VL gene families associated with lower survival. Another key predictor of mortality in this report was change in tricuspid regurgitant flow velocity following auto-SCT. Correlations were also observed between systolic strain rate, systolic strain and VL genes associated with amyloid formation. In summary, clonal VL gene usage influences global cardiac function in AL, with patients having V?VI and V?II-III-associated amyloid more severely affected than those having V? or V?I amyloid. Pulsed wave tissue Doppler imaging along with immunoglobulin gene analysis offers novel insights into prediction of mortality and cardiac dysfunction in AL after auto-SCT. PMID:21315556

Bellavia, Diego; Abraham, Roshini S.; Pellikka, Patricia A.; Dispenzieri, Angela; Burnett, John C.; Al-Zahrani, Ghormallah B.; Green, Tammy D.; Manske, Michelle K.; Gertz, Morie A.; Miller, Fletcher A.; Abraham, Theodore P.

2011-01-01

148

Pathological findings in cardiac apex removed during implantation of left ventricular assist devices (LVAD) are non-specific: 13-year-experience at a German Heart Center  

PubMed Central

Background and aim: Ventricular assist devices (VAD) have become an established therapy for patients with end-stage heart failure. The two main reasons for this development are the shortage of appropriate donor organs and the increasing number of patients waiting for heart transplantation (HTX). Furthermore, the enormous advances in the technical equipment and the rising clinical experience have improved the implantation technique, the durability and the long-term patient outcomes. Methods: We reviewed all cases of left ventricular assist device (LVAD) implantation at our Erlangen Heart Center during January 2000-July 2013. The main aim of this study was to analyze the underlying pathology from the cardiac apex removed during the implantation. From all patients, we created a follow-up, analyzed the pathological features with the clinical diagnoses and described the overall outcome. Results: VAD implantation was performed in 266 cases at our center in the last 13 years (2.2% of the total of 12254 cardiac surgical operations in that period). From these patients, 223 underwent LVAD or biventricular (BVAD) implantation; the remaining received a right (RVAD) implantation. The most frequent underlying clinical diagnoses were dilated (n = 84, 37.7%, DCM) or ischemic (n = 61, 27.4%, ICM) cardiomyopathy. The pathological findings in the apex biopsy were generally non-specific and showed variable interstitial myocardial fibrosis with evidence of fibre loss, fatty degeneration and variable irregular atrophy of muscle fibres, consistent with dilated and ischemic cardiomyopathies as the most frequent causes of heart failure in these patients. Only a few cases showed other specific features such as myocarditis and AL-amyloidosis. Conclusions: Pathological findings in cardiac apex removed during LVAD implantation are rather non-specific and they generally reflect the late stage or consequences of chronic myocardial damage in cases of dilated or ischemic cardiomyopathies. Variable patchy chronic inflammatory changes may be observed in cardiomyopathies as a non-specific reaction caused by myocardial fiber damage and should not lead to misinterpretation as evidence of myocarditis or revision of original diagnosis. PMID:25337196

Strecker, Thomas; Rösch, Johannes; Weyand, Michael; Agaimy, Abbas

2014-01-01

149

Impact of epoetin alfa on left ventricular structure, function, and pressure volume relations as assessed by cardiac magnetic resonance: the heart failure preserved ejection fraction (HFPEF) anemia trial.  

PubMed

Anemia, a common comorbidity in older adults with heart failure and a preserved ejection fraction (HFPEF), is associated with worse outcomes. The authors quantified the effect of anemia treatment on left ventricular (LV) structure and function as measured by cardiac magnetic resonance (CMR) imaging. A prospective, randomized single-blind clinical trial (NCT NCT00286182) comparing the safety and efficacy of epoetin alfa vs placebo for 24 weeks in which a subgroup (n=22) had cardiac magnetic resonance imaging (MRI) at baseline and after 3 and 6 months to evaluate changes in cardiac structure and function. Pressure volume (PV) indices were derived from MRI measures of ventricular volume coupled with sphygmomanometer-measured pressure and Doppler estimates of filling pressure. The end-systolic and end-diastolic PV relations and the area between them as a function of end-diastolic pressure, the isovolumic PV area (PVAiso), were calculated. Patients (75±10 years, 64% women) with HFPEF (EF=63%±15%) with an average hemoglobin of 10.3±1.1 gm/dL were treated with epoetin alfa using a dose-adjusted algorithm that increased hemoglobin compared with placebo (P<.0001). As compared with baseline, there were no significant changes in end-diastolic (-7±8 mL vs -3±8 mL, P=.81) or end-systolic (-0.4±2 mL vs -0.7±5 mL, P=.96) volumes at 6-month follow-up between epoetin alfa compared with placebo. LV function as measured based on EF (-1.5%±1.6% vs -2.6%±3.3%, P=.91) and pressure volume indices (PVAiso-EDP at 30 mm Hg, -5071±4308 vs -1662±4140, P=.58) did not differ between epoetin alfa and placebo. Administration of epoetin alfa to older adult patients with HFPEF resulted in a significant increase in hemoglobin, without evident change in LV structure, function, or pressure volume relationships as measured quantitatively using CMR imaging. PMID:23517485

Green, Philip; Babu, Benson A; Teruya, Sergio; Helmke, Stephen; Prince, Martin; Maurer, Mathew S

2013-01-01

150

Radionuclide left ventricular dV/dt for the assessment of cardiac function in patients with coronary disease.  

PubMed

To investigate potential uses of left-ventricular (LV) systolic ejection rate (LV dV/dt) in the evaluation of LV function, we examined the effect of exercise, angiotensin, and leg raising on LV ejection fraction and LV dV/dt in patients with coronary-artery disease. The following observations were made: a) LV ejection fraction and dV/dt changed proportionately, but in opposite directions, during supine exercise; b) LV ejection fraction and dV/dt decreased to a similar extent during angiotensin infusions; and c) LV ejection fraction and dV/dt were unchanged by leg raising. The changes in peak and mean LV dV/dt were similar. Regardless of the physiologic state, peak LV dV/dt occurred during the first third of systole. These data imply that in this population there were no specific advantages of LV dV/dt over LV ejection fraction in the evaluation of LV performance. PMID:430171

Bianco, J A; Makey, D G; Laskey, W K; Shafer, R B

1979-01-01

151

Serum High-Sensitivity Cardiac Troponin T Is a Significant Biomarker of Left-Ventricular Diastolic Dysfunction in Subjects with Non-Diabetic Chronic Kidney Disease  

PubMed Central

Background Chronic kidney disease (CKD) is associated with left-ventricular (LV) diastolic dysfunction (LVDD) which progresses to diastolic heart failure. However, biomarkers predicting LVDD in patients with CKD are largely unknown. Methods In 93 patients with non-diabetic CKD, the relationships among echocardiography, high-sensitivity cardiac troponin T (hs-cTnT), B-type natriuretic peptide (BNP), and renal function were evaluated. LV mass index, peak early diastolic mitral filling velocity (E), peak early diastolic mitral annular velocity (E?), and E/E? were recorded. Results The E? values were significantly decreased and E/E?, BNP, and hs-cTnT increased with increasing CKD stage. The CKD patients with LVDD with E? <5 cm/s had a significantly higher hs-cTnT level as well as a significantly higher BNP level compared to those with E? ?5 cm/s. The area under the receiver-operating characteristic curve for hs-cTnT and BNP to detect E? <5 cm/s was 0.880 (p = 0.0101) and 0.741 (p = 0.0570), respectively. In multivariate analysis, hs-cTnT and albuminuria were significantly associated with E?, and estimated glomerular filtration rate with the hs-cTnT level, after adjusting for age, cause of CKD, and other parameters. Conclusions These data suggest that hs-cTnT may be a useful biomarker of LVDD in non- diabetic CKD patients. PMID:22470390

Kitagawa, Masashi; Sugiyama, Hitoshi; Morinaga, Hiroshi; Inoue, Tatsuyuki; Takiue, Keiichi; Kikumoto, Yoko; Uchida, Haruhito Adam; Kitamura, Shinji; Maeshima, Yohei; Toh, Norihisa; Nakamura, Kazufumi; Ito, Hiroshi; Makino, Hirofumi

2011-01-01

152

Simulation of Left Atrial Function Using a Multi-Scale Model of the Cardiovascular System  

PubMed Central

During a full cardiac cycle, the left atrium successively behaves as a reservoir, a conduit and a pump. This complex behavior makes it unrealistic to apply the time-varying elastance theory to characterize the left atrium, first, because this theory has known limitations, and second, because it is still uncertain whether the load independence hypothesis holds. In this study, we aim to bypass this uncertainty by relying on another kind of mathematical model of the cardiac chambers. In the present work, we describe both the left atrium and the left ventricle with a multi-scale model. The multi-scale property of this model comes from the fact that pressure inside a cardiac chamber is derived from a model of the sarcomere behavior. Macroscopic model parameters are identified from reference dog hemodynamic data. The multi-scale model of the cardiovascular system including the left atrium is then simulated to show that the physiological roles of the left atrium are correctly reproduced. This include a biphasic pressure wave and an eight-shaped pressure-volume loop. We also test the validity of our model in non basal conditions by reproducing a preload reduction experiment by inferior vena cava occlusion with the model. We compute the variation of eight indices before and after this experiment and obtain the same variation as experimentally observed for seven out of the eight indices. In summary, the multi-scale mathematical model presented in this work is able to correctly account for the three roles of the left atrium and also exhibits a realistic left atrial pressure-volume loop. Furthermore, the model has been previously presented and validated for the left ventricle. This makes it a proper alternative to the time-varying elastance theory if the focus is set on precisely representing the left atrial and left ventricular behaviors. PMID:23755183

Pironet, Antoine; Dauby, Pierre C.; Paeme, Sabine; Kosta, Sarah; Chase, J. Geoffrey; Desaive, Thomas

2013-01-01

153

Automatic view planning for cardiac MRI acquisition.  

PubMed

Conventional cardiac MRI acquisition involves a multi-step approach, requiring a few double-oblique localizers in order to locate the heart and prescribe long- and short-axis views of the heart. This approach is operator-dependent and time-consuming. We propose a new approach to automating and accelerating the acquisition process to improve the clinical workflow. We capture a highly accelerated static 3D full-chest volume through parallel imaging within one breath-hold. The left ventricle is localized and segmented, including left ventricle outflow tract. A number of cardiac landmarks are then detected to anchor the cardiac chambers and calculate standard 2-, 3-, and 4-chamber long-axis views along with a short-axis stack. Learning-based algorithms are applied to anatomy segmentation and anchor detection. The proposed algorithm is evaluated on 173 localizer acquisitions. The entire view planning is fully automatic and takes less than 10 seconds in our experiments. PMID:22003734

Lu, Xiaoguang; Jolly, Marie-Pierre; Georgescu, Bogdan; Haye, Carmel; Speier, Peter; Schmidt, Michaela; Bi, Xiaoming; Kroeker, Randall; Comaniciu, Dorin; Kellman, Peter; Mueller, Edgar; Guehring, Jens

2011-01-01

154

Higher sympathetic nerve activity during ventricular (VVI) than during dual-chamber (DDD) pacing  

NASA Technical Reports Server (NTRS)

OBJECTIVES: We determined the short-term effects of single-chamber ventricular pacing and dual-chamber atrioventricular (AV) pacing on directly measured sympathetic nerve activity. BACKGROUND: Dual-chamber AV cardiac pacing results in greater cardiac output and lower systemic vascular resistance than does single-chamber ventricular pacing. However, it is unclear whether these hemodynamic advantages result in less sympathetic nervous system outflow. METHODS: In 13 patients with a dual-chamber pacemaker, we recorded the electrocardiogram, noninvasive arterial pressure (Finapres), respiration and muscle sympathetic nerve activity (microneurography) during 3 min of underlying basal heart rate and 3 min of ventricular and AV pacing at rates of 60 and 100 beats/min. RESULTS: Arterial pressure was lowest and muscle sympathetic nerve activity was highest at the underlying basal heart rate. Arterial pressure increased with cardiac pacing and was greater with AV than with ventricular pacing (change in mean blood pressure +/- SE: 10 +/- 3 vs. 2 +/- 2 mm Hg at 60 beats/min; 21 +/- 5 vs. 14 +/- 2 mm Hg at 100 beats/min; p < 0.05). Sympathetic nerve activity decreased with cardiac pacing and the decline was greater with AV than with ventricular pacing (60 beats/min -40 +/- 11% vs. -17 +/- 7%; 100 beats/min -60 +/- 9% vs. -48 +/- 10%; p < 0.05). Although most patients showed a strong inverse relation between arterial pressure and muscle sympathetic nerve activity, three patients with severe left ventricular dysfunction (ejection fraction < or = 30%) showed no relation between arterial pressure and sympathetic activity. CONCLUSIONS: Short-term AV pacing results in lower sympathetic nerve activity and higher arterial pressure than does ventricular pacing, indicating that cardiac pacing mode may influence sympathetic outflow simply through arterial baroreflex mechanisms. We speculate that the greater incidence of adverse outcomes in patients treated with single-chamber ventricular rather than dual-chamber pacing may be due in part to increased sympathetic nervous outflow.

Taylor, J. A.; Morillo, C. A.; Eckberg, D. L.; Ellenbogen, K. A.

1996-01-01

155

Hospitalization rates and associated cost analysis of cardiac resynchronization therapy with an implantable defibrillator and quadripolar vs. bipolar left ventricular leads: a comparative effectiveness study  

PubMed Central

Aims This study compares, from a prospective, observational, non-randomized registry, the post-implant hospitalization rates and associated healthcare resource utilization of cardiac resynchronization therapy-defibrillator (CRT-D) patients with quadripolar (QUAD) vs. bipolar (BIP) left ventricular (LV) leads. Methods and results Between January 2009 and December 2012, 193 consecutive patients receiving de novo CRT-D implants with either a QUAD (n = 116) or a BIP (n = 77) LV lead were enrolled at implant and followed until July 2013 at a single-centre, university hospital. Post-implant hospitalizations related to heart failure (HF) or LV lead surgical revision and associated payer costs were identified using ICD-9-CM diagnosis and procedure codes. Italian national reimbursement rates were determined. Propensity scores were estimated using a logistic regression model based upon 11 pre-implant baseline characteristics and were used to derive a 1 : 1 matched cohort of QUAD (n = 77) and BIP (n = 77) patients. Hospitalization rates for the two groups were compared using negative binomial regression and associated payer costs were compared using non-parametric bootstrapping (×10 000) and one-sided hypothesis test. Hospitalization rates of the QUAD group [0.15/ patient (pt)-year] were lower than those of the BIP group (0.32/ pt-year); the incidence rate ratio was 0.46, P = 0.04. The hospitalization costs for the QUAD group (434 ± 128 €/pt-year) were lower than those for the BIP group (1136 ± 362 €/pt-year). The average difference was 718 €/pt-year, P = 0.016. Conclusions In this comparative effectiveness assessment of well-matched groups of CRT-D patients with quadripolar and bipolar LV leads, QUAD patients experienced a lower rate of hospitalizations for HF and LV lead surgical revision, and a lower cost burden. This has important implications for LV pacing lead choice. PMID:25371428

Forleo, Giovanni B.; Di Biase, Luigi; Bharmi, Rupinder; Dalal, Nirav; Panattoni, Germana; Pollastrelli, Annalisa; Tesauro, Manfredi; Santini, Luca; Natale, Andrea; Romeo, Francesco

2015-01-01

156

Pressure overload-induced mild cardiac hypertrophy reduces left ventricular transmural differences in mitochondrial respiratory chain activity and increases oxidative stress  

PubMed Central

Objective: Increased mechanical stress and contractility characterizes normal left ventricular (LV) subendocardium (Endo) but whether Endo mitochondrial respiratory chain complex activities is reduced as compared to subepicardium (Epi) and whether pressure overload-induced LV hypertrophy (LVH) might modulate transmural gradients through increased reactive oxygen species (ROS) production is unknown. Methods: LVH was induced by 6 weeks abdominal aortic banding and cardiac structure and function were determined with echocardiography and catheterization in sham-operated and LVH rats (n = 10 for each group). Mitochondrial respiration rates, coupling, content and ROS production were measured in LV Endo and Epi, using saponin-permeabilized fibers, Amplex Red fluorescence and citrate synthase activity. Results: In sham, a transmural respiratory gradient was observed with decreases in endo maximal oxidative capacity (?36.7%, P < 0.01) and complex IV activity (?57.4%, P < 0.05). Mitochondrial hydrogen peroxide (H2O2) production was similar in both LV layers. Aortic banding induced mild LVH (+31.7% LV mass), associated with normal LV fractional shortening and end diastolic pressure. LVH reduced maximal oxidative capacity (?23.6 and ?33.3%), increased mitochondrial H2O2 production (+86.9 and +73.1%), free radical leak (+27.2% and +36.3%) and citrate synthase activity (+27.2% and +36.3%) in Endo and Epi, respectively. Transmural mitochondrial respiratory chain complex IV activity was reduced in LVH (?57.4 vs. ?12.2%; P = 0.02). Conclusions: Endo mitochondrial respiratory chain complexes activities are reduced compared to LV Epi. Mild LVH impairs mitochondrial oxidative capacity, increases oxidative stress and reduces transmural complex IV activity. Further studies will be helpful to determine whether reduced LV transmural gradient in mitochondrial respiration might be a new marker of a transition from uncomplicated toward complicated LVH. PMID:22934079

Kindo, Michel; Gerelli, Sébastien; Bouitbir, Jamal; Charles, Anne-Laure; Zoll, Joffrey; Hoang Minh, Tam; Monassier, Laurent; Favret, Fabrice; Piquard, François; Geny, Bernard

2012-01-01

157

High-amplitude left ventricular pacing in cardiac resynchronization therapy: an alternative way to increase response rate in non-responders  

PubMed Central

Purpose This study compared patients who underwent cardiac resynchronization therapy (CRT) by high-amplitude left ventricular (LV) pacing with those who underwent CRT by standard LV pacing. Methods We included 32 CRT patients with ejection fraction (EF) ?35%, QRS time ?120 ms, and New York Heart Association (NYHA) class III/IV symptoms of heart failure despite optimal medical treatment. These patients were evaluated clinically and echocardiographically before, three and six months after CRT. At the 3rd month, the LV pulse amplitude value was set high at 5 volt for 16 patients [high-amplitude Group (HAG)], while for the other 16 patients, it was reduced to at least twice the threshold value at ?2.5 volt [low-amplitude group (LAG)]. Results Clinical and echocardiographic response rates of HAG and LAG after CRT were similar in the 3rd and 6th month. In both groups, increase in LVEF and decrease in LV ESV in the 3rd and 6th month were statistically significant compared to those before CRT, and NYHA class and end-diastolic volume (EDV) was significantly reduced in the 6th month compared to those before CRT. However, NHYA class and EDV continued to reduce significantly in HAG from the 3rd to the 6th month (P<0.05), while the decrease in LAG was not significant (P>0.05). The rate of mitral regurgitation (MR) was reduced significantly in HAG in the 6th month compared to that before CRT, while the decrease in LAG was not significant (P<0.05; P>0.05 respectively). Conclusions CRT by high-amplitude LV pacing was more effective according to clinical and echocardiographic evaluations. It should be considered as an alternative in non-responsive patients. PMID:24255779

Ak?n, Filiz; Demircan, Sabri; Soylu, Korhan; Erbay, Alir?za; Yuksel, Serkan; Meric, Murat; Gulel, Okan; Sahin, Mahmut; Y?lmaz, Ozcan

2013-01-01

158

Short-axis epicardial volume change is a measure of cardiac left ventricular short-axis function, which is independent of myocardial wall thickness.  

PubMed

Fractional shortening (FS) by echocardiography is considered to represent the short-axis contribution to the stroke volume (SV), also called short-axis function. However, FS is mathematically coupled to the amount of myocardium, since it rearranges during atrioventricular plane displacement (AVPD). The SV is the sum of the volumes generated by 1) reduction in outer volume of the heart, and 2) inner AVPD. The long-axis contribution to the SV is generated by AVPD, and thus the short-axis contribution is the remaining outer volume change of the heart, which should be unrelated to myocardial wall thickness. We hypothesized that both endocardial and midwall shortening indexed to SV are dependent on myocardial wall thickness, whereas epicardial volume change (EVC) indexed to SV is not. Twelve healthy volunteers (normals), 12 athletes, and 12 patients with dilated cardiomyopathy (ejection fraction < 30%) underwent cine cardiac magnetic resonance imaging. Left ventricular long-axis function was measured as the portion of the SV, in milliliters, generated by AVPD. EVC was defined as SV minus long-axis function. Endocardial and midwall shortening were measured in a midventricular short-axis slice. Endocardial shortening/SV and midwall shortening/SV both varied in relation to end-diastolic myocardial wall thickness (R(2) = 0.16, P = 0.008 and R(2) = 0.14, P = 0.012, respectively), whereas EVC/SV did not (R(2) = 0.00, P = 0.37). FS is dependent on myocardial wall thickness, whereas EVC is not and therefore represents true short-axis function. This is not surprising considering that FS is mainly caused by rearrangement of myocardium secondary to long-axis function. FS is therefore not synonymous with short-axis function. PMID:19933422

Ugander, Martin; Carlsson, Marcus; Arheden, Håkan

2010-02-01

159

Adult teleost heart expresses two distinct troponin C paralogs: cardiac TnC and a novel and teleost-specific ssTnC in a chamber- and temperature-dependent manner.  

PubMed

The teleost-specific whole genome duplication created multiple copies of genes allowing for subfunctionalization of isoforms. In this study, we show that the teleost cardiac Ca2+-binding troponin C (TnC) is the product of two distinct genes: cardiac TnC (cTnC, TnnC1a) and a fish-specific slow skeletal TnC (ssTnC, TnnC1b). The ssTnC gene is novel to teleosts as mammals have a single gene commonly referred as cTnC but which is also expressed in slow skeletal muscle. In teleosts, the data strongly indicate that these are two TnC genes are different paralogs. Because we determined that ssTnC exists across many teleosts but not in basal ray-finned fish (e.g., bichir), we propose that these paralogs are the result of an ancestral tandem gene duplication persisting only in teleosts. Quantification of mRNA levels was used to demonstrate distinct expression localization patterns of the paralogs within the chambers of the heart. In the adult zebrafish acclimated at 28°C, ssTnC mRNA levels are twofold greater than cTnC mRNA levels in the atrium, whereas cTnC mRNA was almost exclusively expressed in the ventricle. Meanwhile, rainbow trout acclimated at 5°C showed cTnC mRNA levels in both chambers significantly greater than ssTnC. Distinct responses to temperature acclimation were also quantified in both adult zebrafish and rainbow trout, with mRNA in both chambers shifting to express higher levels of cTnC in 18°C acclimated zebrafish and 5°C acclimated trout. Possible subfunctionalization of TnC isoforms may provide insight into how teleosts achieve physiological versatility in chamber-specific contractile properties. PMID:23881286

Genge, Christine E; Davidson, William S; Tibbits, Glen F

2013-09-16

160

Flow chamber  

DOEpatents

A flow chamber having a vacuum chamber and a specimen chamber. The specimen chamber may have an opening through which a fluid may be introduced and an opening through which the fluid may exit. The vacuum chamber may have an opening through which contents of the vacuum chamber may be evacuated. A portion of the flow chamber may be flexible, and a vacuum may be used to hold the components of the flow chamber together.

Morozov, Victor (Manassas, VA)

2011-01-18

161

Late Gadolinium Enhancement in Cardiac MRI in Patients with Severe Aortic Stenosis and Preserved Left Ventricular Systolic Function Is Related to Attenuated Improvement of Left Ventricular Geometry and Filling Pressure after Aortic Valve Replacement  

PubMed Central

Background and Objectives We investigated echocardiographic predictors: left ventricular (LV) geometric changes following aortic valve replacement (AVR) according to the late gadolinium enhancement (LGE) on cardiac magnetic resonance imaging (CMR) in patients with severe aortic stenosis (AS) and preserved LV systolic function. Subjects and Methods We analyzed 41 patients (24 males, 63.1±8.7 years) with preserved LV systolic function who were scheduled to undergo AVR for severe AS. All patients were examined with transthoracic echocardiography (TTE), CMR before and after AVR (in the hospital) and serial TTEs (at 6 and 12 months) were repeated. Results The group with LGE (LGE+) showed greater wall thickness (septum, 14.3±2.6 mm vs. 11.5±2.0 mm, p=0.001, posterior; 14.3±2.5 mm vs. 11.4±1.6 mm, p<0.001), lower tissue Doppler image (TDIS', 4.4±1.4 cm/s vs. 5.5±1.2 cm/s, p=0.021; TDI E', 3.2±0.9 cm/s vs. 4.8±1.4 cm/s, p=0.002), and greater E/e' (21.8±10.3 vs. 15.4±6.3, p=0.066) than those without LGE (LGE-). Multivariate analysis show that TDI e' (odds ratio=0.078, 95% confidence interval=0.007-0.888, p=0.040) was an independent determinant of LGE+. In an analysis of the 6- and 12-month follow-up compared with pre-AVR, LGE- showed decreased LV end-diastolic diameter (48.3±5.0 mm vs. 45.8±3.6 mm, p=0.027; 48.3±5.0 mm vs. 46.5±3.4 mm, p=0.019). Moreover, E/e' (at 12 months) showed further improved LV filling pressure (16.0±6.6 vs. 12.3±4.3, p=0.001) compared with pre-AVR. However, LGE+ showed no significant improvement. Conclusion The absence of LGE is associated with favorable improvements in LV geometry and filling pressure. TDI E' is an independent determinant of LGE in patients with severe AS and preserved LV systolic function. PMID:25278984

Park, Junbeom; Choi, Jung-Ho; Yang, Pil-Sung; Lee, Sang-Eun; Heo, Ran; Shin, Sanghoon; Cho, In-Jeong; Kim, Young-Jin; Shim, Chi Young; Hong, Geu-Ru; Chung, Namsik

2014-01-01

162

Gated F-18 FDG PET for Assessment of Left Ventricular Volumes and Ejection Fraction Using QGS and 4D-MSPECT in Patients with Heart Failure: A Comparison with Cardiac MRI  

PubMed Central

Purpose Ventricular function is a powerful predictor of survival in patients with heart failure (HF). However, studies characterizing gated F-18 FDG PET for the assessment of the cardiac function are rare. The aim of this study was to prospectively compare gated F-18 FDG PET and cardiac MRI for the assessment of ventricular volume and ejection fraction (EF) in patients with HF. Methods Eighty-nine patients with diagnosed HF who underwent both gated F-18 FDG PET/CT and cardiac MRI within 3 days were included in the analysis. Left ventricular (LV) end-diastolic volume (EDV), end-systolic volume (ESV), and EF were obtained from gated F-18 FDG PET/CT using the Quantitative Gated SPECT (QGS) and 4D-MSPECT software. Results LV EDV and LV ESV measured by QGS were significantly lower than those measured by cardiac MRI (both P<0.0001). In contrast, the corresponding values for LV EDV for 4D-MSPECT were comparable, and LV ESV was underestimated with borderline significance compared with cardiac MRI (P?=?0.047). LV EF measured by QGS and cardiac MRI showed no significant differences, whereas the corresponding values for 4D-MSPECT were lower than for cardiac MRI (P<0.0001). The correlations of LV EDV, LV ESV, and LV EF between gated F-18 FDG PET/CT and cardiac MRI were excellent for both QGS (r?=?0.92, 0.92, and 0.76, respectively) and 4D-MSPECT (r?=?0.93, 0.94, and 0.75, respectively). However, Bland-Altman analysis revealed a significant systemic error, where LV EDV (?27.9±37.0 mL) and ESV (?18.6±33.8 mL) were underestimated by QGS. Conclusion Despite the observation that gated F-18 FDG PET/CT were well correlated with cardiac MRI for assessing LV function, variation was observed between the two imaging modalities, and so these imaging techniques should not be used interchangeably. PMID:24404123

Zhao, Shi-Hua; He, Zuo-Xiang; Wang, Dao-Yu; Guo, Feng; Fang, Wei; Yang, Min-Fu

2014-01-01

163

Effects of occlusion of the left anterior descending coronary artery during angioplasty on right-sided cardiac pressures and electrocardiographic changes.  

PubMed

Controversy persists regarding the presence and extent of right ventricular involvement with acute anterior injury. Also unclear are the incidence and significance of ST elevations in the right-sided leads in acute left anterior descending artery occlusion. Baseline and coronary occlusion hemodynamics and 15-lead electrocardiograms (addition of RV3 through RV5) were recorded in 42 patients during 32 left anterior descending and 13 right coronary artery angioplasties. The right coronary and left anterior descending artery angioplasties had similar baseline right and left ventricular hemodynamics, as well as identical right atrial to pulmonary wedge pressure ratios (0.51 right coronary vs 0.51 left anterior descending). Whereas the right coronary and left anterior descending occlusions produced similar elevations in right ventricular filling pressures, the left anterior descending occlusions produced greater elevations in left ventricular filling pressures. The right atrial to pulmonary wedge ratio increased with right coronary occlusions, but was unchanged with left anterior descending occlusions (0.79 right vs 0.46 left, p less than or equal to 0.0001). Presence of right-lead ST elevations in 10 left anterior descending occlusions did not con-note increased right ventricular filling pressures, but did suggest increased left ventricular ischemia and dysfunction. In conclusion, right ventricular dysfunction, as manifested by increased filling pressures, is seen with both right coronary and left anterior descending occlusions. Although it is the predominant abnormality in right coronary occlusions, in left anterior descending occlusions it is proportional to left ventricular dysfunction. ST elevations in a right lead with left anterior descending occlusions do not constitute a marker for increased right ventricular dysfunction. PMID:2528901

Charlap, S; Schulhoff, N; Mylavarapu, S; Greengart, A; Gelbfish, J; Budzilowicz, L; Hollander, G; Lichstein, E; Shani, J

1989-09-15

164

Determinants of discrepancies in detection and comparison of the prognostic significance of left ventricular hypertrophy by electrocardiogram and cardiac magnetic resonance imaging.  

PubMed

Despite the low sensitivity of the electrocardiogram (ECG) in detecting left ventricular hypertrophy (LVH), ECG-LVH is known to be a strong predictor of cardiovascular risk. Understanding reasons for the discrepancies in detection of LVH by ECG versus imaging could help improve the diagnostic ability of ECG. We examined factors associated with false-positive and false-negative ECG-LVH, using cardiac magnetic resonance imaging (MRI) as the gold standard. We also compared the prognostic significance of ECG-LVH and MRI-LVH as predictors of cardiovascular events. This analysis included 4,748 participants (mean age 61.9 years, 53.5% females, 61.7% nonwhites). Logistic regression with stepwise selection was used to identify factors associated with false-positive (n = 208) and false-negative (n = 387), compared with true-positive (n = 208) and true-negative (n = 4,041) ECG-LVH, respectively. A false-negative ECG-LVH status was associated with increased odds of Hispanic race/ethnicity, current smoking, hypertension, increased systolic blood pressure, prolongation of QRS duration, and higher body mass index and with lower odds of increased ejection fraction (model-generalized R(2) = 0.20). A false-positive ECG-LVH status was associated with lower odds of black race, Hispanic race/ethnicity, minor ST-T abnormalities, increased systolic blood pressure, and presence of any major electrocardiographic abnormalities (model-generalized R(2) = 0.29). Both ECG-LVH and MRI-LVH were associated with an increased risk of cardiovascular disease events (hazard ratio 1.51, 95% confidence interval 1.03 to 2.20 and hazard ratio 1.81, 95% confidence interval 1.33 to 2.46, respectively). In conclusion, discrepancy in LVH detection by ECG and MRI can be relatively improved by considering certain participant characteristics. Discrepancy in diagnostic performance, yet agreement on predictive ability, suggests that LVH by ECG and LVH by imaging are likely to be two distinct but somehow related phenotypes. PMID:25542394

Bacharova, Ljuba; Chen, Haiying; Estes, E Harvey; Mateasik, Anton; Bluemke, David A; Lima, Joao A C; Burke, Gregory L; Soliman, Elsayed Z

2015-02-15

165

Vector Selection of a Quadripolar Left Ventricular Pacing Lead Affects Acute Hemodynamic Response to Cardiac Resynchronization Therapy: A Randomized Cross-Over Trial  

PubMed Central

Background A suboptimal left ventricular (LV) pacing site may account for non-responsiveness of patients to cardiac resynchronization therapy (CRT). The vector selection of a novel quadripolar LV pacing lead, which was mainly developed to overcome technical issues with stimulation thresholds and phrenic nerve capture, may affect hemodynamic response, and was therefore assessed in this study. (German Clinical Trials Register DRKS00000573). Methods and Results Hemodynamic effects of a total of 145 LVPCs (9.1 per patient) of CRT devices with a quadripolar LV lead (Quartet™, St. Jude Medical) were assessed in 16/20 consecutive patients by invasive measurement of LV+dP/dtmax at an invasively optimized AV-interval in random order. Optimal (worst) LVPCs per patient were identified as those with maximal (minimal) %change in LV+dP/dtmax (%?LV+dP/dtmax) as compared to a preceding baseline. LV+dP/dtmax significantly increased in all 145 LVPCs (p<0.0001 compared to baseline) with significant intraindividual differences between LVPCs (p<0.0001). Overall, CRT acutely augmented %?LV+dP/dtmax by 31.3% (95% CI 24%–39%) in the optimal, by 21.3% (95% CI: 15%–27%) in the worst and by 28.2% (95% CI: 21%–36%) in a default distal LVPC. This resulted in an absolute additional acute increase in %?LV+dP/dtmax of 10.0% (95% CI: 7%–13%) of the optimal when compared to the worst (p<0.0001), and of 3.1% (95% CI: 1%–5%) of the optimal when compared to the default distal LVPC (p<0.001). Optimal LVPCs were not programmable with a standard bipolar lead in 44% (7/16) of patients. Conclusion The pacing configuration of a quadripolar LV lead determinates acute hemodynamic response. Pacing in the individually optimized configuration gives rise to an additional absolute 10% increase in %?LV+dP/dtmax when comparing optimal and worst vectors. PMID:23826245

Asbach, Stefan; Hartmann, Maximilian; Wengenmayer, Tobias; Graf, Erika; Bode, Christoph; Biermann, Juergen

2013-01-01

166

Registration-based segmentation of murine 4D cardiac micro-CT data using symmetric normalization  

PubMed Central

Micro-CT can play an important role in preclinical studies of cardiovascular disease because of its high spatial and temporal resolution. Quantitative analysis of 4D cardiac images requires segmentation of the cardiac chambers at each time point, an extremely time consuming process if done manually. To improve throughput this study proposes a pipeline for registration-based segmentation and functional analysis of 4D cardiac micro-CT data in the mouse. Following optimization and validation using simulations, the pipeline was applied to in vivo cardiac micro-CT data corresponding to 10 cardiac phases acquired in C57BL/6 mice (n = 5). After edge-preserving smoothing with a novel adaptation of 4D bilateral filtration, one phase within each cardiac sequence was manually segmented. Deformable registration was used to propagate these labels to all other cardiac phases for segmentation. The volumes of each cardiac chamber were calculated and used to derive stroke volume, ejection fraction, cardiac output, and cardiac index. Dice coefficients and volume accuracies were used to compare manual segmentations of two additional phases with their corresponding propagated labels. Both measures were, on average, >0.90 for the left ventricle and >0.80 for the myocardium, the right ventricle, and the right atrium, consistent with trends in inter- and intra-segmenter variability. Segmentation of the left atrium was less reliable. On average, the functional metrics of interest were underestimated by 6.76% or more due to systematic label propagation errors around atrioventricular valves; however, execution of the pipeline was 80% faster than performing analogous manual segmentation of each phase. PMID:22971564

Clark, Darin; Badea, Alexandra; Liu, Yilin; Johnson, G. Allan; Badea, Cristian T.

