Papillary muscle necrosis in a neonatal autopsy population: incidence and associated clinical manifestations.

Papillary muscle necrosis was found in 24 of 84 neonates without congenital heart disease who died and were autopsied during a 17-month study period. The lesion was most prevalent in infants greater than or equal to 3,000 gm birth weight (59%), but papillary muscle necrosis was also noted in 25% of the infants of medium birth weight (1,500 to 2,999 gm) and in 19% of the very low-birth-weight infants (less than 1,500 gm). Papillary muscle necrosis in the highest birth-weight group correlated with five-minute Apgar scores of 6 or less, meconium aspiration syndrome, seizures, congestive heart failure, increased cardiothoracic ratio (greater than or equal to 0.60), and ischemic changes on electrocardiogram. In the medium- and very low-birth-weight groups, however, patients with papillary muscle necrosis could seldom be differentiated clinically from their birth-weight peers without the lesion, even in retrospect.