Left ventricular diastolic function in congenital myotonic dystrophy.
OBJECTIVE
Examination of left ventricular function and conduction abnormalities in myotonic dystrophy.


METHODS
Twelve patients (median age, 13.7 years) with myotonic dystrophy had detailed electrocardiography and echocardiography performed. Echocardiographic parameters were compared with body surface area (BSA) matched median normal values.


RESULTS
Fractional shortening was slightly reduced (by 28-29%) in three patients and three patients had mild mitral valve prolapse. Diastolic function was abnormal; isovolumic relaxation time (IVRT) and duration of early filling were prolonged compared with control values (median IVRT, 74 v 61 ms). Peak E velocity was increased (median, 0.82 v 0.78 m/s) but atrial phase filling was normal. Heart rate was reduced (median, 68 v 81 beats/min). Conduction abnormalities were common but showed no clear relations with diastolic abnormalities.


CONCLUSIONS
Young patients with myotonic dystrophy have myocardial diastolic dysfunction as well as abnormal electrophysiology. The prognostic implications of such abnormalities require further study.
D000293:Adolescent; D000328:Adult; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D003971:Diastole; D015150:Echocardiography, Doppler; D015716:Electrocardiography, Ambulatory; D005260:Female; D006801:Humans; D008297:Male; D009224:Myotonia Congenita / Q000000981:diagnostic imaging / Q000503:physiopathology*; D012044:Regression Analysis; D018709:Statistics, Nonparametric; D018487:Ventricular Dysfunction, Left / Q000503:physiopathology*