Effects of aspirin and indomethacin on ventricular arrhythmias- comparative study

ABSTRACT

The effects of aspirin and indomethacin on the ventricular arrhythmias produced by ligation [ischaemia] and unligation [reperfusion] of the circumflex branch of the left coronary vessel were evaluated in fifty male rabbits weighing 1.5 - 2 kg. Pretreatment of animals with aspirin [50 mg/kg i/v] suppressed all arrhythmias during ischaemia. Low dose of aspirin [12.5 mg/kg i/v] produced no mortality. Indomethacin [2.5 mg/kg] was unable to control ischaemia and reperfusion-induced ventricular arrhythamis. However, higher doses of indomethacin [50 mg/kg] suppessed ischaemia-induced arrhythamias to some extent but the mortality rate was increased [37%]. Fragment of ventricular fibrillation was zero during ischaemia after treatment with aspirin and indomethacin but reperfusion-induced ventricular fibrillation was not controlled by any of these drugs. Aspirin [12.5 mg/kg, 50 mg/kg] and indomethacin [2.5 mg/kg] significantly suppressed ischaemia - induced tachyarrhythmias while reperfusion induced tachyarrhythmias were suppressed only by aspirin. There was no significant effect on the mean arterial pressure after these drug treatments