Ischemic Postconditioning's Benefit on Reperfusion Ventricular Arrhythmias Is Maintained in the Senescent Heart

Abstract

The purpose of this study is to determine if postconditioning's beneficial effect on ventricular arrhythmias is maintained in elderly hearts. In elderly populations, the cardioprotective effects of ischemic preconditioning are lost. Previously, the authors observed that ischemic postconditioning markedly reduced reperfusion-induced ventricular arrhythmias in adult rats. Whether this benefit is maintained in senescent hearts is unknown. Here, the authors study young adult rats compared with senescent animals. They chose 24-month-old Fischer female rats as these rats are approaching the end of their normal life span. Unlike some studies that suggest that the benefits of preconditioning and postconditioning are lost in the elderly, their data show that antiarrhythmic protection conferred by postconditioning is present in both the young and old rats.

Keywords

postconditioning ischemia/reperfusion myocardial infarction ventricular arrhythmias ventricular tachycardia

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