Morphological Re-Evaluation of Cardiac Sarcoidosis　- A Case-Based Analysis of 14 Post-Mortem Japanese Hearts.

Background: Cardiac sarcoidosis is a major cause of secondary cardiomyopathy leading to lethal arrhythmias and heart failure; however, identifying specific imaging findings of cardiac sarcoidosis remains a major issue. We re-examined the macroscopic morphology of post-mortem hearts to identify and reconfirm crucial findings for the clinical diagnosis of cardiac sarcoidosis. Methods and Results: We examined 14 autopsied hearts from patients who were diagnosed with cardiac sarcoidosis from 2002 to 2019 at several medical institutions in Japan. The cases were classified into 2 groups: ante-mortem diagnosis (Group A, n=8), and post-mortem diagnosis (Group B, n=6). Of the 14 hearts, steroids were only administered in Group A. Seven macroscopic features were re-evaluated in all hearts: (1) epicardial irregularity (n=5); (2) fibrosis in the posterior interventricular junction (n=11); (3) ventricular septum wall thinning (n=9); (4) diffuse left ventricular wall thinning (n=4); (5) ventricular aneurysms (n=3); (6) papillary muscle deformities (n=12); and (7) white colored fibrosis (n=8). Conclusions: This study highlights the underreported macroscopic findings of cardiac sarcoidosis. The 7 features highlight the uniqueness of cardiac sarcoidosis, which warrants recognition of this disease as a distinct pathological entity rather than merely a dilated cardiomyopathy-like secondary cardiomyopathy.