Disease Activity Is Related to Acute Response to Vasodilator in Pulmonary Artery Hypertension Associated With Systemic Lupus Erythematosus

BACKGROUND: No previous study has been done on whether systemic lupus erythematosus (SLE) disease activity is related to the hemodynamics and right ventricular (RV) function in patients with SLE-associated pulmonary artery hypertension (SLE-APAH). METHODS AND RESULTS: This study prospectively recruited 54 patients (mean age, 32.8±8.4 years; 92.6% female) with SLE-APAH, including 34 patients with SLE disease activity index (SLEDAI) <5 (low score) and 20 with SLEDAI ≥5 (high score). All patients underwent right heart catheterization and iloprost inhalation, and echocardiography was performed before and immediately after iloprost inhalation. There was no difference in baseline mean pulmonary artery pressure (mPAP) between the 2 groups; pulmonary vascular resistance (PVR) was significantly higher and cardiac index was significantly lower in the low-SLEDAI group. The patients with low SLEDAI had larger RV size and worse RV systolic function on echocardiography. After iloprost inhalation, the patients with low SLEDAI had a greater decrease in mPAP and PVR than those with high SLEDAI, while significantly increased RV systolic function was found only in the low-SLEDAI group. CONCLUSIONS: SLE activity is related to hemodynamics and RV function in SLE-APAH patients, and those with low SLEDAI might have better acute response to vasodilator inhalation.