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Dive into the research topics where Avinoam Shiran is active.

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Featured researches published by Avinoam Shiran.


Journal of the American College of Cardiology | 2009

Tricuspid regurgitation in mitral valve disease incidence, prognostic implications, mechanism, and management.

Avinoam Shiran; Alex Sagie

Tricuspid regurgitation (TR) in patients with mitral valve (MV) disease is associated with poor outcome and predicts poor survival, heart failure, and reduced functional capacity. It is common if left untreated after MV replacement mainly in rheumatic patients, but it is also common in patients with ischemic mitral regurgitation. It is less common, however, in those with degenerative mitral regurgitation. It might appear many years after surgery and might not resolve after correcting the MV lesion. Late TR might be caused by prosthetic valve dysfunction, left heart disease, right ventricular (RV) dysfunction and dilation, persistent pulmonary hypertension, chronic atrial fibrillation, or by organic (mainly rheumatic) tricuspid valve disease. Most commonly, late TR is functional and isolated, secondary to tricuspid annular dilation. Outcome of isolated tricuspid valve surgery is poor, because RV dysfunction has already occurred at that point in many patients. MV surgery or balloon valvotomy should be performed before RV dysfunction, severe TR, or advanced heart failure has occurred. Tricuspid annuloplasty with a ring should be performed at the initial MV surgery, and the tricuspid annulus diameter (>or=3.5 cm) is the best criterion for performing the annuloplasty. In this article we will review the current data available for understanding the prognostic implications, mechanism, and management of TR in patients with MV disease.


Cancer | 1993

Increased risk of cancer in patients with gaucher disease

Avinoam Shiran; Benjamin Brenner; Arie Laor; Ilana Tatarsky

Background. An increased incidence of cancer, especially hematopoietic in origin, has long been suspected but never established in patients with Gaucher disease.


The American Journal of Medicine | 1996

Anticardiolipin antibodies and acute myocardial infarction in non-systemic lupus erythmatosus patients: A controlled prospective study

Eli Zuckerman; Elias Toubi; Avinoam Shiran; Edmund Sabo; Zehava Shmuel; Theo Dov Golan; Edward G. Abinader; Daniel Yeshurun

PURPOSE To examine the prevalence of anticardiolipin antibodies (ACLA) in relatively young patients with acute myocardial infarction (MI) and their role in subsequent coronary and thromboembolic events in the post-MI period. PATIENTS AND METHODS In 124 relatively young survivors (aged 65 or younger) of acute MI, ACLA were measured in a controlled prospective study on admission and 3 months later. Myocardial reinfarction and thromboembolic events during a mean follow-up period of 19 +/- 3 months were diagnosed by standard tests. RESULTS Seventeen (14%) of the 124 patients were ACLA positive (either IgM or IgG) upon admission compared with 2 out of 76 (3%) of the control group matched for age and coronary risk factors (P < 0.01). The levels of ACLA remained unchanged in all but 1 patient 3 months later. During the follow-up period the rate of thromboembolic events and myocardial reinfarction was significantly higher in the ACLA-positive patients as compared with the ACLA-negative group: 41% versus 4% (P < 0.0001) and 35% versus 10% (P < 0.05), respectively. Using logistic regression, high titer of ACLA was found to be the only independent risk factor for subsequent thromboembolic events or myocardial reinfarction after acute MI. CONCLUSIONS High prevalence of ACLA was found in relatively young survivors of acute MI. The presence of ACLA is a marker for increased risk of subsequent myocardial reinfarction and thromboembolic events after acute MI.


Journal of The American Society of Echocardiography | 2012

Three-Dimensional Imaging of the Left Ventricular Outflow Tract: Impact on Aortic Valve Area Estimation by the Continuity Equation

Tamar Gaspar; Salim Adawi; Robert Sachner; Ihab Asmer; Majdi Ganaeem; Ronen Rubinshtein; Avinoam Shiran

