Electrocardiographic and echocardiographic findings in muscular dystrophy patients with heart failure

Cardiac involvement in muscular dystrophy (MD) is known to cause heart failure (HF). However, little is known about the differences in electrocardiographic and echocardiographic findings between MD patients with and without the experience of hospitalization for HF. We retrospectively identified 95 MD patients (mean age at diagnosis of MD 41.1 +/- 18.7years; males 64.2%), including nine (9.4%) patients who were hospitalized for HF (the HF group) and 86 (90.6%) patients who were not (the non-HF group) during the follow-up period (16.7 +/- 12.2years). The HF group had a significantly wider QRS duration (126.0 +/- 37.6 vs. 98.1 +/- 16.7ms, p<0.001) and QTc interval (454.6 +/- 50.5 vs. 409.5 +/- 23.6ms, p<0.001) at the time of HF hospitalization than the non-HF group. The HF group also had a significantly lower left ventricular (LV) ejection fraction (35.4 +/- 19.2 vs. 62.5 +/- 11.3%, p<0.001) and significantly larger diastolic LV dimension (64 +/- 2 vs. 45 +/- 1mm, p<0.001) and left atrial diameter (38 +/- 12 vs. 29 +/- 6mm, p=0.003) at the time of HF hospitalization than the non-HF group. In the HF group, the QRS duration was significantly wider at the time of HF hospitalization than at the initial electrocardiogram before the development of HF (129.8 +/- 30.7 vs. 119.0 +/- 33.3ms, p=0.018). This study suggests that HF occurs in MD patients with electrocardiographic and echocardiographic abnormalities. Early recognition of abnormal findings during a regular electrocardiographic or echocardiographic follow-up may be useful for identifying cardiac involvement in MD.