Transfusion of blood and blood products in orthotopic heart transplantations were analysed in a series of 31 consecutive patients operated upon between September 1985 and December 1987. Mean age of the 29 men and 2 women was 41 +/- 12 years (range: 15-63). All patients had to be assigned to NYHA functional class IV before operation and their mean left ventricular fraction was 20%. The etiologies of cardiac disease leading to transplantation in this series were: cardiomyopathy in 19/31 patients (61%), ischemic heart disease in 7/31 (23%), valvular disease in 2/31 (6%), life threatening arrythmias in 2/31 (6%) and primary cardiac tumor in 1/31 (3%). Previous cardiac surgery had been performed in 6/31 patients (19%). Full anticoagulation with coumarines was observed in 24/31 patients (77%) at the time of surgery when mean PT was 33 +/- 12% and mean hematocrit was 40 +/- 4%. Mean blood products transfusion requirements in patients receiving an orthotopic heart transplant were 24.2 +/- 14.7 units (range 7-67 units) during the entire hospital stay. These figures are even higher if compiled in function of the number of donors of the transfused blood products: 29.2 +/- 22.4 (range 7-105). The following mean number of blood and blood components was perfused per patient: Red cells (hematocrit 50 +/- 10%) 4.4 +/- 3.9, concentrated red cells (hematocrit 70 + 10%) 5.9 +/- 4.3, fresh frozen plasma 7.4 +/- 3.3, platelets 3.9 +/- 4.1, and others (factor 8, 9 etc) 0.6 +/- 1.6. In-hospital mortality was 1/31 patients (3%) and actuarial survival is 27/31 (87%) at 33 months of follow-up (mean 17 +/- 7 months). However, 7/27 survivors (26%) had to be treated for cytomegaly acquired during or after the heart transplantation. Therefore transfusion of cytomegaly free blood products has to be recommended.