[Electro-vectorcardiographic study in Duchenne de Boulogne progressive muscular dystrophy].

Electrocardiographic changes are well known in Duchenne's muscular dystrophy (DMD). Their cause is still controversial. The aim of this study was: to verify the genetic theory of these changes to improve our understanding of their pathogenesis, by studying the distribution and characteristics of the mother carriers; to determine whether electro-vectocardiography could be of value in detecting carriers of the disease. Fourteen patients aged from 7 to 17 years old with DMD underwent ECG and VCG. ECG changes were recorded in 13 of the 14 cases: increased amplitude of the R wave in the right precordial leads or deep Q waves (amplitude greater than or equal to 2 mm, duration less than 0,04 msec) in the peripheral or left precordial leads. The algebraic sum of R--S in V1 was greater than normal in 6 carriers. VCG criteria of posterior myocardial infarction were fulfilled in 11 patients. "Bites" were recorded in 4 patients and 8 carriers. Electrical changes were therefore found in both patients and carriers with equal significance: in the first group the main appearances were of pseudo-infarction, principally involving the posterior wall; in the second group, less specific changes, best recorded on VCG, suggesting foci of myocardial fibrosis were observed. We think that the "bites" recorded in 66 p. 100 of mothers, could be a useful parameter for detecting carrier subjects.