2013-01-01

167

Large congenital coronary arteriovenous fistula between the left main coronary artery and right superior vena cava, associated with aneurysmal dilatation of the left main coronary artery: rare case report.  

PubMed

Coronary arteriovenous fistula is an uncommon clinical entity. The right coronary artery is the most common site of origin, and the fistula commonly drains into the right-sided cardiac chambers. Very rarely it can arise from the left main coronary artery, and fistulas draining into the superior vena cavity are extremely rare. We report a 12-year-old asymptomatic boy with a large coronary arteriovenous fistula between the left main coronary artery and superior vena cava, with aneurysmal dilatation of the left main coronary artery. As the fistula was very large and to prevent its complications, it was planned to close the fistula percutaneously. PMID:25022527

Chandra, Naveen; Sarkar, Achyut; Pande, Arindam

2015-01-01

168

Repeated Aborted Sudden Cardiac Death with Long QT Syndrome in a Patient with Anomalous Origin of the Right Coronary Artery from the Left Coronary Cusp  

PubMed Central

A 15-year-old female with a prior history of aborted cardiac death and surgical correction of anomalous origin of the right coronary artery (RCA) presented with polymorphic ventricular tachycardia. Her electrocardiogram after defibrillation was suggestive of congenital long QT syndrome (LQTS). The patient was treated with a ?-blocker and remained free from ventricular arrhythmia during the follow-up of more than 6 months. Here, we present the case of a young female with repeated aborted cardiac death accompanied by anomalous origin of the RCA and congenital LQTS for the first time. PMID:24385995

Park, Yae Min; Kim, Su Ji; Park, Chul-Hyun; Kang, Woong Chol; Shin, Mi-Seung; Koh, Kwang Kon

2013-01-01

169

Chapter 2 Background and Method Overview The cardiac left ventricle is one of the most crucial and thoroughly studied structures in the  

E-print Network

) ultrasound to measure geometric properties of the beating heart is therefore particularly exciting ultrasound to other imaging modalities. Given an RT3D image of the heart, analytical techniques chapters. 2A. Imaging of Cardiac Anatomy and Function RV and LV Anatomy and Function The primary function

Stetten, George

170

Action potential morphology of human induced pluripotent stem cell-derived cardiomyocytes does not predict cardiac chamber specificity and is dependent on cell density.  

PubMed

Previous studies investigating human induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) have proposed the distinction of heart chamber-specific (atrial, ventricular, pacemaker) electrophysiological phenotypes based on action potential (AP) morphology. This suggestion has been based on data acquired using techniques that allow measurements from only a small number of cells and at low seeding densities. It has also been observed that density of culture affects the properties of iPSC-CMs. Here we systematically analyze AP morphology from iPSC-CMs at two seeding densities: 60,000 cells/well (confluent monolayer) and 15,000 cells/well (sparsely-seeded) using a noninvasive optical method. The confluent cells (n = 360) demonstrate a series of AP morphologies on a normally distributed spectrum with no evidence for specific subpopulations. The AP morphologies of sparsely seeded cells (n = 32) displayed a significantly different distribution, but even in this case there is no clear evidence of chamber-specificity. Reduction in gap junction conductance using carbenoxolone only minimally affected APD distribution in confluent cells. These data suggest that iPSC-CMs possess a sui generis AP morphology, and when observed in different seeding densities may encompass any shape including those resembling chamber-specific subtypes. These results may be explained by different functional maturation due to culture conditions. PMID:25564842

Du, David T M; Hellen, Nicola; Kane, Christopher; Terracciano, Cesare M N

2015-01-01

171

Cardiac function monitoring system  

Microsoft Academic Search

An IBM-PC controlled system has been developed to evaluate the cardiac function in the catheterization room. The system uses a multielectrode impedancimetric catheter to compute the instantaneous left intraventricular heart volume, through specially developed algorithms and calibration procedures, and a catheter tip micromanometer to measure the instantaneous left intraventricular pressure. With these two variables, and after a preload maneuver, the

J. C. Spinelli; M. C. Herrera

1988-01-01

172

A Rare Case of Left Ventricular Intramural Hemangioma Diagnosed Using 1.5-T Cardiac MRI with Histopathological Correlation and Successfully Treated by Surgery  

SciTech Connect

Hemangiomas are vascular tumors composed of blood vessels, frequently localized in the skin and subcutaneous muscles; their localization in the heart is exceptional. The most common localizations are the lateral walls of the left ventricle, the anterior wall, and the septum. Mostly, these tumors grow intracavitarily, rarely intramurally. We describe a singular case of left ventricular intramural hemangioma, detected and diagnosed using newer magnetic resonance imaging (MRI) modalities, confirmed by histopathological results, and treated successfully by surgery.

Marrone, Gianluca, E-mail: gmarrone@ismett.ed [Mediterranean Institute of Transplantation and High Specialization Therapy (ISMETT), Diagnostic and Interventional Radiology (Italy); Sciacca, Sergio, E-mail: ssciacca@ismett.edu; D'Ancona, Giuseppe, E-mail: gdancona@ismett.edu; Pilato, Michele, E-mail: mpilato@ismett.ed [Mediterranean Institute of Transplantation and High Specialization Therapy (ISMETT), Division of Cardiac Surgery (Italy); Luca, Angelo, E-mail: aluca@ismett.ed [Mediterranean Institute of Transplantation and High Specialization Therapy (ISMETT), Diagnostic and Interventional Radiology (Italy); Gridelli, Bruno, E-mail: bgridelli@ismett.ed [Mediterranean Institute of Transplantation and High Specialization Therapy (ISMETT), Division of Surgery (Italy)

2010-02-15

173

Influences of Body Size and Cardiac Workload on the Left Ventricular Mass in Healthy Korean Adults with Normal Body Weight and Blood Pressure  

Microsoft Academic Search

Background and Objectives:The left ventricular mass is known to be influenced by both hemodynamic and non-hemodynamic factors. Body size and gender are the most representative non-hemodynamic factors. This study was performed to establish the influences of these variables on the variation of the left ventricular mass in healthy Korean adults. Subjects and Methods:368 subjects (male=184, female=184), with a normal body

Jinho Shin; Kyung Soo Kim; Jeong Hyun Kim; Heon Kil Lim

174

Implantation of a left ventricular assist device as a destination therapy in Duchenne muscular dystrophy patients with end stage cardiac failure: Management and lessons learned.  

PubMed

Duchenne muscular dystrophy (DMD) is an X-linked recessive disorder, characterized by progressive skeletal muscle weakness, loss of ambulation, and death secondary to cardiac or respiratory failure. End-stage dilated cardiomyopathy (DCM) is a frequent finding in DMD patients, they are rarely candidates for cardiac transplantation. Recently, the use of ventricular assist devices as a destination therapy (DT) as an alternative to cardiac transplantation in DMD patients has been described. Preoperative planning and patient selection play a significant role in the successful postoperative course of these patients. We describe the preoperative, intraoperative and postoperative management of Jarvik 2000 implantation in 4 DMD pediatric (age range 12-17 years) patients. We also describe the complications that may occur. The most frequent were bleeding and difficulty in weaning from mechanical ventilation. Our standard protocol includes: 1) preoperative multidisciplinary evaluation and selection, 2) preoperative and postoperative non-invasive ventilation and cough machine cycles, 3) intraoperative use of near infrared spectroscopy (NIRS) and transesophageal echocardiography, 4) attention on surgical blood loss, use of tranexamic acid and prothrombin complexes, 5) early extubation and 6) avoiding the use of nasogastric feeding tubes and nasal temperature probes. Our case reports describe the use of Jarvik 2000 as a destination therapy in young patients emphasizing the use of ventricular assist devices as a new therapeutic option in DMD. PMID:25444433

Iodice, Francesca; Testa, Giuseppina; Averardi, Marco; Brancaccio, Gianluca; Amodeo, Antonio; Cogo, Paola

2015-01-01

175

Heart Hydatid Cyst Close to the Left Descending Artery in a Thirteen-Year-Old Boy  

PubMed Central

Introduction: Hydatid cyst is a significant health problem in underdeveloped and developing countries, particularly among sheep breeders. Although cardiac involvement is seen only in 0.2% to 3% of the cases, early diagnosis and treatment are important. Case Presentation: A 13-year-old boy with dyspnea and atypical pericardial type chest pain for three months was referred to us. Chest X-ray revealed linear calcification in the left side of the heart. Computed tomography demonstrated a cyst with peripheral calcification and without internal septation in the lateral left ventricle (LV) myocardium. Serologic IgG test was positive for Echinococcosis. No other cyst was seen in the other organs such as the lungs and liver. By midline sternotomy on pump, an incision was made 2-cm lateral to the left ascending artery through the LV myocardium and without entering any cardiac chamber. After injecting hypertonic (5%) saline, the cyst was punctured and its fluid contents were aspirated, the cyst was enucleated, and the cavity marsupialization was done for protection of the myocardium. LV ejection fraction before operation was 40% but after operation and repairing LV myocardium, ejection fraction increased to 50% in. Histopathologic examination confirmed a hydatid cyst. Conclusions: In myocardial hydatid cysts, we recommend a direct approach without entering the cardiac chambers to avoid dissemination of the infection. We recommend excision of the germinative membrane without capitonnage to avoid impairment of myocardial contraction. PMID:25593721

Khosravi, Arezo; Taghipour, Hamidreza; Fanaei, Seyed Ahmad; Assar, Omid; Ghyasy, Mohammad Saaid; Mirlohi, Seyed Mohammad Javad

2014-01-01

176

Cross sectional study of contribution of clinical assessment and simple cardiac investigations to diagnosis of left ventricular systolic dysfunction in patients admitted with acute dyspnoea.  

PubMed Central

OBJECTIVE: To assess the comparative contribution of clinical assessment, electrocardiography, and chest radiography to the diagnosis of left ventricular systolic dysfunction in patients admitted to a general medical ward with acute dyspnoea. DESIGN: Prospective cross sectional study. SETTING: Acute medical admissions ward of a teaching hospital. SUBJECTS: 71 randomly selected patients admitted with acute dyspnoea. MAIN OUTCOME MEASURES: Sensitivity and specificity of each investigation and logistic regression analysis of each variable in identifying left ventricular systolic dysfunction. RESULTS: Clinical assessment in this cohort of patients with severe dyspnoea was generally sensitive (sensitivity 81%). Patients were divided into three groups on the basis of clinical assessment. In the first group (37 patients) the diagnosis of systolic dysfunction was clear, in the second (22) it was in doubt, and in the third (12) it was unlikely. The sensitivity of clinical assessment in identifying left ventricular systolic dysfunction was 81% and the specificity was 47%. The specificity of diagnosis was improved by electrocardiography (69%) and chest radiography (92%). Logistic regression analysis showed that isolated pulmonary crepitations were a comparatively poor predictor of left ventricular systolic dysfunction chi 2 = 10.215, P = 0.0014) but that a full clinical examination had reasonable predictive value (chi 2 = 24.82, P < 0.00001). The combination of clinical assessment and chest radiography improved the accuracy of diagnosis (chi 2 = 28.08, P < 0.00001), as did the combination of clinical assessment and electrocardiography (chi 2 = 32.41, P < 0.00001). CONCLUSION: Clinical assessment in patients admitted with acute dyspnoea is comparatively accurate. Patients with abnormal results on chest radiography, electrocardiography, and clinical examination have a high likelihood of having left ventricular systolic dysfunction. Echocardiography contributes little more to the diagnosis in these patients and may be more efficiently directed towards patients in whom the diagnosis is still in doubt after clinical assessment, chest radiography, and electrocardiography. PMID:9099117

Gillespie, N. D.; McNeill, G.; Pringle, T.; Ogston, S.; Struthers, A. D.; Pringle, S. D.

1997-01-01

177

Acute pressure overload of the right ventricle. Comparison of two models of right-left shunt. Pulmonary artery to left atrium and right atrium to left atrium: experimental study  

PubMed Central

Abtract Background In right ventricular failure (RVF), an interatrial shunt can relieve symptoms of severe pulmonary hypertension by reducing right ventricular preload and increasing systemic flow. Using a pig model to determine if a pulmonary artery - left atrium shunt (PA-LA) is better than a right atrial - left atrial shunt (RA-LA), we compared the hemodynamic effects and blood gases between the two shunts. Methods Thirty, male Large White pigs weighting in average 21.3 kg ± 0.7 (SEM) were divided into two groups (15 pigs per group): In group 1, banding of the pulmonary artery and a pulmonary artery to left atrium shunt with an 8 mm graft (PA-LA) was performed and in group 2 banding of the pulmonary artery and right atrial to left atrial shunt (RA-LA) with a similar graft was performed. Hemodynamic parameters and blood gases were measured from all cardiac chambers in 10 and 20 minutes, half and one hour interval from the baseline (30 min from the banding). Cardiac output and flow of at the left anterior descending artery was also monitored. Results In both groups, a stable RVF was generated. The PA-LA shunt compared to the RA-LA shunt has better hemodynamic performance concerning the decreased right ventricle afterload, the 4 fold higher mean pressure of the shunt, the better flow in left anterior descending artery and the decreased systemic vascular resistance. Favorable to the PA-LA shunt is also the tendency - although not statistically significant - in relation to central venous pressure, left atrial filling and cardiac output. Conclusion The PA-LA shunt can effectively reverse the catastrophic effects of acute RVF offering better hemodynamic characteristics than an interatrial shunt. PMID:22011551

2011-01-01

178

Echocardiographic examination of cardiac structure and function in elite cross trained male and female Alpine skiers  

PubMed Central

OBJECTIVE: To assess cardiac structure and function in elite cross- trained male and female athletes (Alpine skiers). METHODS: Sixteen athletes (10 male, six female) and 19 healthy sedentary control subjects (12 male, seven female) volunteered to take part in the study. Basic anthropometry determined height, body mass, body surface area, and fat free mass. Cardiac dimensions and function were determined by two dimensional, M mode, and Doppler echocardiography. Absolute data and data corrected for body size (allometrically determined) were compared by two way analysis of variance and post hoc Scheffe tests. RESULTS: Absolute left ventricular internal dimension in diastole (LVIDd), septal and posterior wall thickness and left ventricular mass were larger in athletes than controls (p < 0.05) and also increased in the men (p < 0.05) compared with women (except for septal thickness in controls). An increased LVIDd, septal thickness, posterior wall thickness, and left ventricular mass in athletes persisted after correction for body size except when LVIDd was scaled by fat free mass. Cardiac dimensions did not differ between the sexes after correction for body size. All functional indices were similar between groups. CONCLUSION: There is evidence of both left ventricular chamber dilatation and wall enlargement in cross trained athletes compared with controls. Differences in absolute cardiac dimensions between the sexes were primarily due to greater body dimensions in the men. ??? PMID:10205689

George, K. P.; Gates, P. E.; Whyte, G.; Fenoglio, R. A.; Lea, R.

1999-01-01

179

Age and gender-specific differences in left and right ventricular cardiac function and mass determined by cine magnetic resonance imaging  

Microsoft Academic Search

.   We examined possible age- and gender-specific differences in the function and mass of left (LV) and right (RV) ventricles\\u000a in 36 healthy volunteers using cine gradient-recalled echo magnetic resonance imaging. Subjects were divided into four groups\\u000a (nine men and nine women in each): men aged under 45 years (32 ± 7), women aged under 45 (27 ± 6), men

J. Sandstede; C. Lipke; M. Beer; S. Hofmann; T. Pabst; W. Kenn; S. Neubauer; D. Hahn

2000-01-01

180

Fetal cardiac anomalies  

Microsoft Academic Search

Fetal cardiac anomalies are increasingly identified during regular obstetric scanning. About 21000 pregnancies will have an abnormality of the four chamber view and a further 11000 will have an abnormality of the great arteries. These cases can then be referred to the specialist in fetal cardiology for further evaluation and counselling. There is a higher rate of chromosomal and other

Lindsey D. Allan

1996-01-01

181

Exposure chamber  

DOEpatents

A chamber for exposing animals, plants, or materials to air containing gases or aerosols is so constructed that catch pans for animal excrement, for example, serve to aid the uniform distribution of air throughout the chamber instead of constituting obstacles as has been the case in prior animal exposure chambers. The chamber comprises the usual imperforate top, bottom and side walls. Within the chamber, cages and their associated pans are arranged in two columns. The pans are spaced horizontally from the walls of the chamber in all directions. Corresponding pans of the two columns are also spaced horizontally from each other. Preferably the pans of one column are also spaced vertically from corresponding pans of the other column. Air is introduced into the top of the chamber and withdrawn from the bottom. The general flow of air is therefore vertical. The effect of the horizontal pans is based on the fact that a gas flowing past the edge of a flat plate that is perpendicular to the flow forms a wave on the upstream side of the plate. Air flows downwardly between the chamber walls and the outer edges of the pan. It also flows downwardly between the inner edges of the pans of the two columns. It has been found that when the air carries aerosol particles, these particles are substantially uniformly distributed throughout the chamber.

Moss, Owen R. (Kennewick, WA)

1980-01-01

182

A biplane roentgen videometry system for dynamic /60 per second/ studies of the shape and size of circulatory structures, particularly the left ventricle.  

NASA Technical Reports Server (NTRS)

A roentgen-television digital-computer technique and a display system developed for dynamic circulatory structure studies are described. Details are given for a videoroentgenographic setup which is used for obtaining biplane roentgen silhouettes of a left ventricle. A 60 per sec measurement of the shape and volume of angiographically outlined cardiac chambers can be made by this technique along with simultaneous ECG, pressure, and flow measurements accessible for real-time digital computer processing and analysis.

Ritman, E. L.; Sturm, E.; Wood, E. H.; Heintzen, P. H.

1971-01-01

183

A patient with ischemic symptoms presents with left coronary artery-to-right ventricle fistula and agenesis of the right coronary artery.  

PubMed

Coronary artery fistulas are rare vascular anomalies characterized by abnormal communication, devoid of a capillary system between the coronary artery and the major vessels or cardiac chambers. In this report, we present a 14-year-old male patient with ischemic symptoms, a left coronary artery to right ventricle fistula and agenesis of the right coronary artery. The anatomy of the coronary arteriovenous fistula was determined in detail through a dual source CT coronary angiography. The patient underwent open cardiac surgery because of ischemic symptoms and a residual fistula was detected after the surgery. PMID:23760124

Genç, Berhan; Solak, Aynur; Doksöz, Onder; Tavl?, Vedide

2013-06-01

184

Wire chamber  

DOEpatents

A wire chamber or proportional counter device, such as Geiger-Mueller tube or drift chamber, improved with a gas mixture providing a stable drift velocity while eliminating wire aging caused by prior art gas mixtures. The new gas mixture is comprised of equal parts argon and ethane gas and having approximately 0.25% isopropyl alcohol vapor.

Atac, Muzaffer (Wheaton, IL)

1989-01-01

185

Left ventricular functional assessment in murine models of ischemic and dilated cardiomyopathy using [18?F]FDG-PET: comparison with cardiac MRI and monitoring erythropoietin therapy  

PubMed Central

Background We performed an initial evaluation of non-invasive ECG-gated [18?F]FDG-positron emission tomography (FDG-PET) for serial measurements of left ventricular volumes and function in murine models of dilated (DCM) and ischemic cardiomyopathy (ICM), and then tested the effect of erythropoietin (EPO) treatment on DCM mice in a preliminary FDG-PET therapy monitoring study. Methods Mice developed DCM 8?weeks after injection with Coxsackievirus B3 (CVB3), whereas ICM was induced by ligation of the left anterior descending artery. LV volumes (EDV and ESV) and the ejection fraction (LVEF) of DCM, ICM and healthy control mice were measured by FDG-PET and compared with reference standard results obtained with 1.5?T magnetic resonance imaging (MRI). In the subsequent monitoring study, LVEF of DCM mice was evaluated by FDG-PET at baseline, and after 4?weeks of treatment, with EPO or saline. Results LV volumes and the LVEF as measured by FDG-PET correlated significantly with the MRI results. These correlations were higher in healthy and DCM mice than in ICM mice, in which LVEF measurements were somewhat compromised by absence of FDG uptake in the area of infarction. LV volumes (EDV and ESV) were systematically underestimated by FDG-PET, with net bias such that LVEF measurements in both models of heart disease exceeded by 15% to 20% results obtained by MRI. In our subsequent monitoring study of DCM mice, we found a significant decrease of LVEF in the EPO group, but not in the saline-treated mice. Moreover, LVEF in the EPO and saline mice significantly correlated with histological scores of fibrosis. Conclusions LVEF estimated by ECG-gated FDG-PET significantly correlated with the reference standard MRI, most notably in healthy mice and mice with DCM. FDG-PET served for longitudinal monitoring of effects of EPO treatment in DCM mice. PMID:22863174

2012-01-01

186

Heart rate reduction for 36 months with ivabradine reduces left ventricular mass in cardiac allograft recipients: a long-term follow-up study  

PubMed Central

Background Due to graft denervation, sinus tachycardia is a common problem after heart transplantation, underlining the importance of heart rate control without peripheral effects. However, long-term data regarding the effects of ivabradine, a novel If channel antagonist, are limited in patients after heart transplantation. Methods In this follow-up analysis, the resting heart rate, left ventricular mass indexed to body surface area (LVMI), tolerability, and safety of ivabradine therapy were evaluated at baseline and after 36 months in 30 heart transplant recipients with symptomatic sinus tachycardia versus a matched control group. Results During the study period, ivabradine medication was stopped in three patients (10% of total). Further analysis was based on 27 patients with 36 months of drug intake. The mean patient age was 53.3±11.3 years and mean time after heart transplantation was 5.0±4.8 years. After 36 months, the mean ivabradine dose was 12.0±3.4 mg/day. Resting heart rate was reduced from 91.0±10.7 beats per minute before initiation of ivabradine therapy (ie, baseline) to 81.2±9.8 beats per minute at follow-up (P=0.0006). After 36 months of ivabradine therapy, a statistically significant reduction of LVMI was observed (104.3±22.7 g at baseline versus 93.4±18.4 g at follow-up, P=0.002). Hematologic, renal, and liver function parameters remained stable during ivabradine therapy. Except for a lower mycophenolate mofetil dose at follow-up (P=0.02), no statistically significant changes in immunosuppressive drug dosage or blood levels were detected. No phosphenes were observed during 36 months of ivabradine intake despite active inquiry. Conclusion In line with previously published 12-month data, heart rate reduction with ivabradine remained effective and safe in chronic stable patients after heart transplantation, and also during 36-month long-term follow-up. Further, a significant reduction of LVMI was observed only during ivabradine therapy. Therefore, ivabradine may have a sustained long-term beneficial effect with regard to left ventricular remodeling in heart transplant patients. PMID:24235815

Doesch, Andreas O; Mueller, Susanne; Erbel, Christian; Gleissner, Christian A; Frankenstein, Lutz; Hardt, Stefan; Ruhparwar, Arjang; Ehlermann, Philipp; Dengler, Thomas; Katus, Hugo A

2013-01-01

187

New design for an endo-esophageal probe intended for the ablation of cardiac muscle in the left-atrium: A parametric simulation study  

NASA Astrophysics Data System (ADS)

A parametric simulation study was carried out to establish optimal dimensions of endo-esophageal devices intended to treat the atrial fibrillation (AF). The devices are spherical-surface sections truncated at 15 mm (depth of 4 mm) and cut in concentric-rings each composed of independently driven sectors. The number of independent elements (N) was minimized for different values of ratio of amplitude of secondary lobe over main lobe (E) of 0.35, 0.4, 0.45 and 0.5 and for a volume of interest (VOI) of 24×27×28 mm3 (located at 23.5 mm from the center of the device), which is large enough to contain all the targets identified in the Visible Human Project Male specimen. Operating at 1 MHz, E and N were calculated in function of the element size and focal length (F). After keeping values of F and normalized dimensions of the independent elements in terms of wavelength, higher frequencies were considered: 1.25 and 1.5 MHz. Lesion formation in the heart chamber showed that the twelve configurations were able to produce the typical lesion used to treat the AF while preserving surrounding structures. For an exposure of 5 s and maximal temperature of 70 ?C, the average (s.d.) acoustical intensity at transducer surface varied from 22.3(5.8)W/cm2 for a device with F = 98 mm at 1 MHz to 9.2(2.1)W/cm2 for a device with F = 186 mm at 1.5 MHz, while requiring 319 and 1158 elements, respectively, and achieving values of E of 0.5 and 0.41, respectively.

Pichardo, Samuel; Hynynen, Kullervo

2009-04-01

188

A Prospective Pilot Study to Evaluate the Relationship Between Acute Change in Left Ventricular Synchrony After Cardiac Resynchronization Therapy and Patient Outcome Using a Single-Injection Gated SPECT Protocol  

PubMed Central

Background There are ongoing efforts to optimize patient selection criteria for cardiac resynchronization therapy (CRT). In this regard, the relationship between acute change in left ventricular synchrony (LV) after CRT and patient outcome remains undefined. Methods and Results A novel protocol was designed to evaluate acute change in left LV synchrony after CRT using phase analysis of standard gated single-photon emission computed tomography (SPECT) myocardial perfusion imaging with a single injection of radiotracer and prospectively applied to 44 patients undergoing CRT. Immediately after CRT, 18 (41%), 11 (25%), and 15 (34%) patients had an improvement, no change, or a worsening in LV synchrony. An algorithm incorporating the presence of baseline dyssynchrony, myocardial scar burden, and lead concordance predicted acute improvement or no change in LV synchrony with 72% sensitivity, 93% specificity, 96% positive predictive value, and 64% negative predictive value and had 96% negative predictive value for acute deterioration in synchrony. Over a follow-up period of 9.6±6.8 months, patients who had an acute deterioration in synchrony after CRT had a higher composite event rate of death, heart failure hospitalizations, appropriate defibrillator discharges, and CRT device deactivation for worsening heart failure symptoms, compared with patients who had an improvement or no change [hazard ratio, 4.6 (1.3 to 16.0); log rank test; P=0.003]. Conclusions In this single-center pilot study, phase analysis of gated SPECT was successfully used to predict acute change in LV synchrony and patient outcome after CRT. PMID:21772007

Friehling, Mati; Chen, Ji; Saba, Samir; Bazaz, Raveen; Schwartzman, David; Adelstein, Evan C.; Garcia, Ernest; Follansbee, William; Soman, Prem

2013-01-01

189

Exercises in anatomy: cardiac isomerism.  

PubMed

It is well recognized that the patients with the most complex cardiac malformations are those with so-called visceral heterotaxy. At present, it remains a fact that most investigators segregate these patients on the basis of their splenic anatomy, describing syndromes of so-called asplenia and polysplenia. It has also been known for quite some time, nonetheless, that the morphology of the tracheobronchial tree is usually isomeric in the setting of heterotaxy. And it has been shown that the isomerism found in terms of bronchial arrangement correlates in a better fashion with the cardiac anatomy than does the presence of multiple spleens, or the absence of any splenic tissue. In this exercise in anatomy, we use hearts from the Idriss archive of Lurie Children's Hospital in Chicago to demonstrate the isomeric features found in the hearts obtained from patients known to have had heterotaxy. We first demonstrate the normal arrangements, showing how it is the extent of the pectinate muscles in the atrial appendages relative to the atrioventricular junctions that distinguishes between morphologically right and left atrial chambers. We also show the asymmetry of the normal bronchial tree, and the relationships of the first bronchial branches to the pulmonary arteries supplying the lower lobes of the lungs. We then demonstrate that diagnosis of multiple spleens requires the finding of splenic tissue on either side of the dorsal mesogastrium. Turning to hearts obtained from patients with heterotaxy, we illustrate isomeric right and left atrial appendages. We emphasize that it is only the appendages that are universally isomeric, but point out that other features support the notion of cardiac isomerism. We then show that description also requires a full account of veno-atrial connections, since these can seemingly be mirror-imaged when the arrangement within the heart is one of isomerism of the atrial appendages. We show how failure to recognize the presence of such isomeric appendages can lead to spurious diagnoses of discordant atrioventricular connections. Overall, we show that the finding of isomeric atrial appendages, guided by the finding of bronchial isomerism, is but the prelude to full segmental sequential analysis. PMID:25547620

Anderson, Robert H; Sarwark, Anne E; Spicer, Diane E; Backer, Carl L

2014-01-01

190

Left ventricular myxoma: a case report  

PubMed Central

Cardiac myxoma, the most common primary heart tumor, is located mainly in the left atrium. We reported a rare case of left ventricular myxoma incidentally found on echocardiography in an asymptomatic 60-year-old male. The tumor was carefully resected without fragmentation. The patient had an uneventful recovery and was discharged home on the 4th postoperative day. Surgical resection of this type of cardiac myxoma is recommended due to the rarity of tumor location. PMID:25469121

Qin, Wei; Wang, Liming; Chen, Xin; Liu, Peisheng; Wang, Rui

2014-01-01

191

Ionization chamber  

DOEpatents

An ionization chamber has separate drift and detection regions electrically isolated from each other by a fine wire grid. A relatively weak electric field can be maintained in the drift region when the grid and another electrode in the chamber are connected to a high voltage source. A much stronger electric field can be provided in the detection region by connecting wire electrodes therein to another high voltage source. The detection region can thus be operated in a proportional mode when a suitable gas is contained in the chamber. High resolution output pulse waveforms are provided across a resistor connected to the detection region anode, after ionizing radiation enters the drift region and ionize the gas.

Walenta, Albert H. (Port Jefferson Station, NY)

1981-01-01

192

Cardiac mechanics: Physiological, clinical, and mathematical considerations  

NASA Technical Reports Server (NTRS)

Recent studies concerning the basic physiological and biochemical principles underlying cardiac muscle contraction, methods for the assessment of cardiac function in the clinical situation, and mathematical approaches to cardiac mechanics are presented. Some of the topics covered include: cardiac ultrastructure and function in the normal and failing heart, myocardial energetics, clinical applications of angiocardiography, use of echocardiography for evaluating cardiac performance, systolic time intervals in the noninvasive assessment of left ventricular performance in man, evaluation of passive elastic stiffness for the left ventricle and isolated heart muscle, a conceptual model of myocardial infarction and cardiogenic shock, application of Huxley's sliding-filament theory to the mechanics of normal and hypertrophied cardiac muscle, and a rheological modeling of the intact left ventricle. Individual items are announced in this issue.

Mirsky, I. (editor); Ghista, D. N.; Sandler, H.

1974-01-01

193

Upper arm circumference is an independent predictor of left ventricular concentric hypertrophy in hypertensive women.  

PubMed

Upper arm circumference (UAC) measurement is necessary for the proper sizing of cuffs and is recommended for accurate blood pressure (BP) assessment. The aim of this report is to identify and quantify the relationships between UAC and the usual anthropometric measurements of body fat distribution and cardiac structure in hypertensive subjects. We evaluated 339 patients (202 women and 137 men) by medical history, physical examination, anthropometry, metabolic and inflammatory parameters, and echocardiography. Partial correlation analyses adjusted for age and body mass index revealed that anthropometric variables were significantly associated with echocardiographic parameters exclusively in women. In this regard, UAC correlated with interventricular septum thickness, posterior wall thickness, and relative wall thickness >or=0.45, while waist circumference was related to left cardiac chamber diameter. Multivariate analyses including age, body mass index, systolic BP, homeostasis model assessment index, and use of antihypertensive medications demonstrated that UAC was an independent predictor of left ventricular wall thickness and concentric hypertrophy in women. Further linear regression analyses revealed that waist circumference was an independent predictor of left ventricular end-diastolic and left atrial diameters in this gender. Overall, these findings suggest that UAC determination might serve not only as a routine approach preceding BP evaluation but also as a simple and feasible predictor of adverse LV remodeling in hypertensive women. PMID:18716366

Pio-Magalhães, José A; Cornélio, Marília; Leme, Cid A; Matos-Souza, José R; Garlipp, Célia R; Gallani, Maria C J; Rodrigues, Roberta C; Franchini, Kleber G; Nadruz, Wilson

2008-06-01

194

Multiple Papillary Fibroelastomas and Thrombus in the Left Heart  

PubMed Central

Cardiac papillary fibroelastomas (CPF) are benign cardiac tumors and usually discovered incidentally during echocardiography. This report describes the case of a 68-year-old man, referred to cardiology for multiple masses of the left ventricle and left atrium. The transthoracic echocardiography revealed multiple oscillating masses in the left ventricle and aortic valve, non-mobile mass in the left atrium with severe mitral stenosis and moderate aortic regurgitation. The patient underwent surgical resection of the masses with valve replacements. Histopathologic examination confirmed the diagnosis of CPF in the left ventricle and aortic valve, thrombus in the left atrium. PMID:24753809

Seo, Guang-Won; Park, Bo-Min; Kim, Tae-Jin; Kim, Jae-Kyun; Song, Pil-Sang; Kim, Dong-Kie; Kim, Ki-Hun; Kim, Yeon Mee; Kim, Doo-Il

2014-01-01

195

Multiple papillary fibroelastomas and thrombus in the left heart.  

PubMed

Cardiac papillary fibroelastomas (CPF) are benign cardiac tumors and usually discovered incidentally during echocardiography. This report describes the case of a 68-year-old man, referred to cardiology for multiple masses of the left ventricle and left atrium. The transthoracic echocardiography revealed multiple oscillating masses in the left ventricle and aortic valve, non-mobile mass in the left atrium with severe mitral stenosis and moderate aortic regurgitation. The patient underwent surgical resection of the masses with valve replacements. Histopathologic examination confirmed the diagnosis of CPF in the left ventricle and aortic valve, thrombus in the left atrium. PMID:24753809

Seo, Guang-Won; Seol, Sang-Hoon; Park, Bo-Min; Kim, Tae-Jin; Kim, Jae-Kyun; Song, Pil-Sang; Kim, Dong-Kie; Kim, Ki-Hun; Kim, Yeon Mee; Kim, Doo-Il

2014-03-01

196

Magma chambers  

NASA Technical Reports Server (NTRS)

Recent observational and theoretical investigations of terrestrial magma chambers (MCs) are reviewed. Consideration is given to the evidence for MCs with active convection and crystal sorting, problems of direct MC detection, theoretical models of MC cooling, the rheology and dynamics of solidification fronts, crystal capture and differentiation, convection with solidification, MC wall flows, and MC roof melting. Diagrams, graphs, and a list of problems requiring further research are provided.

