Detection and management of cardiomyopathy in female dystrophinopathy carriers.

Regular health checkups for mothers of patients with Duchenne muscular dystrophy have been performed at National Hospital Organization Tokushima Hospital since 1994. Among 43 mothers participated in this study, 28 dystrophinopathy carriers were identified. Skeletal and cardiac muscle functions of these subjects were examined. High serum creatine kinase was found in 23 subjects (82.1%). Obvious muscle weakness was present in 5 (17.8%) and had progressed from 1994 to 2015. Cardiomyopathy was observed in 15 subjects (60.0%), including dilated cardiomyopathy-like damage that was more common in the left ventricular (LV) posterior wall. Late gadolinium enhancement on cardiac MRI was found in 5 of 6 subjects, suggesting fibrotic cardiac muscle. In speckle tracking echocardiography performed seven years later, global longitudinal strain was decreased in these subjects, indicating LV myocardial contractile abnormality. These results suggest that female dystrophinopathy carriers should receive regular checkups for detection and treatment of cardiomyopathy, even if they have no cardiac symptoms.

[A clinicopathological investigation of two autopsy cases of calpainopathy (LGMD2A)].

In this study, we compared the clinicopathological findings of two autopsy cases of patients with calpainopathy (LGMD2A) from different families. The patient in case 1 was a 72-year-old man with a history of type 2 diabetes mellitus. He exhibited recent memory impairments from the age of 70. ECG revealed an incomplete right bundle branch block. A homozygous frameshift mutation c.1796dupA was found in the CAPN3 gene. Cause of death was respiratory insufficiency and heart failure. The patient in case 2 was a 70-year-old man with a history of hypertension. ECG revealed an incomplete right bundle branch block. A homozygous missense mutation c.1080G>C (p.Trp360Cys) in CAPN3 gene was identified. Cause of death was ischemic cardiomyopathy and systemic circulatory failure. In both cases, muscle pathology revealed severe dystrophic changes. In case 2, cardiac hypertrophy and old myocardial infarcts with stenosis of coronary arteries were observed. Histological examination of the sinoatrial node showed fatty infiltration with ischemic changes in case 2. In both cases, the patients' brains showed cerebral atrophy and well preserved neurons. Calpain 3 abnormality was correlated with skeletal muscle involvement. It should be considered that LGMD2A might be complicated by dysfunction of the cardiac conduction system.