Decreased biventricular longitudinal strain in patients with systemic sclerosis is mainly caused by pulmonary hypertension and not by systemic sclerosis per se.

PURPOSE: Patients with pulmonary arterial hypertension (PAH) due to systemic sclerosis (SSc) have high mortality. Left ventricular (LV) peak global longitudinal strain (GLS) is decreased in SSc. It is unknown if low GLS is due to SSc or PAH. Therefore, our primary aim was to evaluate both LV and RV free wall GLS (RVRF GLS) in SSc, with and without PAH, using cardiac magnetic resonance with feature tracking. Secondary aim was to relate GLS to invasive mean pulmonary arterial pressure (mPAP) and pulmonary vascular resistance (PVR).

METHODS: Thirty-eight patients with SSc, 19 patients with SSc-PAH and 19 healthy controls for comparison, were included. Endocardial and epicardial borders were delineated in cine images (short axis stack and three long axis views) for volumetric and strain calculations.

RESULTS: SSc-PAH had lower LV and RVFW GLS than SSc (LV: p=0·01, RV: p<0·001) and controls (LV: p=0·02; RV: p<0·001), with no difference between SSc and controls. LV strain correlated with mPAP (R=0·42, p=0·03) and PVR (R=0·52, p=0·006). RV free wall GLS correlated with mPAP (R=0·68, p<0·001) and PVR (R=0·59, p=0·001). ROC curves for predicting PAH had AUC 0·73 for LV strain (p=0·003) and 0·86 for RV free wall GLS (p<0·001).

CONCLUSIONS: Lower GLS is mainly determined by increased pulmonary pressure and not by SSc per se. Low LV and RVFW GLS is indicative of increased mPAP and PVR, which opens for improved non-invasive methods to select patients eligible for right heart catheterization and to monitor effects of PAH therapy. This article is protected by copyright. All rights reserved.