日本小児循環器学会雑誌 Pediatric Cardiology and Cardiac Surgery

A 4-year-old boy was diagnosed with idiopathic pulmonary arterial hypertension (IPAH) following edema and general fatigue. Despite the initiation of sildenafil (nitric oxide pathway drug) and Macitentan (endothelin pathway drug), pulmonary hypertension did not improve; thus, Selexipag, a drug that acts on the prostacyclin pathway, was added. However, its administration was discontinued due to chest pain. A positive acute pulmonary vasoreactivity test (AVT) with nitric oxide led to the introduction of a calcium channel blocker (CCB). After the CCB was introduced, selexipag was successfully reintroduced. Cardiac catheterization performed eight months after initiating treatment revealed remarkable improvement of the pulmonary arterial pressure and resistance. CCB efficacy has been reported in patients with IPAH having a positive AVT; however, there have been few reports on its efficacy in pediatric patients in Japan. We encountered a pediatric patient with IPAH who showed marked improvement with combination therapy, including CCB. Although CCB is not often administered for treating IPAH, it may be a useful option in some cases.