Systemic sclerosis (SSc) is a connective tissue disease marked by inflammation, microvascular abnormalities and fibrosis. Cardiac comorbidities are the leading cause of mortality. Early diagnosis of cardiovascular dysfunction remains difficult prior to clinical manifestations. Cardiovascular MRI (CMR) has emerged as a great noninvasive tool to assess cardiac impact in SSc patients. Hemodynamic forces (HDF) are a measurement of the global force exchanged between blood volume and myocardium assessed using CMR.

To assess the feasibility and diagnostic value of HDF measurement in SSc compared to healthy controls (HC), as a potential early indicator of subclinical cardiac dysfunction.

In a single-center study, patients with SSc who met the American college of rheumatology and European League against Rheumatism classification criteria were included and a 1.5T CMR exam was performed. HDF were obtained using an advanced post-processing software (Medis Suite, Leiden, Netherlands). Movements from deformation imaging of 2, 3, and 4-chamber cine were used for longitudinal (apical-basal – Fig. 1) and transversal (septal-lateral) left ventricle (LV) HDF calculation based on the Navier-Stokes equation. To compare different LV sizes, HDF were normalized, thus reported as percentage of gravity acceleration.

Of the 11 SSc patients (age 46.3±15.2 years, 19% male) recruited, 5 (46%) patients had a diffuse form and 5 (46%) patients had pulmonary hypertension. Two patients (18%) had LV systolic dysfunction with a mean LV ejection fraction (LVEF) of 59%. Five patients (46%) patients had right ventricle (RV) systolic dysfunction with a mean RVEF of 50%. We compared HDF in 11 SSc patients and in 11 age-matched healthy controls from an external cohort. SSc patients showed larger LV longitudinal HDF in systole (for RMS P=0.029, and for peak P=0.047), changes which could be explained by anatomical deformation caused by increased pressure in the RV. Diastolic deceleration was significantly lower in SSc (P=0.040), a finding that might indicate reduced LV compliance in the context of elevated LV filling pressures. Furthermore, the transverse to longitudinal ratio and the angle – elevated as compensatory mechanisms – were strongly correlated with the Rodnan score, a well-known clinical score for disease severity and prognosis.

HDF analysis has the potential to be a more sensitive marker of cardiac deterioration in SSc patients compared to traditional volumetric and functional parameters.