Patchy Myocardial Pattern of Virus Sequence Persistence in Heart Transplant Recipients—Possible Role of Sampling Error in the Etiology

Abstract

Background The pathway from viral myocarditis to end-stage heart failure is commonly accepted, but diagnosis of virus-mediated myocardial injury remains challenging. Virus persistency in the myocardium may accelerate ventricular failure; thus, a precise diagnosis of virus persistency may prevent the development of end-stage heart failure. Methods We performed a systematic investigation on the sampling error of viral diagnostics in heart transplant recipients: Transmural samples from 5 regions of the explanted hearts from recipients during heart transplantation were amplified using entero-, adeno-, and herpesvirus sequences and histologic examinations performed. Results We examined 175 myocardial samples from dilated cardiomyopathy and 100 samples from 20 forensic medicine patients. Seven patients were positive for the examined viruses: 10 positive regions for adenovirus, and 1 positive region for herpes virus DNA, but none for enterovirus. A focal myocardial pattern was detected for adenovirus. Conclusion Our results with the patchy myocardial viral persistence may explain possible false-negative results related to virus-mediated etiology among end-stage dilated cardiomyopathy patients. Therefore, repeated endomyocardal biopsies, and multiple cardiac samples are recommended to be obtained to evaluate the etiology of heart failure, thus reducing the occurrence of end-stage heart failure and decreasing the number of patients requiring heart transplantation.