M-mode and cross-sectional echocardiographic features of flail aortic leaflets.

The echocardiographic features in seven patients with flail aortic leaflets are described and are correlated with the anatomical appearance of the valve at the time of surgery or autopsy. M-mode echocardiography showed coarse and "shaggy" diastolic echoes within the aortic root and thickening of the aortic leaflets during systole in all patients. Six patients had coarse and "shaggy" diastolic echoes within the left ventricular outflow tract in continuity with similar echoes within the aortic root. Cross-sectional echocardiography in three patients revealed a cord-like mass prolapsing into the left ventricular outflow tract during diastole. Three of the patients had no vegetations at the time of surgery. Both modes of echocardiography are of value in demonstrating abnormal echoes prolapsing into the left ventricular outflow tract, characteristic of flail aortic leaflets that can occur in the presence or absence of vegetations.