Echocardiography was performed in 45 patients with aortic regurgitation. Forty showed a high frequency diastolic flutter of the mitral valve, which was holodiastolic in all but the patients with associated mitral stenosis. Of four patients with coexisting mitral stenosis, mitral flutter was absent in two; in the other two, in atrial fibrillation, mitral flutter occurred, but only during a fixed interval after mitral valve opening, irrespective of cycle length. A fine flutter of similar frequency was observed on the left ventricular aspect of the ventricular septum in 12 patients. In six of these it was of slight degree and restricted to early diastole and the high septum; in four others (three of whom had associated mitral stenosis), the septal flutter was more marked, holodiastolic, and present over all parts of the septum scanned; in two, it was holodiastolic over the high septum but early diastolic at lower septal levels. Aortography performed in 19 patients showed that septal flutter was present in seven of 12 patients in whom the regurgitant aortic jet was directed forward to the ventricular septum, whereas in the other seven patients with no septal flutter, the jet was directed away from the septum. Septal flutter is useful as an echocardiographic sign of aortic regurgitation, especially in the presence of mitral stenosis when mitral flutter may be absent or exceeded by septal flutter in both amplitude and duration, and when the mitral valve has been replaced by a prosthetic valve. Vibration of the septum appears to be attributable to the regurgitant aortic jet impinging on it and may contribute to the production and radiation of the characteristic diastolic murmur of aortic regurgitation.
Adolescent Adult