Abstract 4373041: Sotatercept-Enhanced Quadruple Therapy Reverses Hemodynamic Decline in Severe Systemic Lupus Erythematosus-Associated Pulmonary Arterial Hypertension

Background: Pulmonary arterial hypertension (PAH) is a rare but potentially fatal manifestation of systemic lupus erythematosus (SLE), occurring in a minority of patients and often presenting with nonspecific symptoms. We report a case of severe, biopsy-confirmed SLE with PAH as the presenting feature, showing significant reversal of disease following quadruple vasodilator therapy, including the novel agent sotatercept. Hypothesis: We hypothesized that combining immunosuppressive therapy with advanced pulmonary vasodilator strategies—specifically, sotatercept—could lead to significant hemodynamic and functional recovery in severe SLE-PAH. Methods: A 32-year-old male presented with NYHA class III symptoms including dyspnea, lower limb edema, and pleuritic chest discomfort. Echocardiography demonstrated an RVSP of 80 mmHg, and right heart catheterization revealed a mean pulmonary artery pressure (mPAP) of 40 mmHg, pulmonary vascular resistance (PVR) of 7 WU, and cardiac index of 2.56 L/min/m2. Laboratory evaluation confirmed active lupus nephritis, positive anti-dsDNA, low complement levels, and lupus anticoagulant positivity. Treatment included high-dose corticosteroids, mycophenolate mofetil, rituximab, tadalafil, macitentan, and continuous epoprostenol infusion. Sotatercept was introduced at month 5 due to persistent PAH. Results: By month 8, the patient's RVSP improved to 55 mmHg, PVR dropped to 4.1 WU, cardiac index increased to 3.5 L/min/m2, and NT-proBNP fell from 1500 pg/mL to <300 pg/mL. LVEF improved from 45–50% to 64%. The 6-minute walk distance increased from 200 to over 440 meters. Immunological markers normalized (ANA and anti-dsDNA turned negative; complements C3/C4 improved to 120/25 mg/dL). Lung transplantation was initially considered but later deferred due to sustained improvement. Conclusion: This case demonstrates that a proactive, multidisciplinary approach incorporating novel therapies such as sotatercept can reverse the trajectory of life-threatening SLE-PAH. Timely diagnosis, aggressive immunosuppression, and layered vasodilator regimens can restore cardiopulmonary function and delay or avoid transplantation in patients with advanced disease.