Marsh, Bruce D.

1989-01-01

197

Isolated noncompaction left ventricular myocardium and polymorphic ventricular tachycardia.  

PubMed

A 57-year-old woman with syncope was admitted. She had a family history of sudden death: two brothers had died suddenly at the age of 47. Transesophageal echocardiography showed numerous prominent trabeculations and deep intertrabecular recesses in the anterior and lateroapical zones. Isotopic left ventricular ejection fraction was 46%. Cardiac catheterization showed coronary arteries with no angiographic lesions. A prominent trabecular zone and deep intertrabecular recesses were seen in the anterior wall on left ventriculography. Right ventriculography was normal. The diagnosis of isolated noncompaction left ventricular myocardium was established. Continuous 24-h electrocardiographic registry showed episodes of polymorphic ventricular tachycardia. Programmed ventricular stimulation performed at the right ventricular apex with up to three extrastimuli failed to induce ventricular arrhythmias. Treatment with beta blockers was initiated, but short runs of polymorphic ventricular tachycardia persisted. A dual-chamber automatic implantable defibrillator was implanted. We discuss the physiopathology of the arrhythmia. It appears that several factors could be responsible for the malignant arrhythmias in this entity. PMID:12539813

Serés, Luis; Lopez, Jorge; Larrousse, Eduardo; Moya, Angel; Pereferrer, Damian; Valle, Vicente

2003-01-01

198

Malignant phyllodes tumor of the left atrium  

PubMed Central

Metastatic tumors to the heart usually involve right sided chambers. We report a rare case of malignant phyllodes tumor of breast with metastatic involvement of left atrium occurring through direct invasion from mediastinal micro-metastasis and presenting as a left atrial mass causing arrhythmia. PMID:24814127

Bhambhani, Anupam; Ayyagari, Sudha; Mohapatra, Tushar; Rehman, Syed Abdul; Shah, Milap; Rao, Sudhakar; Rangashamanna, Vital; Rajasekhar, V.; Chittimilla, Santosh

2014-01-01

199

Cardiac myxosarcoma with thoracic spinal metastasis.  

PubMed

Echocardiography revealed a left atrial tumor in a 59-year-old man with back pain that concurrently worsened with left foot drop and loss of the left ankle reflex soon after admission to our hospital. Magnetic resonance imaging of the spine revealed an epidural tumor extending from Th5 with spinal cord compression. The patient was immediately treated by emergency Th4-5 laminectomy and epidural decompression. One month later, a cardiac tumor excised via the left atrial approach was histopathologically diagnosed as myxosarcoma, and the Th5 tumor was consistent with this finding. This is the first report to describe spinal metastasis of cardiac myxosarcoma. PMID:23677508

Kimura, Mitsuhiro; Kikuchi, Chizuo; Takahashi, Yoshiki; Kanazawa, Hiroshi; Nakazawa, Satoshi

2014-07-01

200

Heart chambers and whole heart segmentation techniques: review  

E-print Network

Heart chambers and whole heart segmentation techniques: review Dongwoo Kang Jonghye Woo Piotr J://electronicimaging.spiedigitallibrary.org/ on 01/15/2014 Terms of Use: http://spiedl.org/terms #12;Heart chambers and whole heart segmentation this problem. Recent studies employ sophisticated techniques using available cues from cardiac anatomy

Kuo, C.-C. "Jay"

201

Left atrial dissection: an almost unknown entity.  

PubMed

Left atrial dissection is an exceedingly rare but potentially fatal complication of cardiac surgery. It is most commonly associated with mitral valve surgery, including both replacement and repair, with a reported incidence rate of 0.16%. However, other cardiac surgical or catheter-based interventional procedures are also known as potential predisposing factors. The time of presentation from the cause of dissection varies extremely, ranging from immediate occurrence up to 20 years later. The dissection forms a large cavity between the endocardium and epicardium of the left atrium, causing obliteration of the left atrial cavity and resultant haemodynamic compromise, which almost always requires immediate surgical intervention. In contrast, left atrial dissection without haemodynamic instability can often be managed non-operatively with satisfactory outcomes. This article reviews this rare but relevant clinical entity to further elucidate the incidence, pathogenesis, clinical course, management and outcome of left atrial dissection. PMID:25260895

Fukuhara, Shinichi; Dimitrova, Kamellia R; Geller, Charles M; Hoffman, Darryl M; Tranbaugh, Robert F

2015-01-01

202

Cardiac remodeling caused by transgenic overexpression of a corn Rac gene.  

PubMed

Rac1-GTPase activation plays a key role in the development and progression of cardiac remodeling. Therefore, we engineered a transgenic mouse model by overexpressing cDNA of a constitutively active form of Zea maize Rac gene (ZmRacD) specifically in the hearts of FVB/N mice. Echocardiography and MRI analyses showed cardiac hypertrophy in old transgenic mice, as evidenced by increased left ventricular (LV) mass and LV mass-to-body weight ratio, which are associated with relative ventricular chamber dilation and systolic dysfunction. LV hypertrophy in the hearts of old transgenic mice was further confirmed by an increased heart weight-to-body weight ratio and histopathology analysis. The cardiac remodeling in old transgenic mice was coupled with increased myocardial Rac-GTPase activity (372%) and ROS production (462%). There were also increases in ?(1)-integrin (224%) and ?(1)-integrin (240%) expression. This led to the activation of hypertrophic signaling pathways, e.g., ERK1/2 (295%) and JNK (223%). Pravastatin treatment led to inhibition of Rac-GTPase activity and integrin signaling. Interestingly, activation of ZmRacD expression with thyroxin led to cardiac dilation and systolic dysfunction in adult transgenic mice within 2 wk. In conclusion, this is the first study to show the conservation of Rho/Rac proteins between plant and animal kingdoms in vivo. Additionally, ZmRacD is a novel transgenic model that gradually develops a cardiac phenotype with aging. Furthermore, the shift from cardiac hypertrophy to dilated hearts via thyroxin treatment will provide us with an excellent system to study the temporal changes in cardiac signaling from adaptive to maladaptive hypertrophy and heart failure. PMID:21622832

Elnakish, Mohammad T; Awad, Mohamed M; Hassona, Mohamed D H; Alhaj, Mazin A; Kulkarni, Aditi; Citro, Lucas A; Sayyid, Muzzammil; Abouelnaga, Zeinb A; El-Sayed, Osama; Kuppusamy, Periannan; Moldovan, Leni; Khan, Mahmood; Hassanain, Hamdy H

2011-09-01

203

Treatment of massive cardiac thrombi in a patient with protein C and protein S deficiency.  

PubMed

Myocarditis and dilated cardiomyopathy is characterized by dilatation of all four cardiac chambers and decreased systolic function of the heart, especially in the left ventricle. In this report we presented a patient with myocarditis or dilated cardiomyopathy and deficiency of protein C and protein S with biventricular multiple intracardiac thrombi. Standard heparin infusion and acetyl salicylic acid was begun. On the 10th day of hospitalization the right ventricular thrombus disappeared, and on the 24th day all thrombi in the left ventricle disappeared. During the treatment we did not observe any complication such as hemorrhagia or embolism. We think that patients with dilated cardiomyopathy or myocarditis should be evaluated for hemostatic disorders, and should be anticoagulated if any of these disorders are presented. PMID:17890961

Paç, F Ay?enur; Ca?da?, Deniz N

2007-10-01

204

Growth and remodeling of the left ventricle: A case study of myocardial infarction and surgical ventricular restoration  

PubMed Central

Cardiac growth and remodeling in the form of chamber dilation and wall thinning are typical hallmarks of infarct-induced heart failure. Over time, the infarct region stiffens, the remaining muscle takes over function, and the chamber weakens and dilates. Current therapies seek to attenuate these effects by removing the infarct region or by providing structural support to the ventricular wall. However, the underlying mechanisms of these therapies are unclear, and the results remain suboptimal. Here we show that myocardial infarction induces pronounced regional and transmural variations in cardiac form. We introduce a mechanistic growth model capable of predicting structural alterations in response to mechanical overload. Under a uniform loading, this model predicts non-uniform growth. Using this model, we simulate growth in a patient-specific left ventricle. We compare two cases, growth in an infarcted heart, pre-operative, and growth in the same heart, after the infarct was surgically excluded, post-operative. Our results suggest that removing the infarct and creating a left ventricle with homogeneous mechanical properties does not necessarily reduce the driving forces for growth and remodeling. These preliminary findings agree conceptually with clinical observations. PMID:22778489

Klepach, Doron; Lee, Lik Chuan; Wenk, Jonathan F.; Ratcliffe, Mark B.; Zohdi, Tarek I.; Navia, Jose A.; Kassab, Ghassan S.; Kuhl, Ellen; Guccione, Julius M.

2012-01-01

205

Dose to the cardiac vascular and conduction systems in primary breast irradiation  

SciTech Connect

Using computerized tomography (CT) in which cardiac anatomy was defined, doses delivered to the cardiac compartments, vascular and conduction systems were assessed for various standard techniques of primary breast irradiation. Included in the analysis were 6 MV photon tangents (T) alone, or in conjunction with a separate internal mammary field (IMF). Beams evaluated in the IMF were 6 MV photons, 12 MeV electron beam, and mixed photon/electron beam; Cobalt 60 was also analyzed as an alternate photon beam. Treatment of the IMF with photons, either alone or in combination with electron beam, delivered doses ranging between 30 Gy to 50 Gy to all chambers of the heart, coronary arteries and branches of the conduction system. Complete sparing of the posterior cardiac structures and volume is accomplished with treatment plans using tangents alone or in combination with 12 MeV electron beam irradiation to the IMF. Sparing of the anterior wall of the left ventricle, Bundle of His and left anterior descending coronary artery is also achieved in treatment with tangents and 12 MeV electron beam IMF. Doses to this region with tangents alone ranged from 20 Gy to 45 Gy compared to 0 to 30 Gy with tangents and 12 MeV electron beam IMF. Clinical significance of these findings will be discussed.

Janjan, N.A.; Gillin, M.T.; Prows, J.; Arnold, S.; Haasler, G.; Thorsen, M.K.; Wilson, J.F. (Medical College of Wisconsin, Milwaukee (USA))

1989-01-01

206

An integrated platform for image-guided cardiac resynchronization therapy  

NASA Astrophysics Data System (ADS)

Cardiac resynchronization therapy (CRT) is an effective procedure for patients with heart failure but 30% of patients do not respond. This may be due to sub-optimal placement of the left ventricular (LV) lead. It is hypothesized that the use of cardiac anatomy, myocardial scar distribution and dyssynchrony information, derived from cardiac magnetic resonance imaging (MRI), may improve outcome by guiding the physician for optimal LV lead positioning. Whole heart MR data can be processed to yield detailed anatomical models including the coronary veins. Cine MR data can be used to measure the motion of the LV to determine which regions are late-activating. Finally, delayed Gadolinium enhancement imaging can be used to detect regions of scarring. This paper presents a complete platform for the guidance of CRT using pre-procedural MR data combined with live x-ray fluoroscopy. The platform was used for 21 patients undergoing CRT in a standard catheterization laboratory. The patients underwent cardiac MRI prior to their procedure. For each patient, a MRI-derived cardiac model, showing the LV lead targets, was registered to x-ray fluoroscopy using multiple views of a catheter looped in the right atrium. Registration was maintained throughout the procedure by a combination of C-arm/x-ray table tracking and respiratory motion compensation. Validation of the registration between the three-dimensional (3D) roadmap and the 2D x-ray images was performed using balloon occlusion coronary venograms. A 2D registration error of 1.2 ± 0.7 mm was achieved. In addition, a novel navigation technique was developed, called Cardiac Unfold, where an entire cardiac chamber is unfolded from 3D to 2D along with all relevant anatomical and functional information and coupled to real-time device detection. This allowed more intuitive navigation as the entire 3D scene was displayed simultaneously on a 2D plot. The accuracy of the unfold navigation was assessed off-line using 13 patient data sets by computing the registration error of the LV pacing lead electrodes which was found to be 2.2 ± 0.9 mm. Furthermore, the use of Unfold Navigation was demonstrated in real-time for four clinical cases.

Ma, Ying Liang; Shetty, Anoop K.; Duckett, Simon; Etyngier, Patrick; Gijsbers, Geert; Bullens, Roland; Schaeffter, Tobias; Razavi, Reza; Rinaldi, Christopher A.; Rhode, Kawal S.

2012-05-01

207

Mastering temporary invasive cardiac pacing.  

PubMed

Competent management of patients with an invasive temporary pacemaker is an important skill for nurses who provide care for critically ill patients with cardiac disease. Such management requires familiarity with normal cardiovascular anatomy and physiology, conduction system defects, and rhythm interpretation. With an understanding of the basic concepts of rate, output, chambers, sensitivity, and capture, pacing can be done with ease. Care of patients with a temporary invasive pacemaker requires monitoring cardiac tissue and hemodynamic status, observing for changes that would indicate the need for modifications in the pacemaker settings. Nursing interventions include physical assessment, care of the insertion site, routine threshold testing, and management of the pulse generator. PMID:15206293

Overbay, Devorah; Criddle, Laura

2004-06-01

208

Differential Gene Expression of Cardiac Ion Channels in Human Dilated Cardiomyopathy  

PubMed Central

Background Dilated cardiomyopathy (DCM) is characterized by idiopathic dilation and systolic contractile dysfunction of the cardiac chambers. The present work aimed to study the alterations in gene expression of ion channels involved in cardiomyocyte function. Methods and Results Microarray profiling using the Affymetrix Human Gene® 1.0 ST array was performed using 17 RNA samples, 12 from DCM patients undergoing cardiac transplantation and 5 control donors (CNT). The analysis focused on 7 cardiac ion channel genes, since this category has not been previously studied in human DCM. SCN2B was upregulated, while KCNJ5, KCNJ8, CLIC2, CLCN3, CACNB2, and CACNA1C were downregulated. The RT-qPCR (21 DCM and 8 CNT samples) validated the gene expression of SCN2B (p < 0.0001), KCNJ5 (p < 0.05), KCNJ8 (p < 0.05), CLIC2 (p < 0.05), and CACNB2 (p < 0.05). Furthermore, we performed an IPA analysis and we found a functional relationship between the different ion channels studied in this work. Conclusion This study shows a differential expression of ion channel genes involved in cardiac contraction in DCM that might partly underlie the changes in left ventricular function observed in these patients. These results could be the basis for new genetic therapeutic approaches. PMID:24339868

Molina-Navarro, Maria Micaela; Roselló-Lletí, Esther; Ortega, Ana; Tarazón, Estefanía; Otero, Manuel; Martínez-Dolz, Luis; Lago, Francisca; González-Juanatey, José Ramón; España, Francisco; García-Pavía, Pablo; Montero, José Anastasio; Portolés, Manuel; Rivera, Miguel

2013-01-01

209

Granulocyte-CSF induced inflammation-associated cardiac thrombosis in iron loading mouse heart and can be attenuated by statin therapy  

PubMed Central

Background Granulocyte colony-stimulating factor (G-CSF), a hematopoietic cytokine, was recently used to treat patients of acute myocardial infarction with beneficial effect. However, controversy exists as some patients developed re-stenosis and worsened condition post G-CSF delivery. This study presents a new disease model to study G-CSF induced cardiac thrombosis and delineate its possible mechanism. We used iron loading to mimic condition of chronic cardiac dysfunction and apply G-CSF to mice to test our hypothesis. Methods and Results Eleven out of fifteen iron and G-CSF treated mice (I+G) showed thrombi formation in the left ventricular chamber with impaired cardiac function. Histological analysis revealed endothelial fibrosis, increased macrophage infiltration and tissue factor expression in the I+G mice hearts. Simvastatin treatment to I+G mice attenuated their cardiac apoptosis, iron deposition, and abrogated thrombus formation by attenuating systemic inflammation and leukocytosis, which was likely due to the activation of pAKT activation. However, thrombosis in I+G mice could not be suppressed by platelet receptor inhibitor, tirofiban. Conclusions Our disease model demonstrated that G-CSF induces cardiac thrombosis through an inflammation-thrombosis interaction and this can be attenuated via statin therapy. Present study provides a mechanism and potential therapy for G-CSF induced cardiac thrombosis. PMID:21496220

2011-01-01

210

Concrete induced cardiac contusion.  

PubMed

A previously fit 22 year old man was struck in the chest by a concrete block dropped through the windscreen of his car while he was driving on the motorway. He suffered extensive chest wall trauma and lung contusion, which subsequently precipitated acute respiratory distress. On admission ECG showed right bundle branch block and left axis deviation. Three days later QRS duration was normal but there was anterior ST segment elevation and subsequent T wave change. There was a large rise in creatine kinase, and echocardiography revealed septal and apical hyokinesis as well as a mobile mass attached to the left side of the interventricular septum, which had the echogenic texture of myocardium. The patient had fixed perfusion defects in the areas of hypokinesis on thallium scanning but the coronary arteries were unobstructed at angiography. He was treated with warfarin in the short term and an angiotensin converting enzyme inhibitor in the longer term and has made an asymptomatic recovery. Outpatient echocardiography two months after the injury demonstrated some recovery in overall left ventricular systolic function and no evidence of the intracardiac mass. This case illustrates some of the typical features of non-fatal cardiac contusion associated with non-penetrating cardiac trauma, and was complicated by partial thickness avulsion of a strip of the myocardium in the interventricular septum. PMID:9391297

Curzen, N; Brett, S; Fox, K

1997-09-01

211

Thromboexclusion of an atypical left ventricular pseudoaneurysm.  

PubMed

Left ventricular pseudoaneurysm is rare in children. The gold standard for treatment has been surgical repair. Here, we describe a boy in whom an atypical left ventricular pseudoaneurysm was treated through staged transcatheter procedures. In addition, we highlight the importance of the preprocedure cardiac magnetic resonance imaging in providing invaluable information that allowed detailed planning of a management strategy for this unusual pseudoaneurysm. © 2014 Wiley Periodicals, Inc. PMID:24824727

Srivastava, Nayan T; Hoyer, Mark H

2015-02-01

212

A hammock in the left atrium.  

PubMed

Shone's anomaly describes a complex involving multiple left sided cardiac obstructions, namely, parachute deformity of the mitral valve, supravalvular ring of the left atrium, subaortic stenosis and aortic coarctation. We are reporting a case of Shone's anomaly characterised by aortic recoarctation, mitral supravalvular membrane, bicuspid aortic valve, complicated complete atrioventricular block and bradycardia-induced nonsustained polymorphic ventricular tachycardia. We revealed mitral supravalvular membrane by 3D transoesophageal echocardiography. PMID:21316305

Guler, Ahmet; Aung, Soe Moe; Kargin, Ramazan; Bitigen, Atilla; Ozdemir, Nihal

2011-08-01

213

Portable Hyperbaric Chamber  

NASA Technical Reports Server (NTRS)

A portable, collapsible hyperbaric chamber was developed. A toroidal inflatable skeleton provides initial structural support for the chamber, allowing the attendant and/or patient to enter the chamber. Oval hatches mate against bulkhead rings, and the hyperbaric chamber is pressurized. The hatches seal against an o-ring, and the internal pressure of the chamber provides the required pressure against the hatch to maintain an airtight seal. In the preferred embodiment, the hyperbaric chamber has an airlock to allow the attendant to enter and exit the patient chamber during treatment. Visual communication is provided through portholes in the patient and/or airlock chamber. Life monitoring and support systems are in communication with the interior of the hyperbaric chamber and/or airlock chamber through conduits and/or sealed feed-through connectors into the hyperbaric chamber.

Schneider, William C. (Inventor); Locke, James P. (Inventor); DeLaFuente, Horacio (Inventor)

2001-01-01

214

Congenital left ventricular diverticulum: Multimodality imaging evaluation and literature review.  

PubMed

Congenital ventricular diverticulum is a rare cardiac malformation. We present the case of a 57-year-old man who underwent cardiac catheterization for suspected unstable angina. No coronary artery disease was diagnosed and a left ventricular diverticulum was incidentally found. Coronary CT and cardiac MRI were performed in order to confirm the diagnosis of a muscular type diverticulum and to exclude a post-ischemic aneurysm. PMID:25544824

Romagnoli, Andrea; Ricci, Aurora; Morosetti, Daniele; Fusco, Armando; Citraro, Daniele; Simonetti, Giovanni

2015-01-01

215

Congenital left ventricular diverticulum: Multimodality imaging evaluation and literature review  

PubMed Central

Congenital ventricular diverticulum is a rare cardiac malformation. We present the case of a 57-year-old man who underwent cardiac catheterization for suspected unstable angina. No coronary artery disease was diagnosed and a left ventricular diverticulum was incidentally found. Coronary CT and cardiac MRI were performed in order to confirm the diagnosis of a muscular type diverticulum and to exclude a post-ischemic aneurysm. PMID:25544824

Romagnoli, Andrea; Ricci, Aurora; Morosetti, Daniele; Fusco, Armando; Citraro, Daniele; Simonetti, Giovanni

2014-01-01

216

Malignant Arrhythmia with Benign Tumour: Fibrolipoma of the Left Ventricle  

PubMed Central

We report a case of young male referred for evaluation of recent onset recurrent syncope. Inhospital electrocardiogram revealed an episode of ventricular flutter which reverted spontaneously to sinus rhythm. Transthoracic echocardiogram showed hyperechoic mass in the left ventricle. For further tissue characterization a cardiac magnetic resonance imaging was done which revealed a left ventricular mass with predominant fat content. The tumor was surgically resected. Histopathological examination confirmed the diagnosis of cardiac fibrolipoma. The patient recovered and is currently asymptomatic. PMID:25309694

Sajeev, Chakanalil Govindan; Nair, Anishkumar; Muneer, Kader; Rajesh, Gopalan Nair; Deshabandhu, Vinayakumar; Subramaniam, Gomathy; Pillai, Rajesh Sadanandan; Kuriakose, Kudakkachira Mathew; Krishnan, Mangalath Narayanan

2014-01-01

217

Resveratrol ameliorates cardiac dysfunction induced by pressure overload in rats via structural protection and modulation of Ca 2+ cycling proteins.  

PubMed

BackgroundCardiac hypertrophy is a compensatory stage of the heart in response to stress such as pressure overload (PO), which can develop into heart failure (HF) if left untreated. Resveratrol has been reported to prevent the development of hypertrophy and contractile dysfunction induced by PO. However, other studies found that resveratrol treatment for a longer period of time failed to regress cardiac hypertrophy. The aim of this study is to determine the timing of resveratrol treatment to achieve antihypertrophic effect and investigate whether resveratrol prevents the development of HF through preservation of myocardium structure and modulation of Ca2+ handling proteins.MethodsTo generate rats with cardiac hypertrophy, male Sprague¿Dawley rats were subjected to PO (aortic banding procedure) for 4 weeks. Sham-operated animals served as controls. Rats with cardiac hypertrophy were given resveratrol (4 mg/kg/day) for 4, 6, and 8 weeks, respectively. Histological and echocardiographic analysis and transmission electron microscopy were performed to assess cardiac structure and function. The levels of Ca2+ handling proteins were measured by western blot analysis.ResultsHistological analysis showed that resveratrol treatment regressed developed cardiac hypertrophy at 8 and 10 weeks postsurgery, but not at 12 weeks. However, resveratrol strongly and continuously prevented the development of cardiac dysfunction and dilation of cardiac chamber as evaluated by echocardiography and H&E staining of heart cross-sections. In addition, PO-induced cardiac fibrosis was completely inhibited by resveratrol treatment. Resveratrol markedly prevented the disrupted myocardium but partially rescued mitochondrial abnormality in banded rats. Moreover, resveratrol prevented the alteration of Ca2+ handling proteins induced by aortic banding, including downregulation of sarcoplasmic reticulum Ca2+ ATPase 2 (SERCA2) and ryanodine receptor 2 (RyR2), hypophosphorylated phospholamban (PLB), upregulation of Na+/Ca2+-exchangers (NCX1) and increased expression and phosphorylation of Ca2+/calmodulin -dependent protein kinase II (CaMKII). Moreover, resveratrol alleviated the decreased SERCA activity induced by aortic banding.ConclusionsResveratrol effectively prevented the transition from compensatory to decompensatory stage of cardiac hypertrophy induced by PO, but this effect is dependent on the timing of treatment. We suggest that resveratrol may exert beneficial effects on cardiac hypertrophy through protection of cardiac structure and modulation of Ca2+ handling proteins. PMID:25425099

Dong, Qi; Wu, Zhiye; Li, Xiaoyun; Yan, Jianyun; Zhao, Luning; Yang, Chuntao; Lu, Junjiang; Deng, Ju; Chen, Minsheng

2014-11-26

218

Heart failure caused by congenital left-sided lesions.  

PubMed

There are diverse mechanisms by which congenital left-sided cardiac lesions can precipitate heart failure. Left heart outflow obstruction can impose abnormal pressure load on the left ventricle, inducing adverse remodeling, hypertrophy, and diastolic and systolic dysfunction. Abnormalities in left ventricular inflow can increase pulmonary venous pressure and predisposing to pulmonary edema. In addition, inborn abnormalities in left ventricular myocardial structure and function can impair both systolic and diastolic function and manifest as heart failure later in life. In this article, the different mechanisms, outcomes, and treatments of heart failure in patients with congenital left-sided lesions are discussed. PMID:24275301

Krieger, Eric V; Fernandes, Susan M

2014-01-01

219

Cardiac factors in orthostatic hypotension  

NASA Astrophysics Data System (ADS)

Cardiac function is determined by preload, afterload, heart rate and contractility. During orthostatic stress, the footward blood shift is compensated for by an increase of afterload. LBNP is widely used to analyze effects of volume displacement during orthostatic stress. Comparisons of invasive ( right heart catheterization) and non-invasive approach (echocardiography) yielded similar changes. Preload and afterload change with graded LBNP, heart rate increases, and stroke volume and cardiac output decrease. Thus, the working point on the left ventricular function curve is shifted to the left and downward, similar to hypovolemia. However, position on the Frank-Starling curve, the unchanged ejection fraction, and the constant Vcf indicate a normal contractile state during LBNP. A decrease of arterial oxygen partial pressure during LBNP shwos impaired ventilation/perfusion ratio. Finally, LBNP induced cardiac and hemodynamic changes can be effectively countermeasured by dihydroergotamine, a potent venoconstrictor. Comparison of floating catheter data with that of echocardiography resulted in close correlation for cardiac output and stroke volume. In addition, cardiac dimensions changed in a similar way during LBNP. From our findings, echocardiography as a non-invasive procedure can reliably used in LBNP and orthostatic stress tests. Some informations can be obtained on borderline values indicating collaps or orthostatic syncope. Early fainters can be differentiated from late fainters by stroke volume changes.

Löllgen, H.; Dirschedl, P.; Koppenhagen, K.; Klein, K. E.

220

Cardiac Arrest  

MedlinePLUS

... or it can stop beating. Sudden cardiac arrest (SCA) occurs when the heart develops an arrhythmia that ... is blocked. There are many possible causes of SCA. They include coronary heart disease, physical stress, and ...

221

Cardiac Paragangliomas.  

PubMed

Cardiac paraganglioma is a rare entity. We review the clinical data from 158 patients reported in 132 isolated papers, and discuss clinical presentations, imaging findings, pathology, location, therapy, and outcomes. PMID:25331372

Wang, Ji-Gang; Han, Jing; Jiang, Tao; Li, Yu-Jun

2014-10-20

222

Cardiac Catheterization  

MedlinePLUS

... done during a cardiac catheterization include: closing small holes inside the heart repairing leaky or narrow heart ... bandage. It's normal for the site to be black and blue, red, or slightly swollen for a ...

223

Robotic left ventricular epicardial lead positioning.  

PubMed

Cardiac resynchronization therapy is indicated in advanced heart failure patients with a wide QRS complex, because it restores the synchronicity of the atrioventricular, interventricular and intraventricular contractions. It is performed through endovascular implantation of one or more leads. Left cardiac lead positioning is one of the most challenging procedures in interventional cardiology; unfortunately, in up to 40% of cases no clinical improvements occur. Surgical implantation of a left ventricular lead is indicated in cases of failure or predicted unfeasibility of a transvenous positioning. Several surgical techniques have been described for implantation of left ventricular lead. Minimally invasive approaches, including video-assisted thoracic and robotic surgery, are favoured due to reduced trauma, pain and recovery time. Robotic surgery confers significant advantages for visualization and manoeuverability, which are important in patients with a history of cardiac surgery, in whom scarring and adhesions may render placement challenging. We describe here the surgical technique for robotic implantation of left ventricular leads in candidates for cardiac resynchronization therapy. PMID:25564506

Loddo, Paolo; Sionis, Carla; Schintu, Barbara; Paliogiannis, Panagiotis

2015-01-01

224

Adenovirus-mediated delivery of relaxin reverses cardiac fibrosis.  

PubMed

We have evaluated the effectiveness of systemic adenovirally delivered mouse relaxin on reversing fibrosis in a transgenic murine model of fibrotic cardiomyopathy due to beta(2)-adrenergic receptor (beta(2)AR) overexpression. Recombinant adenoviruses expressing green fluorescent protein (Ad-GFP), rat relaxin (Ad-rRLN) and mouse relaxin (Ad-mRLN) were generated and Ad-rRLN and Ad-mRLN were demonstrated to direct the expression of bioactive relaxin peptides in vitro. A single systemic injection of Ad-mRLN resulted in transgene expression in the liver and bioactive relaxin peptide in the plasma. Ad-mRLN, but not Ad-GFP, treatment reversed the increased left ventricular collagen content in beta(2)AR mice to control levels without affecting collagen levels in other heart chambers or in the lung and kidney. Hence a single systemic injection of adenovirus producing mouse relaxin reverses cardiac fibrosis without adversely affecting normal collagen levels in other organs and establishes the potential for the use of relaxin gene therapy for the treatment of cardiac fibrosis. PMID:17961912

Bathgate, R A D; Lekgabe, E D; McGuane, J T; Su, Y; Pham, T; Ferraro, T; Layfield, S; Hannan, R D; Thomas, W G; Samuel, C S; Du, X-J

2008-01-01

225

7. SEDIMENTATION CHAMBER AT 520', CONSTRUCTED 19371938, VIEWED FROM DOWNSTREAM. ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

7. SEDIMENTATION CHAMBER AT 520', CONSTRUCTED 1937-1938, VIEWED FROM DOWNSTREAM. DEBRIS REMOVED FROM TOP PLANKS FOR CLARITY. ONE OF TWO SPILLWAYS SEEN AT RIGHT. FLUSH VALVE SEEN AT LOWER LEFT AND WRENCH FOR VALVES IS PROPPED AGAINST CHAMBER. - Kalaupapa Water Supply System, Waikolu Valley to Kalaupapa Settlement, Island of Molokai, Kalaupapa, Kalawao County, HI

226

Segmentation of the Left Heart Ventricle in Ultrasound Images Using a Region Based Snake  

E-print Network

Segmentation of the Left Heart Ventricle in Ultrasound Images Using a Region Based Snake Matilda that uses a region based snake. To avoid any unwanted concavities in the segmentations due to the cardiac valve we use two anchor points in the snake that are located to the left and to the right of the cardiac

Lunds Universitet

227

Origin of Cardiac Fibroblasts and the Role of Periostin  

PubMed Central

Cardiac fibroblasts are the most populous non-myocyte cell type within the mature heart and are required for extracellular matrix synthesis and deposition, generation of the cardiac skeleton, and to electrically insulate the atria from the ventricles. Significantly, cardiac fibroblasts have also been shown to play an important role in cardiomyocyte growth and expansion of the ventricular chambers during heart development. Although there are currently no cardiac fibroblast-restricted molecular markers, it is generally envisaged that the majority of the cardiac fibroblasts are derived from the proepicardium via epithelial-to-mesenchymal transformation. However, still relatively little is known about when and where the cardiac fibroblasts cells are generated, the lineage of each cell, and how cardiac fibroblasts move to reside in their final position throughout all four cardiac chambers. In this review we summarize the current understanding regarding the function of Periostin, a useful marker of the non-cardiomyocyte lineages, and its role during cardiac morphogenesis. Characterization of the cardiac fibroblast lineage and identification of the signals that maintain, expand and regulate their differentiation will be required to improve our understanding of cardiac function in both normal and pathophysiological states. PMID:19893021

Snider, Paige; Standley, Kara N.; Wang, Jian; Azhar, Mohamad; Doetschman, Thomas; Conway, Simon J.

2009-01-01

228

A Randomized Controlled Trial to Evaluate the Safety and Efficacy of Cardiac Contractility Modulation in Patients With Moderately Reduced Left Ventricular Ejection Fraction and a Narrow QRS Duration: Study Rationale and Design.  

