Plakoglobin: A diagnostic marker of arrhythmogenic right ventricular cardiomyopathy in forensic pathology?

The histopathological diagnosis of arrhythmogenic right ventricular cardiomyopathy (ARVC) can be challenging in forensic medicine. Immunohistochemical myocardial analysis for plakoglobin has been suggested as a new diagnostic test for ARVC. We examined this in the setting of forensic pathology, applying this method to forensic autopsy samples. We performed immunohistochemical staining for plakoglobin on 40 myocardial samples with an autopsy diagnosis of ARVC. In addition, histopathological reevaluation was performed applying the revised 2010 task force criteria including morphometric analysis. Myocardial samples from 15 subjects without heart disease were used as controls. Based on the histopathological reevaluation, 38 out of 40 cases were categorized as ARVC. A marked reduction in the plakoglobin staining was seen in 26 out of 38 myocardial samples in the ARVC-group. Of the two samples categorized as not ARVC, one showed reduced plakoglobin staining and one sample had normal staining. No control samples showed reduced plakoglobin staining. In conclusion, our study displayed reduced plakoglobin staining in approximately 2/3 of myocardial samples with ARVC. Our data suggests that immunostaining for plakoglobin might serve as an additional diagnostic marker of ARVC in forensic pathology, but additional validation is required.