Combining cariporide with glyceryl trinitrate optimizes cardiac preservation during porcine heart transplantation.

Sodium-hydrogen exchange inhibitors, such as cariporide, are potent cardioprotective agents, however, safety concerns have been raised about intravenously (i.v.) administered cariporide in humans. The aim of this study was to develop a preservation strategy that maintained cariporide's cardioprotective efficacy during heart transplantation while minimizing recipient exposure. We utilized a porcine model of orthotopic heart transplantation that incorporated donor brain death and 14 h static heart storage. Five groups were studied: control (CON), hearts stored in Celsior; CAR1, hearts stored in Celsior with donors and recipients receiving cariporide (2 mg/kg i.v.) prior to explantation and reperfusion, respectively; CAR2, hearts stored in Celsior supplemented with cariporide (10 mumol/L); GTN, hearts stored in Celsior supplemented with glyceryl trinitrate (GTN) (100 mg/L); and COMB, hearts stored in Celsior supplemented with cariporide (10 mumol/L) plus GTN (100 mg/L). A total of 5/5 CAR1 and 5/6 COMB recipients were weaned from cardiopulmonary bypass compared with 1/5 CON, 1/5 CAR2 and 0/5 GTN animals (p = 0.001). Hearts from the CAR1 and COMB groups demonstrated similar cardiac function and troponin release after transplantation. Supplementation of Celsior with cariporide plus GTN provided superior donor heart preservation to supplementation with either agent alone and equivalent preservation to that observed with systemic administration of cariporide to the donor and recipient.

The effects of hormone resuscitation on cardiac function and hemodynamics in a porcine brain-dead organ donor model.

We compared the effects of hormone resuscitation (HR) with a norepinephrine-based protocol on cardiac function, hemodynamics and need for vasopressor support after brain death in a porcine model. Following brain death induction, animals were treated with norepinephrine and fluids for 3 h. In the following 3 h, they continued on norepinephrine and fluids (control) or received additional HR (triiodothyronine, methylprednisolone, vasopressin, insulin). Data were collected pre-brain death, 3 and 6 h post-brain death. At 6 h, median norepinephrine use was higher in controls (0.563 vs. 0 microg/kg/min; p < 0.005), with 6/8 HR animals weaned off norepinephrine compared with 0/9 controls. Mean arterial pressure was higher in HR animals at 6 h (74 +/- 17 vs. 54 +/- 14 mmHg; p < 0.05). Cardiac contractility was also significantly higher in HR animals at 6 h (stroke work index 1.777 vs. 1.494). After collection of 6 h data, all animals were placed on the same low dose of norepinephrine. At 6.25 h, HR animals had higher stroke work (3540 +/- 1083 vs. 1536 +/- 702 mL.mmHg; p < 0.005), stroke volume (37.2 +/- 8.2 vs. 21.5 +/- 9.8 mL; p < 0.01) and cardiac output (5.8 +/- 1.4 vs. 3.2 +/- 1.2 L/min; p < 0.005). HR in a porcine model of brain death reduces norepinephrine requirements, and improves hemodynamics and cardiac function. These results support the use of HR in the management of the brain-dead donor.