Safe treatment of pulmonary hypertension with bosentan in a patient with moyamoya disease and cerebral ischemia.

A 7-year-old girl with Down syndrome and moderately severe pulmonary hypertension experienced a stroke while being treated with a calcium channel blocker. Angiography identified bilateral stenosis of the supraclinoid internal carotid arteries, stenosis or occlusion of the proximal anterior and middle cerebral arteries, and occlusion of the left posterior cerebral artery. She underwent surgery to enhance collateral blood flow to vulnerable areas of the brain. Her pulmonary hypertension therapy was changed to an oral endothelin receptor antagonist. She developed excellent collateral blood flow through external carotid arteries to each cerebral hemisphere and an improvement in blood flow through the right internal carotid artery. This case suggests that bosentan can be used safely in children with moyamoya disease. Additional studies are needed to determine whether endothelin receptor antagonists may influence the progression of moyamoya disease or the development of collateral cerebral blood flow following surgery.