Left atrial systolic antegrade flow in patients with mitral regurgitation: a pulsed Doppler sign displayed by color flow imaging

Twenty-two patients with severe mitral regurgitation were observed to have turbulent systolic antegrade flow on pulsed Doppler mapping of the left atrium. All were studied by color flow imaging to delineate the mechanism of this peculiar flow. Pulsed Doppler findings of an eccentric regurgitant flow in one side, an antegrade systolic flow with slightly delayed onset in the other side, and a low velocity flow near the posterior wall, were consistant with the theory of a large eccentric regurgitant jet swirling in the left atrium. Color flow imaging confirmed this mechanism in all patients. Nineteen patients had flail mitral valve with a positive predictive value of 86%. The other three patients had deformed rheumatic mitral valve. The severity of mitral regurgitation was confirmed in all 16 patients studied by left ventricular cineangiography. We have shown that the antegrade systolic left atrial flow is the result of the swirling of a large regurgitant eccentric jet, is commonly observed with flail mitral valve, can occur in patients with deformed rheumatic mitral valve without flail leaflet, and most significantly indicates the presence of severe mitral regurgitation.