The effect of aminophylline on right heart function in young pigs after ligation of the right coronary artery

An experimental model of right heart failure was developed to determine the effects of fluid loading and aminophylline on right heart function. We hyp othesised that aminophylline would specifically improve right heart functio n through a decrease in pulmonary vascular resistance and, possibly, an inc rease in cardiac contractility. Right heart infarct was induced in ten expe rimental pigs and seven control pigs by ligating branches of the right coro nary artery. The effect of fluid loading with a colloid solution and subseq uent bolus doses of aminophylline on haemodynamics was observed. Fluid load ing improved haemodynamics as expected. Aminophylline transiently improved cardiac index and pulmonary vascular resistance, but simultaneously caused an increase in heart rate and a decrease in stroke volume. Although aminoph ylline may reduce right heart afterload, it did not improve overall cardiac function in this experimental model of right heart infarction.