Noninvasive Estimation of Pulmonary Capillary Wedge Pressure from Pulmonary Venous Flow Using Transesophageal Doppler Echocardiography

Abstract

We prospectively examined the relationship between pulmonary venous flow velocity determined by transesophageal echocardiography and pulmonary capillary wedge pressure (PCWP) determined with a Swan-Ganz catheter in 40 consecutive patients who were all in sinus rhythm and without significant mitral valve disease. Correlations were assessed between the four components of pulmonary venous flow – atrial reversal flow (A), early systolic (SI) and late systolic (S2) forward flow, and diastolic forward flow (D) – and PCWP. Multiple regression analysis showed that PCWP could be estimated from only two (S2 and D) among these four components. Thus, PCWP was estimated by using the following equation with a strong correlation (r = 0.83) to measured one by catheterization: PCWP = –0.07 × S2+0.27 × D+2.3 mm Hg. In addition, prospective estimation of PCWP by this equation in an additional 25 patients gave a good correlation with the measured values (r = 0.83). PCWP can be estimated by our new equation using the peak velocity of late systolic forward and diastolic forward flow in pulmonary vein in patients with various types of heart diseases.