Mechanics of Left Ventricular Contraction in Chronic Severe Mitral Regurgitation

Abstract

SUMMARYThe mechanics of left ventricular contraction were studied during diagnostic cardiac catheterization using high-speed cineangiography in 11 patients with severe chronic mitral regurgitation. Compared with a group of previously studied normal subjects, most of the patients with mitral regurgitation demonstrated a reduced velocity of shortening (Vf) we utilized quantitative cineangiographic and hemodynamic technics to define left ventricular performance and to estimate myocardial contractility. MethodsEleven patients with clinical and hemodynamic evidence of severe mitral regurgitation comprised the study group. Their ages ranged from 7 to 62 years (mean 38 years). None of the patients had diastolic arterial hypertension ( > 90 mm Hg); four had systolic arterial pressures greater than 140 mm Hg at rest. Two of these (D.M. and F.W.) also had trivial aortic regurgitation. Nine were in New York Heart Association functional class III, and two were in class II.2 One patient (T.S.) was believed to have sustained rupture of mitral valve chordae tendineae 6 years prior to study. Two patients (M.R. and M.M.) had congenital mitral regurgitation, and the remaining eight patients had rheumatic heart disease. Two patients had a history suggestive of ischemic chest pain; in one patient (J.M.) coronary arteriograms were within normal limits. In the other patient (F.W.) coronary arteriograms were not performed. However, localized abnormalities of left ventricular wall motion were not observed in any of the left ventriculograms.

Time variation of mitral regurgitant flow in patients with dilated cardiomyopathy.

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Hemodynamic predictors of outcome in patients undergoing valve replacement.

“…Angiograms and pressure tracings from all 74 patients who underwent single, first valve replacement from June 1, 1980, to September 1, 1985, at Temple University were evaluated for study. Patients were excluded from the study if (1) there was obstructive coronary disease reducing vessel luminal diameter by 50% or more (15 patients), (2) angiographic images did not permit adequate edge detection for the determination of ventricular volumes and/or thickness (12 patients), or (3) there were not two consecutive sinus beats or, if the patient had atrial fibrillation, there were not two consecutive nonectopic beats during angiography. Premature beats and postpremature beats were excluded from evaluation (eight patients).…”

Valvular-ventricular interaction: importance of the mitral apparatus in canine left ventricular systolic performance.

“…which in turn reduces left ventricular shortening. 1 14 Therefore the mechanical consequences of mitral valve excision cannot be directly assessed in patients with chronic mitral regurgitation when conventional loaddependent methods are used to assess left ventricular function.…”