Left ventricular end-diastolic pressure-volume relationships in hypertrophic cardiomyopathy. Changes induced by verapamil.

In 16 patients with hypertrophic cardiomyopathy, an acute response of the left ventricular end-diastolic pressure and volume index to intravenously administered verapamil was assessed. Verapamil decreased the left ventricular end-diastolic pressure from 20 +/- 6 to 17 +/- 5 mm Hg(p less than 0.001) and increased the end-diastolic volume index from 82 +/- 22 to 91 +/- 23 ml/sqm (p less than 0.01). In 13 (81 percent) of 16 patients, an improvement of end-diastolic pressure-volume relationships occurred. In hypertrophic cardiomyopathy, intravenous verapamil exerts a beneficial effect on left ventricular filling conditions, producing an augmentation of filling volume at a lower filling pressure.