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A Benchimol

Publications and source records attributed to A Benchimol.

247 records · Page 14Linked to original sources
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Simultaneous left ventricular echocardiography and aortic blood velocity during rapid right ventricular pacing in man.

Left ventricular echocardiograms and phasic instantaneous Doppler aortic blood velocities were simultaneously recorded during short paroxysms of rapid right ventricular pacing in 20 conscious subjects. Right ventricular pacing at rates of 100, 120, 140, 160 and 180/min produced stepwise reductions of mean estimates for diastolic (D) and systolic (S) left ventricular internal dimensions (LVID) along with a diminution of aortic blood velocity. Mean (X +/- 1 standard deviation) per cent decline of LVID-D, LVID-S and peak aortic blood velocities for the study group ranged from 8.9 +/- 6.1, 8.5 +/- 5.7 and 13.7 +/- 7.7 at 100 beats/min to 29.3 +/- 10.6, 25.2 +/- 10.5 and 55.2 +/- 13.1 at 180 beats/min, respectively. When LVID-D, LVID-S, and aortic blood velocity X % reductions were plotted for all heart rates there was a high degree of positive correlation (r = 0.99). Two types of abnormal septal motion were observed during rapid pacing: Type I--paradoxical septal motion at all pacing rates (n = 7, 6/7 with left coronary artery disease); Type II--hypokinetic septal motion at lower pacing rates with flat or paradoxical motion at rates greater than 140/min (n = 13, 10/13 with normal coronary arteries). It is concluded that short episodes of rapid right ventricular pacing result in reduced LVID and abnormal septal motion with the latter possibly related to septal ischemia. Such study provides insight into the untoward influence of rapid ventricular rhythms on cardiac performance.

Adult↗
PubMedDate not supplied

Effects of atrial arrhythmias on aortocoronary bypass graft blood velocity in man.

Utilizing a Doppler ultrasonic flowmeter catheter, phasic instantaneous aortocoronary saphenous vein bypass blood velocity was recorded during various atrial arrhythmias in 17 patients. Atrial premature beats, supraventricular tachycardia and atrial fibrillation reduced peak bypass graft blood velocity in relation to the heart rate and diastolic cycle length. Such changes were more evident during the systolic fraction of bypass blood flow. In a single subject, systolic blood velocity alternans was observed during the course of atrial tachycardia. It is concluded that such study provides insight into the dynamics of bypass graft blood flow velocity during atrial arrhythmias.

Adult↗
PubMedDate not supplied

Carotid blood velocity during cough studies in man.

Utilizing a Doppler ultrasonic flowmeter catheter, right carotid artery blood velocity was measured during 91 coughing episodes in 16 patients. Such coughing reduced carotid blood velocity by 40 +/- 22% (control = 34 +/- 8 cm per second, cough = 20 +/- 9 cm per second, p less than 0.001). There was an insignificant low degree of corrleation between the level of simultaneously recorded mean right pressure and the percent decline of peak carotid blood velocity, suggesting that impaired venous return was not the only factor responsible for the observed changes. It is concluded that (1)coughing diminishes phasic carotid blood velocity and (2)reduced cerebral perfusion may play a role in the pathogenesis of cough syncope.

Adult↗
PubMedDate not supplied

Aneurysms of an aorto-coronary artery saphenous vein bypass graft--a case report.

A 62 year old man with severe angina pectoris underwent aoroto-coronary saphenous vein graft implantation. After a four month asymptomatic period the patient underwent aorto-coronary graft angiography. Left anterior descending graft opacification demonstrated multiple venous aneurysmal dilations. The clinical significance of this finding is currently unknown but such saphenous vein disease warrants further investigation. Saphenous vein grafts have been utilized to replace or bypass obstructed and diseased peripheral arteries such as those of the carotid and femoral-popliteal vascular systesm. In 1967 Favaloro introduced the saphenous vein as a means for bypassing local obstructions in diseased coronary arteries of human subjects. Since the advent of the aorto-coronary saphenous vein bypass graft procedure several studies have reported pathologic alterations of these grafts at post-mortem examination or at the time of re-operation. Other investigators have also noted changes in these venous grafts when they have been implanted in peripheral vessels. We report here a patient with aneruysmal dilations of an aorto-coronary artery saphenous vein bypass graft. Furthermore, possible mechanisms which might produce such venous aneurysms and the clinical significance of such an entity are discussed.

Aneurysm↗
PubMedDate not supplied

The echocardiographic diagnosis of calcified mitral annulus.

Echocardiograms were recorded in six patients with calcification of the mitral annulus. Echocardiographic sweep from the aorta to the left ventricular cavity revealed dense echoes, representing annulus calcification, posterior to the mitral valve. Characteristic calcium deposits in the region of the mitral annulus were detected on the chest roentgenogram of only a single subject. Cardiac fluoroscopy fluoroscopy demonstrated calcified mitral annulus in all patients. In one patient, coexisting calcified mitral annulus and proven pericardial effusion were diagnosed echocardiographically. It is concluded that the echocardiogram represents a useful noninvasive technic for the diagnosis of calcified mitral annulus.

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