Hemodynamic Effects of Diltiazem and Nitrendipine Assessed by Noninvasive Methods in Patients with Congestive Heart Failure

Abstract

In a placebo-controlled randomized double-blind cross-over study 16 patients with congestive heart failure (NYHA stage II; 12 male and 4 female; age 60.2 ± 9.8 years; body weight 77.8 ± 13.9 kg; X ± SD) received single oral doses of 90 and 180 mg diltiazem sustained release (s.r.) as well as 20 and 40 mg nitrendipine. Systolic time intervals, impedance cardiography, venous occlusion plethysmography, heart rate and blood pressure were measured 3, 6 and 12 h after administration of the drug. In impedance cardiography both dosages of diltiazem s.r. led to a significant increase in stroke volume and the heather index compared with the placebo values. Nitrendipine, on the other hand, only slightly increased these parameters. Cardiac output was not influenced by any of the kinds of treatment. While heart rate was significantly reduced after ingestion of 90 and 180 mg diltiazem s.r., it was accelerated under the influence of nitrendipine. Both calcium channel blockers significantly reduced diastolic blood pressure, but only 180 mg diltiazem s.r. exerted a marked antihypertensive effect on systolic blood pressure. In mechanocardiography the preejection period was shortened after administration of diltiazem and nitrendipine, although this effect was only significant for 180 mg diltiazem s.r. The PEP/LVET ratio was slightly reduced under the four different kinds of treatment; the parameters measured by venous occlusion plethysmography remained unchanged. From the results of the present study it can be concluded that over a 12-hour period of observation 90 and 180 mg diltiazem s.r. exert a more favorable effect on cardiac performance than 20 and 40 mg nitrendipine. By increasing stroke volume and - at the same time - reducing heart rate, diltiazem s.r. enables the left ventricle to work on a more economic base than nitrendipine does.

Twenty-Four-Hour Hemodynamic Effects of Two Different Dihydropyridine Derivatives Assessed by Noninvasive Methods in Patients with Congestive Heart Failure

“…In the present study, PEP was not heart rate corrected. Furthermore, STIs should always be interpreted in the light of the various determinants of ventricular function, i.e., heart rate, contractility, preload, and afterload [14], Stroke volume (AV), cardiac output (CO) and Heather index (HI) were obtained by impedance cardiography, a standard technique [14][15][16][17], Venous occlusion plethysmography was performed with the patient lying in supine position with his leg placed above heart level. The circulation sensor was attached to the lower leg (around the widest girth of the calf), and the pressure cuff was fixed at the thigh, as close to the knee joint as possible.…”