Combined echo-apexcardiographic assessment of left ventricular function in cardiomyopathy.

Eleven patients with hypertrophic obstructive cardiomyopathy (HOCM) and 9 patients with congestive cardiomyopathy (COCM) were studied to determine the usefulness of mean normalized velocity of circumferential fiber shortening (VCFS), mean normalized velocity of circumferential fiber lengthening (VCFL) and left ventricular diastolic distensibility obtained noninvasively from combined recordings of simultaneously calibrated left apex cardiogram and M-mode echogram. Twenty-two normal subjects were similarly investigated and served as a control. In HOCM VCFS were increased (1.83 +/- 0.2 s-1 versus 1.22 +/- 0.1 s-1 for controls, p less than 0.02) and both VCFL and diastolic distensibility were decreased (VCFL: 0.50 +/- 0.1 s-1 versus 1.32 s-1 in controls, p less than 0.001; diastolic distensibility: 0.03 +/- 0.004 cm/mmHg-1 compared with 0.18 +/- 0.003 cm/mmHg-1 for controls, p less than 0.001). In COCM all investigated indexes were diminished (VCFS: 0.49 +/- 0.1 s-1 versus 1.22 +/- 0.1 s-1 for controls, p less than 0.001; VCFL: 0.70 +/- 0.1 s-1 versus 1.32 +/- 0.1 s-1 in controls, p less than 0.01 and diastolic distensibility: 0.05 +/- 0.003 cm/mmHg-1 compared with 0.18 +/- 0.003 cm/mmHg-1 for controls, p less than 0.01). The echo-apexcardiographic indexes were significantly correlated with many analogous invasive indexes. It is concluded that the value of both M-mode echocardiography and calibrated apex cardiography is enchanced by a combination of the two methods which opens the possibility of a fresh approach to the noninvasive study of cardiac performance in cardiomyopathy.