PHARMACOLOGICAL POSTCONDITIONING OF REPER FUSION ARRHYTHMIAS BY ASPIRIN

DIEZ ER, LUCERO GA, PONCE ZUMINO AZ, MIATELLO RM.

Mendoza

Congreso; XXVI Annual Scientific Meeting of Cuyo Biology Society; 2008

Cuyo Biology Society

Ventricular fibrillation may occur within seconds after restoration of blood flow to myocardium turned ischemic by a period of coronary occlusion (reperfusion). The mechanisms of the beneficial cardiovascular effects of acetylsalicylic acid (ASA, aspirin) therapy are not completely understood. In this study, we tested the hypothesis that ASA treatment could reduce reperfusion arrhythmias acting during ischemia and/or during early reperfusion by an antiplatelet independent mechanism. We evaluate the effects of ASA 0.14mM perfused at the beginning of the experiment or only for 3 min after 10 min of regional ischemia in isolated rat hearts. ECG and membrane potential were synchronously recorded. ASA did not change any electrophysiological properties until reperfusion. Both ASA treatments reduce reperfusion ventricular tachycardia and/or fibrillation. Action potential duration was prolonged after ASA postconditioning when compared with continuous ASA perfusion, suggesting a modification only at reperfusion. The conclusions from this study were that acute aspirin treatment, infused at an early reperfusion period has similar beneficial actions than a continuous infusion of this compound and that this treatment only modify electrophysiological variables at reperfusion.