Congenital absence of the left atrial appendage.

The article describes the congenital absence of the left atrial appendage (LAA) in a three-month-old male child. Highlights include three reports suggesting ostium secundum atrial septal defect and large muscular ventricular septal defect in a setting of transposition of great arteries, the patient's death related to adenoviral interstitial pneumonitis, and three possibilities of the absence of the LAA at its normal anatomical location.