Value of cardiac magnetic resonance imaging in the setting of familiar cardiomyopathy: A step toward pre-clinical diagnosis

Abstract

A 24-years-old asymptomatic man was referred to our Institution for screening of familiar idiopathic dilated cardiomyopathy (CMP) due to the important family history of dilated CMP with associated severe burden of ventricular arrhythmias (Fig. 1). His father and a first-degree father's cousin were indeed both affected by idiopathic dilated CMP, which was diagnosed in their third decade after an episode of sustained ventricular tachycardia (VT); both underwent implantable cardioverter defibrillator (ICD) implantation for secondary prevention of sudden cardiac death (SCD) and subsequently experienced multiple appropriate ICD interventions. Due to further dilatation and dysfunction of the left ventricle (LV) and worsening of the arrhythmic burden as well as heart failure symptoms despite optimal medical therapy, they were finally referred to heart transplantation at the age of 40 and 45 years, respectively. In addition, two more first-degree father's cousins died suddenly at the age of 14 and 47 years. The histologic examination of the explanted heart of proband's father showed multiple areas of dense fibrosis with intra-myocardial and sub-epicardial patchy distribution (Fig. 2A –B, Mallory trichromic stain: blue areas); myocyte apoptotic and degenerative phenomena were also observed (Fig. 2C–D, arrows). Of note, a strong family history of breast cancer was also present in the family (Fig. 1). Fig. 2Cardiomyopathy-related myocardial morphological changes are shown in histological sections of the explanted heart of the proband's father. They consist of a spectrum of changes beginning with focal degeneration and necrosis of cardiomyocytes with no or minimal cellular response, followed by myofiber loss and replacement of the cardiomyocytes with varying degrees of fibrosis. Low magnification shows intra-myocardial (A) and sub-epicardial (B) areas of dense fibrotic scar with patchy distribution (blue with Mallory trichromic stain). Higher magnification reveals foci of myocardial degeneration with vacuolization of cardiomyocytes (panel C–D, arrows, Hematoxylin and Eosin stain). Necrotic cardiomyocytes exhibit homogeneously brightly eosinophilic sarcoplasm with pyknotic or karyorrhectic nuclei (panels C–D, arrows). View Large Image Figure Viewer Download Hi-res image