Noninvasive study of early diastole in mitral stenosis

Diastolic amplitude time index: a new apexcardiographic index of left ventricular diastolic function in human beings

Left ventricular apexcardiography was performed in 260 normal subjects and 37 patients undergoing diagnostic cardiac catheterization: 13 without left heart disease (group 1), 18 with congestive cardiomyopathy (group 2) and 6 with idiopathic hypertrophic subaortic stenosis (group 3). In the patients undergoing catheterization the apexcardiogram was recorded simultaneously with left ventricular pressure (tipmanometer) and its first derivative (dP/dt). The following variables were measured in the apex tracing: (1) the time from the onset of the aortic component of the second heart sound (A2) in the phonocardiogram to the nadir of the apexcardiogram, termed total apexcardiographic relaxation time (TART), (2) the time from A2 to the onset of the systolic upstroke (C point) of the apexcardiogram (A2-C), and (3) the ratio of the A wave (A) to the total diastolic amplitude (D) of the apexcardiogram (A/D). The diastolic amplitude time index (DATI) was calculated according to the following formula DATI = (square root A2-C/TART)/(A/D). In the normal subjects the diastolic amplitude time index was 0.82 +/- 0.26 (mean +/- standard deviation). In group 1 this index was within normal limits; in groups 2 and 3 it was decreased (0.23 +/- 0.07 and 0.18 +/- 0.05, respectively). This index showed excellent correlation with specific compliance of the left ventricle (r = +0.90) and close correlations with the maximal rate of decrease of left ventricular pressure (minimal dP/dt) (r = +0.79) as well as the velocity of lengthening of the contractile elements at minimal dP/dt (r = +0.77); less close correlation was obtained with the end-diastolic volume compliance (r = +0.67). These results demonstrate that the diastolic amplitude time index reflects interpatient differences in both relaxation ability and diastolic distensibility of the human left ventricle. Thus, this measurement provides an important new method for noninvasive evaluation of the overall function of the left ventricle during diastole.

Double diastolic murmur in mitral stenosis with atrial fibrillation and complete heart block

A double diastolic murmur was heard in a patient with mitral stenosis, atrial fibrillation, and complete heart block. Echo-phonocardiographic examination showed two separate opening and closing movements of the mitral valve in the same long diastole. A clear time relation was observed between the valve closing movements and the separate diastolic murmurs, giving support to the theory that the backward motion of the mitral valve against the forward blood flow through the valve is responsible for the production of these murmurs.