Pulsatile Perfusion: Its Effects on Blood Flow Distribution in Hypertrophied Hearts

Left ventricular hypertrophy was created in 15 pigs by banding the ascending aorta when they were young. The adult animals were placed on normothermic cardiopulmonary bypass and perfused with either nonpulsatile (two groups of pigs) or pulsatile (one group) flows. As long as the perfusion rate was maintained at 70 ml/kg/min, myocardial blood flow distribution, as determined by radioactive microspheres, was identical in the hearts with normal sinus rhythm and those with ventricular fibrillation irrespective of the type of perfusion. At low flow rates, however, subendocardial ischemia developed in all three groups, but was most severe in the fibrillating hearts, and was not reversed by pulsatile perfusion.