title: The cardiac electrophysiological effects of nifedipine.
abstract: A study was carried out on the electrophysiological effects of a sublingually administered antianginal drug: nifedipine (20 mg). The results show a significant shortening of sinus cycle length from 925 +/- 249 msec to 810 +/- 245 msec, (p less than 0.005) and the disappearance of some interpolation and echo zones. There are no significant effects on the other evaluated parameters of sino-atrial and AV-node function. In one case, during atrial pacing, a second-degree, Wenckebach type, A-V block was present only before nifedipine. The following conclusions were reached: 1. nifedipine has no significant electrophysiological effect on the human heart; 2. the electrophysiological effects observed are probably indirect and related to the vasodilating effect of the drug; 3. the absence of direct cardiac electrophysiological actions may be useful in patients suffering from coronary artery disease and presenting disturbances in the formation and/or conduction of the cardiac impulse.
mesh_terms: D000328:Adult; D000368:Aged; D004562:Electrocardiography; D004594:Electrophysiology; D005260:Female; D006321:Heart / Q000187:drug effects*; D006329:Heart Conduction System / Q000187:drug effects; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D009543:Nifedipine / Q000494:pharmacology*; D011725:Pyridines / Q000494:pharmacology*; D012849:Sinoatrial Node / Q000187:drug effects
chemical_list: D011725:Pyridines; D009543:Nifedipine