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To investigate the relationship between age-related blood flow velocity and heart rate in the left ventricular inflow tract, we studied 118 healthy volunteers (age greater than 15 years). The maximal velocity (Vmax) of the transmitral diastolic flow during early ventricular filling (E) and during filling due to atrial contraction (A) was measured at 3 sites in the left ventricle with pulsed Doppler echocardiography. At all these sites a significant positive correlation was found between the VmaxA and the EA ratio and the interaction of heart rate and age. VmaxA increases if age and heart rate increase. The influence of the interaction of age and heart rate on VmaxA is most pronounced near the mitral annulus. VmaxA is only related to age and decreases with advancing age. Our observations contribute to the explanation of the more important role of the atrial contraction in the elderly.

The effects of aging on cardiac blood flow velocities are important as a description of the natural history of the aging process and as a reference for evaluation of the aging cardiovascular system. We therefore studied these effects in 215 healthy volunteers, 120 males and 95 females, between 1 and 65 years old. Pulsed Doppler signals were recorded proximal and distal to the mitral (M) and tricuspid (T) valves, in the left ventricular outflow tract (LVOT), in the ascending aorta (AAO), in the right ventricular outflow tract (RVOT), and in the pulmonary artery (PA). Systolic (S) flow velocity patterns consist mainly of one peak. Diastolic blood flow velocity is characterized by two peaks: one due to early filling (E) of the ventricle and a second as a result of atrial contraction (A). All peaks are characterized by the maximum of the median velocity curve (Vmax). With age increasing from 1 to 65 years, VmaxS decreases in the AAO (40%)and PA (10%), VmaxE decreases on both sides of the M valve (proximal—50%; distal—30%), and the T valve (proximal—20%; distal—30%). However, with increasing age VmaxS increases in the LVOT (25%), and VmaxA increases on both sides of the M valve (proximal—20%; distal—50%) and proximal to the T valve (30%). VmaxS in the RVOT and VmaxA distal to the T valve did not show a relation with age. These observations demonstrate that in a normal population Vmax in the heart and great vessels is age dependent at most sites. However, a positive or negative relationship can be found, depending on the measuring site and heart cycle phase. This behavior of Vmax must be taken into account in interpreting cardiac Doppler data for diagnostic purposes.