PubMed

Cardiac contractility modulation (CCM) signals are nonexcitatory electrical signals delivered during the cardiac absolute refractory period that enhance the strength of cardiac muscular contraction. The FIX-HF-5 study was a prospective randomized study comparing CCM plus optimal medical therapy (OMT) to OMT alone that included 428 New York Heart Association (NYHA) functional class III or IV heart failure patients with ejection fraction (EF) ?45% according to core laboratory assessment. The study met its primary safety end point, but did not reach its primary efficacy end point: a responders analysis of changes in ventilatory anaerobic threshold (VAT). However, in a prespecified subgroup analysis, significant improvements in primary and secondary end points, including the responder VAT end point, were observed in patients with EFs ranging from 25% to 45%, who constituted about one-half of the study subjects. We therefore designed a new study to prospectively confirm the efficacy of CCM in this population. A hierarchic bayesian statistical analysis plan was developed to take advantage of the data already available from the first study. In addition, based on technical difficulties encountered in reliably quantifying VAT and the relatively large amount of nonquantifiable studies, the primary efficacy end point was changed to peak VO2, with significant measures incorporated to minimize the influence of placebo effect. In this paper, we provide the details and rationale of the FIX-HF-5C study design to study CCM plus OMT compared with OMT alone in subjects with normal QRS duration, NYHA functional class III or IV, and EF 25%-45%. This study is registered on www.clinicaltrials.gov with identifier no. NCT01381172. PMID:25285748

Abraham, William T; Lindenfeld, JoAnn; Reddy, Vivek Y; Hasenfuss, Gerd; Kuck, Karl-Heinz; Boscardin, John; Gibbons, Robert; Burkhoff, Daniel

2015-01-01

229

Cardiac catheterization is underutilized after in-hospital cardiac arrest  

PubMed Central

Background Indications for immediate cardiac catheterization in cardiac arrest survivors without ST elevation myocardial infarction (STEMI) are uncertain as electrocardiographic and clinical criteria may be challenging to interpret in this population. We sought to evaluate rates of early catheterization after in-hospital ventricular fibrillation (VF) arrest and the association with survival. Methods Using a billing database we retrospectively identified cases with an ICD-9 code of cardiac arrest (427.5) or VF (427.41). Discharge summaries were reviewed to identify in-hospital VF arrests. Rates of catheterization on the day of arrest were determined by identifying billing charges. Unadjusted analyses were performed using chi square, and adjusted analyses were performed using logistic regression. Results 110 in-hospital VF arrest survivors were included in the analysis. Cardiac catheterization was performed immediately or within one day of arrest in 27% (30/110) of patients and of these patients, 57% (17/30) successfully received percutaneous coronary intervention. Of those who received cardiac catheterization the indication for the procedure was STEMI or new left bundle branch block (LBBB) in 43% (13/30). Therefore, in the absence of standard ECG data suggesting acute myocardial infarction, 57% (17/30) received angiography. Patients receiving cardiac catheterization were more likely to survive than those who did not receive catheterization (80% vs. 54%, p<.05). Conclusion In patients receiving cardiac catheterization, more than half received this procedure for indications other than STEMI or new LBBB. Cardiac catheterization was associated with improved survival. Future recommendations need to be established to guide clinicians on which arrest survivors might benefit from immediate catheterization. PMID:18951683

Merchant, Raina M.; Abella, Benjamin S.; Khan, Monica; Huang, Kuang-Ning; Beiser, David B.; Neumar, Robert W.; Carr, Brendan G.; Becker, Lance B.; Vanden Hoek, Terry L.

2009-01-01

230

12. VIEW, LOOKING SOUTH FROM LEFT TO RIGHT, SHOWING DRESSING ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

12. VIEW, LOOKING SOUTH FROM LEFT TO RIGHT, SHOWING DRESSING FROM AND WORK/CHAMBER ROOM - U.S. Naval Submarine Base, New London Submarine Escape Training Tank, Albacore & Darter Roads, Groton, New London County, CT

231

Assessment of left ventricular function: comparison between radionuclide angiography and semiquantitative two-dimensional echocardiographic analysis  

Microsoft Academic Search

Measurement of global left ventricular function is important in the follow-up of cardiac patients and is a good prognostic indicator in acute cardiac situations. We compared quantitative measurements of global left ventricular function made with radionuclide angiography (RNA) and contrast cardiac ventriculography (CVG) to visual semiquantitative estimates from two-dimensional echocardiographic images (2D-echo). Three hundred and thirty-nine consecutive patients who underwent

Michael Gottsauner-Wolf; Johanna Schedimayer-Duit; Gerold Porenta; Marianne Gwechenberger; Kurt Huber; Dietmar Giogar; Peter Probst; Heinz Sochor

1996-01-01

232

An integrated bioimpedance--ECG gating technique for respiratory and cardiac motion compensation in cardiac PET.  

PubMed

Respiratory motion may degrade image quality in cardiac PET imaging. Since cardiac PET studies often involve cardiac gating by ECG, a separate respiratory monitoring system is required increasing the logistic complexity of the examination, in case respiratory gating is also needed. Thus, we investigated the simultaneous acquisition of both respiratory and cardiac gating signals using II limb lead mimicking electrode configuration during cardiac PET scans of 11 patients. In addition to conventional static and ECG-gated images, bioimpedance technique was utilized to generate respiratory- and dual-gated images. The ability of the bioimpedance technique to monitor intrathoracic respiratory motion was assessed estimating cardiac displacement between end-inspiration and -expiration. The relevance of dual gating was evaluated in left ventricular volume and myocardial wall thickness measurements. An average 7.6? ± ?3.3?mm respiratory motion was observed in the study population. Dual gating showed a small but significant increase (4?ml, p = 0.042) in left ventricular myocardial volume compared to plain cardiac gating. In addition, a thinner myocardial wall was observed in dual-gated images (9.3? ± ?1.3?mm) compared to cardiac-gated images (11.3? ± ?1.3?mm, p = 0.003). This study shows the feasibility of bioimpedance measurements for dual gating in a clinical setting. The method enables simultaneous acquisition of respiratory and cardiac gating signals using a single device with standard ECG electrodes. PMID:25295531

Koivumäki, Tuomas; Nekolla, Stephan G; Fürst, Sebastian; Loher, Simone; Vauhkonen, Marko; Schwaiger, Markus; Hakulinen, Mikko A

2014-11-01

233

An integrated bioimpedance—ECG gating technique for respiratory and cardiac motion compensation in cardiac PET  

NASA Astrophysics Data System (ADS)

Respiratory motion may degrade image quality in cardiac PET imaging. Since cardiac PET studies often involve cardiac gating by ECG, a separate respiratory monitoring system is required increasing the logistic complexity of the examination, in case respiratory gating is also needed. Thus, we investigated the simultaneous acquisition of both respiratory and cardiac gating signals using II limb lead mimicking electrode configuration during cardiac PET scans of 11 patients. In addition to conventional static and ECG-gated images, bioimpedance technique was utilized to generate respiratory- and dual-gated images. The ability of the bioimpedance technique to monitor intrathoracic respiratory motion was assessed estimating cardiac displacement between end-inspiration and -expiration. The relevance of dual gating was evaluated in left ventricular volume and myocardial wall thickness measurements. An average 7.6? ± ?3.3?mm respiratory motion was observed in the study population. Dual gating showed a small but significant increase (4?ml, p = 0.042) in left ventricular myocardial volume compared to plain cardiac gating. In addition, a thinner myocardial wall was observed in dual-gated images (9.3? ± ?1.3?mm) compared to cardiac-gated images (11.3? ± ?1.3?mm, p = 0.003). This study shows the feasibility of bioimpedance measurements for dual gating in a clinical setting. The method enables simultaneous acquisition of respiratory and cardiac gating signals using a single device with standard ECG electrodes.

Koivumäki, Tuomas; Nekolla, Stephan G.; Fürst, Sebastian; Loher, Simone; Vauhkonen, Marko; Schwaiger, Markus; Hakulinen, Mikko A.

2014-10-01

234

[Evaluation by means of ECG-gated cardiac blood pool scintigraphy of global and regional left ventricular function at rest and during exercise in patients with coronary artery disease (author's transl)].  

PubMed

ECG-gated cardiac blood pool scintigraphy permits a non-invasive determination of the end-diastolic and end-systolic ventricular volumes and of the ejection fraction as well as a qualitative description of regional ventricular wall motion at rest and during excercise. In 6 healthy persons a significant increase of the ejection fraction from 66 +/- 7% at rest to 78 +/- 3% during exercise (p less than 0.01) was observed. In contrast, the ejection fraction decreased in 15 out of 18 patients with coronary artery disease, with a significant (p less than 0.01) difference between patients with and without angina pectoris. Thus, the ejection fraction fell in 12 patients without angina during excercise from 60 +/- 11% to 52 +/- 11% (p less than 0.05) whereas in 6 patients with angina a decrease from 61 +/- 7% to 30 +/- 8% (p less than 0.01) was observed. This non-invasive technique makes it possible to demonstrate in a simple and safe manner changes of cardiac function during excercise in patients with coronary artery disease. PMID:733592

Sauer, E; Sebening, H; Lutilsky, L; Dressler, H; Hör, G; Pabst, H W; Blömer, H

1978-10-01

235

An Unusual Biatrial Cardiac Myxoma in a Young Patient  

PubMed Central

This is a report of a biatrial cardiac myxoma in a young man with a 10-month history of exertional dyspnea and palpitation. The echocardiogram revealed biatrial myxoma prolapsing through the mitral and tricuspid valves during diastole. All cardiac chambers were enlarged and dysfunctional. The electrocardiogram revealed a rapid ventricular response with atrial flutter rhythm. The masses were resected and diagnosed as myxoma by a histological examination. The follow-up echocardiogram revealed significant improvement in ventricular function and reduction in the cardiac chambers’ volume. There was no evidence of myxoma recurrence. The most probable cause of the patient’s heart failure was considered to be tachycardia-induced cardiomyopathy.

Azari, Ali; Moravvej, Zahra; Chamanian, Soheila; Bigdelu, Leila

2015-01-01

236

Abnormal Origin of the Left Subclavian Artery from the Left Pulmonary Artery in a Patient with Double Outlet Right Ventricle  

PubMed Central

Anomalous aortic origin of the left subclavian artery (LSCA) from the left pulmonary artery (LPA) is a rare congenital cardiac malformation. We describe a case of LSCA from the LPA via ductus arteriosus in association with a double-outlet right ventricle, which never has been reported previously in Korea. PMID:24570863

Hong, Seong Wook

2014-01-01

237

What type of different clinical manifestations can cardiac sarcoidosis present?  

PubMed

Cardiac sarcoidosis is an infiltrative, granulomatous inflammatory disease of the myocardium. Generally, it can be difficult to diagnose cardiac sarcoidosis clinically because of the non-specific nature of its clinical manifestations. This property can be based on the presence of any clinical evidence of sarcoidosis in the other organs. We present two cases of cardiac sarcoidosis so as to demonstrate its different clinical manifestations. The first patient displayed no cardiac symptoms; the electrocardiogram showed an incidental right bundle branch block. Her cardiac magnetic resonance imaging (CMRI) revealed late-phase opaque material enhancement involving the inferior and inferoseptal segment of the left ventricle. The second patient was severely symptomatic in terms of cardiac involvement, and a transthoracic echocardiogram revealed global hypokinesia and septal brightness; his ejection fraction decreased to 45 %. These cases highlighted the challenges encountered in the diagnosis and treatment of cardiac sarcoidosis. CMRI should be considered in all patients who have suspected findings for cardiac involvement. PMID:25429793

Sentürk, Ay?egül; Mara?, Yüksel; Argüder, Emine; Karalezli, Ay?egül; Hasano?lu, H Canan; O?üt, Tuba; Ba?tu?, Serdal; Karabekir, Ercan

2014-11-28

238

Radionuclide left ventricular dV\\/dt for the assessment of cardiac function in patients with coronary disease. [\\/sup 99m\\/Ic-labelled red blood cells and contrast radiography  

Microsoft Academic Search

To investigate potential uses of left-ventricular (LV) systolic ejection rate (LV dV\\/dt) in the evaluation of LV function, we examined the effect of exercise, angiotensin, and leg raising on LV ejection fraction and LV dV\\/dt in patients with coronary-artery disease. The following observations were made: (a) LV ejection fraction and dV\\/dt changed proportionately, but in opposite directions, during supine exercise;

J. A. Bianco; D. G. Makey; W. K. Laskey; R. B. Shafer

1979-01-01

239

Two chamber reaction furnace  

DOEpatents

A vertical two chamber reaction furnace is described. The furnace comprises a lower chamber having an independently operable first heating means for heating the lower chamber and a gas inlet means for admitting a gas to create an ambient atmosphere, and an upper chamber disposed above the lower chamber and having an independently operable second heating means for heating the upper chamber. Disposed between the lower chamber and the upper chamber is a vapor permeable diffusion partition. The upper chamber has a conveyor means for conveying a reactant there through. Of particular importance is the thallinating of long-length thallium-barium-calcium-copper oxide (TBCCO) or barium-calcium-copper oxide (BCCO) precursor tapes or wires conveyed through the upper chamber to thereby effectuate the deposition of vaporized thallium (being so vaporized as the first reactant in the lower chamber at a temperature between about 700 C and 800 C) on TBCCO or BCCO tape or wire (the second reactant) at its simultaneous annealing temperature in the upper chamber of about 800 to 950 C to thereby replace thallium oxide lost from TBCCO tape or wire because of the high annealing temperature or to deposit thallium on BCCO tape or wire. Continuously moving the tape or wire provides a single-step process that effectuates production of long-length TBCCO superconducting product. 2 figs.

Blaugher, R.D.

1998-05-05

240

Hyperphysics: The Cloud Chamber  

NSDL National Science Digital Library

This Hyperphysics webpage contains a short description of the Wilson cloud chamber and two photographs by Wilson himself of cloud chamber tracks. Links provides information about various methods of detecting radiation and also about the muon, an elementary particle that was first detected in a cloud chamber. The text on this page is written at a level of a student of introductory physics.

Nave, Carl R.

2008-11-26

241

Impaired contractile function due to decreased cardiac myosin binding protein C content in the sarcomere.  

PubMed

Mutations in cardiac myosin binding protein C (MyBP-C) are a common cause of familial hypertrophic cardiomyopathy (FHC). The majority of MyBP-C mutations are expected to reduce MyBP-C expression; however, the consequences of MyBP-C deficiency on the regulation of myofilament function, Ca²? homeostasis, and in vivo cardiac function are unknown. To elucidate the effects of decreased MyBP-C expression on cardiac function, we employed MyBP-C heterozygous null (MyBP-C+/-) mice presenting decreases in MyBP-C expression (32%) similar to those of FHC patients carrying MyBP-C mutations. The levels of MyBP-C phosphorylation were reduced 53% in MyBP-C+/- hearts compared with wild-type hearts. Skinned myocardium isolated from MyBP-C+/- hearts displayed decreased cross-bridge stiffness at half-maximal Ca²? activations, increased steady-state force generation, and accelerated rates of cross-bridge recruitment at low Ca²? activations (<15% and <25% of maximum, respectively). Protein kinase A treatment abolished basal differences in rates of cross-bridge recruitment between MyBP-C+/- and wild-type myocardium. Intact ventricular myocytes from MyBP-C+/- hearts displayed abnormal sarcomere shortening but unchanged Ca²? transient kinetics. Despite a lack of left ventricular hypertrophy, MyBP-C+/- hearts exhibited elevated end-diastolic pressure and decreased peak rate of LV pressure rise, which was normalized following dobutamine infusion. Furthermore, electrocardiogram recordings in conscious MyBP-C+/- mice revealed prolonged QRS and QT intervals, which are known risk factors for cardiac arrhythmia. Collectively, our data show that reduced MyBP-C expression and phosphorylation in the sarcomere result in myofilament dysfunction, contributing to contractile dysfunction that precedes compensatory adaptations in Ca²? handling, and chamber remodeling. Perturbations in mechanical and electrical activity in MyBP-C+/- mice could increase their susceptibility to cardiac dysfunction and arrhythmia. PMID:23666674

Cheng, Y; Wan, X; McElfresh, T A; Chen, X; Gresham, K S; Rosenbaum, D S; Chandler, M P; Stelzer, J E

2013-07-01

242

Evaluation of Carbon Dioxide Dissipation within a Euthanasia Chamber  

PubMed Central

CO2 euthanasia is used widely for small laboratory animals, such as rodents. A common necessity in many animal research facilities is to euthanize mice in sequential batches. We assessed the effects of several variables on the time it took for CO2 to dissipate within a chamber. Using standard euthanasia time, changes in flow rate were compared between a slow 15% fill rate for 7 min, and a slow 15% followed by a rapid 50% filling for a total of 5 min. Additional variables assessed included the effects of opening the lid after the completion of chamber filling, turning the chamber over after completion of filling, and the use and removal of a cage from within the chamber. For all trials, CO2 levels in the chambers peaked between 50% and 80%. After the gas was turned off, the concentration of CO2 dropped to below 10% CO2 within 2 min, except when the lid was left on the chamber, where concentration levels remained above 10% after 20 min. CO2 dissipation was significantly faster when the chamber was turned upside down after filling. Significant interaction effects occurred among the factors of cage presence within the chamber, flow rate, and chamber position. Only leaving the lid on the chamber had any practical implication for delaying CO2 dissipation. We recommend that users allow 2 min for CO2 to clear from the chamber before subsequent euthanasia procedures, unless the chamber is manipulated to increase the dissipation rate. PMID:25199098

Djoufack-Momo, Shelly M; Amparan, Ashlee A; Grunden, Beverly; Boivin, Gregory P

2014-01-01

243

Stove with multiple chambers  

SciTech Connect

A stove is described for burning a solid fuel such as wood. The wall means defines a main air inlet, a combustion gas outlet, and four chambers through which gas passes sequentially from the main air inlet to the combustion gas outlet. The chambers comprises a pre-heat plenum chamber into which the main air inlet opens. A main combustion chamber contains solid fuel to be burned into which gas passes from the pre-heat plenum chamber, a second combustion chamber which is downstream of the main combustion chamber with respect to the flow of gas from the main air inlet to the combustion gas outlet, and a third combustion chamber from which the combustion gas outlet opens. The stove also comprises a plate having a restricted opening for providing communication between the second and third combustion chambers. And a catalytic converter comprises a body of solid material formed with passageways, the body of solid material being fitted in the restricted opening so that gas passes from the second combustion chamber to the third combustion chamber by way of the passageways in the body.

Black, A.

1987-04-21

244

Contour extraction from cardiac MRI studies using snakes  

Microsoft Academic Search

The author investigated automatic extraction of left ventricular contours from cardiac magnetic resonance imaging (MRI) studies. The contour extraction algorithms were based on active contour models, or snakes. Based on cardiac MR image characteristics, the author suggested algorithms for extracting contours from these large data sets. The author specifically considered contour propagation methods to make the contours reliable enough despite

Surendra Ranganath

1995-01-01

245

Cardiac Circulation  

NSDL National Science Digital Library

This simple FlashTM animation depicts blood flow through the great vessels and chambers of the mature heart. Clicking brings up labels. A second click brings up arrows defining venous flow. A third click brings up arrows tracing the arterial flow.

PhD Jack D Thatcher (West Virginia School of Osteopathic Medicine Structural Biology)

2009-11-20

246

Isolated right superior vena cava drainage into the left atrium diagnosed noninvasively in the peripartum period.  

PubMed

Isolated right superior vena cava drainage into the left atrium is an extremely rare cardiac anomaly, especially in the absence of other cardiac abnormalities. Only 28 of 5,127 reported consecutive congenital cardiac cases involved superior vena cava drainage into the left atrium, and all were associated with other cardiac anomalies. Of 19 reported cases of right superior vena cava drainage into the left atrium, most patients have been children who were experiencing mild hypoxemia and cyanosis. Herein, we describe the case of a 34-year-old woman who presented with asymptomatic hypoxemia in the peripartum period. She was diagnosed to have isolated drainage of the right superior vena cava into the left atrium. To the best of our knowledge, this is the 1st reported instance of such diagnosis by use of noninvasive imaging only, without cardiac catheterization. We also review the medical literature that pertains to our patient's anomaly. PMID:20069093

Baggett, Charles; Skeen, Shawn J; Gantt, D Scott; Trotter, Bradley R; Birkemeier, Krista L

2009-01-01

247

Cardiac sarcoidosis.  

PubMed

The prognosis of sarcoidosis often considered as "benign" is significantly changed in the presence of a cardiac localization. An in-depth interview, a clinical examination together with ECG are often for most of sarcoidosis. Certain conditions (severe multisystemic sarcoidosis, rares localizations in particular neurological, renal, gastric) lead to necessary investigations: Holter ECG, echocardiography, thallium scintigraphy with dipyridamole test, PET scanner and MRI in order to identify infraclinical presentations. Diagnosis relies on guidelines of Japansese criteria, but can benefit from MRI and PET scanner even though their place is not yet clearly defined in clinical pratice. Diagnosing cardiac sarcoidosis means deciding an immunosuppressive treatment. It is highly important to gather all criteria to validate a consistent diagnosis or at least a high probability. In order to best adapt therapy, a coordinated patient care involving the cardiologist and the sarcoidosis specialist is necessary. PMID:22608949

Chapelon-Abric, Catherine

2012-06-01

248

Homogeneity of Cardiac Contraction Despite Physiological Asynchrony of Depolarization: A Model Study  

Microsoft Academic Search

The use of mathematical models combining wave propagation and wall mechanics may provide new insights in the interpretation of cardiac deformation toward various forms of cardiac pathology. In the present study we investigated whether combining accepted mechanisms on propagation of the depolarization wave, time variant mechanical properties of cardiac tissue after depolarization, and hemodynamic load of the left ventricle (LV)

R. C. P. Kerckhoffs; P. H. M. Bovendeerd; J. C. S. Kotte; F. W. Prinzen; K. Smits; T. Arts

2003-01-01

249

Cardiac nociceptive reflexes after transmyocardial laser revascularization: Implications for the neural hypothesis of angina relief  

Microsoft Academic Search

Objective: The mechanism by which transmyocardial laser revascularization relieves angina is not understood. One theory is that laser-induced thermal damage to cardiac nerves results in cardiac denervation. This study examined the acute effects of transmyocardial laser revascularization on reflex responses mediated by cardiac nociceptors, the left ventricular receptors with sympathetic afferent fibers that are thought to mediate anginal chest pain.

Anthony J. Minisi; On Topaz; M. Susan Quinn; Laxmi B. Mohanty

2001-01-01

250

Cardiac optogenetics  

PubMed Central

Optogenetics is an emerging technology for optical interrogation and control of biological function with high specificity and high spatiotemporal resolution. Mammalian cells and tissues can be sensitized to respond to light by a relatively simple and well-tolerated genetic modification using microbial opsins (light-gated ion channels and pumps). These can achieve fast and specific excitatory or inhibitory response, offering distinct advantages over traditional pharmacological or electrical means of perturbation. Since the first demonstrations of utility in mammalian cells (neurons) in 2005, optogenetics has spurred immense research activity and has inspired numerous applications for dissection of neural circuitry and understanding of brain function in health and disease, applications ranging from in vitro to work in behaving animals. Only recently (since 2010), the field has extended to cardiac applications with less than a dozen publications to date. In consideration of the early phase of work on cardiac optogenetics and the impact of the technique in understanding another excitable tissue, the brain, this review is largely a perspective of possibilities in the heart. It covers the basic principles of operation of light-sensitive ion channels and pumps, the available tools and ongoing efforts in optimizing them, overview of neuroscience use, as well as cardiac-specific questions of implementation and ideas for best use of this emerging technology in the heart. PMID:23457014

2013-01-01

251

Left atrial distension and intrarenal blood flow distribution in conscious dogs  

Microsoft Academic Search

Measurements were made with radioactive microspheres of the distribution of renal blood flow in conscious dogs during left atrial distension. Urine volume, sodium excretion, mean arterial blood pressure and heart rate increased during the 60 min period of left atrial distension (increase in left atrial pressure by about 1.0 kPa). Total renal blood flow and cardiac output (electromagnetic flowmeters) did

G. Kaczmarczyk; V. Unger; R. Mohnhaupt; H. W. Reinhardt

1981-01-01

252

Increase in cardiac myosin heavy-chain (MyHC) alpha protein isoform in hibernating ground squirrels, with echocardiographic visualization of ventricular wall hypertrophy and prolonged contraction.  

PubMed

Deep hibernators such as golden-mantled ground squirrels (Callospermophilus lateralis) have multiple challenges to cardiac function during low temperature torpor and subsequent arousals. As heart rates fall from over 300 beats min(-1) to less than 10, chamber dilation and reduced cardiac output could lead to congestive myopathy. We performed echocardiography on a cohort of individuals prior to and after several months of hibernation. The left ventricular chamber exhibited eccentric and concentric hypertrophy during hibernation and thus calculated ventricular mass was ~30% greater. Ventricular ejection fraction was mildly reduced during hibernation but stroke volumes were greater due to the eccentric hypertrophy and dramatically increased diastolic filling volumes. Globally, the systolic phase in hibernation was ~9.5 times longer, and the diastolic phase was 28× longer. Left atrial ejection generally was not observed during hibernation. Atrial ejection returned weakly during early arousal. Strain echocardiography assessed the velocity and total movement distance of contraction and relaxation for regional ventricular segments in active and early arousal states. Myocardial systolic strain during early arousal was significantly greater than the active state, indicating greater total contractile movement. This mirrored the increased ventricular ejection fraction noted with early arousal. However, strain rates were slower during early arousal than during the active period, particularly systolic strain, which was 33% of active, compared with the rate of diastolic strain, which was 67% of active. As heart rate rose during the arousal period, myocardial velocities and strain rates also increased; this was matched closely by cardiac output. Curiously, though heart rates were only 26% of active heart rates during early arousal, the cardiac output was nearly 40% of the active state, suggesting an efficient pumping system. We further analyzed proportions of cardiac myosin heavy-chain (MyHC) isoforms in a separate cohort of squirrels over 5 months, including time points before hibernation, during hibernation and just prior to emergence. Hibernating individuals were maintained in both a 4°C cold room and a 20°C warm room. Measured by SDS-PAGE, relative percentages of cardiac MyHC alpha were increased during hibernation, at both hibernacula temperatures. A potential increase in contractile speed, and power, from more abundant MyHC alpha may aid force generation at low temperature and at low heart rates. Unlike many models of cardiomyopathies where the alpha isoform is replaced by the beta isoform in order to reduce oxygen consumption, ground squirrels demonstrate a potential cardioprotective mechanism to maintain cardiac output during torpor. PMID:24072796

Nelson, O Lynne; Rourke, Bryan C

2013-12-15

253

Increase in cardiac myosin heavy-chain (MyHC) alpha protein isoform in hibernating ground squirrels, with echocardiographic visualization of ventricular wall hypertrophy and prolonged contraction  

PubMed Central

SUMMARY Deep hibernators such as golden-mantled ground squirrels (Callospermophilus lateralis) have multiple challenges to cardiac function during low temperature torpor and subsequent arousals. As heart rates fall from over 300 beats min?1 to less than 10, chamber dilation and reduced cardiac output could lead to congestive myopathy. We performed echocardiography on a cohort of individuals prior to and after several months of hibernation. The left ventricular chamber exhibited eccentric and concentric hypertrophy during hibernation and thus calculated ventricular mass was ~30% greater. Ventricular ejection fraction was mildly reduced during hibernation but stroke volumes were greater due to the eccentric hypertrophy and dramatically increased diastolic filling volumes. Globally, the systolic phase in hibernation was ~9.5 times longer, and the diastolic phase was 28× longer. Left atrial ejection generally was not observed during hibernation. Atrial ejection returned weakly during early arousal. Strain echocardiography assessed the velocity and total movement distance of contraction and relaxation for regional ventricular segments in active and early arousal states. Myocardial systolic strain during early arousal was significantly greater than the active state, indicating greater total contractile movement. This mirrored the increased ventricular ejection fraction noted with early arousal. However, strain rates were slower during early arousal than during the active period, particularly systolic strain, which was 33% of active, compared with the rate of diastolic strain, which was 67% of active. As heart rate rose during the arousal period, myocardial velocities and strain rates also increased; this was matched closely by cardiac output. Curiously, though heart rates were only 26% of active heart rates during early arousal, the cardiac output was nearly 40% of the active state, suggesting an efficient pumping system. We further analyzed proportions of cardiac myosin heavy-chain (MyHC) isoforms in a separate cohort of squirrels over 5 months, including time points before hibernation, during hibernation and just prior to emergence. Hibernating individuals were maintained in both a 4°C cold room and a 20°C warm room. Measured by SDS-PAGE, relative percentages of cardiac MyHC alpha were increased during hibernation, at both hibernacula temperatures. A potential increase in contractile speed, and power, from more abundant MyHC alpha may aid force generation at low temperature and at low heart rates. Unlike many models of cardiomyopathies where the alpha isoform is replaced by the beta isoform in order to reduce oxygen consumption, ground squirrels demonstrate a potential cardioprotective mechanism to maintain cardiac output during torpor. PMID:24072796

Nelson, O. Lynne; Rourke, Bryan C.

2013-01-01

254

Left ventricular function studied with MDCT  

Microsoft Academic Search

Accurate determination of left ventricular (LV) myocardial function is fundamental for clinical diagnosis, risk stratification, and estimation of prognosis in patients with ischemic and nonischemic cardiomyopathy. Primarily, multi-detector-row spiral CT (MDCT) of the heart aimed at detecting coronary artery obstruction and cardiac morphology. Multiple studies have demonstrated that retrospectively, ECG-gated MDCT determination of LV volumes and consequently global LV function

Kai Uwe Juergens; Roman Fischbach

2006-01-01

255

Combined coronary and late-enhanced multidetector-computed tomography for delineation of the etiology of left ventricular dysfunction: comparison with coronary angiography and contrast-enhanced cardiac magnetic resonance imaging  

PubMed Central

Aims To evaluate whether comprehensive evaluation of coronary anatomy and delayed enhancement (DE) by multidetector-computed tomography (MDCT) would allow determination of etiology of left ventricular dysfunction (LVD) as compared with coronary angiography (CA) and DE-magnetic resonance (CMR). Methods and results Seventy-one consecutive patients (50 males, 59 ± 16 years) with LVD (ejection fraction: 26 ± 11%) of unknown etiology underwent MDCT, LGE (late Gd-DTPA-enhanced)-CMR and CA. Patients were classified into four groups according to coronary artery disease (CAD) by CA and LGE-CMR patterns. Patients (n = 24) with CAD and transmural or sub-endocardial DE by CMR were considered having definite ischaemic LVD (group 1). Patients (n = 36) without CAD by CA and with no/atypical LGE-CMR were considered non-ischaemic LVD (group 2). Further we identified four patients with transmural DE but no CAD (group 3) and seven patients with CAD but no DE (group 4). On per-patient basis, combined coronary and DE-MDCT had excellent agreement (? = 0.89; P < 0.001) with CA/LGE-CMR to classify patients into the same four groups. Sensitivity, specificity and accuracy of MDCT were 97, 92 and 94%, respectively for detecting patients with definite (group 1) or likely (groups 3 and 4) ischaemic LVD. Conclusion Combined coronary and DE-MDCT can accurately differentiate ischaemic vs. non-ischaemic etiology of LVD. PMID:18762553

le Polain de Waroux, Jean-Benoît; Pouleur, Anne-Catherine; Goffinet, Céline; Pasquet, Agnès; Vanoverschelde, Jean-Louis; Gerber, Bernhard L.

2008-01-01

256

High resolution drift chambers  

SciTech Connect

High precision drift chambers capable of achieving less than or equal to 50 ..mu..m resolutions are discussed. In particular, we compare so called cool and hot gases, various charge collection geometries, several timing techniques and we also discuss some systematic problems. We also present what we would consider an ''ultimate'' design of the vertex chamber. 50 refs., 36 figs., 6 tabs.

Va'vra, J.

1985-07-01

257

Multidetector CT and MR Imaging of Cardiac Tumors  

PubMed Central

The purpose of this article is to provide a current review of the spectrum of multidetector CT (MDCT) and MRI findings for a variety of cardiac neoplasms. In the diagnosis of cardiac tumors, the use of MDCT and MRI can help differentiate benign from malignant masses. Especially, the use of MDCT is advantageous in providing anatomical information and MRI is useful for tissue characterization of cardiac masses. Knowledge of the characteristic MRI findings of benign cardiac tumors or thrombi can be helpful to avoid unnecessary surgical procedures. Presurgical assessment of malignant cardiac tumors with the use of MDCT and MRI may allow determination of the resectability of tumors and planning for the reconstruction of cardiac chambers. PMID:19270863

Kim, Eun Young; Sung, Kiick; Park, Seung Woo; Kim, Ji Hye; Ko, Young-Hyeh

2009-01-01

258

Intrinsic Myoarchitectural Differences Between the Left and Right Ventricles of Fetal Human Hearts: An Ultrasonic Backscatter Feasibility Study  

PubMed Central

Summary Embryologically, cardiac chambers differ in their morphological and contractile properties from the beginning. We hypothesized that a non-invasive ultrasonic backscatter investigation might illustrate the fundamental differences in myocardial morphologic properties of the two ventricles during heart development. Objectives The goals of this investigation were: 1) to explore the feasibility of measuring the magnitude of cyclic variation of ultrasonic backscatter from the left and right ventricular free walls of fetal hearts; 2) to compare measurements of the magnitude of cyclic variation from the left and right sides of the heart; and 3) to determine if the observed results are consistent with predictions relating the overall backscatter level and the magnitude of cyclic variation. Methods Cyclic variation data from the left and right ventricular free walls were generated from analyses of the backscatter from echocardiographic images of 16 structurally normal fetal hearts at mid-gestation. Results The magnitude of cyclic variation was found to be greater for the left ventricular free wall than for the right ventricular free wall (4.5 ± 1.1 dB vs. 2.3 ± 0.9 dB, respectively; mean ± SD; p < 0.0001, paired t-test). Conclusion Measurements of the cyclic variation of backscatter can be obtained from both the left and right sides of fetal hearts demonstrating a significant difference between the measured magnitude of cyclic variation in the left and right ventricular myocardium. This observation is consistent with predictions relating the overall backscatter level and the magnitude of cyclic variation. Results of this study suggest cyclic variation measurements may offer a useful approach for characterizing intrinsic differences in myocardial properties of the two ventricles in assessing fetal heart development. PMID:19131208

Holland, Mark R.; Gibson, Allyson A.; Kirschner, Carol A.; Hicks, Deborah; Ludomirsky, Achiau; Singh, Gautam K.

2009-01-01

259

Cardiac sympathetic afferent denervation attenuates cardiac remodeling and improves cardiovascular dysfunction in rats with heart failure.  

