[Cardiac changes induced by deconditioning in athletes: an echocardiographic and electrocardiographic study].

The relationships between echocardiographic and electrocardiographic variations and the sensibility of three different electrocardiographic criteria of left ventricular (LV) hypertrophy were assessed during deconditioning in 18 top-level oarsmen (mean age 23 +/- 4 years). After seven months of training and on the 7th and 21st deconditioning days the oarsmen underwent clinical examination, electrocardiogram (ECG) and echocardiogram with Doppler evaluation. The following ECG measurements were obtained: heart rate (HR), QTc, QRS and T waves axes, QRS and T wave angular gradients, R, S and T wave amplitude and T wave area. Moreover, the sums of S wave in lead V1 plus R wave in lead V5 or V6, of S wave in lead V1 or V2 plus R wave in lead V5 or V6, and of R wave in lead aVL plus S wave in lead V3 were calculated as indices of left ventricular hypertrophy. The following echocardiographic parameters were also analyzed: intraventricular septal (IVST) and posterior wall thickness (PWT), LV internal diameter (LVID), left ventricular mass (LVM) and volumes, LV endocardial/epicardial diastolic surface area ratio, peak systolic meridional wall stress (PSS), end-systolic stress (ESS) and mean systolic wall stress (MWSI), LV ejection fraction (EF) and total peripheral resistances (TPR); early (E) and late (A) transmitral peak flow velocity, E/A ratio. Systolic blood pressure was reduced after 3 deconditioning weeks, while diastolic blood pressure and HR were unchanged. Left ventricular mass and end-systolic volume were reduced after 1 week, while LV end-diastolic volume only after 3 weeks; therefore, EF improved at the end of the first week when TPR were lower. End-systolic stress always remained unchanged; PSS increased at 1 week and then returned to previous values. In addition, the endocardial-epicardial area ratio increased after 1 week and then returned to starting values after 3 weeks. Doppler parameters were in the normal range and remained unchanged during the study. Amplitudes of R wave in aVL, V5, V6 and of S wave in V2 did not change, while S wave amplitude in V1 and V3 decreased after three weeks and one week, respectively. The most sensible criterion for LV hypertrophy was the sum of S wave in V1 or V2 plus R wave in V5 or V6 (range from 33.3% to 22.2%); the sum of S in V1 plus R in V5 or V6 performed better than the sum of R in aVL plus S in V3.(ABSTRACT TRUNCATED AT 400 WORDS)