Atropine‐Induced Multilevel Block in Acute Inferior Myocardial Infarction A Possible Indication for Prophylactic Pacing
- 1 September 1981
- journal article
- Published by Wiley in Pacing and Clinical Electrophysiology
- Vol. 4 (5), 528-536
- https://doi.org/10.1111/j.1540-8159.1981.tb06224.x
Abstract
The degree of A-V block increased after intravenous administration of atropine in 10 nondigitalized patients with acute inferior myocardial infarction who had narrow QRS complexes during periods of 1:1 A-V conduction. Short episodes of 3:1, 4:1 and 5:1 A-V block were seen to emerge: (a) in 6 patients, directly from Wenckebach periods; (b) in 3 patients, from alternating Wenckebach periods; and (c) in 1 patient, from a 3:2 Wenckebach period which led to a short-lived alternating Wenckebach period. Apparently, the predominance of the chronotropic effects on the sinus node over the dromotropic effects on the A-V node led to a tachycardia-dependent (more ischemic than vagal) process, exposing or producing multi- (two, three or four) level block involving the A-V node (and perhaps the His bundle). Subsequently, therapeutic pacing was instituted in 9/10 patients because they developed spontaneous symptomatic advanced A-V block. Therefore, it is possible that the early effects of atropine identified a narrowly-defined subset of patients in whom prophylactic pacing may be indicated. However, more studies are necessary to corroborate these assumptions.Keywords
This publication has 30 references indexed in Scilit:
- The effect of atropine on cardiac arrhythmias and conduction. Part 1American Heart Journal, 1980
- Use of atropine in patients with acute myocardial infarction and sinus bradycardia.Circulation, 1975
- The Pathophysiology of Tachycardia-dependent Paroxysmal Atrioventricular Block After Acute Myocardial IschemiaCirculation, 1974
- Atropine-lnduced cardioacceleration and myocardial blood flow in subjects with and without coronary artery diseaseThe American Journal of Cardiology, 1974
- Ventricular Fibrillation and Tachycardia after Intravenous Atropine for Treatment of BradycardiasThe New England Journal of Medicine, 1972
- Autonomic Disturbance at Onset of Acute Myocardial InfarctionBMJ, 1972
- Bradyarrhythmias in Acute Myocardial InfarctionCirculation, 1972
- Artificial Cardiac PacemakersThe New England Journal of Medicine, 1970
- The significance of atrial rate in patients with atrioventricular conduction abnormalities complicating acute myocardial infarctionThe American Journal of Cardiology, 1969
- Treatment of bradycardia and hypotension syndrome in patients with acute myocardial infarctionAmerican Heart Journal, 1968