REVERSAL OF DONOR MYOCARDIAL DYSFUNCTION BY TRIIODOTHYRONINE REPLACEMENT THERAPY

Triiodothyronine deficiency after brain death can result in progressiv e deterioration of cardiac function in potential organ donors. We repo rt on the use of triiodothyronine replacement in improving myocardial function, allowing the use of donor hearts that might have been consid ered unsuitable for transplantation. From July to September 1992, of 2 4 organ procurements and transplantations, six donors were receiving h igh doses of inotropes with elevated left-sided filling pressures. Don or characteristics were as follows: five were male donors and one was a female donor, with mean age 16.50 +/- 7.50 years (8 to 30 years), me an weight 49.17 +/- 13.64 kg (25 to 63 kg), average time from clinical brain death to procurement 94.50 +/- 73.53 hours (49 to 240 hours), a nd two donors had arrest periods of up to 10 minutes. Despite large in otrope infusions, echocardiograms showed depressed left ventricular fu nction (mean ejection fraction 39.17 +/- 5.85) and hemodynamic instabi lity was present with elevated ventricular filling pressures. Triiodot hyronine replacement (maximal dose 0.6 mug/kg) was initiated an averag e of 139.17 +/- 32.00 minutes (115 to 185 minutes) before procurement. At the time of procurement, ventricular filling pressures were lower, hemodynamic condition stabilized, and pressor requirements decreased. Hearts were preserved in University of Wisconsin solution with a mean ischemic time of 188.83 +/- 36.86 minutes (149 to 237 minutes). Four hours after transplantation, hemodynamic data were as follows: mean sy stolic blood pressure 102.00 +/- 14.42 mm Hg (80 to 120 mm Hg), mean h eart rate 115.00 +/-14.14 beats/min (100 to 140 beats/min), mean centr al venous pressure 10.17 +/- 1.17 mm Hg (9 to 12 mm Hg), mean cardiac index 3.4 +/- 0.79 L/min/m2 (2.4 to 4.1 L/min/m2), mean dopamine 3.07 +/- 0.65 mug/kg/min (2 to 3.5 mug/kg/min), mean isoproterenol 1.03 +/- 0.40 mug/min, and two patients were receiving epinephrine, 2 mug/min. Echocardiograms at 1 week were normal, with an ejection fraction of g reater than 50% in all patients. All patients survived and were discha rged an average of 13.60 days (8 to 28 days) after transplantation; no ne required pacemakers. Triiodothyronine replacement is beneficial in salvaging donor hearts with depressed function. This therapy can incre ase the effective donor pool and help alleviate the critical shortage of donor organs.