Hemodynamic observations in the early period after human heart transplantation.

Serial hemodynamic measurements, including determination of cardiac output by the Fick technique, were obtained in 10 human cardiac recipients for intervals up to 38 days after transplantation. Immediately postoperatively, donor cardiac output was severely depressed because of limitation of stroke volume. Spontaneous recovery of cardiac output and stroke volume then occurred gradually over the first 4 postoperative days to normal or nearly normal levels. Rate augmentation by arterial and/or ventricular pacing early after transplantation had little effect on donor heart performance, but isoproterenol caused significant enhancement of graft function and is now used routinely in postoperative management. Serial hemodynamic monitoring proved to be of little use in the prediction or confirmation of acute graft rejection episodes.