Dobutamine prevents both myocardial stunning and phosphocreatine overshoot without affecting ATP level.

Abstract Catecholamines can overcome myocardial stunning. However, a previous report on energy metabolism in stunned myocardium during catecholamine infusion was based on the conventional biochemical methods which might affect contractile function. Twenty farm pigs were anesthetized and underwent 15 min coronary artery occlusion and 2 h reperfusion. Ten pigs were given 10 μg/kg/min dobutamine from immediately after and throughout the reperfusion (dobutamine group). The other ten pigs were given saline (control group). Phosphorus-31 magnetic resonance spectroscopy and sonomicrometry were done alternately. Dobutamine improved percent segment shortening after reperfusion (control/dobutamine = 3.8% ∼ 5.7%/11.7% ∼ 13.4%; P