The heart in becker muscular dystrophy, facioscapulohumeral dystrophy, and bethlem myopathy

Abstract

We report a study, assessing involvement of the heart in 33 familial cases of Becker muscular dystrophy (BMD), 31 familiar cases of facioscapulohumeral (FSH) dystrophy, and 27 familial cases of Bethlem myopathy. In the patients with BMD, correlations of myocardial involvement with age and extent of musculoskeletal involvement were made. We performed physical examination, chest x-ray, electrocardiographic (EKG), and echocardiographic examination on all patients, and continuous EKG Holter-monitoring in the patients with FSH dystrophy. Thirteen patients with BMD (45%) showed EKG changes similar to those found in Duchenne muscular dystrophy. Only 1 of the 13 individuals with cardiac involvement was wheelchair-bound. We found no evidence of cardiac changes in the patients with FSH dystrophy. In Bethlem myopathy, only 1 patient had a form of hypertrophic cardiomyopathy (asymmetrical septal hypertrophy).

Evolution of cardiac abnormalities in Becker muscular dystrophy over a 13-year period

“…In a cross-sectional study we conducted in 1980 it was shown that nearly half of patients had ECG changes and 15% had DCM [12]. Our findings have been confirmed by others [11,23,32,33,45].…”

“…Twenty-four patients originating from nine kindreds agreed to be seen again. A clear Xlinked recessive mode of inheritance was found in seven kindreds [12]. In five of these families and in one of the two remaining families, a mutation was found.…”

“…They found an increase in clinically evident cardiomyopathy with increasing age during a mean follow-up period of 8 years [33]. We were able to evaluate the course of cardiac involvement in 29 previously reported individual patients with BMD originating from nine kindreds [12], with a mean follow-up period of 12.5 years. Since almost all affected individuals of each kindred were included, intrafamilial variability could be studied.…”

“…In BMD estimates of the prevalence of abnormal cardiac findings vary from 17% to 74% [1,11,12,21,23,32,45]. Dilated cardiomyopathy (DCM) in BMD is independent of age and severity of muscle weakness [1,11,12,23,41,45]. It can even be the only clinical manifestaAbstract We evaluated the course of cardiac involvement in 27 previously reported patients with Becker muscular dystrophy (BMD) originating from nine kindreds.…”

“…Electrocardiographic (ECG) changes similar to those seen in DMD can be found in 41%-74% of BMD patients [7,11,12,23,45]. Echocardiographic abnormalities, including global hypokinesia [11,23,45], left ventricular dilatation or DCM [11,12,23,45], right ventricular dilatation [23], hypertrophic cardiomyopathy [20,32,33] and other wall motion abnormalities [11,23,45] are seen in 17%-67% of patients [11,12,23,32,45]. Despite the high proportion of DCM in BMD, symptomatic patients are not common.…”