Terminal stage cardiac findings in patients with cardiac Fabry disease: an electrocardiographic, echocardiographic, and autopsy study

OBJECTIVES: Fabry disease is caused by deficiency of alpha-galactosidase A, and typically causes multi-organ dysfunction. Patients with manifestations limited to the heart, mainly left ventricular hypertrophy (LVH), have been reported as a disease variation. We have reported a 3% prevalence of this cardiac variant in men with LVH, which we designated 'cardiac Fabry disease'. The purposes of this study were to evaluate the terminal stage cardiac manifestations and autopsy findings in patients with cardiac Fabry disease. METHODS: We examined seven terminal stage patients with cardiac Fabry disease. During hospitalization, standard 12-lead electrocardiograms, Holter electrocardiograms, and echocardiograms were obtained. Autopsies were performed and macroscopic along with microscopic findings were evaluated. RESULTS: Six patients died of heart failure and one of ventricular fibrillation. Electrocardiograms revealed the presence of conduction abnormalities and nonsustained ventricular tachycardia. Echocardiograms and autopsy findings revealed LVH in all patients. Localized basal posterior wall thinning of the left ventricle was detected in the six patients who died of heart failure. All patients had severe left ventricular dysfunction. Histologically, myocardial cells, but not cardiac vascular endothelial cells, showed glycosphingolipid accumulation. No accumulation was observed in other organs or in systemic vascular endothelial cells. CONCLUSIONS: Severe left ventricular dysfunction with associated conduction disturbances and ventricular arrhythmias occur in patients with terminal stage cardiac Fabry disease. Furthermore, LVH is present and associated with thinning of the base of the left ventricular posterior wall. In contrast to typical Fabry disease, accumulation of glycosphingolipids was observed in myocardial cells but not in other organs.