Color flow Doppler of mitral regurgitation

Panel A shows an apical four-chamber view with color flow Doppler of mild mitral regurgitation (MR); mild tricuspid regurgitation (TR) is also present. The regurgitant jets have a mosaic of color because their high velocities are represented by an aliased signal; they begin with a very narrow point of origin at the valve, remain narrow, and penetrate only partially into the left atrial (LA) cavity. These are characteristics of mild regurgitant lesions. In panel B, the size of the MR jet at the site of origin is wider, the jet reaches the posterior LA wall, and blood begins to accelerate before reaching the valve; these are characteristics of moderate to severe MR. In panel C, the jet is even wider, almost filling the LA, and it reaches the posterior LA wall and enters the pulmonary veins. Panel D is from a patient with rheumatic MR and a giant LA; proper gain settings show marked spontaneous echo contrast (D1). With slightly lower gain setting, spontaneous echo contrast is artifactually not seen (D2). Panel D3 shows a narrow jet of trivial mitral regurgitation (MR); spontaneous echo contrast does not develop when MR is moderate or severe.