Influence of Left Ventricular Diastolic Function on Exercise-induced Pulmonary Hypertension in Patients with Systemic Sclerosis

Abstract

Background: Exercise-induced pulmonary hypertension (EIPH) can be caused not only by pulmonary vasculopathy, but also by a significant increase in left ventricular (LV) filling pressure. This study evaluated the influence of LV diastolic function on EIPH in patients with systemic sclerosis (SSc).
Methods: The study included 222 SSc patients (age 58.9 ± 13.1 years, 85% female) and 30 controls with similar age distribution. In all patients, systolic pulmonary artery pressure (SPAP) and the ratio of early diastolic transmitral flow velocity to early diastolic mitral annular velocity (E/e’), as an index of LV filling pressure, were measured before and after exercise Doppler echocardiography using a Master’s two-step.
Results: The patients with SSc were classified into either the non-EIPH (SPAP < 50 mmHg, n = 123, 56%) or EIPH (SPAP ≥ 50 mmHg, n = 97, 44%) group. No significant change from E/e’ at rest to E/e’ post exercise was found in the controls (8.8 and 9.6), whereas significant changes were found in the non-EIPH (8.7 and 9.5 p < 0.0001) and EIPH groups (10.3 and 12.6, p < 0.0001). In addition, significant differences in E/e’ at rest and post exercise were found between the non-EIPH and EIPH groups (p <0.0001). Multivariate logistic regression analysis identified age (odds ratio, 1.036; 95% confidence interval, 1.015–1.058, p < 0.0001) and E/e’ (odds ratio, 1.154; 95% confidence interval, 1.066–1.246, p < 0.0001) as independent predictors of EIPH.
Conclusions: Our results suggest that approximately one third of SSc patients have EIPH. LV diastolic function might be associated with EIPH in patients with SSc.