Sudden Infant and Early Childhood Death and Sinus of Valsalva Pseudoaneurysms.

Two cases of occult pseudoaneurysms of the sinus of Valsalva (SoV) are reported to demonstrate different etiologies and lethal mechanisms. A previously well 9-month-old boy who suffered an unexpected fatal cardiorespiratory arrest was found at autopsy to have a ruptured pseudoaneurysm of the left SoV resulting in lethal hemopericardium. A 13.5-month-old boy died soon after presenting with a 24-h history of poor feeding and reduced urine output. At autopsy, destruction of the noncoronary cusp of the aortic valve by bacterial endocarditis was found with extension of the inflammation into a pseudoaneurysm of the SoV with surrounding abscess formation involving the atrioventricular node. Death was most likely due to an arrhythmia. Pseudoaneurysms of the SoV are exceedingly rare but may result in sudden/unexpected death in infancy and early childhood from rupture or involvement of the conduction system or myocardium. Detailed cardiac examination is essential in all unexpected deaths in early life.