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Updated: Aug 28, 2026
Heterotopic Heart Transplantation in Mice
Published on: July 18, 2007
Heterotopic heart transplantation in 1988--recent selective indications and outcome
H Reichenspurner1, A Hildebrandt, D Boehm
1Department of Cardiothoracic Surgery, University of Cape Town Medical School, Groote Schuur Hospital, South Africa.
Insights
Heterotopic heart transplantation remains indicated for specific cases, such as elevated pulmonary vascular resistance or significant size mismatch, showing an 83% 1-year survival rate. This procedure improves cardiac output and reduces pulmonary vascular resistance in select heart transplant recipients.
Area of Science:
- Cardiology
- Transplantation Surgery
- Immunology
Background:
- Orthotopic heart transplantation (OHT) boasts a high 1-year survival rate (nearly 90%).
- This raises questions about the continued role of heterotopic heart transplantation (HHT).
- This study reviews HHT outcomes at an institution with evolving immunosuppression protocols.
Purpose of the Study:
- To evaluate the indications and outcomes of heterotopic heart transplantation.
- To assess the efficacy of quadruple-drug immunosuppression therapy in heart transplant patients.
- To determine the impact of HHT on cardiac function and pulmonary hemodynamics.
Main Methods:
- Review of 132 heart transplantations performed since 1967.
- Analysis of 11 heterotopic heart transplantations performed between 1974-1983 and since 1985 with quadruple-drug immunosuppression.
- Quadruple-drug therapy: low-dose cyclosporine, azathioprine, methylprednisolone, and rabbit antithymocyte globulin.
- Right-sided heart catheterization for hemodynamic assessment post-transplantation.
Main Results:
- 11 HHT patients had indications of elevated pulmonary vascular resistance (PVR) or donor-recipient weight mismatch.
- The 1-year survival rate for HHT patients was 83%; 7 of 11 patients are currently alive.
- Significant improvements in cardiac output (4.0 to 5.8 L/min) and decreases in PVR (4.9 to 2.4 Wood units) were observed post-HHT.
Conclusions:
- Heterotopic heart transplantation remains a viable option for specific complex cases not suitable for OHT.
- The implemented quadruple-drug immunosuppression regimen is effective in managing heart transplant recipients.
- HHT effectively improves cardiac function and reduces pulmonary hypertension in selected patients.
Abstract:
Considering a worldwide average 1-year survival rate of nearly 90% after orthotopic heart transplantation, the question arises as to whether there is still an indication for heterotopic heart transplantation. Since 1967, 132 heart transplantations have been performed at our institution. From 1974 to 1983 only heterotopic transplantations were performed. Since 1985, quadruple-drug therapy has been used for immunosuppression. This consists of low dose cyclosporine in combination with azathioprine, methylprednisolone (in lower dosages), and rabbit antithymocyte globulin (for the first 4 to 6 days after operation and as rescue therapy for severe rejections). Fifty-five transplantations have been performed with this therapy (44 orthotopic and 11 heterotopic). The indications for heterotopic transplantations were either elevated pulmonary vascular resistance (4 to 6 Wood units, n = 6), or a gross donor and recipient weight mismatch (more than 20%) in candidates who showed signs of severe cardiac decompensation (n = 6). One patient had both indications. The 1-year survival rate for those patients was 83%. Currently seven of the 11 patients are alive with life spans ranging from 6 months to 2.5 years after operation. Causes of deaths were infections (n = 3) and chronic graft rejection (n = 1). The recipients were restudied with right-sided heart catheterizations performed from 2 months to 2 years after transplantation. In all patients the cardiac output increased significantly from a mean of 4.0 to 5.8 L/min (p less than 0.0005). In patients with elevated pulmonary vascular resistance, this value decreased after heterotopic transplantation from a mean of 4.9 to 2.4 Wood units.(ABSTRACT TRUNCATED AT 250 WORDS)
