[The apex cardiogram in normal aged subjects].

In 25 healthy subjects aged 60-88 years (mean 74.5) and in 20 healthy subjects aged 16-32 years (mean 23.6) apexcardiographic indices were studied as a function of age. The apex cardiograms (ACG) were obtained using a non-calibrated displacement transducer. With the help of an interactive computer program, 17 ACG indices of systolic and diastolic function were computed. The indices were divided into 2 groups (according to the nomenclature proposed by their Authors): a) systolic indices: electromechanical ventricular interval q-C, systolic upstroke time C-E, time from the beginning of ventricular depolarization to the peak of the first ACG derivative q-dA/dt, time from the onset of systolic slope to the peak of first ACG derivative C-dA/dt, ejection fraction according to Antani et al. 1979 E.F.; b) diastolic indices: electromechanical atrial interval P-a, atrial wave length d.a., height of atrial wave as percent of total ACG deflection a/H, height of atrial wave as percent of total diastolic deflection a/D, ratio of the diastolic wave to the total ACG height D/H, total rapid filling cR, early filling period EFP, rapid filling period RFP, total apexcardiographic relaxation time TART, duration of diastolic period A2-C, total apexcardiographic relaxation time index TARTI and diastolic amplitude time index DATI. Several diastolic indices (a/D, a/H, TART, electromechanical atrial time) were markedly higher (p less than 0.001) or lower (TART and DATI, p less than 0.001) in the older group. Systolic indices showed less significant differences: the electromechanical interval lengthened in the older group (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)