ESTIMATING MEAN PULMONARY WEDGE PRESSURE IN PATIENTS WITH CHRONIC ATRIAL-FIBRILLATION FROM TRANSTHORACIC DOPPLER INDEXES OF MITRAL AND PULMONARY VENOUS FLOW VELOCITY

Objectives. We sought to obtain a noninvasive estimation of mean pulmo nary wedge pressure (MPWP) in patients with chronic atrial fibrillatio n (AF). Background. It has previously been demonstrated that MPWP fan be reliably estimated from Doppler indexes of mitral and pulmonary ven ous how (PVF) in patients with sinus rhythm. Doppler estimation of MPW P has not been validated in patients with AF. Methods. MPWP was correl ated with variables of mitral and pulmonary venous flow velocity as as sessed by Doppler transthoracic echocardiography in 35 consecutive pat ients. The derived algorithm aas prospectively tested in 23 additional patients. Results. In all patients the mitral flow pattern showed onl y a diastolic forward component. A significant but relatively weak cor relation (r = -0.50) was observed between MPWP and mitral deceleration time. In 12 (34%) of 35 patients, the pulmonary vein how tracing demo nstrated only a diastolic forward component; a diastolic and late syst olic forward flow was noted in the remaining 23 patients (66%). A stro ng negative correlation was observed between MPWP and the normalized d uration of the diastolic flow (r = -0.80) and its initial deceleration slope time r = -0.91). Deceleration time >220 ms predicted MPWP less than or equal to 12 mm Hg with 100% sensitivity and 100% specificity. When estimating MPWP by using the equation MPWP = -94.261 PVF decelera tion time - 9.831 Interval QRS to onset of diastolic PVP - 16.337 Dura tion of PVF + 44261, the measured and predicted MPWP closely agreed wi th a mean difference of -0.85 mm Hg. The 95% confidence Limits were 4. 8 and -6.1 mm Hg. Conclusions. In patients with chronic AF, MPWP can b e estimated from transthoracic Doppler study of PVF velocity signals. (C) 1997 by the American College of Cardiology.