Echocardiographic Screening for Pulmonary Hypertension in Stable COPD Out-Patients and NT-proBNP as a Rule-Out Test

Abstract

Pulmonary hypertension (PH) worsens the prognosis in chronic obstructive pulmonary disease (COPD). The diagnosis of PH is established by right heart catheterisation (RHC), while echocardiography can be used for screening. We aimed to asses the outcome of echocardiographic screening for PH in a group of stable COPD out-patients, and to evaluate NT-proBNP as a first line screening tool. Criteria for PH on echocardiography were a tricuspid regurgitation pressure gradient > 40 mmHg, a tricuspid annular plane systolic excursion < 1.8 cm or right ventricular dilatation. Positively screened patients were asked to undergo RHC. Results (Mean ± SEM): 16 of 117 patients (14%) had PH on echocardiography. They had a higher mortality (hazard ratio for death: 2.7 ± 1.3, p = 0.037) and lower six minute walk test (224 ± 33 vs. 339 ± 15, p = 0.006). NT-proBNP below 95 ng/l excluded PH on echocardiography with a negative predictive value of 100 (95% CI: 89–100%). RHC was obtained in six patients screened positive. In three of these, PH was not confirmed. Conclusions: Signs of PH on echocardiography as defined here was found in 14% and had prognostic significance in COPD. A value of NT-proBNP less than 95 ng/l may be used to exclude signs of PH.

Keywords :

• biomarkers
• BNP
• chronic lung disease
• mortality
• 6-six minute walk test.