Comparative Histopathology of Endomyocardial Biopsies in Chagasic and Non-Chagasic Heart Transplant Recipients

Background: Heart transplantation has been an option for the treatment of chagasic (C) cardiomyopathy despite difficulties concerning the control of rejection and reactivation. The parasite-host interaction under the influence of immunosuppressive therapy may affect the immunological response to the graft in a pattern different from that in non-chagasic (NC) patients. The aim of this study was to compare the major histopathological features in heart transplantation in C and NC patients. Methods: We studied 293 endomyocardial biopsies from two groups of heart transplanted patients, including 18 C and 15 NC. Both groups had identical surgical and clinical procedure except immunosuppressive therapy was lower in C patients. The histopathological parameters evaluated were the Quilty effect, rejection, C myocarditis reactivation, fibrosis, hypertrophy, and ischemia. In addition, lymphocytic cellular infiltration of myocarditis due to rejection or reactivation was immunophenotyped in the biopsies of both groups with rejection grades 3 to 4, in biopsies with signs of reactivation, and in fragments of the receptor heart with chronic C myocarditis. A search for Trypanosoma cruzi was performed in all biopsies in the C group in whic