The effect of hematopoietic stem cell transplantation on cardiac mechanics in systemic sclerosis.

Systemic sclerosis (SSc) is an autoimmune disease that causes inflammation and fibrosis. Cardiac involvement in SSc is often subclinical and portends a worse prognosis. Autologous hematopoietic stem cell transplant (HSCT) improves survival in SSc but its effect on cardiac function is unknown. This study aimed to assess HSCT's effect on cardiac mechanics in SSc. Participants with SSc who received HSCT at a single academic center between 2009 and 2018 were identified from a prospective registry. All participants underwent comprehensive conventional and speckle-tracking echocardiography (STE) pre- and post-HSCT, and right heart catheterization before HSCT. Baseline and follow-up clinical and echocardiographic variables were compared. Among 88 HSCT recipients (age 51±11 years, 75% female), there was significant improvement of right ventricular (RV) strain globally (18.1±3.9% versus 20.0±4.5%, p < 0.01) and within the RV free wall (20.7±5.3% versus 23.2±5.6%, p < 0.01). Regionally, RV free wall strain improved in the mid (20.4±9.5% versus 23.7±8.0%, p = 0.04) and apical (15.3±8.6% versus 20.9±9.0%, p < 0.01) segments, but not the basal segment. While left ventricular (LV) strain did not change, left atrial (LA) reservoir strain improved (35.9±8.7% versus 47.8±11.4%, p < 0.01) and LA stiffness index (0.24±0.12 versus 0.18±0.08, p < 0.01) decreased post-HSCT. RV and LA mechanics significantly improve after HSCT among patients with SSc. This suggests a favorable effect of HSCT on the underlying myocardial pathology caused by SSc.