The systemic and coronary haemodynamic effects of felodipine in patients with coronary heart disease.

The cardiovascular effects of felodipine, a new arteriolar vasodilator, were studied in 22 patients with coronary heart disease. There were significant falls in blood pressure and systemic vascular resistance of 16 and 38% respectively (P = 0.001), thus affecting after-load. Cardiac index and stroke index increased by 35 and 12% respectively. There was reflex tachycardia--from 75 +/- 3 to 85 +/- 3 b.p.m. (P = 0.005). Coronary sinus blood flow increased from 134 +/- 9 to 191 +/- 17 ml/min (P less than 0.005) and myocardial arterio-venous oxygen difference narrowed from 12.1 +/- 0.5 to 9.0 +/- 0.4 vols% (P less than 0.001) indicating less oxygen usage. With the heart rate held constant by atrial pacing, cardiac index and stroke index increased by 30 and 26% (P less than 0.001), whilst systolic blood pressure and systemic vascular resistance fell by 20 and 29% (P less than 0.001). This would suggest that the improved haemodynamics were largely secondary to after-load reduction.