Certain congenital heart defects
Moyamoya syndrome is a complication of certain congenital heart defects. In patients who develop Moyamoya syndrome because of a congenital heart defect, there is a greater chance of stroke, transient neurologic deficit and seizure.
Understanding Moyamoya Disease
Moyamoya disease is a rare vascular disease of the brain, characterized by progressive blockage of the large branches of the internal carotid artery of the brain. To feed the starved cerebral tissue caused by Moyamoya disease, the body forms a network of dilated and weakened (friable) blood vessels. When viewed on a diagnostic cerebral angiography test, the blood vessels resemble a “puff of smoke.” This disease was originally identified in Japanese patients. Moyamoya is the Japanese word for the “puff of smoke” appearance.