Electrophysiological, Biochemical and Pharmacological Aspects of Reentrant Ventricular Arrhythmias in the Late Myocardial Infarction Period

Abstract

Myocardial infarction represents a highly likely source of reentrant ventricular arrhythmias, Although most studies of the early phase of ventricular arrhythmias that follow acute ligation of a major coronary artery in the dog have shown some of the basic prerequisites for reentry in the form of desynchronized slow conduction in ischemic myocardium (1–8), they all fall short of actually documenting the presence of reentry. This was due, we believe, to the highly dynamic situation following acute ligation of a major coronary artery with constantly changing electrophysiological properties in the ischemic zone. Thus, it is difficult to conduct systematic electrophysiological studies of the possible reentrant mechanism under such dynamic conditions. In addition, the recording techniques usually failed to demonstrate the one unequivocal evidence for reentry, viz: the presence of continuous electrical activity originating from the infarction zone that regularly and predictably bridge the diastolic interval between the reentrant beat and the preceding impulse, as well as between consecutive reentrant beats (9).KeywordsInfarction ZoneReentrant TachycardiaCoupling IntervalConduction PatternSinus BeatThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.