BACKGROUND Measurement of left ventricular outflow tract (LVOT) area for estimation of aortic valve area (AVA) using two-dimensional (2D) transthoracic echocardiography (TTE) and the continuity equation assumes a round LVOT. The aim of this study was to compare measurements of LVOT area and AVA using 2D and three-dimensional (3D) TTE and cardiac computed tomographic angiography (CCTA) in an attempt to improve the accuracy of AVA estimation using TTE. METHODS Fifty patients were prospectively studied, 25 with aortic stenosis and 25 without aortic stenosis (group 1). LVOT area and AVA were estimated using 2D TTE, and LVOT area and diameters were measured using 256-slice CCTA and 3D TTE. AVA was also planimetered using CCTA in midsystole. LVOT area and AVA estimated by 2D TTE were correlated with measurements by 3D TTE and CCTA. Findings from group 1 were then validated in 38 additional patients with aortic stenosis (group 2). RESULTS LVOTs were oval in 96% of the patients in group 1, with a mean eccentricity index (diameter 2/diameter 1) of 1.26 ± 0.09 by CCTA. Compared with CCTA, 2D TTE systematically underestimated LVOT area (and therefore AVA) by 17 ± 16%. The correlation between CCTA and 3D TTE LVOT area was only moderate (r = 0.63), because of inadequate 3D transthoracic echocardiographic image quality. Mean AVA was 0.92 ± 0.44 cm(2) by 2D TTE and 1.14 ± 0.68 cm(2) by CCTA (P = .0015). After correcting AVA on 2D TTE by a factor of 1.17 (accounting for LVOT area ovality), there was no difference between 2D TTE and CCTA (0.06 ± 26 cm(2), P = .20, r = 0.86). In group 2, 2D TTE underestimated LVOT area and AVA by 16 ± 11%, similar to group 1, and AVA by TTE was 0.75 ± 0.14 cm(2) compared with 0.88 ± 0.21 cm(2) by CCTA (P < .0001). When the correction factor was applied to the group 2 results, the corrected AVA by 2D TTE (×1.17) was 0.87 ± 0.17 cm(2), similar to AVA by CCTA (P = .70). CONCLUSIONS Three-dimensional imaging revealed oval LVOTs in most patients, resulting in underestimation of LVOT area and AVA on 2D TTE by 17%. This accounted for the difference in AVA between 2D TTE and CCTA. Current 3D TTE is inadequate to accurately measure LVOT area.


Coronary Artery Disease | 1999

Electromechanical characterization of myocardial hibernation in a pig model.

Shmuel Fuchs; Ran Kornowski; Avinoam Shiran; Anthony Pierre; Samer Ellahham; Martin B. Leon

BACKGROUND This study attempted to assess in-vivo electromechanical changes following gradual coronary artery occlusion in a pig ameroid constrictor model using a novel three-dimensional left ventricular mapping system. METHODS AND RESULTS We measured unipolar and bipolar voltage potentials and local endocardial shortening in the ischemic lateral and non-ischemic anterior zones in animals at rest (n = 9) 5 weeks after the implantation of ameroid constrictors around the left circumflex artery. Echocardiography was used to assess regional contractility (percentage myocardial thickening), and an echo-contrast perfusion study was performed using acoustic densitometry methods. The ischemic lateral zone showed reduced myocardial perfusion at rest (peak intensity; 3.4 +/- 1.7 versus 20.7 +/- 14.8, P = 0.005), impaired mechanical function (percentage wall thickening 22 +/- 19% versus 40 +/- 11%, P = 0.03; local endocardial shortening 2.9 +/- 5.5% versus 11.7 +/- 2.1%, P = 0.002), and preserved electrical activity (unipolar voltage 12.4 +/- 4.7 versus 14.4 +/- 1.9 mV, P = 0.25; bipolar voltage 4.1 +/- 1.1 versus 3.8 +/- 1.5 mV, P = 0.62), compared with the anterior region. CONCLUSIONS Gradual coronary artery occlusion resulting in regional reduced perfusion and function at rest (i.e. hibernating myocardium) is characterized by preserved electrical activity. An electromechanical left ventricular mapping procedure such as the one described here may be of diagnostic value for identifying the hibernating myocardium.


