[Anti-anginal effects of calcium antagonists and intra-cardiac hemodynamics].

The intracardiac hemodynamics was studied in 33 patients with exertional angina pectoris undergoing an acute drug test with verapamil (n-15) and nifedipine (n-18) by using radionuclide ventriculography both at rest and during exercise. All the patients were divided into 2 groups by the increase in exercise duration with the two drugs: 1) those who exhibited a marked antianginal effect and 2) those without it. At rest, the calcium antagonists enhanced ejection fraction in the two groups. Exercise ejection fraction also increased, but in a subgroup of patients who displayed no higher exercise tolerance with verapamil. Verapamil and nifedipine in Group 1 patients resulted in lower left ventricular end diastolic volume. It is suggested that the antianginal effect of calcium antagonists is to a certain degree associated with decreased afterload, as manifested by diminished left ventricular end systolic volume.