Click on image to view larger version.

Figure 4 (A) Simultaneous recording of the pulmonary venous flow (PVF) using transesophageal echocardiography and left atrial pressure (LAP) in patients with 4+ mitral regurgitation (MR). The pulmonary venous systolic wave (S) was blunted, and late systolic reversal flow (SRF) was observed corresponding to the large LAP "v" wave. (B) Relationship between LAP and PVF in 2+, 3+, and 4+ MR. As MR grade increases, the "v" wave and "v-y" descent increase, and the "a" wave and "a-x" descent decrease, which is consistent with decrease in S wave, increase in D and SRF waves. ECG = electrocardiogram. From Klein AL, Savage RM, Kahan F, et al. Experimental and numerically modeled effects of altered loading conditions on pulmonary venous flow and left atrial pressure in patients with mitral regurgitation. J Am Soc Echocardiogr 1997;10:41–51; reproduced with permission.