Gender-dependent variability of signal-averaged electrocardiogram in acromegaly

Ventricular late potentials are obtained by signal-averaged surface electrocardiography. Late potentials in normal subjects may be influenced by physiological elements such as gender, height and body mass index. Considering that growth hormone (GH) hypersecretion is able to markedly alter different anthropometric variables, we studied the relation between these elements and the late potentials of 22 acromegalic patients. Males registered higher absolute QRS duration and LAS40 (low-amplitude signal) and, on the opposite, lower RMS40 (root mean square) in comparison to females; QRS duration and LAS40 seem to depend, however, on the different anthropometric variables, since their normalization with height and lean body mass (LBM) abolishes gender-dependent differences. On the contrary, the persistence, among males, of lower RMS40 in respect to females even after normalization for height, LBM and insulin-like growth factor 1 values makes it likely that the latter ECG variable is independent of the anthropometric ones and from the disease's activity. Moreover, males appear to be more vulnerable to GH heart-harming activity.