Haemodynamic studies during short-term preservation of the autoperfusing heart-lung preparation

Preservation of the donor heart in a viable state for even a few hours would greatly facilitate clinical cardiac transplantation. The autoperfusing heart-lung preparation has been investigated for periods of 2 to 6 has a means of short-term preservation of the heart. Its functional capability has been assessed by observations of a number of haemodynamic parameters, including those parameters believed to give an indication of the state of myocardial contractility. Although conversion of the normal circulation to that of the preparation was accompanied by considerable falls in max dP/dt and its derivative max dP/dt/P, there was a subsequent stabilization or improvement in these parameters during the period of autoperfusion. Haematoxylin-basic fuchsin-picric acid staining of the myocardium showed no evidence of myocardial ischaemia during the perfusion period. These observations, together with other haemodynamic and histological observations, suggested that myocardial perfusion by this technique was satisfactory. The effects of a coronary dilator such as dipyridamole have been observed, and its value in approximating the coronary and pulmonary blood flows in such a preparation is discussed. These studies would suggest that the autoperfusing heart-lung preparation can provide a simple and satisfactory form of short-term storage of the heart and, with further experience, may prove of value in clinical cardiac transplantation.