SUCCESSFUL TRANSPLANTATION AFTER LONG-TERM PRESERVATION OF DOG HEARTS

Nucleoside transport inhibition is a new approach to long-term preservation of donor hearts. To evaluate its effectiveness, the following were tested: 1) the effect of nucleoside transport inhibition on high-energy phosphate content after cardioplegic arrest and during long-term cold storage (group I: cardioplegia, control [n = 18]; group II: cardioplegia plus nucleoside transport inhibitor [n = 18]); 2) the effect of nucleoside transport inhibition on high-energy phosphates and hemodynamic recovery in a modified blood-perfused Langendorff system (group III: 24-h cold storage followed by reperfusion [n = 6]; group IV: addition of nucleoside transport inhibition to cardioplegia but not during reperfusion [n = 6]; group V: addition of nucleoside transport inhibition during reperfusion [n = 6]; group VI: addition of nucleoside transport inhibition to cardioplegia and during reperfusion [n = 6]); and 3) the effect of nucleoside transport inhibition added to cardioplegia and during reperfusion on high-energy phosphate content and outcome after heart transplantation (group VII: no nucleoside transport inhibitor in cardioplegia and during reperfusion [n = 8]; group VIII: addition of nucleoside transport inhibition to cardioplegia and during reperfusion [n = 8]). The following results were obtained: 1) addition of nucleoside transport inhibition prevented high-energy phosphate depletion during cold storage: after 24 h, adenosine triphosphate content in group I was 9.4 +/- 3.1-mu-mol/g versus 17.7 +/- 3.6-mu-mol/g dry weight in group II (P < 0.05); 2) addition of nucleoside transport inhibition to cardioplegia and during reperfusion resulted in greater high-energy phosphate content (adenosine triphosphate in group III was 7.9 +/- 3.5-mu-mol/g vs. 17.8 +/- 2.8-mu-mol/g in group VI [P < 0.051) and improved hemodynamics upon reperfusion (hearts in group III did not recover, maximum isometric left ventricular pressure development was 1,635 +/- 577 mmHg/sec in group IV, 1,915 +/- 423 mmHg/sec in group V, and 2,437 +/- 201 mmHg/sec in group VI [P < 0.05, group VI vs. groups IV and V]); and 3) hearts treated with nucleoside transport inhibition in cardioplegia and during reperfusion (group VIII) could be transplanted successfully in contrast to group VII hearts. These data indicate that nucleoside transport inhibition in dogs is highly effective in long-term preservation of donor hearts.