Toxoplasmosis of donor and recipient hearts after heterotopic cardiac transplantation.

Toxoplasmosis of both donor and recipient hearts was diagnosed by means of endomyocardial biopsy specimens after heterotopic cardiac transplantation for dilated cardiomyopathy. Before transplantation, the donor had raised antibody titers to Toxoplasma, and the recipient was negative. When toxoplasmosis was diagnosed on the basis of endomyocardial biopsy specimen, the recipient had a greatly elevated antibody titer of 1:1,027. This suggests that the infection could have been transferred with the donor heart. The mononuclear cell response elicited by disrupted toxoplasmic cysts interferes with the diagnosis of rejection in graft biopsy specimens. Electron microscopy is valuable in confirming a light microscopic diagnosis of toxoplasmosis. Drug therapy eradicated the toxoplasmosis, but the patient died later of tuberculous meningitis.

Changes in indications for heart transplantation. An additional argument for the preservation of the recipient's own heart.

The 1 year survival rate after heart transplantation since 1967 from +/-30% to +/-70%, and the 5 year survival rate is now +/-50%. This improvement has brought renewed interest in this procedure, now done in about twenty centers in eight countries, and increased confidence has widened the indication to patients who are less than terminally ill, to restore quality of life. This trend is illustrated by the Cape Town series, which can be divided into two parts: 10 patients treated by orthotopic heart transplantation (OHT), from 1967 to 1973, and 40 patients treated by heterotopic heart transplantation (HHT), from 1974 to 1981. The HHT group was younger (mean 37 +/- 10 years versus 51 +/- 9 years, p less than 0.001), had been ill for a shorter length of time (mean 3.6 +/- 0.7 years versus 6.6 +/- 1.4 years, p less than 0.091), and were in a lower New York Heart Association (NYHA) class (mean 3.45 +/- 0.11 versus 3.9 +/- 1.0, p less than 0.006). The improved survival is linked to patient selection, progress in management, and switch to HHT, but not to progress in matching between donor and recipient. Since there is no means to predict tolerance of the donor heart, HHT limits the risks from unforseeable mismatch. The recipient's heart is a built-in assist device, maintaining life when the donor heart fails acutely at operation or during acute [three cases] or chronic [two cases] rejection. Had these patients undergone OHT they would have died. Comparing the 10 oldest HHT patients with the OHT series, no difference in pretransplant parameters was found. However, survival of HHT recipients was longer during the critical post-HHT period: at 3 months, p less than 0.011; at 6 months, p less than 0.05. Larger series will separate the effects of progress in management from the intrinsic advantages of HHT. Retaining the recipient's heart is logical and has brought few complications. Survival rate of 40 HHT patients was 73% at 6, 65% at 12, and 51% at 36 months; 85% of survivors are in NYHA Class I. In patients in less than desperate condition, but who refuse to remain cripples, HHT eliminates the growing ethical problem of removing a recipient's heart that may still support the patient.

The present status of heterotopic cardiac transplantation.

In the period November, 1974 to May, 1980, 30 patients underwent heterotopic heart transplantation at Groote Schuur Hospital. One patient subsequently underwent retransplantation for rejection. There were no operative deaths. Fifteen patients are alive 4 months to almost 5 1/2 years after transplantation. The 1 year survival rate has been 61%. Three of six patients have survived for more than 4 years. Eight of nine patients whose initial transplant operation was performed during the past 18 months remain alive. Seven patients died from infection, five from rejection, and three from other causes. The advantages of heterotopic over orthotopic heart transplantation, in particular in allowing patients survival even after graft destruction by irreversible rejection, are discussed.