The assessment of the influence of body positional change on pulmonary venous flow by transesophageal Doppler echocardiography

We examined the profiles of right and left pulmoney venous flow (PVF) patterns and the influence of the body positional change on each wave using transesophageal Doppler echocardiography (TEE). Forty-six patients consisting of 13 normal subjects, 16 with coronary artery disease, 6 with aortic aneurysm, 5 with hypertension and 6 with hypertrophic cardiomyopathy were studied. All patients were sinus rhythm, and 5 with mital valvuar disease were excluded from the study. We recorded left and right PVF using TEE on supine position, and then on left lateral position. PVF consisted of a reverse flow at the atrial contraction (A wave) followed by systolic forward flows (S1, S2 wave) and diostolic forward flow (D wave). The following variables were measured : peak flow velocity of each wave (pA, pS1, pS2, pD), time-velocity integral of each wave (IA, IS1, IS2, ID), the time intervals between the beginning or P wave on ECG and A wave (P-A), between the beginning of P wave and S1 wave (P-S1), between the beginning of Q wave on ECG and S2 wave (Q-S2), between aortic somponent of the second heart sound on PCG and D wave (II a-D), dimensions of both pulmonary venis at the phase of atrial contraction. The time intervals of P-A(p＜0.05)、P-S1（ｐ＜0.01) and II a-D(p＜0.01) of the right PVF were significantly prolonged compared with those of left PVF, however, there were no significant differences between the left and right PVF in other variables. On the left lateral position, a dimension of left pulomonary vein was increased (p＜0.001 vs supine position), but no significant changes in left PVF were recoginized in other variables from on supine position. On the other hand, in the right PVF, a fusion of S1 and S2 waves were found in 81% of all subjects by changing the posture to the left lateral position, and also pA(p＜0.001), pS2(p＜o.o5), pd(p＜0.01), IA(p＜0.001), and ID/√<R－R>(p＜0.001) were increased, and Q-S2(p＜0.001) and a dimension of right pulmonary venis were decreased (p＜0.001). Thus, we concluded that (1) on supine position bilateral PVF showed similar patterns, however, the thing of each wave in the right pulmonary vein occurred later than those in the left pulmonary vein, which may be attributed to the morphological relation between both veins, (2) by changing the posture to the left lateral, right PVF pattern was significantly altered, which may be caused by the change in pulmonary blood flow distribution between right and left lungs, resulting from the elevation or hydrostatic pressure in the right lung.