PubMed

The enhanced cardiac sympathetic afferent reflex (CSAR) contributes to the exaggerated sympathoexcitation in chronic heart failure (CHF). Increased sympathoexcitation is positively related to mortality in patients with CHF. However, the potential beneficial effects of chronic CSAR deletion on cardiac and autonomic function in CHF have not been previously explored. Here, we determined the effects of chronic CSAR deletion on cardiac remodeling and autonomic dysfunction in CHF. To delete the transient receptor potential vanilloid 1 receptor-expressing CSAR afferents selectively, epicardial application of resiniferatoxin (50 ?g/mL), an ultrapotent analog of capsaicin, was performed during myocardium infarction surgery in rats. This procedure largely abolished the enhanced CSAR, prevented the exaggerated renal and cardiac sympathetic nerve activity and improved baroreflex sensitivity in CHF rats. Most importantly, we found that epicardial application of resiniferatoxin largely prevented the elevated left ventricle end-diastolic pressure, lung edema, and cardiac hypertrophy, partially reduced left ventricular dimensions in the failing heart, and increased cardiac contractile reserve in response to ?-adrenergic receptor stimulation with isoproterenol in CHF rats. Molecular evidence showed that resiniferatoxin attenuated cardiac fibrosis and apoptosis and reduced expression of fibrotic markers and transforming growth factor-? receptor I in CHF rats. Pressure-volume loop analysis showed that resiniferatoxin reduced the end-diastolic pressure volume relationships in CHF rats, indicating improved cardiac compliance. In summary, cardiac sympathetic afferent deletion exhibits protective effects against deleterious cardiac remodeling and autonomic dysfunction in CHF. These data suggest a potential new paradigm and therapeutic potential in the management of CHF. PMID:24980663

Wang, Han-Jun; Wang, Wei; Cornish, Kurtis G; Rozanski, George J; Zucker, Irving H

2014-10-01

260

Acute Hemodynamic Efficacy of a 32-ml Subcutaneous Counterpulsation Device in a Calf Model of Diminished Cardiac Function  

PubMed Central

The acute hemodynamic efficacy of an implantable counter-pulsation device (CPD) was evaluated. The CPD is a valveless single port, 32-ml stroke volume blood chamber designed to be connected to the human axillary artery using a simple surface surgical procedure. Blood is drawn into the pump during systole and ejected during diastole. The acute hemodynamic effects of the 32-ml CPD were compared to a standard clinical 40-ml intra-aortic balloon pump (IABP) in calves (80 kg, n = 10). The calves were treated by a single oral dose of Monensin to produce a model of diminished cardiac function (DCF). The CPD and IABP produced similar increases in cardiac output (6% CPD vs. 5% IABP, p > 0.5) and reduction in left ventricular external work (14% CPD vs. 13% IABP, p > 0.5) compared to DCF (p < 0.05). However, the ratio of diastolic coronary artery flow to left ventricular external work increase from DCF baseline (p < 0.05) was greater with the CPD compared to the IABP (15% vs. 4%, p < 0.05). The CPD also produced a greater reduction in left ventricular myocardial oxygen consumption from DCF baseline (p < 0.05) compared to the IABP (13% vs. 9%, p < 0.05) despite each device providing similar improvements in cardiac output. There was no early indication of hemolysis, thrombus formation, or vascular injury. The CPD provides hemodynamic efficacy equivalent to an IABP and may become a therapeutic option for patients who may benefit from prolonged counterpulsation. PMID:19033769

Koenig, Steven C.; Litwak, Kenneth N.; Giridharan, Guruprasad A.; Pantalos, George M.; Dowling, Robert D.; Prabhu, Sumanth D.; Slaughter, Mark S.; Sobieski, Michael A.; Spence, Paul A.

2010-01-01

261

Variability in the cardiac venous system of wistar rats.  

PubMed

Rats are often used as animal models in experimental cardiology for studying myocardial infarctions and various cardiologic procedures. Currently the cardiac venous system is a target for the delivery of drugs, gene vectors, angiogenetic growth factors, stem cells, and cardioprotective reagents. The purpose of this study was to describe the anatomic configuration and variability of the cardiac venous system in Wistar rats, by using the corrosion cast method and perfusion of colored latex. The distribution of veins in the rat heart disagrees with prior descriptions for other mammals, except mice, which have a similar pattern. Coronary venous drainage in the 36 rats examined consistently involved the left cardiac, left conal, major caudal, right cardiac, and right conal veins. Other veins involved inconsistently included the cranial cardiac vein (58.3% of cases), minor caudal veins (16.7%), conoanastomotic vein (66.7%), and left atrial vein (75%). In 4 cases (11.1%), the collateral veins were located between the left conal and left cardiac veins. In this study, high morphologic variability between cases was manifested by differences in the arrangement, size, mode of opening, and formation of the common root and affected all regions of the heart but primarily the right ventricle. PMID:25651085

Krešáková, Lenka; Purzyc, Halina; Schusterová, Ingrid; Fulton, Benjamin; Maloveská, Marcela; Vdoviaková, Katarina; Kravcová, Zuzanna; BoldiŽár, Martin

2015-01-01

262

Cardiac Arrhythmia Detection By ECG Feature Extraction  

NASA Astrophysics Data System (ADS)

Electrocardiogram (ECG) is a noninvasive technique used as a primary diagnostic tool for detecting cardiovascular diseases. One of the important cardiovascular diseases is cardiac arrhythmia. Computer-assisted cardiac arrhythmia detection and classification can play a significant role in the management of cardiac disorders. This paper presents an algorithm developed using Python 2.6 simulation tool for the detection of cardiac arrhythmias e.g. premature ventricular contracture (PVC), right bundle branch block (R or RBBB) and left bundle branch block (L or LBBB) by extracting various features and vital intervals (i.e. RR, QRS, etc) from the ECG waveform. The proposed method was tested over the MIT-BIH Arrhythmias Database.

Mane, Rameshwari S.; Cheeran, A. N.; Awandekar, Vaibhav D.; Rani, Priya

2013-03-01

263

Cardiac involvement in primary myopathies.  

PubMed

Simultaneous or temporarily staggered affection of both the skeletal as well as the cardiac muscle (cardiac involvement, CI) is a frequent finding in primary myopathies (MPs). CI leads to impulse generation defects, impulse conduction defects, thickened myocardium, left ventriculalr hypertrabeculation, dilatation of the cardiac cavities, secondary valve insufficiency, reduction of coronary vasodilative reserve, intracardial thrombus formation, and heart failure with systolic and diastolic dysfunction. CI has been found in Duchenne muscular dystrophy (MD), Becker MD, Emery-Dreifuss MD, facioscapulohumeral MD, sarcoglycanopathies, myotubular congenital MD, myotonic dystrophies type 1 and 2, proximal myotonic myopathy, myoadenylate deaminase deficiency, glycogenosis type II, III, IV, VII and IX, carnitine deficiency, mitochondriopathy, desmin MP, nemaline MP, central core disease, multicore MP, congenital fiber-type disproportion MP, Barth syndrome, McLeod syndrome and Bethlem MP. Patients with any of the above-mentioned myopathies should be cardiologically investigated as soon as their diagnosis is established, since sufficient cardiac therapy improves CI in MPs and since management of these patients is influenced by the degree of CI. PMID:11111138

Finsterer, J; Stöllberger, C

2000-01-01

264

Bubble stream reveals functionality of the right-to-left shunt: detection of a potential source for air embolism.  

PubMed

The existence of a right-to-left shunt may increase the likelihood of micro-embolism by allowing a flux of bubbles under hyperbaric conditions. The aim of the study was to measure the relationship between these shunts and bubbles in 10 consecutive subjects using trans-thoracic and trans-esophageal echocardiography. In video frames, all cardiac chambers were segmented and bubbles were analyzed by our proposed method and two other methods. The relationship with bubbles and shunts was divided into three classes: no bubbles, 1-20 bubbles, >20 bubbles and measured over 2160 frames. Our sensitivity was 100% and our specificity was between 90.1% and 96.4%. There were 4.32-23.78 bubbles/frame in the left atrium according to our method. After the automatic analysis, shunts were graded double-blinded by two cardiologists. Consequently, we noted that aperture size does not necessarily reflect how active the right-to-left shunt is. Instead, our proposed decay curves constitute a better tool for determining functionality. PMID:24262055

Parlak, Ismail Burak; Egi, Salih Murat; Ademoglu, Ahmet; Germonpré, Peter; Esen, Ozlem Batukan; Marroni, Alessandro; Balestra, Costantino

2014-02-01

265

The role of 1.5T cardiac MRI in the diagnosis, prognosis and management of pulmonary arterial hypertension.  

PubMed

Cardiovascular magnetic imaging is a noninvasive, three dimensional tomographic technique that allows for a detailed morphology of the cardiac chambers, the accurate quantification of right ventricle volumes, myocardial mass, and transvalvular flow. It can also determine whether right ventricular diastolic function is impaired through pulmonary hypertension. The aim of this article is to review the main kinetic, morphological and functional changes of the right ventricle that can occur in patients affected by pulmonary arterial hypertension (PAH) and to assess how the MRI findings can influence the prognosis, and guide the decision-making strategy. In those cases in which MRI shows a significant cardiac diastolic dysfunction, the prognosis is predictive of pharmacological treatment failure, and mortality. This leaves double lung-heart transplantation as the only therapeutic option. The coexistence of PAH and left ventricle impairment causes worse right ventricle function, leads to a poor prognosis, and may change the therapeutic strategies (for example, PAH associated with left ventricle dysfunction may require a double lung-heart transplant). PMID:20336377

Marrone, Gianluca; Mamone, Giuseppe; Luca, Angelo; Vitulo, Patrizio; Bertani, Alessandro; Pilato, Michele; Gridelli, Bruno

2010-08-01

266

Limitations of current echocardiographic nomograms for left ventricular, valvular, and arterial dimensions in children: a critical review.  

PubMed

An echocardiographic quantitative evaluation of the cardiac and vascular structures is often of critical importance for the diagnosis and management of congenital heart diseases. The authors reviewed the accuracy and limits of published echocardiographic nomograms for cardiac chamber, valve, and main vessel dimensions in children, with special attention to the neonatal age group. A computerized literature search in the National Library of Medicine using the keywords "echocardiographic normal/references values ± children/neonates/newborns" was performed. The research was redefined adding separately the keywords "aortic valve/annulus," "aortic arch," "atrio-ventricular valve/annulus," "left ventricle," "mitral valve/annulus," "pulmonary valve/annulus," "pulmonary artery," and "tricuspid valve/annulus." The analysis highlights the accuracy of the latest studies but also underscores that some limitations remain. In many studies, the number of healthy subjects was limited, with poor differentiation among age subgroups, and neonates were fully investigated in a very limited number of studies; moreover, data for many cardiac structures were not numerous, especially for the aortic arch and pulmonary branches. Finally, several methodologic limitations were encountered, including the lack of standardization, the different types of body size measurements used for normalization, and the various ways to express normalized data. As a result, nomograms were heterogeneous and although for some cardiac structures provided comparable confidence intervals, for others showed widely different values. The lack of solid, standardized nomograms, based on a large set of healthy children, may affect accuracy in estimating the severity of defects, especially in neonates, and possibly introduce bias in the clinical decision-making process. PMID:22101087

Cantinotti, Massimiliano; Scalese, Marco; Molinaro, Sabrina; Murzi, Bruno; Passino, Claudio

2012-02-01

267

Rapid sampling culture chamber.  

PubMed Central

An all-glass chamber for culturing anaerobic and aerobic bacteria in liquid medium is described. The system permits both rapid sampling and turbidimetric measurements under controlled atmospheric conditions. PMID:350159

Carey, A E; Schroeder, B W

1978-01-01

268

The KLOE drift chamber  

Microsoft Academic Search

The tracking detector of the KLOE experiment is 4m diameter, 3.3m length drift chamber, designed to contain a large fraction of the decays of low-energy KL produced at the Frascati DA?NE ?-factory. The chamber is made by a thin carbon fiber structure and operated with a helium-based gas mixture in order to minimise conversion of low-energy photons and multiple scattering

M. Adinolfi; A. Aloisio; F. Ambrosino; A. Andryakov; A. Antonelli; M. Antonelli; F. Anulli; C. Bacci; A. Bankamp; G. Barbiellini; F. Bellini; G. Bencivenni; S. Bertolucci; C. Bini; C. Bloise; V. Bocci; F. Bossi; P. Branchini; S. A. Bulychjov; G. Cabibbo; A. Calcaterra; R. Caloi; P. Campana; G. Capon; G. Carboni; A. Cardini; M. Casarsa; G. Cataldi; F. Ceradini; F. Cervelli; F. Cevenini; G. Chiefari; P. Ciambrone; S. Conetti; S. Conticelli; E. De Lucia; G. De Robertis; R. De Sangro; P. De Simone; G. De Zorzi; S. Dell'Agnello; A. Denig; A. Di Domenico; C. Di Donato; S. Di Falco; A. Doria; E. Drago; V. Elia; O. Erriquez; A. Farilla; G. Felici; A. Ferrari; M. L. Ferrer; G. Finocchiaro; C. Forti; A. Franceschi; P. Franzini; M. L. Gao; C. Gatti; P. Gauzzi; S. Giovannella; V. Golovatyuk; E. Gorini; F. Grancagnolo; W. Grandegger; E. Graziani; P. Guarnaccia; U. v. Hagel; H. G. Han; S. W. Han; X. Huang; M. Incagli; L. Ingrosso; Y. Y. Jang; W. Kim; W. Kluge; V. Kulikov; F. Lacava; G. Lanfranchi; J. Lee-Franzini; F. Lomtadze; C. Luisi; C. S. Mao; M. Martemianov; M. Matsyuk; W. Mei; L. Merola; R. Messi; S. Miscetti; A. Moalem; S. Moccia; M. Moulson; S. Mueller; F. Murtas; M. Napolitano; A. Nedosekin; M. Panareo; L. Pacciani; P. Pagès; M. Palutan; L. Paoluzi; E. Pasqualucci; L. Passalacqua; M. Passaseo; A. Passeri; V. Patera; E. Petrolo; G. Petrucci; D. Picca; G. Pirozzi; C. Pistillo; M. Pollack; L. Pontecorvo; M. Primavera; F. Ruggieri; P. Santangelo; E. Santovetti; G. Saracino; R. D. Schamberger; C. Schwick; B. Sciascia; A. Sciubba; F. Scuri; I. Sfiligoi; J. Shan; P. Silano; T. Spadaro; S. Spagnolo; E. Spiriti; C. Stanescu; G. L. Tong; L. Tortora; E. Valente; P. Valente; B. Valeriani; G. Venanzoni; S. Veneziano; Y. Wu; Y. G. Xie; P. P. Zhao; Y. Zhou

2001-01-01

269

Mercury Chamber Considerations  

E-print Network

Mercury Chamber Considerations V. Graves IDS-NF Target Studies July 2011 #12;2 Managed by UT-Battelle for the U.S. Department of Energy Mercury Chamber Considerations, July 2011 Flow Loop Review · 1 cm dia nozzle, 20 m/s jet requires 1.57 liter/sec mercury flow (94.2 liter/min, 24.9 gpm). · MERIT experiment

McDonald, Kirk

270

Implantation of a left ventricular assist device in situs inversus  

Microsoft Academic Search

A 42-year-old man with situs inversus was referred to our institution because of end-stage ischemic cardiomyopathy. Cardiac arrest occurred after admission, and the patient underwent cardiopulmonary resuscitation. An extracorporeal left ventricular assist device (Berlin Heart) was implanted as a bridge to transplantation. This is one of the first reports of left ventricular assist device implantation in a patient with situs

Michele Musci; Michael J Jurmann; Thorsten Drews; Charles Yankah; Hermann Kuppe; Yuguo Weng; Roland Hetzer

2002-01-01

271

Sleeve reaction chamber system  

DOEpatents

A chemical reaction chamber system that combines devices such as doped polysilicon for heating, bulk silicon for convective cooling, and thermoelectric (TE) coolers to augment the heating and cooling rates of the reaction chamber or chambers. In addition the system includes non-silicon-based reaction chambers such as any high thermal conductivity material used in combination with a thermoelectric cooling mechanism (i.e., Peltier device). The heat contained in the thermally conductive part of the system can be used/reused to heat the device, thereby conserving energy and expediting the heating/cooling rates. The system combines a micromachined silicon reaction chamber, for example, with an additional module/device for augmented heating/cooling using the Peltier effect. This additional module is particularly useful in extreme environments (very hot or extremely cold) where augmented heating/cooling would be useful to speed up the thermal cycling rates. The chemical reaction chamber system has various applications for synthesis or processing of organic, inorganic, or biochemical reactions, including the polymerase chain reaction (PCR) and/or other DNA reactions, such as the ligase chain reaction.

Northrup, M. Allen (Berkeley, CA); Beeman, Barton V. (San Mateo, CA); Benett, William J. (Livermore, CA); Hadley, Dean R. (Manteca, CA); Landre, Phoebe (Livermore, CA); Lehew, Stacy L. (Livermore, CA); Krulevitch, Peter A. (Pleasanton, CA)

2009-08-25

272

Echocardiographic assessment of cardiac disease  

NASA Technical Reports Server (NTRS)

The physical principles and current applications of echocardiography in assessment of heart diseases are reviewed. Technical considerations and unresolved points relative to the use of echocardiography in various disease states are stressed. The discussion covers normal mitral valve motion, mitral stenosis, aortic regurgitation, atrial masses, mitral valve prolapse, and idiopathic hypertrophic subaortic stenosis. Other topics concern tricuspic valve abnormalities, aortic valve disease, pulmonic valve, pericardial effusion, intraventricular septal motion, and left ventricular function. The application of echocardiography to congenital heart disease diagnosis is discussed along with promising ultrasonic imaging systems. The utility of echocardiography in quantitative evaluation of cardiac disease is demonstrated.

Popp, R. L.

1976-01-01

273

Non-invasive quick diagnosis of cardiovascular problems from visible and invisible abnormal changes with increased cardiac troponin I appearing on cardiovascular representation areas of the eyebrows, left upper lip, etc. of the face & hands: beneficial manual stimulation of hands for acute anginal chest pain, and important factors in safe, effective treatment.  

PubMed

Our previous study indicated that there are at least 7 cardiovascular representation areas on the face, including the "Eyebrows", both sides of the "Nose", "Lelt Upper Lip" and the "Outside of the corner of both sides of the mouth," in addition to 2 areas in each hand. When there are cardiovascular problems, some of the heart representation areas of these areas often show the following changes: 1) Most distinctive visible changes such as the initial whitening with or without long white hair, then hair loss and complete disappearance of the hairs of the heart representation area of "Eyebrows" 2) Invisible biochemical changes that happen in heart representation areas at the "Left Upper Lips", 3) "Nose" below eye level as well as 4) "3rd segment of Middle Finger of Hands." Most distinctive visible & invisible changes are found in heart representation areas on the "Eyebrow", located nearest to the midline of face, where the color of the hairs becomes white compared with the rest of the Eyebrow. Then the cardiovascular problem advances, and hair starts disappearing. When there are no hairs at the heart representation areas of the Eyebrow, usually Cardiac Troponin I is increased to a very serious, abnormal high value. Most of the cardiovascular representation areas of the face show, regardless of presence or absence of visible change. When there is a cardiovascular problem, not only simple Bi-Digital O-Ring Test can detect without using any instrument in several minutes but also, corresponding biochemical changes of abnormally increased Cardiac Troponin I level can often be detected non-invasively from these Organ Representation Areas of Face & Hands, although changes in Eyebrows, L-Upper Lip & 3rd segment of middle fingers are clinically the most reliable changes & easy to identify the locations. Manual Stimulation of Hand's heart representation areas often eliminated acute anginal chest pain before medical help became available. Important factors for safe, effective treatment of heart disease & cancer were also presented. Significant beneficial effect of optimal dose of Vitamin D3 400 I.U. for average adult on heart, brain and cancer, and harmful effect of widely used 2000 I.U., was emphasized. PMID:25219029

Omura, Yoshiaki; Jones, Marilyn K; Duvvi, Harsha; Shimotsuura, Yasuhiro; Ohki, Motomu; Rodriques, Aaron

2014-01-01

274

Left Atrial High-Grade Undifferentiated Pleomorphic Sarcoma Protruding Through the Mitral Valve.  

PubMed

Primary cardiac tumors are uncommon. Malignant neoplasms account for 25%, including 75% of cardiac sarcomas. A 53-year-old female complained of exertional dyspnea and orthopnea. Chest computed tomography revealed a mass within the left atrium. Echocardiography confirmed a bilobed left atrial mass protruding through the mitral valve orifice. The tumor was completely resected and was histologically diagnosed as a high-grade pleomorphic sarcoma. A 13-month follow-up was achieved without any recurrence on magnetic resonance imaging. PMID:25468101

Bégué, Celine; Barreda, Eleodoro; Hammoudi, Nadjib; Fouret, Pierre; Toledano, Dan; Isnard, Richard; Leprince, Pascal; Montalescot, Gilles; Barthélémy, Olivier

2014-12-01

275

Incidence, Diagnosis and Prognosis of Cardiac Amyloidosis  

PubMed Central

Background and Objectives Cardiac involvement is frequent in systemic amyloidosis and is the most important determinant of the clinical outcome. The aims of this study were to assess the incidence and prognosis of cardiac amyloidosis and discuss the diagnostic issues related to cardiac amyloidosis. Subjects and Methods We retrospectively studied all patients diagnosed with systemic amyloidosis who presented to our institution from January 1999 to December 2011. Results Of the 129 patients with systemic amyloidosis, cardiac amyloidosis was diagnosed in 62 patients. At the 3 years' follow-up of the patients with systemic amyloidosis, there was a statistically significant difference in mortality between patients with cardiac amyloidosis and the rest of the patients (58.1% vs. 37.3%, p=0.008). In the Cox proportional hazard model, old age {hazard ratio (HR) 18.336, p=0.006}, elevation of cardiac troponin I (cTNI) (HR 13.246, p=0.020), left ventricular (LV) systolic dysfunction (HR 5.137, p=0.041) and diastolic dysfunction (HR 64.595, p=0.022) were independently associated with survival in cardiac amyloidosis. In the diagnosis of monoclonal gammopathy, serum or urine protein electrophoresis was not sensitive enough to be used clinically compared to serum free light chain assay (35.8% vs. 96.4%). Conclusion In systemic amyloidosis, cardiac involvement was the most important determinant of the prognosis, and old age, elevation of cTNI, LV systolic dysfunction and diastolic dysfunction were independently associated with survival in cardiac amyloidosis. PMID:24363751

Lee, Min-Ho; Lee, Seung-Pyo; Kim, Yong-Jin

2013-01-01

276

Electrical stimulation systems for cardiac tissue engineering  

PubMed Central

We describe a protocol for tissue engineering of synchronously contractile cardiac constructs by culturing cardiac cells with the application of pulsatile electrical fields designed to mimic those present in the native heart. Tissue culture is conducted in a customized chamber built to allow for cultivation of (i) engineered three-dimensional (3D) cardiac tissue constructs, (ii) cell monolayers on flat substrates or (iii) cells on patterned substrates. This also allows for analysis of the individual and interactive effects of pulsatile electrical field stimulation and substrate topography on cell differentiation and assembly. The protocol is designed to allow for delivery of predictable electrical field stimuli to cells, monitoring environmental parameters, and assessment of cell and tissue responses. The duration of the protocol is 5 d for two-dimensional cultures and 10 d for 3D cultures. PMID:19180087

Tandon, Nina; Cannizzaro, Christopher; Chao, Pen-Hsiu Grace; Maidhof, Robert; Marsano, Anna; Au, Hoi Ting Heidi; Radisic, Milica; Vunjak-Novakovic, Gordana

2009-01-01

277

Electrical stimulation systems for cardiac tissue engineering.  

PubMed

We describe a protocol for tissue engineering of synchronously contractile cardiac constructs by culturing cardiac cells with the application of pulsatile electrical fields designed to mimic those present in the native heart. Tissue culture is conducted in a customized chamber built to allow for cultivation of (i) engineered three-dimensional (3D) cardiac tissue constructs, (ii) cell monolayers on flat substrates or (iii) cells on patterned substrates. This also allows for analysis of the individual and interactive effects of pulsatile electrical field stimulation and substrate topography on cell differentiation and assembly. The protocol is designed to allow for delivery of predictable electrical field stimuli to cells, monitoring environmental parameters, and assessment of cell and tissue responses. The duration of the protocol is 5 d for two-dimensional cultures and 10 d for 3D cultures. PMID:19180087

Tandon, Nina; Cannizzaro, Christopher; Chao, Pen-Hsiu Grace; Maidhof, Robert; Marsano, Anna; Au, Hoi Ting Heidi; Radisic, Milica; Vunjak-Novakovic, Gordana

2009-01-01

278

Paradoxical carbon dioxide embolism during laparoscopic cholecystectomy as a cause of cardiac arrest and neurologic sequelae: a case report  

PubMed Central

An 81-year-old male patient was scheduled for a laparoscopic cholecystectomy due to acute cholecystitis. About 50 minutes into the operation, the arterial blood pressure suddenly decreased and ventricular fibrillation appeared on the electrocardiography. The patient received cardiopulmonary resuscitation and recovered a normal vital sign. We suspected a carbon dioxide embolism as the middle hepatic vein had been injured during the surgery. We performed a transesophageal echocardiography and were able to confirm the presence of multiple gas bubbles in all of the cardiac chambers. After the operation, the patient presented a stable hemodynamic state, but showed weaknesses in the left arm and leg. There were no acute lesions except for a chronic cerebral cortical atrophy and chronic microvascular encephalopathy on the postoperative brain-computed tomography, 3D angiography and magnetic resonance image. Fortunately, three days after the operation, the patient's hemiparesis had entirely subsided and he was discharged without any neurologic sequelae.

Shin, Hye Young; Kim, Dong Wook; Kim, Ju Deok; Yu, Soo Bong; Kim, Doo Sik; Kim, Kyung Han

2014-01-01

279

Structural causes of cardiac dysfunction in uremia.  

PubMed

While coronary heart disease is undoubtedly a major cause of cardiac morbidity and mortality in uremia, important noncoronary problems contribute to the common presence of cardiac problems. Based on clinical and experimental studies, we could show: (i) Left ventricular hypertrophy (LVH) can be dissociated, at least in part, from elevation of blood pressure. (ii) In uremia, PTH-dependent intermyocardiocytic fibrosis occurs; it may account, at least in part, for disturbed LV compliance and contribute to the arrhythmogenic potential. (iii) Blood pressure-independent abnormalities of intracardiac arterioles and reduced myocardial capillary supply are observed. PMID:8516501

Rambausek, M; Amann, K; Mall, G; Ritz, E

1993-01-01

280

Phenotyping Cardiac Gene Therapy in Mice  

PubMed Central

Heart disease is the leading health problem of industrialized countries. The development of gene therapies tailored towards the heart has grown exponentially over the past decade. Murine models of heart diseases have played a pivotal role in testing novel cardiac gene therapy approaches. Unfortunately, the small body size and rapid heart rate of mice present a great challenge to heart function evaluation. Here we outline the commonly used cardiac phenotyping methods of treadmill exercise regimen, full 12-lead electrocardiographic assay and left ventricular catheterization hemodynamic assay. Application of these protocols will allow critical testing of gene therapy efficacy in mouse models of heart diseases. PMID:21194023

Bostick, Brian; Yue, Yongping; Duan, Dongsheng

2011-01-01

281

Conduction of the Cardiac Impulse  

PubMed Central

The excitability of short segments (5–7 mm) of bundles of canine Purkinje fibers was depressed by exposure to 15–18 mM K+, to 15–18 mM K+ plus 5 x 10-6 epinephrine or norepinephrine, to low K+, and to low Na+. The depressed segment was in the center chamber of a three-chamber bath; the ends of the bundle were exposed to normal Tyrode solution. Each method of depression resulted in slow and probably decremental conduction with an effective conduction velocity in the middle chamber of about 0.05 m/sec, or one-way block, or two-way block with summation of the graded responses in the depressed region. The action potential in the depressed segment (the slow response) differs from the normal action potential in its response to applied stimuli. A second active depolarization can be evoked by cathodal stimulation during much of the slow response. The response in the depressed segment is graded. The response of depressed fibers may depend on excitatory events similar to those responsible for the slow component of the cardiac action potential. It is suggested that the slow response can propagate, at least decrementally, in fibers in which the rapid, Na+-dependent upstroke is absent, and can cause reentrant excitation by so doing. PMID:5058476

Cranefield, Paul F.; Wit, Andrew L.; Hoffman, Brian F.

1972-01-01

282

Calcific left atrium: A rare consequence of endocarditis.  

PubMed

Usually, cardiac calcifications are observed in aortic and mitral valves, atrio-ventricular plane, mitral annulus, coronary arteries, pericaridium (usually causing constrictive pericarditis) and cardiac masses. Calcifications of atrial walls are unusual findings that can be identified only using imaging with high spatial resolution, such as cardiac magnetic resonance and computed tomography. We report a case of a 43-year-old patient with no history of heart disease that underwent cardiac evaluation for mild dyspnoea. The echocardiogram showed a calcific aortic valve and a hyper-echogenic lesion located in atrio-ventricular plane. The patient was submitted to cardiac magnetic resonance and to computed tomography imaging to better characterize the localization of mass. The clinical features and location of calcified lesion suggest an infective aetiology causing an endocarditis involving the aortic valve, atrio-ventricular plane and left atrium. Although we haven't data to support a definite and clear diagnosis, the clinical features and location of the calcified lesion suggest an infective aetiology causing an endocarditis involving the aortic valve, atrio-ventricular plane and left atrium. The patient was followed for 12 mo both clinically and by electrocardiogram and echocardiography without worsening of clinical, electrocardiographic and echocardiographic data. Cardiac magnetic resonance imaging and computed tomography are ideal methods for identifying and following over time patients with calcific degeneration in the heart. PMID:25276304

Dattilo, Giuseppe; Anfuso, Carmelo; Casale, Matteo; Giugno, Vincenza; Camarda, Lorenzo; Laganà, Natascia; Di Bella, Gianluca

2014-09-26

283

Prenatal Diagnosis of the Fetus with Hypoplastic Left Heart Syndrome  

Microsoft Academic Search

Objectives: To review our 13-year experience with prenatally detected hypoplastic left heart syndrome (HLHS) of which management remains controversial. Material and Methods: Retrospective study of the management and outcome in all cases of HLHS diagnosed prenatally in a tertiary referral center for pediatric cardiology and cardiac surgery between January 1988 and July 2001. Results: The diagnosis of HLHS was made

Paul M. Verheijen; Lukas A. Lisowski; Rutger F. Plantinga; J. François Hitchcock; Ger B. W. E. Bennink; Philip Stoutenbeek; Erik J. Meijboom

2003-01-01

284

Embedding Overlap Priors in Variational Left Ventricle Tracking  

Microsoft Academic Search

We propose to embed overlap priors in variational tracking of the left ventricle (LV) in cardiac magnetic resonance (MR) sequences. The method consists of evolving two curves toward the LV endo- and epicardium boundaries. We derive the curve evolution equations by minimizing two functionals each containing an original overlap prior constraint. The latter measures the conformity of the overlap between

Ismail Ben Ayed; Shuo Li; Ian Ross

2009-01-01

285

Congenital left atrial appendage aneurysm associated with a systemic embolism.  

PubMed

A 20 year-old woman presented with systemic embolisation. On subsequent investigation, she was diagnosed with a congenital left atrial appendage aneurysm. Few case reports are reported in the literature. This cardiac malformation presents a diagnostic challenge in patients with cardiomegaly. PMID:24854482

Tidake, Abhay; Gangurde, Pranil; Mahajan, Ajay

2015-03-01

286

Left ventricular function in double inlet left ventricle before the Fontan operation: comparison with tricuspid atresia.  

PubMed Central

Fourteen patients with double inlet left ventricle and nine patients with tricuspid atresia had biplane left ventricular angiography with simultaneous measurement of left ventricular pressure by micromanometer. Age distribution, haemodynamic function, and previous palliative operation were similar in the two groups. Left ventricular volumes were calculated frame by frame throughout the cardiac cycle by Simpson's rule. The end diastolic volume index was similar in the two groups, but the ejection fraction was significantly lower in tricuspid atresia. Left ventricular peak filling and emptying rates were also lower in tricuspid atresia, although heart rates in the two groups were similar. End diastolic shape index was significantly higher in patients with tricuspid atresia, indicating a more globular shape, and changed less during systole, suggesting differences in the mechanism of ejection between the two groups. Analysis of pressure-volume loops showed normal phase relations between pressure and volume, but systolic stroke work was reduced in tricuspid atresia and correlated with stroke volume and shape change. Left ventricular function was impaired in patients with tricuspid atresia when compared with those with double inlet left ventricle and this finding may reflect structural differences caused by the absence of one atrioventricular connection. Images Fig 1 PMID:3190961

Redington, A N; Knight, B; Oldershaw, P J; Shinebourne, E A; Rigby, M L

1988-01-01

287

Automated Electrostatics Environmental Chamber  

NASA Technical Reports Server (NTRS)

The Mars Electrostatics Chamber (MEC) is an environmental chamber designed primarily to create atmospheric conditions like those at the surface of Mars to support experiments on electrostatic effects in the Martian environment. The chamber is equipped with a vacuum system, a cryogenic cooling system, an atmospheric-gas replenishing and analysis system, and a computerized control system that can be programmed by the user and that provides both automation and options for manual control. The control system can be set to maintain steady Mars-like conditions or to impose temperature and pressure variations of a Mars diurnal cycle at any given season and latitude. In addition, the MEC can be used in other areas of research because it can create steady or varying atmospheric conditions anywhere within the wide temperature, pressure, and composition ranges between the extremes of Mars-like and Earth-like conditions.

Calle, Carlos; Lewis, Dean C.; Buchanan, Randy K.; Buchanan, Aubri

2005-01-01

288

Cardiac-specific Traf2 overexpression enhances cardiac hypertrophy through activating AKT/GSK3? signaling.  

PubMed

Tumor necrosis factor superfamily ligands provoke a dilated cardiac phenotype signal through a common scaffolding protein termed tumor necrosis factor receptor-associated factor 2 (Traf2); however, Traf2 signaling in the adult mammalian cardiac hypertrophy is not fully understood. This study was aimed to identify the effect of Traf2 on cardiac hypertrophy and the underlying mechanisms. A significant up-regulation of Traf2 expression was observed in mice failing hearts. To further investigate the role of Traf2 in cardiac hypertrophy, we used cultured neonatal rat cardiomyocytes with gain and loss of Traf2 function and cardiac-specific Traf2-overexpressing transgenic (TG) mice. In cultured cardiomyocytes, Traf2 positively regulated angiotensin II (Ang II)-mediated hypertrophic growth, as detected by [(3)H]-Leucine incorporation, cardiac myocyte area, and hypertrophic marker protein levels. Cardiac hypertrophy in vivo was produced by constriction of transverse aortic (TAC) in TG mice and their wild-type controls. The extent of cardiac hypertrophy was evaluated by echocardiography as well as by pathological and molecular analyses of heart samples. Traf2 overexpression in the heart remarkably enhanced cardiac hypertrophy, left ventricular dysfunction in mice in response to TAC. Further analysis of the signaling pathway in vitro and in vivo suggested that these adverse effects of Traf2 were associated with the activation of AKT/glycogen synthase kinase 3? (GSK3?). The present study demonstrates that Traf2 serves as a novel mediator that enhanced cardiac hypertrophy by activating AKT/GSK3? signaling. PMID:24378234

Huang, Yinqing; Wu, Dengyin; Zhang, Xin; Jiang, Minghua; Hu, Chaohui; Lin, Jiangfeng; Tang, Jifei; Wu, Lianpin

2014-02-25

289

Transseptal fine needle aspiration of a large left atrial tumour.  

