Doppler-Derived Mitral and Pulmonary Venous Flow Variables Are Predictors of Pulmonary Hypertension in Dilated Cardiomyopathy

This study assessed whether Doppler‐derived mitral and pulmonary venous flow parameters were predictors of pulmonary artery hypertension in patients with left ventricular dysfunction. Doppler echocardiographic examinations were performed in patients (n= 100) with dilated cardiomyopathy in sinus rhythm either symptomatic or asymptomatic before and after optimized therapy with ACE inhibitors, diuretics, and vasodilators. In case of weak or poor Doppler signals, measurable tricuspid regurgitation and pulmonary venous flow tracings were obtained after intravenous administration of 2.5 grams of Levovist at 400 mg/ml. At baseline, left ventricular ejection fraction was 30%± 7% and pulmonary artery systolic pressure was 48 ± 14 mmHg. At the follow‐up study carried out after 6 ± 2 months, reversibility of pulmonary artery hypertension was apparent only in those patients exhibiting favorable changes of mitral flow curve from the restrictive or pseudonormal to impaired relaxation pattern (53 ± 7 mmHg vs 38 ± 8 mmHg; P < 0.0001). Numerous variables correlated significantly with pulmonary artery systolic pressure at baseline, while the correlations were generally weaker at the follow‐up study. The closest correlations were found with E wave deceleration rate (r= 0.73) at baseline and with the systolic fraction of pulmonary venous flow forward peak velocities (r=−0.67) at follow‐up. The stepwise regression model showed that the E wave deceleration rate and the degree of mitral regurgitation were the strongest independent predictors of pulmonary hypertension at baseline, while the ratio between pulmonary venous flow reverse and mitral wave velocities at atrial systole and ejection fraction added minor contributions, leading to a cumulative r value of 0.81. The systolic fraction was the strongest at the follow‐up study, with minor contributions provided by the E wave deceleration rate and the left atrial dimension index, leading to a cumulative r value of 0.71.