Immediate and short-term effects of aortic balloon valvuloplasty on left ventricular diastolic function and filling in humans

Abstract

The effect of aortic balloon valvuloplasty on left ventricular diastolic function and filling was investigated in 44 adult patients with severe aortic stenosis. Two-dimensional and Doppler echocardiography was performed in all patients before and 24 h after valvuloplasty. In 19 patients (short-term group) repeat studies were performed at 3 (n = 2) and 6 (n = 17) months. Left ventricular relaxation, chamber stiffness and filling were assessed in 16 patients (immediate post-valvuloplasty group) before and immediately after valvuloplasty by simultaneous micromanometer left ventricular pressure tracings and echocardiograms.Immediately after valvuloplasty, relaxation was slightly impaired in the immediate post-valvuloplasty group, as reflected by the isovolumic relaxation time constant (56 ± 26 to 68 ± 39 ms; p < 0.01) and maximal negative dP/dt (2,063 ± 640 to 1,767 ± 495 mm Hg/s; p < 0.001). The chamber stiffness constants and diastolic filling dynamics were unchanged immediately after valvuloplasty. Twenty-four hours after valvuloplasty, patients without mitral regurgitation (n = 24) showed increases in the peak early filling velocity (72 ± 31 to 83 ± 28 cm/s; p < 0.05) and peak early to atrial filling velocity ratio (0.8 ± 0.6 to 1.0 ± 0.7; p < 0.05). However, in patients with mitral regurgitation (n = 20), the diastolic filling dynamics were not significantly changed.In the short-term group at the 3 to 6 month follow-up period, patients without mitral regurgitation (n = 12) showed striking increases compared with pre-valvuloplasty values in the peak early filling velocity (66 ± 21 to 93 ± 31 cm/s; p < 0.02), peak early to atrial filling velocity ratio (0.6 ± 0.2 to 0.9 ± 0.4; p < 0.02) and early time-velocity integral (9 ± 4 to 16 ± 6 cm; p < 0.002). In patients with mitral regurgitation (n = 7) decreases occurred in the peak early filling velocity (123 ± 32 to 106 ± 28 cm/s; p < 0.05) and peak early to atrial filling velocity ratio (1.5 ± 0.7 to 1.1 ± 0.6; p < 0.05).Functional class in hospital improved after valvuloplasty (3.1 ± 1.0 to 2.6 ± 0.9; p < 0.001) and correlated modestly with the percent decrease in Doppler-derived peak gradient (rs= 0.41, p < 0.02) and mean gradient (rs= 0.36, p < 0.05), but did not correlate with changes in aortic valve area, left ventricular ejection fraction or diastolic filling variables. In the short-term group (n = 19), functional class before valvuloplasty (2.5 ± 0.9) improved significantly during the short-term period (1.8 ± 0.9; p < 0.02) and did not correlate with changes in aortic valve area and gradients, ejection fraction or diastolic filling.Diastolic function and filling do not improve immediately after aortic valvuloplasty. Contrasting effects on the diastolic filling pattern after valvuloplasty are seen in patients with, in contrast to those without, mitral regurgitation. The abnormal filling pattern (in patients without mitral regurgitation) normalizes over a 3 to 6 month period after aortic valvuloplasty. The improvement in functional class does not appear to be explained on the basis of improved diastolic function or filling.