Contribution of Speckle Tracking to Estimation of Pulmonary Hypertension by Standard Doppler Echocardiography in Patients with Systemic Sclerosis and MCTD

Abstract

Objectives: Development of pulmonary arterial hypertension (PAH) in systemic sclerosis (SSc) represents one of the most serious complications. The study aimed at assessing right ventricular (RV) global longitudinal strain and its relation to pulmonary artery pressure. Methods: Echocardiography was performed in 74 patients of whom 60 had SSc and 14 had mixed connective tissue disease (MCTD). Besides routine left and right ventricle assessment and pulmonary pressure estimation by Doppler echocardiography, RV fractional area change (FAC) and 2D strain of the RV free wall were evaluated. At the same time, levels of N-terminal pro-brain natriuretic peptide (NT-proBNP), troponin T and auto-antibodies were measured and all patients had diffusing capacity of the lung for carbon monoxide (DLCO) determined. All patients with probable PAH underwent right heart catheterization. Results: Pulmonary hypertension was found to be unlikely in 59 patients (79.7%), possible in 10 patients (13.5%) and probable in 5 patients (6.7%). Significant associations were found between pulmonary artery systolic pressure (PASP) and RV free wall global longitudinal strain (r=0.292; p=0.023), between PASP and NT-proBNP (r=0.436; p=0.001) and between PASP and FAC (r=0.320; p=0.005). Pulmonary artery systolic pressure did not correlate with left ventricular systolic or diastolic function parameters in this cohort. Conclusion: Speckle tracking of the RV represents a useful additional tool in RV assessment in relation to PH in SSc and MCTD patients; right heart catheterization remains an essential method for PAH confirmation.