PubMed

The diagnosis of cardiac tumours is often based on images without tissue diagnosis or tissue obtained at surgery. Percutaneous myocardial biopsy via a transvenous approach has been described in literatures but this technique is not feasible with left atrial tumours. We report a patient presenting with heart failure and left atrial tumour. The diagnosis of spindle cell neoplasm was established pre-operatively via successful transseptal fine needle aspiration of cells from a left atrial tumour. We believe this technique worth consideration to aid pre-surgery diagnosis. PMID:19656723

Wong, Chi Wing; Ruygrok, Peter; Sutton, Timothy; Ding, Patricia; van Vliet, Chris; Occleshaw, Christopher; Smith, Warren

2010-07-01

290

Apparent distance of sounds recorded in echoic and anechoic chambers  

Microsoft Academic Search

With miniature microphones inserted into the external ear canals of a model and the sound source 90° to left of midline, low-pass, and high-pass, broadband noise bursts were picked up and recorded on magnetic tape. The bursts were generated in 2 highly contrasting acoustic environments: an anechoic and an echoic chamber. The taped sounds were played back monaurally and binaurally

Robert A. Butler; Elena T. Levy; William D. Neff

1980-01-01

291

Quantitative coronary and left ventricular cineangiography  

SciTech Connect

The first section, with 12 chapters, deals with the detailed methods of computer analysis of images obtained from coronary vessels and the left ventricle. Basic principles of x-ray image formation are described, followed by details of the computer-based Cardiovascular Angiography Analysis system (CAAs) and the left-ventricular angioprocessing system (Contouromat), with their degree of validity. Other chapters discuss contour analysis, edge detection, densitometry, digital image processing, three-dimensional reconstruction, and the current status of structural analysis of the entire coronary tree. The second edition section contains 11 chapters, each exemplifying the application of these computer-based systems to almost the entire sphere of interventional cardiac imaging. Applications include intracoronary effects of nifedipine on coronary motility, left-ventricular function and myocardial oxygen consumption, various aspects of percutaneous transluminal coronary angioplasty (including left-ventricular wall stiffness), adjuvant thrombolysis, comparison of contour versus densitometric area measurements of coronary obstructions before and after percutaneous transluminal coronary angioplasty, and left-ventricular performance including lactate metabolism during vessel occlusion.

Reiber, J.H.C.; Serruys, P.W.; Slager, C.J.

1986-01-01

292

Differing effects of right ventricular pacing and left bundle branch block on left ventricular function.  

PubMed Central

OBJECTIVE--To compare the different effects of right ventricular pacing and classic left bundle branch block on left ventricular function. DESIGN--Retrospective and prospective study of 48 patients by electrocardiography, and M mode, cross sectional, and Doppler echocardiography. SETTING--A tertiary cardiac referral centre. PATIENTS--48 patients (age range 21 to 89 years, 15 women), 24 with a VVI pacemaker implanted and 24 with classic left bundle branch block. Functional mitral regurgitation was present in all those with right ventricular pacing and 22 of those with left bundle branch block. RESULTS--Age, RR interval, and left ventricular size were similar in the two groups, as were conventional measurements of overall systolic function: shortening fraction and pre-ejection and aortic ejection times. In right ventricular pacing, however, QRS duration (p < 0.01) and electromechanical delay were much longer (p < 0.001), whereas the time intervals from onset of mitral regurgitation to aortic opening (contraction time) and from A 2 to the end of mitral regurgitation (relaxation time) were consistently shorter (p < 0.01) than corresponding values in patients with left bundle branch block. Reversed splitting of the second heart sound was much commoner in left bundle branch block (p < 0.02), and only these patients showed an early systolic ventricular septal contraction. Its onset followed the initial deflection of the QRS complex by 40(15) ms and preceded mitral regurgitation by a small but consistent interval of 10 ms (p < 0.01). The onset of posterior wall thickening was synchronous with the onset of mitral regurgitation in right ventricular pacing but much later (p < 0.01) in patients with left bundle branch block. The extent of incoordinate wall motion measure as relative dimension change during pre-ejection and isovolumic relaxation period was much greater (p < 0.01) in left bundle branch block. These major differences were not altered by left ventricular cavity size in either group, nor by the presence of previous left bundle branch block in patients who were subsequently paced. CONCLUSIONS--The left ventricle seems to be activated much more rapidly with right ventricular pacing than with left bundle branch block. This applies even when left bundle branch block is present before pacing. Electromechanical delay, contraction and relaxation times, and extent of incoordinate ventricular wall motion differ strikingly between the two conditions. The use of right ventricular pacing as an experimental model of left bundle branch block in humans must be re-examined. PMID:8435243

Xiao, H B; Brecker, S J; Gibson, D G

1993-01-01

293

A vacuum chamber feedthrough  

NASA Technical Reports Server (NTRS)

Simple and inexpensive microwave feedthrough has been designed which transfers 130 ns, 5kV pulse into vacuum chamber. Feedthrough may be used over wide range and is adaptable to most coaxial cables, since either multistrand or single strand center conductor cable can be used.

Brown, V. D.

1973-01-01

294

Secondary emission gas chamber  

E-print Network

For a hadron calorimeter active element there is considered a gaseous secondary emis-sion detector (150 micron gap, 50 kV/cm). Such one-stage parallel plate chamber must be a radiation hard, fast and simple. A model of such detector has been produced, tested and some characteristics are presented.

In'shakov, V; Skvortsov, V

2014-01-01

295

Bubble Chamber Site  

NSDL National Science Digital Library

This substantial site features a large number of photos of bubble chamber (BC) tracks, many with a discussion of the physics. There is a description of how the BC works and also useful tutorial on reading BC pictures. The high quality of the images and the explanations of the events that are shown make this site especially valuable.

2006-06-19

296

Improved wire chamber  

DOEpatents

An improved gas mixture for use with proportional counter devices, such as Geiger-Mueller tubes and drift chambers. The improved gas mixture provides a stable drift velocity while eliminating wire aging caused by prior art gas mixtures. The new gas mixture is comprised of equal parts argon and ethane gas and having approximately 0.25% isopropyl alcohol vapor. 2 figs.

Atac, M.

1987-05-12

297

Left ventricular submitral aneurysms.  

E-print Network

??Retrospective institutional review of the pathology, aetiology classification and surgical management of left ventricular submitral aneurysms (LVSMA). These aneurysms are a well recognized but relatively… (more)

Du Toit, Henning

2007-01-01

298

Tissue factor deficiency causes cardiac fibrosis and left ventricular dysfunction  

Microsoft Academic Search

Exposure of blood to tissue factor (TF) activates the extrinsic (TF:FVIIa) and intrinsic (FVIIIa:FIXa) pathways of coagulation. In this study, we found that mice expressing low levels of human TF (1% of wild-type levels) in an mTF-\\/- background had significantly shorter lifespans than wild-type mice, in part, because of spontaneous fatal hemorrhages. All low-TF mice exhibited a selective heart defect

R. Pawlinski; A. Fernandes; B. Kehrle; B. Pedersen; G. Parry; J. Erlich; R. Pyo; D. Gutstein; J. Zhang; F. Castellino; E. Melis; P. Carmeliet; G. Baretton; T. Luther; M. Taubman; E. Rosen; N. Mackman

2002-01-01

299

Cardiac magnetic resonance in cocaine-induced myocardial damage.  

PubMed

A 54-year-old male with history of cocaine abuse underwent trans-thoracic echocardiography that showed hyper-echogenicity of the basal segments of the septum and infero-lateral wall of the left ventricle. The patient underwent cardiac CT that reported diffuse non-obstructive CAD. Cardiac MR showed LGE patterns consistent with non-ischemic myocardial damage associated with cocaine abuse. PMID:24481724

Arcadi, Teresa; Bolognesi, Massimo; Maffei, Erica; Cademartiri, Filippo

2014-04-01

300

Left ventricular thrombosis after blunt chest trauma.  

PubMed

A 22-year-old man was admitted to our observation with left ventricular thrombus arising after blunt chest trauma occurring during a ski accident one year before. None was obtained from a review of instrumental and laboratory data at trauma time. Transesophageal echocardiography showed an intraventricular thrombus and severe hypokinesia at the apex. Standard cardiac surgery procedure was performed and postoperative period was uneventful. Echocardiography controls at 6/12 months showed a normal apex kinesia. This case shows the importance of hospitalization, hemodynamics monitorization and late serial echocardiographic controls for timely diagnosis and management of myocardial contusion and consecutive ventricular thrombus formation to prevent life-threatening complications. PMID:11292936

Ruvolo, G; Fattouch, K; Speziale, G; Macrina, F; Tonelli, E; Marino, B

2001-04-01

301

TWO-CORONARY REPAIR FOR ANOMALOUS LEFT CORONARY ARTERY FROM PULMONARY ARTERY  

Microsoft Academic Search

Between January 1989 and December 1998, 13 patients (7 males) aged 3 months to 32 years, underwent surgery for anomalous left coronary artery from the pulmonary artery. Eight presented with congestive cardiac failure and all had evidence of left ventricular dysfunction. One patient had associated tetralogy of Fallot. Preoperative diagnosis was established by echocardiography and cineangiography. Nine patients underwent Takeuchi

Sachin Talwar; Anil Bhan; Rajesh Sharma; Shiv Kumar Choudhary; Balram Airan; Anita Saxena; Shyam Sunder Kothari; Rajnish Juneja

302

Sustained Ventricular Tachycardia In An Apparently Healthy Heart: A Very Localized Left Dominant Arrhythmogenic Cardiomyopathy  

PubMed Central

A 62-year-old man admitted for presyncope presented two symptomatic sustained ventricular tachycardia with right bundle branch morphology and inferior axis suggesting a pathology of the left ventricular lateral wall, the site where Cardiac Magnetic Resonance demonstrated a thinned, hypokinetic segment with fibro-fatty subepicardial infiltration. A very localized Left Dominant Arrhythmogenic Cardiomyopathy was diagnosed and an ICD implanted. PMID:25609898

Cresti, Alberto; De Sensi, Francesco; Severi, Silva; Miracapillo, Gennaro

2014-01-01

303

Sustained ventricular tachycardia in an apparently healthy heart: a very localized left dominant arrhythmogenic cardiomyopathy.  

PubMed

A 62-year-old man admitted for presyncope presented two symptomatic sustained ventricular tachycardia with right bundle branch morphology and inferior axis suggesting a pathology of the left ventricular lateral wall, the site where Cardiac Magnetic Resonance demonstrated a thinned, hypokinetic segment with fibro-fatty subepicardial infiltration. A very localized Left Dominant Arrhythmogenic Cardiomyopathy was diagnosed and an ICD implanted. PMID:25609898

Cresti, Alberto; De Sensi, Francesco; Severi, Silva; Miracapillo, Gennaro

2014-01-01

304

Combustor with fuel preparation chambers  

NASA Technical Reports Server (NTRS)

An annular combustor having fuel preparation chambers mounted in the dome of the combustor. The fuel preparation chamber comprises an annular wall extending axially from an inlet to an exit that defines a mixing chamber. Mounted to the inlet are an air swirler and a fuel atomizer. The air swirler provides swirled air to the mixing chamber while the atomizer provides a fuel spray. On the downstream side of the exit, the fuel preparation chamber has an inwardly extending conical wall that compresses the swirling mixture of fuel and air exiting the mixing chamber.

Zelina, Joseph (Inventor); Myers, Geoffrey D. (Inventor); Srinivasan, Ram (Inventor); Reynolds, Robert S. (Inventor)

2001-01-01

305

Multi-chamber deposition system  

DOEpatents

A system for the simultaneous deposition of different coatings onto a thin web within a large volume vacuum chamber is disclosed which chamber is provided with a plurality of deposition chambers in which the different layers are deposited onto the film as its moves from a supply roll to a finished take-up roll of coated web. The deposition chambers provided within the large vacuum chamber are provided with separate seals which minimize back diffusion of any dopant gas from adjacent deposition chambers.

Jacobson, Richard L. (Roseville, MN); Jeffrey, Frank R. (Shoreview, MN); Westerberg, Roger K. (Cottage Grove, MN)

1989-10-17

306

Multi-chamber deposition system  

DOEpatents

A system for the simultaneous deposition of different coatings onto a thin web within a large volume vacuum chamber is disclosed which chamber is provided with a plurality of deposition chambers in which the different layers are deposited onto the film as its moves from a supply roll to a finished take-up roll of coated web. The deposition chambers provided within the large vacuum chamber are provided with separate seals which minimize back diffusion of any dopant gas from adjacent deposition chambers.

Jacobson, Richard L. (Roseville, MN); Jeffrey, Frank R. (Shoreview, MN); Westerberg, Roger K. (Cottage Grove, MN)

1989-06-27

307

Effect of Depression and Sertraline Treatment on Cardiac Function in Female Nonhuman Primates  

PubMed Central

Objective Depression is a proposed risk factor for heart failure based largely on epidemiological data; little experimental data is available addressing this hypothesis. Methods Depression was evaluated in relation to cardiac structural and functional phenotypes assessed by transthoracic echocardiography in 42 adult female cynomolgus monkeys that consumed a Western-like diet for 3 years. Half of the monkeys were treated with the SSRI sertraline HCl for 18 months and depressive behavior was assessed for 12 months prior to echocardiography. Results Depressed monkeys (the 19/42 with depressive behavior rates above the mean rate) had higher HRs (171±4.1 vs 152±6.1), and smaller BSA (0.13±0.003 vs 0.15±0.004). Cardiac measures showed lower LV end systolic dimension (0.75±0.05 vs 0.89±0.04), LV systolic (0.76±0.08 vs 1.2±0.11) and diastolic (2.4±0.23 vs 3.4±0.26) volumes, and left atrial volumes (1.15±0.14 vs 1.75±0.12) in depressed versus nondepressed monkeys (p’s <0.05). Doppler profiles of depressed monkeys indicated greater myocardial relaxation (higher e? and higher e?/a? ratio) and lower filling pressures (lower E/e?) compared to nondepressed monkeys (p’s<0.05). Although treatment with sertraline reduced HR (150±5.8 vs 171±4.8) and modestly increased chamber dimensions (left ventricular end systolic dimension: 0.91±0.05 vs 0.74±0.03; left ventricular end diastolic dimension, BSA adjusted 1.69±0.05 vs 1.47±0.06) (p’s<0.05), it did not overtly affect systolic or diastolic function (p’s >0.10). Conclusions These data suggest that behavioral depression in female primates is accompanied by differences in cardiac function, although not in ways classically associated with subclinical heart failure. SSRIs show promise in supporting heart function by reducing HR and perhaps improving LV filling, however further investigation is needed to confirm this hypothesis. PMID:24470133

Groban, Leanne; Kitzman, Dalane W.; Register, Thomas C.; Shively, Carol A.

2014-01-01

308

Transcriptional profiling of the heart reveals chamber-specific gene expression patterns.  

PubMed

Cardiac chamber-specific gene expression is critical for the normal development and function of the heart. To investigate the genetic basis of cardiac anatomical specialization, we have undertaken a nearly genome-wide transcriptional profiling of the four heart chambers and the interventricular septum. Rigorous statistical analysis has allowed the identification of known and novel members of gene families that are felt to be important in cardiac development and function, including LIM proteins, homeobox proteins, wnt and T-box pathway proteins, as well as structural proteins like actins and myosins. In addition, these studies have allowed the identification of thousands of additional differentially expressed genes, for which there is little structural or functional information. Clustering of genes with known and unknown functions provides insights into signaling pathways that are essential for development and maintenance of chamber-specific features. To facilitate future research in this area, a searchable internet database has been constructed that allows study of the chamber-specific expression of any gene represented on this comprehensive microarray. It is anticipated that further study of genes identified through this effort will provide insights into the specialization of heart chamber tissues, and their specific roles in cardiac development, aging, and disease. PMID:14576202

Tabibiazar, Raymond; Wagner, Roger A; Liao, Arnold; Quertermous, Thomas

2003-12-12

309

Left Business Observer  

NSDL National Science Digital Library

Edited by Wall Street author Doug Henwood, the Left Business Observer site features selected articles from the print journal by the same name (1992-present). The site provides special reports on current political issues, in addition to a discussion forum and US labor statistics with commentary from a "left" perspective.

310

Three chamber negative ion source  

DOEpatents

A negative ion vessel is divided into an excitation chamber, a negative ionization chamber and an extraction chamber by two magnetic filters. Input means introduces neutral molecules into a first chamber where a first electron discharge means vibrationally excites the molecules which migrate to a second chamber. In the second chamber a second electron discharge means ionizes the molecules, producing negative ions which are extracted into or by a third chamber. A first magnetic filter prevents high energy electrons from entering the negative ionization chamber from the excitation chamber. A second magnetic filter prevents high energy electrons from entering the extraction chamber from the negative ionizing chamber. An extraction grid at the end of the negative ion vessel attracts negative ions into the third chamber and accelerates them. Another grid, located adjacent to the extraction grid, carries a small positive voltage in order to inhibit positive ions from migrating into the extraction chamber and contour the plasma potential. Additional electrons can be suppressed from the output flux using ExB forces provided by magnetic field means and the extractor grid electric potential.

Leung, Ka-Ngo (Hercules, CA); Ehlers, Kenneth W. (Alamo, CA); Hiskes, John R. (Livermore, CA)

1985-01-01

311

Left Atrial Anatomy Relevant to Catheter Ablation  

PubMed Central

The rapid development of interventional procedures for the treatment of arrhythmias in humans, especially the use of catheter ablation techniques, has renewed interest in cardiac anatomy. Although the substrates of atrial fibrillation (AF), its initiation and maintenance, remain to be fully elucidated, catheter ablation in the left atrium (LA) has become a common therapeutic option for patients with this arrhythmia. Using ablation catheters, various isolation lines and focal targets are created, the majority of which are based on gross anatomical, electroanatomical, and myoarchitectual patterns of the left atrial wall. Our aim was therefore to review the gross morphological and architectural features of the LA and their relations to extracardiac structures. The latter have also become relevant because extracardiac complications of AF ablation can occur, due to injuries to the phrenic and vagal plexus nerves, adjacent coronary arteries, or the esophageal wall causing devastating consequences. PMID:25057427

Sánchez-Quintana, Damián; Cabrera, José Angel; Saremi, Farhood

2014-01-01

312

Effect of prolonged space flight on cardiac function and dimensions  

NASA Technical Reports Server (NTRS)

By taking advantage of the capabilities of echocardiography to measure noninvasively left ventricular volume, stroke volume, and ejection fraction, and of the fact that the astronauts were routinely subjected to lower body negative pressure (whereby cardiac filling is progressively decreased), it was possible to construct classic ventricular function curves noninvasively, thereby obviating the difficulties encountered in comparing cardiac function at different end-diastolic volumes preflight and postflight. In this manner, the effect of an 84-day period of weightlessness on cardiac structure and function was evaluated in the Skylab 4 astronauts.

Henry, W. L.; Epstein, S. E.; Griffith, J. M.; Goldstein, R. E.; Redwood, D. R.

1977-01-01

313

Haemodynamic effects of salbutamol and nitroprusside after cardiac surgery.  

PubMed Central

The haemodynamic effects of a continuous intravenous infusion of salbutamol (15 to 30 microgram/min) and nitroprusside (50 to 100 microgram/min) were compared in 9 patients after cardiac surgical operations. The mean falls in left atrial pressure and systemic vascular resistance were similar with the two drugs but salbutamol caused a greater increase in heart rate, maximum acceleration of aortic blood flow, and maximum rate of change of left ventricular power. Because these differences would cause greater myocardial oxygen consumption with salbutamol and because the infusion of salbutamol is less easily controlled, nitroprusside is the preferred drug after cardiac operations. PMID:328027

Poole-Wilson, P A; Lewis, G; Angerpointer, T; Malcolm, A D; Williams, B T

1977-01-01

314

Transient left ventricular wall thickening in a 14-year-old girl with influenza A myocarditis.  

PubMed

We describe a case of influenza A myocarditis and transient left ventricular wall thickening in a 14-year-old girl presenting with acute heart failure. Admission echocardiogram revealed significant left ventricular hypertrophy with depressed left ventricular systolic function. The aetiology of the ventricular thickening was demonstrated to be myocardial oedema using cardiac magnetic resonance imaging. The natural course of this unusual clinical presentation of acute myocarditis and the importance of cardiac magnetic resonance imaging in this challenging clinical setting are discussed. PMID:24480544

Wittlieb-Weber, Carol A; Harris, Matthew A; Rossano, Joseph W

2015-01-01

315

Cardiac disease after radiation therapy for Hodgkin's disease: analysis of 48 patients  

SciTech Connect

Occult or overt but delayed cardiac disease after thoracic radiotherapy for Hodgkin's disease may be common. Detailed cardiac evaluations were performed in 48 patients with Hodgkin's disease at risk a mean of 97 months after radiotherapy. The study protocol included echocardiography, gated radionuclide ventriculography, and cardiac catheterization. Cardiac disease was found in 46 patients (96%) and included constrictive or occult constrictive pericarditis (24 patients), an abnormal hemodynamic response to a fluid challenge (14 patients), coronary artery disease (6 patients), and left ventricular dysfunction (2 patients). Most patients (53%) had normal echocardiograms. Gated blood pool radionuclide angiocardiography was performed in 42 patients. Excluding patients with occlusive coronary artery disease, the left ventricular ejection fraction at rest (mean 59%) and during exercise (mean 69%) was within normal limits. Thus (1) delayed cardiac disease after radiotherapy is common, (2) chronic pericardial disorders are the most frequent manifestations of this disease, and (3) the prognosis for patients who have radiation-induced cardiac disease is generally favorable.

Applefeld, M.M.; Wiernik, P.H.

1983-06-01

316

A Two-dimensional Sixteen Channel Transmit/Receive Coil Array for Cardiac MRI at 7.0 Tesla: Design, Evaluation and Application  

PubMed Central

Purpose To design, evaluate and apply a two-dimensional 16 channel transmit/receive coil array tailored for cardiac MRI at 7.0 Tesla. Material and Methods The cardiac coil array consists of 2 sections each using 8 elements arranged in a 2 × 4 array. RF safety was validated by SAR simulations. Cardiac imaging was performed using 2D CINE FLASH imaging, T2* mapping and fat-water separation imaging. The characteristics of the coil array were analyzed including parallel imaging performance, left ventricular chamber quantification and overall image quality. Results RF characteristics were found to be appropriate for all subjects included in the study. The SAR values derived from the simulations fall well in the limits of legal guidelines. The baseline SNR advantage at 7.0 T was put to use to acquire 2D CINE images of the heart with a very high spatial resolution of (1 × 1 × 4) mm3. The proposed coil array supports 1D acceleration factors of up to R=4 without impairing image quality significantly. Conclusions The 16 channel TX/RX coil has the capability to acquire high contrast and high spatial resolution images of the heart at 7.0 Tesla. PMID:22706727

Thalhammer, Christof; Renz, Wolfgang; Winter, Lukas; Hezel, Fabian; Rieger, Jan; Pfeiffer, Harald; Graessl, Andreas; Seifert, Frank; Hoffmann, Werner; von Knobelsdorff-Brenkenhoff, Florian; Tkachenko, Valeriy; Schulz-Menger, Jeanette; Kellman, Peter; Niendorf, Thoralf

2012-01-01

317

Late onset oral treatment with tranilast following large myocardial infarction has no beneficial effects on cardiac remodeling and mortality in rats  

PubMed Central

Tranilast (Tra) reduces intracardiac interstitial fibrosis in the animal models of hypertensive heart failure and diabetic cardiomyopathy by inhibiting cardiac fibroblasts. The present study examined whether Tra has long-term effects on the cardiac remodeling in the remote area of the left ventricle (LV) following myocardial infarction (MI) in the rat. Treatment with Tra (n=40; 150 mg/kg twice daily) or placebo (Plac, n=36) was started at day 28 after induction of a large MI or sham-operation (ShO, n=18) in female Lewis rats. Collagen content was determined using high-performance liquid chromatography. Large MI led to a significant hypertrophy of the two ventricles, a severe dilatation of the LV and a shift of the chamber stiffness variables in the pressure volume curves. The six-month survival rates were Tra, 62.5%; Plac, 75%; and ShO, 100%. No significant difference was identified between Tra and Plac regarding survival rate and collagen content. Treatment with the anti-inflammatory and antifibrotic drug, Tra, started four weeks after the induction of a large MI in the rat, did not attenuate or positively influence remodeling in chronic ischemic heart failure and survival. Further studies are required to explore the effects of Tra on cardiac myocytes post-MI in more detail. PMID:25371734

BETGE, STEFAN; KUNZ, CHRISTIAN; FIGULLA, HANS; JUNG, CHRISTIAN

2014-01-01

318

Wire chamber gases  

SciTech Connect

In this paper, we describe new developments in gas mixtures which have occurred during the last 3--4 years. In particular, we discuss new results on the measurement and modeling of electron drift parameters, the modeling of drift chamber resolution, measurements of primary ionization and the choice of gas for applications such as tracking, single electron detection, X-ray detection and visual imaging. In addition, new results are presented on photon feedback, breakdown and wire aging.

Va'vra, J.

1992-04-01

319

Digital optical spark chambers  

SciTech Connect

The authors have constructed and tested a prototype digital readout system for optical spark chambers using a linear, solid state (CCD) detector array. Position resolution of 0.013 mm (sigma) over a 25 centimeter field of view has been demonstrated. This technique should permit the construction of economical, light weight and low power trajectory hodoscopes for use in cosmic ray instrumentation on balloons and in spacecraft.

Evenson, P.; Tuska, E.

1989-02-01

320

Cardiac abnormalities in end stage renal failure and anaemia.  

PubMed Central

Thirteen anaemic children on dialysis were assessed to determine the incidence of cardiac changes in end stage renal failure. Nine children had an increased cardiothoracic ratio on radiography. The electrocardiogram was abnormal in every case but no child had left ventricular hypertrophy as assessed by voltage criteria. However, left ventricular hypertrophy, often gross, was found on echocardiography in 12 children and affected the interventricular septum disproportionately. Cardiac index was increased in 10 patients as a result of an increased left ventricular stroke volume rather than heart rate. Left ventricular hypertrophy was significantly greater in those on treatment for hypertension and in those with the highest cardiac index. Abnormal diastolic ventricular function was found in 6/11 children. Children with end stage renal failure have significant cardiac abnormalities that are likely to contribute to the high cardiovascular mortality in this group. Anaemia and hypertension, or its treatment, probably contribute to these changes. Voltage criteria on electrocardiogram are of no value in detecting left ventricular hypertrophy. Echocardiography must be performed, with the results corrected for age and surface area, in order to detect and follow these abnormalities. Images PMID:8323332

Morris, K P; Skinner, J R; Wren, C; Hunter, S; Coulthard, M G

1993-01-01

321

Hypothyroidism and Its Rapid Correction Alter Cardiac Remodeling  

PubMed Central

The cardiovascular effects of mild and overt thyroid disease include a vast array of pathological changes. As well, thyroid replacement therapy has been suggested for preserving cardiac function. However, the influence of thyroid hormones on cardiac remodeling has not been thoroughly investigated at the molecular and cellular levels. The purpose of this paper is to study the effect of hypothyroidism and thyroid replacement therapy on cardiac alterations. Thirty Wistar rats were divided into 2 groups: a control (n?=?10) group and a group treated with 6-propyl-2-thiouracil (PTU) (n?=?20) to induce hypothyroidism. Ten of the 20 rats in the PTU group were then treated with L-thyroxine to quickly re-establish euthyroidism. The serum levels of inflammatory markers, such as C-reactive protein (CRP), tumor necrosis factor alpha (TNF-?), interleukin 6 (IL6) and pro-fibrotic transforming growth factor beta 1 (TGF-?1), were significantly increased in hypothyroid rats; elevations in cardiac stress markers, brain natriuretic peptide (BNP) and cardiac troponin T (cTnT) were also noted. The expressions of cardiac remodeling genes were induced in hypothyroid rats in parallel with the development of fibrosis, and a decline in cardiac function with chamber dilation was measured by echocardiography. Rapidly reversing the hypothyroidism and restoring the euthyroid state improved cardiac function with a decrease in the levels of cardiac remodeling markers. However, this change further increased the levels of inflammatory and fibrotic markers in the plasma and heart and led to myocardial cellular infiltration. In conclusion, we showed that hypothyroidism is related to cardiac function decline, fibrosis and inflammation; most importantly, the rapid correction of hypothyroidism led to cardiac injuries. Our results might offer new insights for the management of hypothyroidism-induced heart disease. PMID:25333636

Itani, Tarek; Moubarak, Majed; Aftimos, Georges; Farès, Nassim

2014-01-01

322

Vibrating-chamber levitation systems  

NASA Technical Reports Server (NTRS)

Systems are described for the acoustic levitation of objects, which enable the use of a sealed rigid chamber to avoid contamination of the levitated object. The apparatus includes a housing forming a substantially closed chamber, and means for vibrating the entire housing at a frequency that produces an acoustic standing wave pattern within the chamber.

Barmatz, M. B.; Granett, D.; Lee, M. C. (inventors)

1985-01-01

323

Vertical two chamber reaction furnace  

DOEpatents

A vertical two chamber reaction furnace is disclosed. The furnace comprises a lower chamber having an independently operable first heating means for heating the lower chamber and a gas inlet means for admitting a gas to create an ambient atmosphere, and an upper chamber disposed above the lower chamber and having an independently operable second heating means for heating the upper chamber. Disposed between the lower chamber and the upper chamber is a vapor permeable diffusion partition. The upper chamber has a conveyor means for conveying a reactant there through. Of particular importance is the thallinating of long-length thallium-barium-calcium copper oxide (TBCCO) or barium-calcium-copper oxide (BCCO) precursor tapes or wires conveyed through the upper chamber to thereby effectuate the deposition of vaporized thallium (being so vaporized as the first reactant in the lower chamber at a temperature between about 700 and 800 C) on TBCCO or BCCO tape or wire (the second reactant) at its simultaneous annealing temperature in the upper chamber of about 800 to 950 C to thereby replace thallium oxide lost from TBCCO tape or wire because of the high annealing temperature or to deposit thallium on BCCO tape or wire. Continuously moving the tape or wire provides a single-step process that effectuates production of long-length TBCCO superconducting product. 2 figs.

Blaugher, R.D.

1999-03-16

324

Winged reentrant electromagnetic combustion chamber  

Microsoft Academic Search

An internal combustion engine combustion chamber suitable for electromagnetic stimulation of combustion which has been improved by the addition of combustion chamber periphery extensions (wings) filled with dielectric material. The wing dimensions and filler dielectric material are chosen to allow for specification of the chamber EM resonant frequency, preferably at a frequency in the UHF range (where low cost DC

M. A. V

1985-01-01

325

Cardiac fluid dynamics anticipates heart adaptation.  

PubMed

Hemodynamic forces represent an epigenetic factor during heart development and are supposed to influence the pathology of the grown heart. Cardiac blood motion is characterized by a vortical dynamics, and it is common belief that the cardiac vortex has a role in disease progressions or regression. Here we provide a preliminary demonstration about the relevance of maladaptive intra-cardiac vortex dynamics in the geometrical adaptation of the dysfunctional heart. We employed an in vivo model of patients who present a stable normal heart function in virtue of the cardiac resynchronization therapy (CRT, bi-ventricular pace-maker) and who are expected to develop left ventricle remodeling if pace-maker was switched off. Intra-ventricular fluid dynamics is analyzed by echocardiography (Echo-PIV). Under normal conditions, the flow presents a longitudinal alignment of the intraventricular hemodynamic forces. When pacing is temporarily switched off, flow forces develop a misalignment hammering onto lateral walls, despite no other electro-mechanical change is noticed. Hemodynamic forces result to be the first event that evokes a physiological activity anticipating cardiac changes and could help in the prediction of longer term heart adaptations. PMID:25529139

Pedrizzetti, Gianni; Martiniello, Alfonso R; Bianchi, Valter; D'Onofrio, Antonio; Caso, Pio; Tonti, Giovanni

2015-01-21

326

Absence of the Left Main Coronary Artery: MDCT Coronary Angiographic Imaging  

PubMed Central

Absent left main coronary artery (LMCA) is a rare congenital cardiac malformation. We present a case report of a 65-year-old woman with anomalous origin of the left anterior descending (LAD) and circumflex (LCx) artery separated from the left sinus of Valsalva that was diagnosed by multi-detector row computed tomography (MDCT) coronary angiography. Our case indicates that MDCT plays an important role in the diagnosis of some rare coronary anomalies.

Yilmaz-Cankaya, Bahar; Kantarci, Mecit; Yalcin, Ahmet; Durur-Karakaya, Afak; Yuce, Ihsan

2009-01-01

327

Impact of obesity and weight loss on cardiac performance and morphology in adults.  

PubMed

Obesity, particularly severe obesity is capable of producing hemodynamic alterations that predispose to changes in cardiac morphology and ventricular function. These include increased cardiac output, left ventricular hypertrophy and diastolic and systolic dysfunction of both ventricles. Facilitated by co-morbidities such as hypertension, the sleep apnea/obesity hypoventilation syndrome, and possibly certain neurohormonal and metabolic alterations, these abnormalities may predispose to left and right heart failure, a disorder known as obesity cardiomyopathy. PMID:24438730

Alpert, Martin A; Omran, Jad; Mehra, Ankit; Ardhanari, Sivakumar

2014-01-01

328

Demography of penetrating cardiac trauma.  

