We evaluated the course of cardiac involvement in 27 previously reported @entity1 with @entity1555 ( @entity1555 ) originating from nine kindreds. Since almost all affected individuals of each kindred were included, intrafamilial variability could be studied. We also attempted to identify associations between cardiac involvement, functional ability and mutations at DNA level. The mean follow-up period was 12.5 years. The number of @entity1 with electrocardiographic abnormalities progressed from 44% to 71%. @entity384 ( @entity384 ) with or without @entity712 was now present in 33% as compared with 15% in the previous study. In addition, 22% developed borderline @entity854 . Six @entity1 (22%) became symptomatic and four @entity1 died of @entity712 . In all families @entity299 were found. There was no association between @entity384 and mutation type. Despite equal functional motor ability, there was a considerable intrafamilial variation in cardiac involvement, even in brother pairs. We conclude that @entity299 are the rule and not the exception in @entity1555 and are progressive over time. @entity5988 may begin at any moment in the course of @entity1555 and the rate of progression is unpredictable. A substantial proportion of @entity1 will develop an incapacitating and life-threatening @entity384 .

Evolution of @entity299 in XXXX over a 13-year period.

@entity1 :: ('9606', 'Species') :: ['patients'] @entity712 :: ('MESH:D006333', 'Disease') :: ['congestive heart failure'] @entity5988 :: ('MESH:C565277', 'Disease') :: ['Left ventricular dilatation'] @entity384 :: ('MESH:D002311', 'Disease') :: ['DCM', 'Dilated cardiomyopathy'] @entity1555 :: ('MESH:D020388', 'Disease') :: ['Becker muscular dystrophy', 'BMD'] @entity854 :: ('MESH:D018376', 'Disease') :: ['echocardiographic abnormalities'] @entity299 :: ('MESH:D006331', 'Disease') :: ['cardiac abnormalities']
@entity1555 :: (MESH:D020388,Disease) :: ['Becker muscular dystrophy']
