Answer: C. Wean the patient from the PDE-5 inhibitor and start epoprostenol and intravenous heparin.
Maternal mortality from PAH has decreased over the years, from 50% to 30% with earlier detection, multidisciplinary approaches to peripartum PAH therapy, and advances in medical therapy.1
Options A, B, and D are incorrect because endothelin receptor antagonists such as bosentan, ambrisentan, and macitentan are absolutely contraindicated during pregnancy (pregnancy category X). Experience with calcium channel blockers has been limited and vasodilatory testing should occur before pregnancy. Option E is not the best choice because the response to calcium channel blockers prior to pregnancy has not been established and there are more established treatments for PAH during pregnancy. Although option D is incorrect because of the bosentan, continuing the PDE-5 inhibitor is not unreasonable and in most developed countries, sildenafil is the drug of choice for PAH during pregnancy.1
Of the available options, option C is the most reasonable. Prostacyclins are the drug of choice for PAH over PDE-5 inhibitors at centers that treat patients at high risk because of improved exercise capacity, quality of life, hemodynamics, and long-term survival.1 Theoretic concerns about uterine blood flow with epoprostenol may have limited its use in the past, but more recent reports suggest that it can be used safely with good outcomes in both patients with PAH and those with Eisenmenger syndrome.1
All patients with PAH should receive anticoagulation therapy throughout pregnancy, particularly in the third trimester and postpartum period because of the markedly elevated risk for thromboembolism.1
Sahni S, Palkar AV, Rochelson BL, Kepa W, Talwar A. Pregnancy and pulmonary arterial hypertension: a clinical conundrum. Pregnancy Hypertens. 2015;5(2):157-164.