European Journal of Echocardiography | 2008

Accuracy and reproducibility of left ventricular outflow tract diameter measurement using transthoracic when compared with transesophageal echocardiography in systole and diastole

Avinoam Shiran; Salim Adawi; Majdi Ganaeem; Ehab Asmer

AIMS Accurate measurement of left ventricular outflow tract diameter (LVOTd) is essential for reliable estimation of aortic valve area (AVA) using the continuity equation. Transesophageal echocardiography (TEE) can accurately delineate the LVOT. The aim of this study was to assess the accuracy and reproducibility of LVOTd measurement using transthoracic echocardiography (TTE) with harmonic imaging when compared with TEE, in both systole and diastole. METHODS AND RESULTS We prospectively studied 50 patients [20 with aortic stenosis (AS) and 30 without AS]. LVOTd was measured offline in a blinded fashion in both systole and diastole by two experienced observers using TTE in the parasternal long axis view and TEE in the mid-oesophageal aortic view ( approximately 130 degrees ). There was strong correlation between TTE and TEE (r=0.91). LVOTd was slightly smaller by TTE when compared with TEE (2.11+/-0.21 vs. 2.16+/-0.22 cm, mean difference -0.05+/-0.09 cm, P=0.0003). Compared with TEE, 95% (2SD) of LVOTd measurements by TTE were within +0.14 and -0.24 cm. Inter- and intra-observer variability for LVOTd was 4.8+/-4.1 and 2.8+/-1.9% for TTE and 4.2+/-3.1 and 2.5+/-1.6% for TEE (P=0.4 and 0.6). In patients with AS, estimated AVA was 0.93+/-0.22 cm(2) using TTE and 0.96+/-0.24 cm(2) using TEE, P=0.08. Diastolic LVOTd by TEE was slightly smaller compared with systolic LVOTd by TEE (-0.03+/-0.07 cm, P=0.0005), and there was strong correlation between the two (r=0.95). CONCLUSION We present the data regarding accuracy and reproducibility of LVOTd measurements by TTE when compared with TEE. LVOTd measurements at end-diastole may be helpful when systolic images are suboptimal.


European Journal of Echocardiography | 2012

Right ventricular outflow tract systolic excursion: a novel echocardiographic parameter of right ventricular function

Ihab Asmer; Salim Adawi; Majdi Ganaeem; Jeryes Shehadeh; Avinoam Shiran

AIMS Right ventricular (RV) function has important prognostic and therapeutic implications. Assessment of RV function using echocardiography is challenging. The aim of this study was to evaluate a new parameter of RV function, right ventricular outflow tract systolic excursion (RVOT_SE). METHODS AND RESULTS RVOT_SE was measured using M-Mode echocardiography from the parasternal short-axis view at the level of the aortic valve, and was defined as the systolic excursion of the RVOT anterior wall. RVOT_SE was measured in 50 patients (age 64 ± 18 years, 28 males) with normal RV function [RV fractional area change (FAC) ≥35% and tricuspid annular plane systolic excursion (TAPSE) ≥1.6 cm] and 40 patients (age 68 ± 12 years, 35 males) with reduced RV function (RV FAC <35% and TAPSE <1.6 cm). R.V FAC was 46 ± 7% in the normal RV group and 22 ± 5% in the reduced RV group (P < 0.0001). TAPSE was 2.2 ± 0.4 cm in the normal RV group and 1.0 ± 0.2 cm in the reduced RV group (P < 0.0001). RVOT_SE was 9.6 ± 1.5 mm in the normal RV group and 1.7 ± 1.1 mm in the reduced RV group (P < 0.0001). RVOT_SE <6 mm identified patients with reduced RV function with 100% sensitivity and 100% specificity. Survival at 1 year was 63% in patients with RVOT_SE <6 mm and 84% in patients with RVOT_SE ≥6 mm, P = 0.004. CONCLUSION RVOT_SE is a novel, simple, and promising parameter for assessing RV function, and it is associated with poor survival.


The Cardiology | 1997

Determinants of improvement in exercise capacity in patients undergoing cardiac rehabilitation.

Avinoam Shiran; Sarah Kornfeld; Suzan Zur; Arie Laor; Yafa Karelitz; Arie Militianu; Amnon Merdler; Basil S. Lewis

In order to identify patients who benefit most from a cardiac rehabilitation program, we studied retrospectively all patients who completed a 3-month comprehensive cardiac rehabilitation program during a 2-year period. Questionnaires regarding physical exercise habits were sent to 122 patients and returned by 117 (96%) of them (53 post-acute myocardial infarction, 50 post-coronary artery bypass surgery, 14 post-infarction and surgery, 2 post-angioplasty). Exercise capacity (subset of 66 patients) improved by 19% after rehabilitation (7.8 +/- 3.1 to 9.3 +/- 2.7 METs, p < 0.0001). Univariate and multivariate analysis identified initial exercise capacity as the only independent variable predicting improvement in exercise performance (inverse relationship) (r2 = 0.24, p < 0.0001). The improvement was not related to age, sex, left ventricular function or time from cardiac event to rehabilitation. Patients recovering from both infarction and coronary artery bypass surgery showed a greater improvement (delta exercise capacity 2.8 +/- 1.4 METs) than patients after myocardial infarction alone (delta exercise capacity 0.8 +/- 2 METs, p < 0.02). Improvement was sustained for up to 2 years after completion of the program.


