Sudden death due to fibromuscular dysplasia of the sinoatrial nodal artery.

A case of sudden death is reported in a previously healthy 28-year-old female. No gross abnormalities of the heart or other organ systems were identified at autopsy. Routine microscopic sections of heart were unremarkable; however, sections of the cardiac conduction system revealed marked fibromuscular dysplasia of the sinoatrial node artery. The authors suggest that pathologists and clinicians index of suspicion be high when confronted with the enigma of sudden death in a patient with no apparent anatomic or toxicologic cause of death.