Circ Sildenafil in Pediatric Pulmonary Arterial Hypertension

"STARTS-2 Long-Term Survival With Oral Sildenafil Monotherapy in Treatment-Naive Pediatric Pulmonary Arterial Hypertension"  
http://circ.ahajournals.org/content/129/19/1914.abstract
"Conclusions—Although children randomized to higher compared with lower sildenafil doses had an unexplained increased mortality, all sildenafil dose groups displayed favorable survival for children with pulmonary arterial hypertension."