Rapid systolic intraventricular velocities after valve replacement for aortic stenosis

To assess the frequency and severity of intraventricular gradients after valve replacement for severe valvular aortic stenosis 25 patients (valve area 0.59 +/- 0.19 cm2) were studied serially with Doppler echocardiography on postoperative days 1, 2, 3, 5 and 7. Pulsed Doppler was used to search for increased intraventricular velocities. Mid-to-late systolic intraventricular velocities > or = 2 m/s were defined as intraventricular gradients. In 13 patients (52%) intraventricular gradients were found at least once during days 1 to 7 (group A) and were most frequent at day 3 (44%). The typical location of these velocities was at the midventricular level close to the septum. In 4 patients intraventricular gradients > 64 mm Hg were found. Left ventricular end-diastolic and end-systolic diameters recorded preoperatively were significantly smaller in group A than in the rest (43.6 +/- 5.4 vs 50 +/- 5.8 mm and 24.6 +/- 5.6 vs 33.1 +/- 7.3 mm, both p < 0.05) and the fractional shortening was significantly higher (44 +/- 9 vs 34 +/- 9%, p < 0.05). It is concluded that intraventricular gradients are frequent during the first week after valve replacement for severe aortic stenosis. These gradients are mostly mild and transient in nature, but significant gradients associated with clinical deterioration may occur. The risk of developing intraventricular gradients postoperatively may be predicted at a preoperative echocardiographic examination, and patients with a small left ventricular cavity size and maintained contractility are at particular risk.(ABSTRACT TRUNCATED AT 250 WORDS)