Effects of a slow-release nifedipine on 24-hour ambulatory blood pressure and ischemic changes on 24-hour ambulatory electrocardiogram in patients with severe coronary artery disease

Calcium antagonists have long been used as first-line drugs for hypertensio n and angina, However, deleterious effects have also been reported in patie nts treated with calcium antagonists. Thus, we evaluated the effect of a sl ow-release twice-daily formulation of nifedipine in 10 patients with severe coronary artery disease. Twenty-four-hour ambulatory electrocardiography ( AECG) and blood pressure monitoring (ABPM) were performed simultaneously to detect any association between ischemic episodes on the ECG and changes in blood pressure (BP) and heart rate with and without nifedipine. Increased oxygen demand due to an increased systolic BP and heart rate was associated with ischemic episodes without nifedipine, while those with nifedipine wer e accompanied by a fall in diastolic BP and a rapid increase in heart rate. Th is slow-release twice-daily formulation of nifedipine may induce myocar dial ischemia through a heart-rate increase and a decrease in coronary bloo d flow due to lower diastolic BP in patients with severe coronary artery di sease. A once-daily formulation of nifedipine might be of great value for s uch patients. Copyright (C) 2000 S. Karger AG,Basel.