This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Kurnik, P. B. Articles by Ludbrook, P. A. Search for Related Content PubMed PubMed Citation Articles by Kurnik, P. B. Articles by Ludbrook, P. A.

Circulation, Vol 69, 963-972, Copyright © 1984 by American Heart Association

ARTICLES

The dependence of the cardiac effects of nifedipine on the responses of the peripheral vascular system

PB Kurnik, AJ Tiefenbrunn and PA Ludbrook

To elucidate the mechanisms of reduction of left ventricular end- diastolic pressure by nifedipine in certain individuals, we evaluated cardiac and peripheral hemodynamic responses in 32 patients after they were randomly assigned to nifedipine (20 mg sublingually) or to placebo treatment. Forearm plethysmography was performed during cardiac catheterization with micromanometers. No hemodynamic parameters were changed after placebo. Left ventricular end-diastolic pressure declined by 14% (p less than .02) after nifedipine in patients with impaired left ventricular function, but was unchanged in those with normal function; indexes of peripheral venous hemodynamics (forearm venous tone, forearm volume change) were not affected. In those patients with abnormal left ventricular function, forearm vascular resistance decreased 36% and forearm blood flow increased 31% (p less than .0005 for both), while neither changed in those with normal function. Cardiac output increased by 10% in patients with impaired left ventricular function but was unchanged in the remainder, while calculated total systemic resistance fell by 24% in those with abnormal left ventricular function (p less than .002 for both). Thus, reduction of left ventricular preload by nifedipine is not attributable to venous pooling, but rather this beneficial effect appears to be attributable to improved left ventricular systolic function in response to afterload reduction, particularly in patients with impaired left ventricular function.

This article has been cited by other articles:

				R. M. MacMillan, Se Do Cha, and V. Maranhao Acute Hemodynamic Effects of Nifedipine During Supine Exercise in Patients with Prior Myocardial Infarction Angiology, March 1, 1986; 37(3): 168 - 174. [Abstract] [PDF]