Circulation | 2008

A Perfectly Functioning Magovern-Cromie Sutureless Prosthetic Aortic Valve 42 Years After Implantation

Amnon Y. Zlotnick; Avinoam Shiran; Basil S. Lewis; Dan Aravot

A 65-year–old man was admitted with recurrent pulmonary edema. At the age of 23, 42 years before his admission, he had had an aortic valve replacement with a “ball-and-cage” valve for severe aortic stenosis. He had suffered a postoperative hemorrhagic stroke with right hemiparesis but had been doing well on warfarin for 42 years. Echocardiography demonstrated a perfectly functioning prosthetic aortic valve with peak transvalvular gradient of 23 mm Hg and mean gradient of 13 mm Hg with no aortic regurgitation (Figure 1, Movie I). There was also severe rheumatic mitral valve stenosis. Coronary angiography showed insignificant coronary disease, and on fluoroscopy an unusual …


American Journal of Cardiology | 1998

Importance of diabetes mellitus and systemic hypertension rather than completeness of revascularization in determining long-term outcome after coronary balloon angioplasty (the LDCMC registry) ☆

David A. Halon; Amnon Merdler; Moshe Y. Flugelman; Galia Shifroni; Nader Khader; Avinoam Shiran; Johnny Shahla; Basil S. Lewis

The study examined the 10-year outcome in a cohort of 227 unselected, consecutive patients (age 58+/-10 years) undergoing coronary balloon angioplasty between 1984 and 1986 and followed in a single cardiac center (Lady Davis Carmel Medical Center registry). In particular, we sought to identify the relative importance of the systemic risk factors diabetes and hypertension and the extent of coronary disease as opposed to procedure-related technical variables, the immediate success of the procedure, or completeness of revascularization. By life-table analysis (99% follow-up), 94% of the patients were alive at 5 years, and 77% at 10 years after angioplasty. Ten-year survival was reduced in patients with diabetes mellitus (59% vs 83%, p = 0.0008), in patients with previous myocardial infarction (68% vs 85%, p = 0.01), in patients with ejection fraction <50% (55% vs 82%, p = 0.005), and in patients with 3-vessel disease (58% vs 84% and 86% for 1- and 2-vessel disease, respectively, p = 0.04). Diabetes mellitus was the major independent predictor of poor survival (adjusted odds ratio 3.1, 95% confidence interval 1.55 to 6.19, p = 0.001). Survival at 10 years was identical in 199 patients in whom angioplasty was complete and in 25 in whom the balloon catheter did not cross the lesion, although bypass surgery was more frequent in the latter group (45% vs 21%, p = 0.001). Incomplete revascularization did not predict poor survival (72% vs 79% with complete angioplasty, p = NS). Event-free survival at 10 years for the whole group was 29%, and 49% of patients survived with no event other than a single repeat angioplasty procedure. Multivessel disease, hypertension, and diabetes mellitus were independent predictors of decreased event-free survival, but incomplete revascularization was not. Thus, long-term outcome after coronary balloon angioplasty was related to diabetes mellitus, systemic hypertension, and extent of coronary disease, but not to the immediate success of the procedure or completeness of revascularization.

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Basil S. Lewis

Technion – Israel Institute of Technology

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David A. Halon

Technion – Israel Institute of Technology

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Moshe Y. Flugelman

Rappaport Faculty of Medicine

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Ronen Jaffe

Technion – Israel Institute of Technology

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Salim Adawi

Rappaport Faculty of Medicine

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Amnon Merdler

Technion – Israel Institute of Technology

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Basheer Karkabi

Technion – Israel Institute of Technology

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Ronen Rubinshtein

Technion – Israel Institute of Technology

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Nader Khader

Technion – Israel Institute of Technology

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Tamar Gaspar

Technion – Israel Institute of Technology

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