Sildenafil for Pulmonary Hypertension in Pregnancy?

Abstract

We thank Drs. Lynch and Laffey for their interest in our series of 15 cases of severe pulmonary arterial hypertension (PAH) during pregnancy and their useful comment on therapeutic options.1Our series gathered patients from 1992 to 2002. During this period, therapeutic options have expanded markedly and patient management has become more active. Nonetheless, even when considering our most recent cases only, pregnancy must be still discouraged undoubtedly. Therefore, therapeutic abortion is the first-line treatment we offer to patients who are pregnant already. In our experience, however, some patients decline this option. For these patients who are willing to continue with their pregnancy, it is particularly important to make sure that an updated optimal treatment is actually implemented. Although there is no curative treatment for idiopathic PAH, several drugs are now available to target the main dysfunctional pathways of the disease.These drugs included namely (1) prostaglandin I2(prostacyclin), (2) endothelin-1 receptor antagonists, and (3) type 5 phosphodiesterase inhibitors. According to our group2and to European3and American4guidelines, intravenous prostacyclin (epoprostenol) is the treatment of choice for patients with PAH in functional class IV. For patients with PAH in functional class III, endothelin-1 receptor antagonists or prostacyclin analogs (inhaled iloprost or subcutaneous treprostinil) may be used as an alternative. Guidelines do not provide specific recommendations in pregnant patients with regard to drug choice, except that the endothelin-1 receptor antagonist bosentan should be contraindicated.2,4This is because animal data indicate that bosentan could provide potential major birth defects.5,6Sildenafil is the first type 5 phosphodiesterase inhibitor approved for clinical use in the United States in patients with PAH, and it is currently in registration process in Europe (20 mg three times a day). As pointed out by Drs. Lynch and Laffey, it has several advantages over inhaled nitric oxide, and it is also particularly appealing for long-term treatment because of its oral administration, in contrast to other drugs. However, despite a few promising reports, more information is needed in pregnant patients with functional class III or IV PAH before it could be considered as a true alternative option to the above-mentioned guidelines. Meanwhile, we believe that prostacyclin therapy is a more validated approach.7Whatever the drug or combination of drugs chosen, it is important to report back both the positive and negative outcomes observed, because the experience remains (we hope) particularly scarce in this subpopulation of pregnant patients.*Antoine Beclere Hospital-Assistance Publique des Hôpitaux de Paris, France. frederic.mercier@abc.ap-hop-paris.fr