Effect of the calcium antagonist nisoldipine on electrophysiologic parameters in the human
Klein, H.H.; Nordbeck, H.; Kreuzer, H.
Zeitschrift für Kardiologie 72(3): 180-182
1983
ISSN/ISBN: 0300-5860 PMID: 6858297 Document Number: 218121
We investigated the influence of nisoldipine, a new calcium antagonist, on sinus node function, intracardiac conduction times, and the refractoriness of different compartments of the heart. Three catheters were placed in the right heart: a quadripolar one in the high right atrium, a bipolar one in the His position, and one in the apex of the right ventricle. Nisoldipine given i.v. in a dose of 1.5 microgram/kg body weight shortened the sinus node cycle length and the sinus node recovery time by 10%. The rate corrected sinus node recovery time, the sinoatrial conduction time, and the intracardiac conduction times remained unaffected. The effective refractory period of the right ventricle decreased slightly but significantly. The refractoriness of the other compartments did not change significantly. Systolic blood pressure decreased by 6%, whereas diastolic blood pressure remained constant. Nisoldipine thus exhibits no major effects on electrophysiological parameters in man. The increase in heart rate is regarded as a sympathetic reflex mechanism due to the decrease of systemic resistance.