B64-28 A Rare Case of Severe Chronic Thromboembolic Pulmonary Hypertension in a Young Male With Dextrocardia

Abstract Introduction Chronic thromboembolic pulmonary hypertension (CTEPH) is a rare yet potentially curable cause of pulmonary hypertension (PH) resulting from unresolved pulmonary emboli that lead to persistent vascular obstruction and right heart failure. Diagnosis can be delayed due to its nonspecific symptoms and overlap with other cardiopulmonary disorders. The presence of congenital anomalies such as dextrocardia further complicates the diagnostic and therapeutic approach. We present a case of severe precapillary PH secondary to CTEPH in a patient with dextrocardia and congenital gut malrotation, highlighting the clinical, hemodynamic, and therapeutic complexities involved. Case Description A 40-year-old male with a medical history significant for dextrocardia, congenital gut malrotation, hypertension, chronic right lower extremity deep vein thrombosis, chronic lymphedema, and unprovoked bilateral pulmonary emboli (2022) presented with progressive dyspnea, exertional cough, dizziness, and limited exercise tolerance. He had discontinued anticoagulation one year prior due to insurance constraints. Right heart catheterization demonstrated markedly elevated pulmonary artery pressures (92/34/57 mmHg), pulmonary capillary wedge pressure of 7 mmHg, and elevated pulmonary vascular resistance (11.8 Wood units), consistent with severe precapillary PH. Transthoracic echocardiography revealed severe right atrial and right ventricular dilation, moderate right ventricular systolic dysfunction, septal bowing, and a moderate pericardial effusion. He was transferred to the cardiac care unit for Swan-Ganz catheter monitoring, aggressive diuresis, and initiation of targeted pulmonary arterial hypertension therapy. Riociguat (1.5 mg three times daily, titrated to 2 mg) was started for CTEPH, along with midodrine for blood pressure support and resumption of anticoagulation with rivaroxaban. A ventilation-perfusion scan was ordered for surgical evaluation for pulmonary thromboendarterectomy, and hypercoagulable workup was initiated. The patient required supplemental oxygen and was discharged on home oxygen therapy. On follow-up, he demonstrated symptomatic improvement, reduced BNP, and improved hemodynamic stability. Discussion This case underscores the challenges of managing severe PH in a patient with complex congenital anatomy. The coexistence of dextrocardia and CTEPH required careful imaging interpretation, precise hemodynamic assessment, and tailored therapy. It also highlights the consequences of treatment interruption due to healthcare access barriers. CTEPH remains the only potentially curable form of PH via pulmonary thromboendarterectomy, and early initiation of Riociguat provides hemodynamic stabilization and symptomatic benefit. This case emphasizes the importance of multidisciplinary coordination, timely diagnosis, and sustained access to anticoagulation in improving outcomes for patients with advanced pulmonary vascular disease. This abstract is funded by: None