PubMed Central

All cases of penetrating cardiac trauma in 1985 and 1986 in Jefferson County, Alabama, where patients dying of penetrating trauma received autopsies, were retrospectively reviewed. All hospitals in the county plus the single coroner's office provided the records of the 72 patients comprising this study. Incidents occurred most often in the home or residence (70%) by a known assailant (83%) due to domestic/social disputes (73%). Frequency was greatest in the evening hours (73% between 6:00 PM and 3:00 AM), on weekends in spring and summer. Victims tended to be male (86%), black (72%), married (46%), blue collar workers (62%). There were 41 (57%) gunshot wounds, 3 (4%) shotgun wounds, and 28 (39%) stab wounds with an associated mortality rate of 97%, 100%, and 68%, respectively. Prehospital mortality rate (dead at the scene) was 54.2% (39/72), and death on arrival was 26.4% (19/72), for a combined pretreatment mortality rate of 80.6%. All patients who arrived with no vital signs died. Mortality appeared to be related to mechanism of injury, age, race, sex, vital signs on arrival, number and specific cardiac chambers injured, associated major vascular injury, hematocrit, and mode of transportation. Mortality was not related to caliber of weapon, ethanol level, transport time, time from arrival to operation, or transfusion requirements. There were only ten survivors (1 gunshot wound and 9 stab wounds), all of whom had ventricular injuries and no associated major vascular injuries. The ten survivors represented a 71.4% (10/14) salvage rate for those victims arriving with vital signs. Complications occurred in three patients. Hospitalization averaged 7.3 days in the survivors. Penetrating cardiac trauma remains a serious, socially linked disease with a high rate of mortality. Rapid transport, aggressive resuscitation and cardiorrhaphy remain the best treatment. PMID:2730180

Naughton, M J; Brissie, R M; Bessey, P Q; McEachern, M M; Donald, J M; Laws, H L

1989-01-01

329

Optimization of Cardiac Fiber Orientation for Homogeneous Fiber Strain During Ejection  

Microsoft Academic Search

The strain of muscle fibers in the heart is likely to be distributed uniformly over the cardiac walls during the ejection period of the cardiac cycle. Mathematical models of left ventricular (LV) wall mechanics have shown that the distribution of fiber strain during ejection is sensitive to the orientation of muscle fibers in the wall. In the present study, we

JM Rijcken; P. H. M. Bovendeerd; A. J. G. Schoofs; D. H. van Campen; T. Arts

1999-01-01

330

Role of the central monoaminergic mechanisms in the action of drugs on the cardiac reflexes  

Microsoft Academic Search

hic recording of the tonic activity and the reflex responses in the cardiac sympathetic nerves. For this purpose, in experiments on anesthetized cats, after thoracotomy the efferent impulses were recorded in the central end of the divided left inferior cardiac nerve. The central end of the divided tibial nerve was stimulated with rectangular electric pulses. The parameters of the stimuli

N. V. Kaverina; R. S. Mirzoyan; Yu. B. Rozonov

1967-01-01

331

Determination of cardiac size following space missions of different durations - The second manned Skylab mission  

NASA Technical Reports Server (NTRS)

A simple method to estimate cardiac size from single frontal plane chest roentgenograms has been described. Pre- and postflight chest X-rays from Apollo 17, and Skylab 2 and 3 have been analyzed for changes in the cardiac silhouette size. The data obtained from the computed cardiothoracic areal ratios compared well with the clinical cardiothoracic diametral ratios (r = .86). Though an overall postflight decrease in cardiac size is evident, the mean difference was not statistically significant (n = 8). The individual decreases in the cardiac silhouette size postflight are thought to be due to decrements in intracardiac chamber volumes rather than in myocardial muscle mass.

Nicogossian, A.; Hoffler, G. W.; Johnson, R. L.; Gowen, R. J.

1976-01-01

332

Multiple Metastatic Intracranial Lesions Associated with Left Atrial Myxoma  

PubMed Central

Summary Background One of the most common cardiac tumors is myxoma. Despite its predominantly benign course, diverse cardiological, systemic as well as neurological complications have been reported. Case Report We are the first from Poland to present the case of a patient with multiple central nervous system metastases associated with the left atrial myxoma. Various diagnostic, neuroradiological and histopathological procedures were described. The patient underwent cardiac surgery. Conclusions Follow-up studies excluded the recurrence of the heart tumor and confirmed partial resolution of brain metastases. Nevertheless, subsequent neurological assessment was advised according to the literature data and possible late relapses mainly due to cerebral emboli. PMID:25152797

Kierdaszuk, Biruta; Gogol, Pawe?; Kolasa, Anna; Maj, Edyta; Zakrzewska-Pniewska, Beata; Go??biowski, Marek; Kami?ska, Anna M.

2014-01-01

333

Multi-anode ionization chamber  

DOEpatents

The present invention includes a high-energy detector having a cathode chamber, a support member, and anode segments. The cathode chamber extends along a longitudinal axis. The support member is fixed within the cathode chamber and extends from the first end of the cathode chamber to the second end of the cathode chamber. The anode segments are supported by the support member and are spaced along the longitudinal surface of the support member. The anode segments are configured to generate at least a first electrical signal in response to electrons impinging thereon.

Bolotnikov, Aleksey E. (South Setauket, NY); Smith, Graham (Port Jefferson, NY); Mahler, George J. (Rocky Point, NY); Vanier, Peter E. (Setauket, NY)

2010-12-28

334

Cardiac compression following cardiac surgery due to unrecognised hiatus hernia.  

PubMed

A 76-year-old man who had undergone a routine coronary artery bypass grafting operation developed severe haemodynamic instability in the early postoperative period in spite of multiple inotropic supports. Due to persistent instability of haemodynamics and worsening acidosis his chest was re-explored with detection of no obvious abnormality. An intra-aortic balloon pump (IABP) was inserted for additional support. The chest had to be left open overnight and closed formally next morning. A chest X-ray at that stage showed a large hiatus hernia with huge gastric dilatation compressing the heart. Decompressions of the stomach lead to dramatic improvement in his circulatory status with rapid weaning of inotropes and IABP and he could be extubated. This case illustrates the importance of recognising the presence of hiatus hernia in preoperative chest X-ray and prophylactic NG tube insertion at the time of cardiac surgery in these cases. PMID:17881242

Devbhandari, Mohan P; Khan, Mohammad Aamir; Hooper, Timothy L

2007-11-01

335

The Clinical Benefits of Adding a Third Dimension to Assess the Left Ventricle with Echocardiography  

PubMed Central

Three-dimensional echocardiography is a novel imaging technique based on acquisition and display of volumetric data sets in the beating heart. This permits a comprehensive evaluation of left ventricular (LV) anatomy and function from a single acquisition and expands the diagnostic possibilities of noninvasive cardiology. It provides the possibility of quantitating geometry and function of LV without preestablished assumptions regarding cardiac chamber shape and allows an echocardiographic assessment of the LV that is less operator-dependent and therefore more reproducible. Further developments and improvements for widespread routine applications include higher spatial and temporal resolution to improve image quality, faster acquisition, processing and reconstruction, and fully automated quantitative analysis. At present, three-dimensional echocardiography complements routine 2DE in clinical practice, overcoming some of its limitations and offering additional valuable information that has led to recommending its use for routine assessment of the LV of patients in whom information about LV size and function is critical for their clinical management. PMID:24959374

Badano, Luigi P.

2014-01-01

336

Left ventricular endocardial surface detection based on real-time 3D echocardiographic data  

NASA Technical Reports Server (NTRS)

OBJECTIVE: A new computerized semi-automatic method for left ventricular (LV) chamber segmentation is presented. METHODS: The LV is imaged by real-time three-dimensional echocardiography (RT3DE). The surface detection model, based on level set techniques, is applied to RT3DE data for image analysis. The modified level set partial differential equation we use is solved by applying numerical methods for conservation laws. The initial conditions are manually established on some slices of the entire volume. The solution obtained for each slice is a contour line corresponding with the boundary between LV cavity and LV endocardium. RESULTS: The mathematical model has been applied to sequences of frames of human hearts (volume range: 34-109 ml) imaged by 2D and reconstructed off-line and RT3DE data. Volume estimation obtained by this new semi-automatic method shows an excellent correlation with those obtained by manual tracing (r = 0.992). Dynamic change of LV volume during the cardiac cycle is also obtained. CONCLUSION: The volume estimation method is accurate; edge based segmentation, image completion and volume reconstruction can be accomplished. The visualization technique also allows to navigate into the reconstructed volume and to display any section of the volume.

Corsi, C.; Borsari, M.; Consegnati, F.; Sarti, A.; Lamberti, C.; Travaglini, A.; Shiota, T.; Thomas, J. D.

2001-01-01

337

Review of wire chamber aging  

SciTech Connect

This paper makes an overview of the wire chamber aging problems as a function of various chamber design parameters. It emphasizes the chemistry point of view and many examples are drawn from the plasma chemistry field as a guidance for a possible effort in the wire chamber field. The paper emphasizes the necessity of variable tuning, the importance of purity of the wire chamber environment, as well as it provides a practical list of presently known recommendations. In addition, several models of the wire chamber aging are qualitatively discussed. The paper is based on a summary talk given at the Wire Chamber Aging Workshop held at LBL, Berkeley on January 16-17, 1986. Presented also at Wire Chamber Conference, Vienna, February 25-28, 1986. 74 refs., 18 figs., 11 tabs.

Va'Vra, J.

1986-02-01

338

Through the looking glass: primary epithelioid angiosarcoma in the left atrium, a unique site for a rare malignancy.  

PubMed

Malignant cardiac tumours occurring on the left side are vanishingly rare entities. We describe a case of a 73-year-old male who underwent surgery for a left-sided cardiac tumour following initial presentation with transient ischaemic attacks. In addition to the unusual presentation and subsequent metastatic pattern to the femur, the tumour's pathological diagnosis was that of an epithelioid variant of an angiosarcoma which has not been previously described in this anatomical location. PMID:23331275

Hynes, Sean O; Attah, Chike B; Ingoldsby, Helen; Kolcow, Walenty; Macneill, Briain; Veerasingam, Dave; Orosz, Zsolt

2013-07-01

339

Regression of Pathological Cardiac Hypertrophy: Signaling Pathways and Therapeutic Targets  

PubMed Central

Pathological cardiac hypertrophy is a key risk factor for heart failure. It is associated with increased interstitial fibrosis, cell death and cardiac dysfunction. The progression of pathological cardiac hypertrophy has long been considered as irreversible. However, recent clinical observations and experimental studies have produced evidence showing the reversal of pathological cardiac hypertrophy. Left ventricle assist devices used in heart failure patients for bridging to transplantation not only improve peripheral circulation but also often cause reverse remodeling of the geometry and recovery of the function of the heart. Dietary supplementation with physiologically relevant levels of copper can reverse pathological cardiac hypertrophy in mice. Angiogenesis is essential and vascular endothelial growth factor (VEGF) is a constitutive factor for the regression. The action of VEGF is mediated by VEGF receptor-1, whose activation is linked to cyclic GMP-dependent protein kinase-1 (PKG-1) signaling pathways, and inhibition of cyclic GMP degradation leads to regression of pathological cardiac hypertrophy. Most of these pathways are regulated by hypoxia-inducible factor. Potential therapeutic targets for promoting the regression include: promotion of angiogenesis, selective enhancement of VEGF receptor-1 signaling pathways, stimulation of PKG-1 pathways, and sustention of hypoxia-inducible factor transcriptional activity. More exciting insights into the regression of pathological cardiac hypertrophy are emerging. The time of translating the concept of regression of pathological cardiac hypertrophy to clinical practice is coming. PMID:22750195

Hou, Jianglong; Kang, Y. James

2012-01-01

340

Differential regulation of natriuretic peptide receptor messenger RNAs during the development of cardiac hypertrophy in the rat.  

PubMed Central

The heart expresses the three natriuretic peptide receptors (NPR), namely NPR-A, NPR-B, and NPR-C. We have examined the temporal relationship between the expression of mRNA transcripts for atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) and their receptors in the heart during the development of cardiac hypertrophy in the aortovenocaval fistula rat. Messenger RNAs were measured by cDNA amplification. Progressive cardiac hypertrophy was accompanied by increased ANP mRNA prevalence throughout the heart and increased BNP mRNA in the left atrium. The most striking observation was the gradual disappearance of NPR-C transcripts (the putative "clearance" receptor) in all chambers; this was in marked contrast to the increase in mRNA levels for NPR-A and NPR-B (the guanylyl cyclase-linked receptors). Our observations have important therapeutic implications if the transcript changes are mirrored at the receptor protein level because (a) the apparent down-regulation of NPR-C may enhance the local action of natriuretic peptides on the heart, and (b) the loss of NPR-C, particularly if it is widespread, may reduce the rate of elimination of the natriuretic peptides, restricting the therapeutic potential of specific NPR-C ligands designed to reduce peptide clearance. Images PMID:7902846

Brown, L A; Nunez, D J; Wilkins, M R

1993-01-01

341

Normal mitral annulus dynamics and its relationships with left ventricular and left atrial function.  

PubMed

Mitral annulus (MA) geometry and dynamics are crucial for preserving normal mitral valve (MV) function. Static reference values for MA parameters have been reported, but the normal MA dynamics during the entire cardiac cycle remains controversial. MV full-volume datasets were obtained by three-dimensional transthoracic echocardiography from 50 healthy volunteers (18-74 years; 31 men) to assess MA changes in size and shape during entire cardiac cycle. Using simultaneous multiplanar review, projected MA area (MAA) and circumference (MAC), antero-posterior (AP) and anterolateral-posteromedial (ALPM) diameters, and sphericity index (SphI) were obtained at: mitral valve closure (MVC), mid- and end-systole (ES), early- (EDF) and late-diastolic filling, and end-diastole. MAA and AP diameter were the most "active" parameters, changing in all reference frames (p < 0.001). MAA and AP diameter started to contract before MVC (during the left atrial contraction), reaching their minimum at MVC. Maximum MAA occurred at ES, while maximum AP diameter and SphI occurred at EDF. MAA fractional shortening was 35 ± 10 %. AP diameter change was 25 ± 10 %. MAC, ALPM and SphI showed similar patterns during left ventricular (LV) systole, and remained unchanged during diastole. Fractional change was 35 ± 10 % for MAC, and 13 ± 8 % for ALPM diameter. Our study provides the normal dynamics of the MA during the entire cardiac cycle. It reveals "pre-systolic" contraction of the MA, related to left atrial (LA) contraction, and minimal MAA during early LV systole. Therefore, the normal MA dynamics relates to a "physiologic LA-LV coupling", and a complete MA contraction requires both and properly timed LA and LV systole. PMID:25319092

Mihaila, Sorina; Muraru, Denisa; Miglioranza, Marcelo Haertel; Piasentini, Eleonora; Peluso, Diletta; Cucchini, Umberto; Iliceto, Sabino; Vinereanu, Dragos; Badano, Luigi P

2014-10-16

342

Prenatal Diagnosis of Persistent Left Superior Vena Cava and its Clinical Significance  

PubMed Central

Background: Persistent left superior vena cava (PLSVC) is a variant of systemic venous return which is observed in 0.3% of autopsies in the general population and in 4–8% of patients with congenital heart disease. Aims: To evaluate associated cardiac, extracardiac and chromosomal anomalies in prenatally diagnosed cases of PLSVC and to review their outcome. Study Design: Retrospective comparative study. Methods: The data of patients with a prenatal diagnosis of PLSVC between May 2008 and January 2013 were reviewed retrospectively. Results: Data of 31 cases were reviewed. Fifteen (48.4%) cases were associated with cardiac defects and 17 (54.8%) cases had associated extracardiac sonographic or postpartum findings. Two fetuses had karyotype anomalies. Outcome was significantly more favorable in cases not associated with cardiac defects in comparison to those associated with cardiac anomalies (84.6% vs. 33.3%, p=0.009). All cases with isolated PLSVC survived, while among the cases associated with extracardiac anomalies, with cardiac anomalies and with both extra-cardiac and cardiac anomalies, the survival rate was 75%, 50% and 22.2%, respectively. The most frequent group of cardiac anomalies associated with PLSVC was septal defects and VSD was the most common heart defect individually, being observed in nine fetuses. Conclusion: Prenatally diagnosed PLSVC is associated with cardiac and extracardiac anomalies in the majority of cases. Outcome is significantly worse if PLSVC is associated with a cardiac defect, and the prognosis is excellent in isolated cases. PMID:25207167

Esmer, Aytül Çorbac?o?lu; Yüksel, At?l; Çal?, Halime; Özsürmeli, Mehmet; Ömero?lu, Rukiye Eker; Kalelio?lu, ?brahim; Has, Recep

2014-01-01

343

Left ventricular haemangioma with papillary endothelial hyperplasia and liver involvement.  

PubMed

An intracardiac haemangioma with papillary endothelial hyperplasia (PEH) and liver involvement has not been previously reported in the English literature. This report describes a 65 year old man with a left ventricular haemangioma with PEH coexistent with multiple nodular hepatic haemangiomas. Transthoracic and transoesophageal echocardiography identified a large tumour in the left ventricular cavity with a pedicle connected to the apex. Abdominal sonography also identified multiple hyperechoic hepatic tumours. Magnetic resonance imaging showed hypervascularity of both the cardiac and hepatic lesions. The left ventricular tumour was totally resected and the liver nodules were biopsied. Tissue pathological study showed that both the left ventricular tumour and liver lesions were haemangiomas with PEH. The patient was discharged without complications postoperatively. PMID:15253991

Kan, C-D; Yae, C-T; Yang, Y-J

2004-08-01

344

The nomenclature, definition and classification of hypoplastic left heart syndrome.  

PubMed

The hypoplastic left heart syndrome encompasses a spectrum of cardiac malformations that are characterized by significant underdevelopment of the components of the left heart and the aorta, including the left ventricular cavity and mass. At the severe end of the spectrum is found the combination of aortic and mitral atresia, when the left ventricle can be close to non-existent. At the mild end are the patients with hypoplasia of the aortic and mitral valves, but without intrinsic valvar stenosis or atresia, and milder degrees of left ventricular hypoplasia. Although the majority of the patients are suitable only for functionally univentricular repair, a small minority may be candidates for biventricular repair. The nature of the syndrome was a topic for discussion at the second meeting of the International Working Group for Mapping and Coding of Nomenclatures for Paediatric and Congenital Heart Disease, the Nomenclature Working Group, held in Montreal, Canada, over the period January 17 through 19, 2003. Subsequent to these discussions, the Nomenclature Working Group was able to create a bidirectional crossmap between the nomenclature initially produced jointly on behalf of the European Association for Cardio-Thoracic Surgery and the Society of Thoracic Surgeons, and the alternative nomenclature developed on behalf of the Association for European Paediatric Cardiology. This process is a part of the overall efforts of the Nomenclature Working Group to create a comprehensive and all-inclusive international system of nomenclature for paediatric and congenital cardiac disease, the International Paediatric and Congenital Cardiac Code. In this review, we discuss the evolution of nomenclature and surgical treatment for the spectrum of lesions making up the hypoplastic left heart syndrome and its related malformations. We also present the crossmap of the associated terms for diagnoses and procedures, as recently completed by the Nomenclature Working Group. PMID:16839428

Tchervenkov, Christo I; Jacobs, Jeffrey P; Weinberg, Paul M; Aiello, Vera D; Béland, Marie J; Colan, Steven D; Elliott, Martin J; Franklin, Rodney C G; Gaynor, J William; Krogmann, Otto N; Kurosawa, Hiromi; Maruszewski, Bohdan; Stellin, Giovanni

2006-08-01

345

Spatial Repolarization Heterogeneity Detected by Magnetocardiography Correlates with Cardiac Iron Overload and Adverse Cardiac Events in Beta-Thalassemia Major  

PubMed Central

Background Patients with transfusion-dependent beta-thalassemia major (TM) are at risk for myocardial iron overload and cardiac complications. Spatial repolarization heterogeneity is known to be elevated in patients with certain cardiac diseases, but little is known in TM patients. The purpose of this study was to evaluate spatial repolarization heterogeneity in patients with TM, and to investigate the relationships between spatial repolarization heterogeneity, cardiac iron load, and adverse cardiac events. Methods and Results Fifty patients with TM and 55 control subjects received 64-channel magnetocardiography (MCG) to determine spatial repolarization heterogeneity, which was evaluated by a smoothness index of QTc (SI-QTc), a standard deviation of QTc (SD-QTc), and a QTc dispersion. Left ventricular function and myocardial T2* values were assessed by cardiac magnetic resonance. Patients with TM had significantly greater SI-QTc, SD-QTc, and QTc dispersion compared to the control subjects (all p values<0.001). Spatial repolarization heterogeneity was even more pronounced in patients with significant iron overload (T2*<20 ms, n?=?20) compared to those with normal T2* (all p values<0.001). Loge cardiac T2* correlated with SI-QTc (r?=??0.609, p<0.001), SD-QTc (r?=??0.572, p<0.001), and QTc dispersion (r?=??0.622, p<0.001), while all these indices had no relationship with measurements of the left ventricular geometry or function. At the time of study, 10 patients had either heart failure or arrhythmia. All 3 indices of repolarization heterogeneity were related to the presence of adverse cardiac events, with areas under the receiver operating characteristic curves (ranged between 0.79 and 0.86), similar to that of cardiac T2*. Conclusions Multichannel MCG demonstrated that patients with TM had increased spatial repolarization heterogeneity, which is related to myocardial iron load and adverse cardiac events. PMID:24475137

Chen, Chun-An; Lu, Meng-Yao; Peng, Shinn-Forng; Lin, Kai-Hsin; Chang, Hsiu-Hao; Yang, Yung-Li; Jou, Shiann-Tarng; Lin, Dong-Tsamn; Liu, Yen-Bin; Horng, Herng-Er; Yang, Hong-Chang; Wang, Jou-Kou; Wu, Mei-Hwan; Wu, Chau-Chung

2014-01-01

346

Minimal role of nitric oxide in basal coronary flow regulation and cardiac energetics of blood-perfused isolated canine heart.  

PubMed Central

1. The role of nitric oxide (NO) in the regulation of basal coronary perfusion and ventricular chamber energetics was studied in isovolumetrically contracting isolated blood-perfused canine hearts. Hearts were cross-perfused by a donor animal prior to isolation, and chamber volume controlled by a servo-pump. Coronary sinus flow and arterial-coronary sinus oxygen difference were measured to determine energetic efficiency. 2. NO synthase (NOS) was competitively inhibited by NG-monomethyl-L-arginine (L-NMMA; 0.5 mg kg-1, intracoronary), resulting in a reduction of acetylcholine (50 micrograms min-1)-induced flow augmentation from 143 to 62% (P < 0.001). 3. NOS inhibition had no significant effect on basal coronary flow. Coronary pressure-flow relationships were determined at a constant cardiac workload by varying mean perfusion pressure between 20 and 150 mmHg. Neither the shape of the relationship, nor the low-pressure value at which flow regulation was substantially diminished were altered by NOS inhibition. 4. Myocardial efficiency was assessed by the relationship between myocardial oxygen consumption and total pressure-volume area (PVA), with cavity volume altered to generate varying PVAs. This relative load-independent measure of energetic efficiency was minimally altered by NOS inhibition. 5. These results contrast with isolated crystalloid-perfused heart experiments and suggest that in hearts with highly controlled ventricular loading and whole-blood perfusion, effects of basal NO production on coronary perfusion and left ventricular energetics are minimal. PMID:8866868

Saeki, A; Recchia, F A; Senzaki, H; Kass, D A

1996-01-01

347

Mathematical modeling applied to the left ventricle of heart  

E-print Network

Background: How can mathematics help us to understand the mechanism of the cardiac motion? The best known approach is to take a mathematical model of the fibered structure, insert it into a more-or-less complex model of cardiac architecture, and then study the resulting fibers of activation that propagate through the myocardium. In our paper, we have attempted to create a novel software capable of demonstrate left ventricular (LV) model in normal hearts. Method: Echocardiography was performed on 70 healthy volunteers. Data evaluated included: velocity (radial, longitudinal, rotational and vector point), displacement (longitudinal and rotational), strain rate (longitudinal and circumferential) and strain (radial, longitudinal and circumferential) of all 16 LV myocardial segments. Using these data, force vectors of myocardial samples were estimated by MATLAB software, interfaced in the echocardiograph system. Dynamic orientation contraction (through the cardiac cycle) of every individual myocardial fiber could ...

Ranjbar, Saeed

2014-01-01

348

Left ventricular hypertrabeculation/noncompaction in hereditary inclusion body myopathy.  

PubMed

Left ventricular hypertrabeculation (LVHT) also known as noncompaction has not been reported in association with hereditary inclusion body myopathy (IBM). In a 62 year old Caucasian male, with a history of muscle stiffness, myalgias, recurrent hyper-creatin-kinase(CK)-aemia, muscle cramps particularly during cold, polyarthralgias, a family history positive for muscle cramping and muscle disease, normal clinical neurologic examination, and myogenic needle EMG, muscle biopsy was indicative of hereditary IBM. Cardiologic investigations revealed arterial hypertension, left anterior hemiblock, slight myocardial thickening, and surprisingly lone LVHT. LVHT was not associated with arrhythmias, systolic dysfunction, or cardioembolic events, No neurological or cardiac therapy was necessary. During a follow-up of 18 months neither the neurological nor the cardiologic abnormalities progressed. LVHT may also occur in patients with IBM. Patients with hereditary IBM should be investigated for cardiac involvement, which may manifest not only as myocardial damage but also as impulse propagation abnormalities. PMID:19900728

Finsterer, Josef; Stöllberger, Claudia; Höftberger, Romana

2011-07-15

349

Effects of intracoronary and intravenous amrinone infusions in patients with cardiac failure and patients with near normal cardiac function.  

PubMed Central

The effects of intracoronary and intravenous infusions of amrinone were studied to distinguish the drug's direct cardiac actions from its peripheral vascular and neuroendocrine properties. Intracoronary infusions of amrinone were found to have no haemodynamic effect other than producing a slight reduction in the left ventricular ejection fraction and some suggestion of coronary vasodilatation in patients with impaired left ventricular function. They did not improve contractility, cardiac output, or filling pressures and had no significant effect on myocardial metabolism, although therapeutic concentrations of the drug were detected in coronary sinus blood. Intravenously administered amrinone reduced filling pressures and improved the cardiac index in all patients, but haemodynamic improvements were most pronounced in the patients with the worst cardiac function. These changes were accompanied by improvements in the indices of contractility only in patients in whom alterations in concentrations of free fatty acid, glycerol, and glucose suggested peripheral catecholamine release. In the patients with the best basal cardiac function intravenously administered amrinone produced a reduction in myocardial work and evidence of myocardial ischaemia, as a result of excessive reduction of coronary perfusion pressure and increased heart rate, without any appreciable increase in cardiac index. It is concluded that, at the concentrations of the drug that can be achieved in man without adverse effects, amrinone has no direct positive inotropic effect. Haemodynamic changes are predominantly the result of vasodilatation, although catecholamines may be released in some patients. PMID:3994862

Wilmshurst, P T; Thompson, D S; Juul, S M; Dittrich, H C; Dawson, J R; Walker, J M; Jenkins, B S; Coltart, D J; Webb-Peploe, M M

1985-01-01

350

Iran Chamber Society  

NSDL National Science Digital Library

In 2001, the Iran Chamber Society was created in order to provide a non-partisan, non-commercial, comprehensive source of information on Iran. The website's "About Us" section states that their aim is to "create a global awareness about Iranian society and eradicate the misunderstandings and misconceptions about Iranian society, and to play an educational role as well." Visitors will find the website divided up into "Art and Culture", "History", "Society" and "Iran's Guide". The "Exhibitions and Conferences" link on the right side of the homepage leads visitors to a number of exhibitions, including the fascinating "Artistic Murals of Tehran's Metro Stations", which offers a dozen pictures of the beautifully handcrafted murals made of pottery, metal, cement and other materials. The "History" section offers pictures and documents, including some disturbing graphic photos from the Iran-Iraq War in 1980-1988 that appear at the end of the Historic Periods and Events section.

351

Mush Column Magma Chambers  

NASA Astrophysics Data System (ADS)

Magma chambers are a necessary concept in understanding the chemical and physical evolution of magma. The concept may well be similar to a transfer function in circuit or time series analysis. It does what needs to be done to transform source magma into eruptible magma. In gravity and geodetic interpretations the causative body is (usually of necessity) geometrically simple and of limited vertical extent; it is clearly difficult to `see' through the uppermost manifestation of the concentrated magma. The presence of plutons in the upper crust has reinforced the view that magma chambers are large pots of magma, but as in the physical representation of a transfer function, actual magma chambers are clearly distinct from virtual magma chambers. Two key features to understanding magmatic systems are that they are vertically integrated over large distances (e.g., 30-100 km), and that all local magmatic processes are controlled by solidification fronts. Heat transfer considerations show that any viable volcanic system must be supported by a vertically extensive plumbing system. Field and geophysical studies point to a common theme of an interconnected stack of sill-like structures extending to great depth. This is a magmatic Mush Column. The large-scale (10s of km) structure resembles the vertical structure inferred at large volcanic centers like Hawaii (e.g., Ryan et al.), and the fine scale (10s to 100s of m) structure is exemplified by ophiolites and deeply eroded sill complexes like the Ferrar dolerites of the McMurdo Dry Valleys, Antarctica. The local length scales of the sill reservoirs and interconnecting conduits produce a rich spectrum of crystallization environments with distinct solidification time scales. Extensive horizontal and vertical mushy walls provide conditions conducive to specific processes of differentiation from solidification front instability to sidewall porous flow and wall rock slumping. The size, strength, and time series of eruptive behavior of the system, coupled with these processes, define the fundamental compositional and dynamic diversity of the Mush Column. In some ways it functions like a complex musical instrument. Entrainment, transport, and sorting of cumulate crystals as a function of repose time and the local flux intensity also contribute to the basic compositional diversity of the system. In the Ferrar dolerite system, about 104 km3 of dolerite is distributed throughout a fir-tree like stack of 4 or 5 extensive 300-750 m thick sills. The lowest sill contains a vast tongue of entrained orthopyroxene (opx) cumulates emplaced with the sill itself. The bulk sill composition varies from 20 pc MgO in the tongue center to 7 pc in the leading tip and margins of the sill, which itself defines the compositional spectrum of the whole complex and is remarkably similar to that exhibited by Hawaii. Relative sorting of large (1-50 mm) opx and small (1-3 mm) plagioclase due to kinetic sieving in the tongue produces pervasive anorthosite stringers. Through local ponding this has culminated in the formation of a small, well-formed layered intrusion consisting of alternating layers of orthopyroxenite and anorthosite. Upwards in the system the sills become progressively depleted in MgO and temporally and spatially contiguous flood basalts are low MgO tholeiites with no sign of opx cumulates. The size, extent, number of sills, and the internal structure of individual sills suggest a rhythm of injection similar to that of volcanic episodes. The continued horizontal stretching of a system of this type would lead to processes as recorded by ophiolites, and the repeated injection into a single reservoir would undoubtedly lead to a massive layered intrusion or to a series of high-level nested plutons.

Marsh, B. D.

2002-12-01

352

Isolation of the left common carotid or left innominate artery.  

PubMed Central

Isolation of the left common carotid or left innominate artery from the aortic arch is rare. A six week malformed infant with a right aortic arch had isolation of a left innominate artery and connection to the pulmonary artery by a left ductus arteriosus. A right ductus arteriosus had been ligated. Another infant with a right aortic arch and ostium primum atrial septal defect was shown to have an aberrant left subclavian artery arising from the lower descending aorta. The left common carotid artery filled retrogradely and drained into the pulmonary artery by a left ductus arteriosus. This abnormality has not been reported before. Images Fig 1 Fig 2 PMID:3304368

Fong, L V; Venables, A W

1987-01-01

353

Portable electron beam weld chamber  

NASA Technical Reports Server (NTRS)

Development and characteristics of portable vacuum chamber for skate type electron beam welding are discussed. Construction and operational details of equipment are presented. Illustrations of equipment are provided.

Lewis, J. R.; Dimino, J. M.

1972-01-01

354

Cardiac Procedures and Surgeries  

MedlinePLUS

Cardiac Procedures and Surgeries Updated:Oct 24,2014 If you've had a heart attack, you may have already had certain procedures to ... artery disease (CAD) you have. Cardiac Procedures and Surgeries Angioplasty Also known as Percutaneous Coronary Interventions [PCI], ...

355

Cardiac sarcoidosis: contemporary review.  

PubMed

Cardiac sarcoidosis can occur in up to 25% of patients with sarcoidosis in other organ systems and may present with conduction abnormalities, ventricular arrhythmias, or heart failure. This review will summarize the state of current knowledge and key questions that remain to be answered. Because cardiac sarcoidosis is a rare, complex disease, the most meaningful research will include interdisciplinary, multicenter collaborations. PMID:25231794

Kron, Jordana; Ellenbogen, Kenneth A

2015-01-01

356

Differential cardiac responses to unilateral sympathetic nerve stimulation in the isolated innervated rabbit heart  

Microsoft Academic Search

The heart receives both a left and right sympathetic innervation. Currently there is no description of an in vitro whole heart preparation for comparing the influence of each sympathetic supply on cardiac function. The aim was to establish the viability of using an in vitro model to investigate the effects of left and right sympathetic chain stimulation (LSS\\/RSS). For this

James Winter; Abdul Samed Tanko; Kieran E. Brack; John H. Coote; G. André Ng

357

Evaluation of Left Ventricular Diastolic Function Using Acoustic Quantification  

Microsoft Academic Search

\\u000a The concept that heart failure and significant cardiac impairment could be attributed to diastolic dysfunction was first introduced\\u000a by Dougherty et al. [1] in 1984. In his study of 188 patients with heart failure, 36% of the patients had normal or near normal left ventricular\\u000a (LV) systolic function, with ejection fractions of 0.45 or greater. Echocardiographic findings in these patients

Sandra C. Gan; Richard L. Popp

358

Cardiac Resynchronization Therapy Upregulates Cardiac Autonomic Control  

PubMed Central

Objective: To determine the effect of cardiac resynchronization therapy (CRT) on sympathetic nervous function in heart failure (HF). Background: Neurohormonal dysregulation and cardiac autonomic dysfunction are associated with HF and contribute to HF progression and its poor prognosis. We hypothesized that mechanical resynchronization improves cardiac sympathetic function in HF. Methods: Sixteen consecutive patients receiving CRT for advanced cardiomyopathy and 10 controls were included in this prospective study. NYHA class, 6-minute walk distance, echocardiographic parameters, plasma norepinephrine (NE) were assessed at baseline, 3-month and 6-month follow-up. Cardiac sympathetic function was determined by 123iodine metaiodobenzylguanidine (123I-MIBG) scintigraphy and 24-hour ambulatory electrocardiography. Results: Along with improvement in NYHA class (3.1 ± 0.3 to 2.1 ± 0.4, P < 0.001) and LVEF (23 ± 6% to 33 ± 12%, P < 0.001 delayed heart/mediastinum (H/M) 123 I-MIBG ratio increased significantly (1.8 ± 0.7 to 2.1 ± 0.6, P = 0.04) while the H/M 123I-MIBG washout rate decreased significantly (54 ± 25% to 34± 24%, P = 0.01) from baseline to 6-month follow-up. The heart rate variability (HRV) measured in SD of normal-to-normal intervals also increased significantly from baseline (82 ± 30 ms) to follow-up (111 ± 32 ms, P = 0.04). The improvement in NYHA after CRT was significantly associated with baseline 123I-MIBG H/M washout rate (r = 0.65, P = 0.03). The improvement in LVESV index was associated with baseline 123I-MIBG delayed H/M ratio (r = ?0.67, P = 0.02) and H/M washout rate (r = 0.65, P = 0.03). Conclusion: After CRT, improvements in cardiac symptoms and LV function were accompanied by rebalanced cardiac autonomic control as measured by 123I-MIBG and HRV. PMID:18479331

CHA, YONG-MEI; OH, JAE; MIYAZAKI, CHINAMI; HAYES, DAVID L.; REA, ROBERT F.; SHEN, WIN-KUANG; ASIRVATHAM, SAMUEL J.; KEMP, BRAD J.; HODGE, DAVID O.; CHEN, PENG-SHENG; CHAREONTHAITAWEE, PANITHAYA

2009-01-01

359

HATCH CONNECTING TEMPERED AIR CHAMBER AND HOT AIR CHAMBER OF ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

HATCH CONNECTING TEMPERED AIR CHAMBER AND HOT AIR CHAMBER OF PLENUM WITH ATTACHED DRAFT REGULATOR. - Hot Springs National Park, Bathhouse Row, Superior Bathhouse: Mechanical & Piping Systems, State Highway 7, 1 mile north of U.S. Highway 70, Hot Springs, Garland County, AR

360

Cardiac Hegemony of Senescence  

PubMed Central

Cardiac senescence and age-related disease development have gained general attention and recognition in the past decades due to increased accessibility and quality of health care. The advancement in global civilization is complementary to concerns regarding population aging and development of chronic degenerative diseases. Cardiac degeneration has been rigorously studied. The molecular mechanisms of cardiac senescence are on multiple cellular levels and hold a multilayer complexity level, thereby hampering development of unambiguous treatment protocols. In particular, the synergistic exchange of the senescence phenotype through a senescence secretome between myocytes and stem cells appears complicated and is of great future therapeutic value. The current review article will highlight hallmarks of senescence, cardiac myocyte and stem cell senescence, and the mutual exchange of senescent secretome. Future cardiac cell therapy approaches require a comprehensive understanding of myocardial senescence to improve therapeutic efficiency as well as efficacy. PMID:24349878

Siddiqi, Sailay; Sussman, Mark A.

