Heterotopic Cardiac Transplantation: Long-term Results and Fate of the Native Heart

Background: The long-term results of heterotopic cardiac transplantation have not been well defined. Patient survival rates and the fate of the native heart remain unclear.

Methods: This study is a retrospective review of all 46 heterotopic cardiac transplantations performed at a single institution, the Texas Heart Institute in Houston, Texas, between 1982 and 2017. Four patients who underwent heterotopic transplantation as an emergency procedure for cardiogenic shock were excluded. Three of the procedures were repeat transplantations in patients who had previously undergone heterotopic transplantation; the 3 repeat transplantations were excluded, but the original procedures were not. Follow-up was 100% complete for mortality and 77% complete (30 of 39 patients) for assessment of preoperative indication for surgery and postoperative cardiac function.

Results: For the 39 patients, the 1-year, 5-year, and 10-year survival rates were 69%, 36%, and 21%, respectively. One patient remains alive 25 years after the transplantation procedure. The most frequent indication for heterotopic transplantation was pulmonary vascular resistance greater than 4 Wood units (n = 11), followed by weight greater than 112.5 kg (n = 7). In most patients, native heart left ventricular ejection fraction stabilized over time to between 10% and 30%. Sinus rhythm was preserved in 87% (26 of 30) of native hearts at long-term follow-up.

Conclusions: Heterotopic cardiac transplantation is an acceptable procedure that should be considered for obese patients (especially those heavier than 112.5 kg) and patients with elevated pulmonary vascular resistance (especially those with pulmonary vascular resistance >4.0 Wood units). After heterotopic transplantation, native cardiac function appears to stabilize, and there is potential for native heart recovery.