Reperfusion ventricular tachyarrhythmias: correlation with antecedent coronary artery occlusion tachyarrhythmias and duration of myocardial ischemia.

The incidence and severity of reperfusion ventricular tachyarrhythmias were correlated with : (1) the duration of antecedent acute coronary artery occlusion and (2) the incidence, severity, and time course of ventricular tachyarrhythmias occurring during the antecedent period of coronary occlusion in 98 dogs studied postligation for 5 to 60 minutes. The incidence of reperfusion ventricular fibrillation (VF) increased significantly as coronary artery ligation periods were lengthened from 5 minutes to either 20 minutes (2 of 19 dogs vs 12 of 18 dogs, p less than 0.001) or 30 minutes (16 of 24, p less than 0.001), but notably decreased when reperfusion was delayed further from 30 minutes to 60 minutes after coronary artery ligation (4 of 18 dogs, p less than 0.001). Seven dogs were resuscitated from VF during coronary ligation and all seven suffered VF on reperfusion, whereas 37 dogs were arrhythmia-free during ligation and only one (3%, p less than 0.001) had VF on reperfusion. In addition, reperfusion ventricular tachyarrhythmias correlated with the occurrence of both immediate ventricular tachyarrhythmias (those peaking at 5 to 6 minutes postligation) and delayed ventricular tachyarrhythmias (those peaking at 18 minutes' postligation) of the antecedent acute ligation period. These observations provide a further basis for improved clinical understanding and management of potentially malignant tachyarrhythmias consequent to early myocardial reperfusion following acute myocardial ischemia and infarction.