2013-01-01

361

Cardiac Hegemony of Senescence.  

PubMed

Cardiac senescence and age-related disease development have gained general attention and recognition in the past decades due to increased accessibility and quality of health care. The advancement in global civilization is complementary to concerns regarding population aging and development of chronic degenerative diseases. Cardiac degeneration has been rigorously studied. The molecular mechanisms of cardiac senescence are on multiple cellular levels and hold a multilayer complexity level, thereby hampering development of unambiguous treatment protocols. In particular, the synergistic exchange of the senescence phenotype through a senescence secretome between myocytes and stem cells appears complicated and is of great future therapeutic value. The current review article will highlight hallmarks of senescence, cardiac myocyte and stem cell senescence, and the mutual exchange of senescent secretome. Future cardiac cell therapy approaches require a comprehensive understanding of myocardial senescence to improve therapeutic efficiency as well as efficacy. PMID:24349878

Siddiqi, Sailay; Sussman, Mark A

2013-12-01

362

No Baby Left behind  

ERIC Educational Resources Information Center

"No Baby Left Behind" was created to have an impact on the school readiness of children in the community today and in the future. Each year, there are an increasing number of students who have learning difficulties. Many of these problems are preventable. Accidents, poor nutrition (of the mother and/or child), drug use, alcohol use, and lack of…

Blanton, Dorothy

2007-01-01

363

Accountability Left Behind  

ERIC Educational Resources Information Center

This article describes the reversal of the dismissal of an "unfunded-mandates" challenge to the No Child Left Behind Act (NCLB) brought by the National Education Association (NEA), several of its affiliates, and a number of school districts by the United States Court of Appeals for the Sixth Circuit. The decision in "School District of the City of…

Testani, Rocco E.; Mayes, Joshua A.

2008-01-01

364

The Children Left Behind  

ERIC Educational Resources Information Center

This article explores some of the deficits in our educational system in regard to non-hearing students. It has become agonizingly clear that non-hearing students are being left out of the gallant sweep to enrich our children's educations. The big five areas of literacy, at best, present unique challenges for non-hearing students and, in some…

Gillard, Sarah A.; Gillard, Sharlett

2012-01-01

365

No School Left Unscathed  

ERIC Educational Resources Information Center

The author maintains that the No Child Left Behind (NCLB) Act of 2001 brands good schools with "failing" labels, places the heaviest burdens on states that were already striving to meet challenging education goals, imposes inflexible rules, and fails to make good on promises to pay for programs that would help struggling schools meet the demands…

Allen, Tom

2004-01-01

366

Assessing the wall motion of pulmonary veins of the left atrium  

Microsoft Academic Search

Atrial fibrillation is caused by some excited cardiac myocardium re-stimulated by the recurrent impulse that made the left atrium contraction irregularly. The changes of cardiac patterns could be recorded by the CT scan of the multi-slices and multi-frame technology. The abnormal rhythmic wall motion can be analyzed between the systolic of atrium and diastolic of atrium. This study has developed

W. C. Hu; J. J. Wang; H. M. Tsao; L. Y. Shyu

2008-01-01

367

Compensatory mechanisms for cardiac dysfunction in myocardial infarction.  

PubMed

Loss of contractile myocardial tissue by myocardial infarction would result in depressed cardiac output if compensatory mechanisms would not be operative. Frank-Straub-Starling-mechanism and increased heart rate and contractility due to sympathetic stimulation are unlikely to chronically compensate for cardiac dysfunction. Structural left ventricular dilatation may be compensatory, but results in increased wall stress and, ultimately, in progressive dilatation and heart failure. In patients with myocardial infarction, we have shown left-ventricular dilatation in dependence of infarct size and time after infarction. Dilatation is compensatory first and normalizes stroke volume. However, left ventricular dilatation progresses without further hemodynamic profit and, thus, may participate in development of heart failure. PMID:1838246

Ertl, G; Gaudron, P; Eilles, C; Schorb, W; Kochsiek, K

1991-01-01

368

Gross anatomy of the cardiac blood vessels in the North American beaver (Castor canadensis).  

PubMed

The cardiac arteries and veins are described in the North American beaver (Castor canadensis) following the injection of the vessels of 15 hearts with either latex, vinyl plastic or barium sulfate. The left coronary artery gives off the typical circumflex and paraconal interventricular branches which supply the left atrium and ventricle and part of the right ventricle and interventricular septum. The right coronary artery vascularizes the right atrium and ventricule and by means of its subsinuosal interventricular branch, part of the left ventricle and interventricular septum. The paraconal interventricular branch of the left coronary artery lies within the myocardium and is not visible on the surface of the heart. There are no intercoronary anastomoses between the right and left vessels. The major cardiac veins open into the terminal end of the left cranial vena cava. Unlike the arteries, there are venous anastomoses interconnecting the great cardiac vein and the middle cardiac vein. It is concluded that the cardiac blood vessels in Castor canadensis are typically mammalian and resemble those of both land and aquatic mammals. PMID:7305001

Bisaillon, A

1981-01-01

369

Levoatriocardinal Vein: An Unusual Cause of Right-to-Left Shunting  

PubMed Central

We present a case demonstrating an anomalous vessel connecting the left brachiocephalic vein and the left superior pulmonary vein, found incidentally on computed tomography (CT) imaging. This pulmonary–systemic venous connection, known as a levoatriocardinal vein, is a rare anomaly. In previous descriptions, this vessel has typically been associated with left-to-right shunt. Here, we describe the magnetic resonance imaging (MRI) and CT findings in a case with right-to-left shunting through the anomalous vessel likely secondary to elevated right cardiac pressure.

Shet, Nilima; Maldjian, Pierre

2014-01-01

370

Indexed effective orifice area after mechanical aortic valve replacement does not affect left ventricular mass regression in elderly  

Microsoft Academic Search

Objective: After aortic valve replacement, the effects of a small functional prosthesis on the extent and pattern of regression of left ventricular hypertrophy and on clinical outcomes may be less significant in older patients with low cardiac output requirements. The objective of this study was therefore to determine whether patient-prosthesis mismatch affects left ventricular mass regression in the elderly. Methods:

Antonino Roscitano; Umberto Benedetto; Alfonso Sciangula; Eusebio Merico; Filippo Barberi; Roberto Bianchini; Euclide Tonelli; Riccardo Sinatra

2010-01-01

371

Indexed effective orifice area after mechanical aortic valve replacement does not affect left ventricular mass regression in elderly  

Microsoft Academic Search

Objective: After aortic valve replacement, the effects of a small functional prosthesis on the extent and pattern of regression of left ventricular hypertrophy and on clinical outcomes may be less significant in older patients with low cardiac output requirements. The objective of this study was therefore to determine whether patient-prosthesis mismatch affects left ventricular mass regression in the elderly. Methods:

Antonino Roscitano; Umberto Benedetto; Alfonso Sciangula; Eusebio Merico; Filippo Barberi; Roberto Bianchini; Euclide Tonelli; Riccardo Sinatra

2006-01-01

372

Telmisartan regresses left ventricular hypertrophy in caveolin-1 deficient mice  

PubMed Central

The role of angiotensin II (Ang II) in promoting cardiac hypertrophy is well known, however the role of the Ang II in a spontaneous model of hypertrophy in mice lacking the protein caveolin-1 (Cav- KO) has not been explored. In this study, WT and Cav-1 KO mice were treated with angiotensin receptor blocker (ARB), telmisartan, and cardiac function assessed by echocardiography. Treatment of Cav-1 KO mice with telmisartan significantly improved cardiac function compared to age-matched, vehicle treated Cav-1 KO mice, while telmisartan did not affected cardiac function in WT mice. Both left ventricular (LV) weight to body weight ratios and LV to tibial length ratios were also reverted by telmisartan in Cav-1 KO but not WT mice. LV hypertrophy was associated with increased expression of natriuretic peptides-A and –B, ?-myosin heavy chain and TGF-? and telmisartan treatment normalized the expression of these genes. Telmisartan reduced the expression of collagen genes (Col1A and Col3A) and associated perivascular fibrosis in intramyocardial vessels in Cav-1 KO mice. In conclusion, telmisartan treatment reduces indexes of cardiac hypertrophy in this unique genetic model of spontaneous LV hypertrophy. PMID:20585312

Kreiger, Marta H; Di Lorenzo, Annarita; Teutsch, Christine; Kauser, Katalin; Sessa, William C.

2011-01-01

373

Ion chamber based neutron detectors  

SciTech Connect

A neutron detector with monolithically integrated readout circuitry, including: a bonded semiconductor die; an ion chamber formed in the bonded semiconductor die; a first electrode and a second electrode formed in the ion chamber; a neutron absorbing material filling the ion chamber; and the readout circuitry which is electrically coupled to the first and second electrodes. The bonded semiconductor die includes an etched semiconductor substrate bonded to an active semiconductor substrate. The readout circuitry is formed in a portion of the active semiconductor substrate. The ion chamber has a substantially planar first surface on which the first electrode is formed and a substantially planar second surface, parallel to the first surface, on which the second electrode is formed. The distance between the first electrode and the second electrode may be equal to or less than the 50% attenuation length for neutrons in the neutron absorbing material filling the ion chamber.

Derzon, Mark S; Galambos, Paul C; Renzi, Ronald F

2014-12-16

374

Anterior chamber depth during hemodialysis  

PubMed Central

Background Exacerbation of chronic glaucoma or acute glaucoma is occasionally observed in patients undergoing hemodialysis (HD) because of anterior chamber depth changes during this therapy. Purpose To evaluate anterior chamber depth and axial length in patients during HD sessions. Methods A total of 67 eyes of 35 patients were prospectively enrolled. Axial length and anterior chamber depth were measured using ultrasonic biometry, and these measures were evaluated at three different times during HD sessions. Body weight and blood pressure pre- and post-HD were also measured. Results There was no difference in the axial length between the three measurements (P = 0.241). We observed a significantly decreased anterior chamber depth (P = 0.002) during HD sessions. Conclusion Our results support the idea that there is a change in anterior chamber depth in HD sessions. PMID:23976841

Gracitelli, Carolina Pelegrini Barbosa; Stefanini, Francisco Rosa; Penha, Fernando; Góes, Miguel Ângelo; Draibe, Sérgio Antonio; Canziani, Maria Eugênia; Junior, Augusto Paranhos

2013-01-01

375

Cardiac CT scan for preoperative planning in a patient with bilateral subclavian stenosis needing coronary artery bypass.  

PubMed

A 61-year-old male vasculopath presented for coronary revascularization and was found to have high-grade bilateral subclavian artery stenosis. The adequacy of the left internal mammary artery for bypass to the left anterior descending artery was in question. Rather than assessing the left internal mammary artery intraoperatively, we performed a preoperative cardiac computed tomography (CT) angiogram. This showed that the free left internal mammary artery was a suitable conduit and the procedure was performed expeditiously. Therefore, cardiac CT angiography is a noninvasive tool for preoperative planning in coronary revascularization. PMID:19267832

Moussa, Fuad; Kumar, Pawan; Pen, Visal

2009-01-01

376

Successful resuscitation of a patient who developed cardiac arrest from pulsed saline bacitracin lavage during thoracic laminectomy and fusion  

Microsoft Academic Search

A patient with a history of T12 burst fracture caused by a fall, and with progressive weakness and sensory loss in the left leg, survived a cardiac arrest after pulsed saline bacitracin lavage irrigation during a posterior spinal fusion.

Steven B. Greenberg; Mark Deshur; Yevgeniy Khavkin; Elden Karaikovic; Jeffery Vender

2008-01-01

377

Patient-specific left atrial wall-thickness measurement and visualization for radiofrequency ablation  

NASA Astrophysics Data System (ADS)

INTRODUCTION: For radiofrequency (RF) catheter ablation of the left atrium, safe and effective dosing of RF energy requires transmural left atrium ablation without injury to extra-cardiac structures. The thickness of the left atrial wall may be a key parameter in determining the appropriate amount of energy to deliver. While left atrial wall-thickness is known to exhibit inter- and intra-patient variation, this is not taken into account in the current clinical workflow. Our goal is to develop a tool for presenting patient-specific left atrial thickness information to the clinician in order to assist in the determination of the proper RF energy dose. METHODS: We use an interactive segmentation method with manual correction to segment the left atrial blood pool and heart wall from contrast-enhanced cardiac CT images. We then create a mesh from the segmented blood pool and determine the wall thickness, on a per-vertex basis, orthogonal to the mesh surface. The thickness measurement is visualized by assigning colors to the vertices of the blood pool mesh. We applied our method to 5 contrast-enhanced cardiac CT images. RESULTS: Left atrial wall-thickness measurements were generally consistent with published thickness ranges. Variations were found to exist between patients, and between regions within each patient. CONCLUSION: It is possible to visually determine areas of thick vs. thin heart wall with high resolution in a patient-specific manner.

Inoue, Jiro; Skanes, Allan C.; White, James A.; Rajchl, Martin; Drangova, Maria

2014-03-01

378

Proton beam monitor chamber calibration.  

PubMed

The first goal of this paper is to clarify the reference conditions for the reference dosimetry of clinical proton beams. A clear distinction is made between proton beam delivery systems which should be calibrated with a spread-out Bragg peak field and those that should be calibrated with a (pseudo-)monoenergetic proton beam. For the latter, this paper also compares two independent dosimetry techniques to calibrate the beam monitor chambers: absolute dosimetry (of the number of protons exiting the nozzle) with a Faraday cup and reference dosimetry (i.e. determination of the absorbed dose to water under IAEA TRS-398 reference conditions) with an ionization chamber. To compare the two techniques, Monte Carlo simulations were performed to convert dose-to-water to proton fluence. A good agreement was found between the Faraday cup technique and the reference dosimetry with a plane-parallel ionization chamber. The differences-of the order of 3%-were found to be within the uncertainty of the comparison. For cylindrical ionization chambers, however, the agreement was only possible when positioning the effective point of measurement of the chamber at the reference measurement depth-i.e. not complying with IAEA TRS-398 recommendations. In conclusion, for cylindrical ionization chambers, IAEA TRS-398 reference conditions for monoenergetic proton beams led to a systematic error in the determination of the absorbed dose to water, especially relevant for low-energy proton beams. To overcome this problem, the effective point of measurement of cylindrical ionization chambers should be taken into account when positioning the reference point of the chamber. Within the current IAEA TRS-398 recommendations, it seems advisable to use plane-parallel ionization chambers-rather than cylindrical chambers-for the reference dosimetry of pseudo-monoenergetic proton beams. PMID:25109620

Gomà, C; Lorentini, S; Meer, D; Safai, S

2014-09-01

379

Proton beam monitor chamber calibration  

NASA Astrophysics Data System (ADS)

The first goal of this paper is to clarify the reference conditions for the reference dosimetry of clinical proton beams. A clear distinction is made between proton beam delivery systems which should be calibrated with a spread-out Bragg peak field and those that should be calibrated with a (pseudo-)monoenergetic proton beam. For the latter, this paper also compares two independent dosimetry techniques to calibrate the beam monitor chambers: absolute dosimetry (of the number of protons exiting the nozzle) with a Faraday cup and reference dosimetry (i.e. determination of the absorbed dose to water under IAEA TRS-398 reference conditions) with an ionization chamber. To compare the two techniques, Monte Carlo simulations were performed to convert dose-to-water to proton fluence. A good agreement was found between the Faraday cup technique and the reference dosimetry with a plane-parallel ionization chamber. The differences—of the order of 3%—were found to be within the uncertainty of the comparison. For cylindrical ionization chambers, however, the agreement was only possible when positioning the effective point of measurement of the chamber at the reference measurement depth—i.e. not complying with IAEA TRS-398 recommendations. In conclusion, for cylindrical ionization chambers, IAEA TRS-398 reference conditions for monoenergetic proton beams led to a systematic error in the determination of the absorbed dose to water, especially relevant for low-energy proton beams. To overcome this problem, the effective point of measurement of cylindrical ionization chambers should be taken into account when positioning the reference point of the chamber. Within the current IAEA TRS-398 recommendations, it seems advisable to use plane-parallel ionization chambers—rather than cylindrical chambers—for the reference dosimetry of pseudo-monoenergetic proton beams.

Gomà, C.; Lorentini, S.; Meer, D.; Safai, S.

2014-09-01

380

Cardiac Parasitic Infection in Trichinellosis Associated with Right Ventricle Outflow Tract Obstruction  

PubMed Central

Here, we present a rare case of cardiac parasitic infection found in an adult female patient who had the symptoms of dyspnea upon exertion. She was diagnosed with a double-chambered right ventricle due to infundibular hypertrophy confirmed by transthoracic echocardiography and cardiac computed tomography. We performed surgery of infundibulectomy around the pulmonary valve. In the end, histopathological findings of the resected infundibular muscle demonstrated trichinellosis, a type of roundworm infection. PMID:24782966

Bang, Seung Ho; Park, Jae Bum; Chee, Hyun Keun; Kim, Jun Seok; Ko, Sung Min; Kim, Wan Seop

2014-01-01

381

Absence of heartbeat in the Xenopus tropicalis mutation muzak is caused by a nonsense mutation in cardiac myosin myh6  

PubMed Central

Mechanisms coupling heart function and cardiac morphogenesis can be accessed in lower vertebrate embryos that can survive to swimming tadpole stages on diffused oxygen. Forward genetic screens in Xenopus tropicalis have identified more than 80 mutations affecting diverse developmental processes, including cardiac morphogenesis and function. In the first positional cloning of a mutation in X. tropicalis, we show that non-contractile hearts in muzak (muz) embryos are caused by a premature stop codon in the cardiac myosin heavy chain gene myh6. The mutation deletes the coiled-coil domain responsible for polymerization into thick filaments, severely disrupting the cardiomyocyte cytoskeleton. Despite the lack of contractile activity and absence of a major structural protein, early stages of cardiac morphogenesis including looping and chamber formation are grossly normal. Muz hearts subsequently develop dilated chambers with compressed endocardium and fail to form identifiable cardiac valves and trabeculae. PMID:19769958

Abu-Daya, Anita; Sater, Amy K.; Wells, Dan E.; Mohun, Timothy J.; Zimmerman, Lyle B.

2009-01-01

382

Molecular Basis of Cardiac Myxomas  

PubMed Central

Cardiac tumors are rare, and of these, primary cardiac tumors are even rarer. Metastatic cardiac tumors are about 100 times more common than the primary tumors. About 90% of primary cardiac tumors are benign, and of these the most common are cardiac myxomas. Approximately 12% of primary cardiac tumors are completely asymptomatic while others present with one or more signs and symptoms of the classical triad of hemodynamic changes due to intracardiac obstruction, embolism and nonspecific constitutional symptoms. Echocardiography is highly sensitive and specific in detecting cardiac tumors. Other helpful investigations are chest X-rays, magnetic resonance imaging and computerized tomography scan. Surgical excision is the treatment of choice for primary cardiac tumors and is usually associated with a good prognosis. This review article will focus on the general features of benign cardiac tumors with an emphasis on cardiac myxomas and their molecular basis. PMID:24447924

Singhal, Pooja; Luk, Adriana; Rao, Vivek; Butany, Jagdish

2014-01-01

383

Medical devices and procedures in the hyperbaric chamber.  

PubMed

The aim of this paper is to present current controversies concerning the safety of medical devices and procedures under pressure in a hyperbaric chamber including: defibrillation in a multiplace chamber; implantable devices during hyperbaric oxygen treatment (HBOT) and the results of a recent European questionnaire on medical devices used inside hyperbaric chambers. Early electrical defibrillation is the only effective therapy for cardiac arrest caused by ventricular fibrillation or pulseless ventricular tachycardia. The procedure of defibrillation under hyperbaric conditions is inherently dangerous owing to the risk of fire, but it can be conducted safely if certain precautions are taken. Recently, new defibrillators have been introduced for hyperbaric medicine, which makes the procedure easier technically, but it must be noted that sparks and fire have been observed during defibrillation, even under normobaric conditions. Therefore, delivery of defibrillation shock in a hyperbaric environment must still be perceived as a hazardous procedure. Implantable devices are being seen with increasing frequency in patients referred for HBOT. These devices create a risk of malfunction when exposed to hyperbaric conditions. Some manufacturers support patients and medical practitioners with information on how their devices behave under increased pressure, but in some cases an individual risk-benefit analysis should be conducted on the patient and the specific implanted device, taking into consideration the patient's clinical condition, the indication for HBOT and the capability of the HBOT facility for monitoring and intervention in the chamber. The results of the recent survey on use of medical devices inside European hyperbaric chambers are also presented. A wide range of non-CE-certified equipment is used in European chambers. PMID:25596835

Kot, Jacek

2014-12-01

384

The mysterious pathways of cardiac myxomas: a review of histogenesis, pathogenesis and pathology.  

PubMed

Cardiac myxoma is the most common benign cardiac tumour, localized generally in the left atrium. The majority of cardiac myxomas occur sporadically, while a relatively small proportion of cases develop as a part of Carney complex syndrome. Currently, the histogenesis of myxoma is poorly understood; however, the mesenchymal and endothelial properties of myxoma cells suggest that a clearer understanding of tumour origins can be achieved through a detailed investigation of heart development and endocardial histogenesis. Growing evidence appears to indicate the reactivated expression in cardiac myxoma of genes encoding heart precursor markers, although the exact mechanisms have not yet been described. In this paper we review the most recent scientific literature concerning cardiac embryology and relate this to recent advances in our understanding of the histogenesis of cardiac myxoma. Moreover, given that much of the literature regarding myxoma is of single case reports, we review progress in our knowledge of the pathology and pathogenesis of this condition. PMID:25297937

Di Vito, Anna; Mignogna, Chiara; Donato, Giuseppe

2015-02-01

385

Facial nerve paralysis following pediatric cardiac surgery.  

PubMed

A newborn female diagnosed with transposition of the great vessels with restrictive ventricular septal defect presented left facial peripheral nerve paralysis following anatomical surgery correction (arterial switch) by cardiopulmonary bypass. We have not found any causal factor either in the anesthesia or postoperative period. The electromyogram presented signs of peripheral nerve impairment, and the cerebral echography and electroencephalogram were normal. The facial nerve paralysis was almost recovered seven weeks after surgery. This is the first pediatric patient reported with peripheral facial nerve paralysis after cardiac surgery. PMID:8869372

Alcaraz, A; Lopez-Herce, J; Castro, P; Bustinza, A; Moroto, C

1995-09-01

386

Regression of altitude-produced cardiac hypertrophy.  

NASA Technical Reports Server (NTRS)

The rate of regression of cardiac hypertrophy with time has been determined in adult male albino rats. The hypertrophy was induced by intermittent exposure to simulated high altitude. The percentage hypertrophy was much greater (46%) in the right ventricle than in the left (16%). The regression could be adequately fitted to a single exponential function with a half-time of 6.73 plus or minus 0.71 days (90% CI). There was no significant difference in the rates of regression for the two ventricles.

Sizemore, D. A.; Mcintyre, T. W.; Van Liere, E. J.; Wilson , M. F.

1973-01-01

387

Mitochondrial impairment contributes to cocaine-induced cardiac dysfunction: Prevention by the targeted antioxidant MitoQ  

Microsoft Academic Search

The goal of this study was to assess mitochondrial function and ROS production in an experimental model of cocaine-induced cardiac dysfunction. We hypothesized that cocaine abuse may lead to altered mitochondrial function that in turn may cause left ventricular dysfunction. Seven days of cocaine administration to rats led to an increased oxygen consumption detected in cardiac fibers, specifically through complex

Aurélia Vergeade; Paul Mulder; Cathy Vendeville-Dehaudt; François Estour; Dominique Fortin; Renée Ventura-Clapier; Christian Thuillez; Christelle Monteil

2010-01-01

388

Close view looking to left side of statue showing left ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Close view looking to left side of statue showing left hand, shield, and laurel wreath - U.S. Capitol, Statue of Freedom, Intersection of North, South, & East Capitol Streets & Capitol Mall, Washington, District of Columbia, DC

389

Regional Chamber of Commerce, Roanoke Regional Chamber of  

E-print Network

Chamber of Commerce, and NewVa Corridor Technology Center ­ is the name of the group that developed ­ America's 6-year-old celebration of books and reading ­ came to Patrick County in March. Poet Emily

Virginia Tech

390

Cardiac Risk Assessment  

MedlinePLUS

... helpful? Formal name: Cardiac Risk Assessment Related tests: Lipid Profile , VLDL Cholesterol , hs-CRP , Lp(a) Overview | ... on Coronary artery disease: Tests and diagnosis .) The lipid profile is the most important blood test for ...

391

Left ventricular non-compaction in a patient with myotonic dystrophy type 2.  

PubMed

Cardiac involvement is frequent in myotonic dystrophy type 2 (DM2) with dilated cardiomyopathy and severe arrhythmias having been reported. Left ventricular non-compaction is a cardiomyopathy often associated with neuromuscular disorders. We report the case of a 61-year-old man with DM2 treated for 5 years for a suspected dilated cardiomyopathy. Echocardiography showed left ventricular non-compaction typical pattern, with prominent apical trabeculations and intertrabecular spaces perfused from ventricular cavity. MRI confirmed the diagnosis. Physicians should be aware of the risk of severe cardiac complications in DM2 patients. Left ventricular non-compaction diagnosis is often overlooked. Neurological examination should be performed in all patients with left ventricular non-compaction. PMID:18395448

Wahbi, Karim; Meune, Christophe; Bassez, Guillaume; Laforêt, Pascal; Vignaux, Olivier; Marmursztejn, Julien; Bécane, Henri Marc; Eymard, Bruno; Duboc, Denis

2008-04-01

392

An altitude chamber rescue ensemble  

NASA Technical Reports Server (NTRS)

Altitude chamber tests accomplished with the astronaut crews in the spacecraft at a simulated altitude of above 200,000 ft requires that a rescue team be provided in the event of an accident in the spacecraft. The rescue crew is stationed in an airlock maintained at an altitude of 18,000 ft. A protective ensemble provides the rescue crew with life support capabilities, communications, and protection in the event of an emergency. In the event of an emergency, repressurization of the chamber is initiated; as the chamber descends, the airlock ascends and the two meet at 25,000 ft. This phase of the emergency repressurization takes less than 30 sec.

Lloyd, R. P.

1972-01-01

393

Autonomic cardiac innervation  

PubMed Central

Autonomic cardiac neurons have a common origin in the neural crest but undergo distinct developmental differentiation as they mature toward their adult phenotype. Progenitor cells respond to repulsive cues during migration, followed by differentiation cues from paracrine sources that promote neurochemistry and differentiation. When autonomic axons start to innervate cardiac tissue, neurotrophic factors from vascular tissue are essential for maintenance of neurons before they reach their targets, upon which target-derived trophic factors take over final maturation, synaptic strength and postnatal survival. Although target-derived neurotrophins have a central role to play in development, alternative sources of neurotrophins may also modulate innervation. Both developing and adult sympathetic neurons express proNGF, and adult parasympathetic cardiac ganglion neurons also synthesize and release NGF. The physiological function of these “non-classical” cardiac sources of neurotrophins remains to be determined, especially in relation to autocrine/paracrine sustenance during development.   Cardiac autonomic nerves are closely spatially associated in cardiac plexuses, ganglia and pacemaker regions and so are sensitive to release of neurotransmitter, neuropeptides and trophic factors from adjacent nerves. As such, in many cardiac pathologies, it is an imbalance within the two arms of the autonomic system that is critical for disease progression. Although this crosstalk between sympathetic and parasympathetic nerves has been well established for adult nerves, it is unclear whether a degree of paracrine regulation occurs across the autonomic limbs during development. Aberrant nerve remodeling is a common occurrence in many adult cardiovascular pathologies, and the mechanisms regulating outgrowth or denervation are disparate. However, autonomic neurons display considerable plasticity in this regard with neurotrophins and inflammatory cytokines having a central regulatory function, including in possible neurotransmitter changes. Certainly, neurotrophins and cytokines regulate transcriptional factors in adult autonomic neurons that have vital differentiation roles in development. Particularly for parasympathetic cardiac ganglion neurons, additional examinations of developmental regulatory mechanisms will potentially aid in understanding attenuated parasympathetic function in a number of conditions, including heart failure. PMID:23872607

Hasan, Wohaib

2013-01-01

394

Missed cardiac tamponade  

PubMed Central

Cardiac tamponade can have an insidious onset, becoming life threatening when an adequate cardiac output can no longer be maintained. This case provides an example of a presentation where all the classic signs were present but unfortunately they were missed, in this way providing good revision of what these signs are. It gives some anaesthetic and procedure based perspectives for this rare presentation. It is noteworthy for the speed at which symptoms and signs resolved after the tamponade was relieved. PMID:22679253

Thomson-Moore, Alexandra Louise

2011-01-01

395

INITIAL RESULTS OF CARDIAC IMAGING AT 7 T  

PubMed Central

This work reports preliminary results from the first human cardiac imaging at 7 T. Images were acquired using an 8-channel transmission line (TEM) array together with local B1 shimming. The TEM array consisted of anterior and posterior plates closely positioned to the subjects' thorax. The currents in the independent elements of these arrays were phased to promote constructive interference of the complex, short wavelength RF field over the entire heart. Anatomic and functional images were acquired within a single breath hold to reduce respiratory motion artifacts while a vector cardiogram (VCG) was employed to mitigate cardiac motion artifacts and gating. SAR exposure was modeled, monitored and was limited to FDA guidelines for the human torso in subject studies. Preliminary results including short-axis and four-chamber VCG-retrogated FLASH cines, as well as, short-axis TSE images demonstrate the feasibility of safe and accurate human cardiac imaging at 7 T. PMID:19097233

Snyder, CJ; DelaBarre, L; Metzger, GJ; van de Moortele, P-F; Akgun, C; Ugurbil, K; Vaughan, JT

2010-01-01

396

Cardiac Rehabilitation After Acute Myocardial Infarction Resuscitated From Cardiac Arrest  

PubMed Central

Objective To examine the safety and effectiveness of cardiac rehabilitation on patients resuscitated from cardiac arrest due to acute myocardial infarction. Methods The study included 23 subjects, including 8 with history of cardiac arrest and 15 without history of cardiac arrest. Both groups underwent initial graded exercise test (GXT) and subsequent cardiac rehabilitation for 6 weeks. After 6 weeks, both groups received follow-up GXT. Results Statistically significant (p<0.05) increase of VO2peak and maximal MVO2 but significant (p<0.05) decrease of submaximal MVO2 and resting heart rate were observed in both groups after 6 weeks of cardiac rehabilitation. An increasing trend of maximal heart rates was observed in both groups. However, the increase was not statistically significant (p>0.05). There was no statistically significant change of resting heart rate, maximal heart rate, maximal MVO2, or submaximal MVO2 in both groups after cardiac rehabilitation. Fatal cardiac complications, such as abnormal ECG, cardiac arrest, death or myocardial infarction, were not observed. All subjects finished the cardiac rehabilitation program. Conclusion Improvement was observed in the exercise capacity of patients after aerobic exercise throughout the cardiac rehabilitation program. Therefore, cardiac rehabilitation can be safely administered for high-risk patients with history of cardiac arrest. Similar improvement in exercise capacity can be expected in patients without cardiac arrest experience. PMID:25566479

Kim, Chul; Choi, Hee Eun; Kang, Seong Hoon

2014-01-01

397

Evaluation and management of left ventricular noncompaction cardiomyopathy.  

PubMed

Left ventricular (LV) noncompaction cardiomyopathy (LVNC) is a form of cardiomyopathy in which trabeculations fail to "compact" with the left ventricular endocardium during fetal cardiac development and is classically associated with subsequent impairment of LV function, significant mortality, ventricular dysrhythmias, and embolic phenomena. As awareness and medical imaging quality have improved, it is becoming easier to identify trabeculations that traverse the LV cavity and serve as a distinguishing feature of this disorder. Differentiating true noncompaction from mild increases in trabeculations requires prudent imaging and clinical correlation. This review seeks to discuss the potential methods of evaluating left ventricular trabeculations, the role of increased trabeculations in cardiovascular disease, and how their presence may affect clinical management. PMID:25399629

Stacey, R Brandon; Caine, Augustus J; Hundley, W Gregory

2015-02-01

398

Ultraviolet laser calibration of drift chambers  

E-print Network

We demonstrate the use of a focused ultraviolet laser as a track calibration source in drift chambers, and specifically in a small time projection chamber (TPC). Drift chambers such as TPCs reconstruct the trajectories of ...

Elliott, Grant (Grant Andrew)

2006-01-01

399

Arterial-Cardiac Interaction: The Concept and Implications  

PubMed Central

Vascular stiffening of the large arteries is a common feature of human aging. Increased aortic stiffness with age may contribute to pathological changes in the left ventricle and this can induce ventricular stiffening. Vascular-ventricular stiffening combined with abnormal arterial-cardiac interaction is considered an important pathophysiology of heart failure with a preserved ejection fraction. Here, I briefly review the concept and implications of arterial-cardiac interaction and this will pave the way to understanding and controlling heart failure with a preserved ejection fraction, which is more prevalent in the elderly. PMID:21860718

2011-01-01

400

Extra Terrestrial Environmental Chamber Design  

NASA Technical Reports Server (NTRS)

A vacuum chamber designed to simulate the dusty environment on the Moon or Mars has been built for Goddard Space Flight Center. The path from concept to delivery is reviewed, with lessons learned and pitfalls highlighted along the way.

Hughes, David W.

2008-01-01

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