Inhaled Iloprost for Chronic Thromboembolic Pulmonary Hypertension (CTEPH) During Pregnancy: A Case Report

Chronic thromboembolic pulmonary hypertension (CTEPH) is a subset of pulmonary hypertension caused by acute and recurrent pulmonary emboli. Pulmonary thromboendarterectomy is the treatment of choice, but 10-50% of patients are ineligible for this procedure. We describe the case of a 25-year-old, morbidly obese (228-kg, body mass index 83.5 kg/m(2) ) pregnant woman (G3 P2 ) who presented at 24 weeks' gestation; bilateral pulmonary angiography revealed filling defects and confirmed the diagnosis of CTEPH. The patient was evaluated and deemed to present too high of a risk for pulmonary thromboendarterectomy, so a multidisciplinary team initiated medical therapy. Sildenafil 20 mg orally 3 times/day was started at week 24 of gestation, and inhaled iloprost was added at 26 weeks and titrated to 5 µg inhaled every 2 hrs in order to optimize hemodynamic status prior to a cesarean section delivery scheduled to be performed 6 weeks later. At 32 weeks of gestation, the patient's pulmonary arterial systolic pressure was 77 mm Hg, right atrial pressure was 15 mm Hg, and pulmonary capillary wedge pressure of 16 mm Hg, and a healthy 1741-g male infant was delivered by cesarean section. The patient was transferred back to the medical intensive care unit in stable condition and discharged home 9 days following the procedure. Pharmacotherapeutic strategies for patients with CTEPH who become pregnant are limited to phosphodiesterase type 5 inhibitors and prostacyclin analog therapies due to the teratogenicity of the other drug classes used to treat the disorder (endothelin receptor antagonists and soluble guanylate cyclase stimulators). To our knowledge, this is the first case report of inhaled iloprost use in addition to oral sildenafil to improve patient symptomatology and hemodynamics during the peripartum period of a young pregnant patient with inoperable CTEPH. This drug therapy was used safely, with no noted adverse effects to the newborn or to the patient.