Echocardiographic Assessment of Pulmonary Hypertension in Patients with Advanced Lung Disease

TLDR

Doppler echocardiography is widely used to estimate systolic pulmonary artery pressure and diagnose pulmonary hypertension, yet its utility in advanced lung disease remains poorly characterized. The study investigated the performance of echocardiography versus right heart catheterization for estimating systolic pulmonary artery pressure and diagnosing pulmonary hypertension in 374 lung transplant candidates. The authors compared echocardiographic estimates with right heart catheterization measurements in a cohort of 374 lung transplant candidates. Among the 374 candidates, pulmonary hypertension prevalence was 25%; echocardiography estimated systolic pulmonary artery pressure in 44% of patients, showing a good correlation (r = 0.69) but with 52% inaccurate estimates and 48% misclassification, yielding sensitivity 85%, specificity 55%, PPV 52%, and NPV 87%, and overall leading to considerable overdiagnosis.

Abstract

Doppler echocardiography is commonly used to estimate systolic pulmonary artery pressure and to diagnose pulmonary hypertension, but data relating to its utility in patients with advanced lung disease are limited. In a cohort study of 374 lung transplant candidates, the performance characteristics of echocardiography compared with right heart catheterization in the determination of systolic pulmonary artery pressure and diagnosis of pulmonary hypertension were investigated. The prevalence of pulmonary hypertension was 25% in the study population. Estimation of systolic pulmonary artery pressure by echocardiography was possible in 166 patients (44%). The correlation between systolic pulmonary artery pressure estimated by echocardiography and measured by cardiac catheterization was good (r = 0.69, p < 0.0001). However, 52% of pressure estimations were found to be inaccurate (more than 10 mm Hg difference compared with measured pressure), and 48% of patients were misclassified as having pulmonary hypertension by echocardiography. Sensitivity, specificity, and positive and negative predictive values of systolic pulmonary artery pressure estimation for diagnosis of pulmonary hypertension were 85%, 55%, 52%, and 87%, respectively. In conclusion, despite a statistically significant correlation with directly measured values, estimation of systolic pulmonary artery pressure by echocardiography is frequently inaccurate in patients with advanced lung disease and leads to considerable overdiagnosis of pulmonary hypertension.