Interim mortality in infants with systemic-to-pulmonary artery shunts

This retrospective review examines the risks and causes of death in infants with aortopulmonary shunts between the time of hospital discharge and planned reintervention.

From January 1991 through December 2000, a total of 146 infants aged 60 days or less underwent placement of systemic-to-pulmonary artery shunts and were discharged from the hospital alive. Inpatient, outpatient, and autopsy records were reviewed.

Indications for surgery were single-ventricle anatomy in 90 cases and complex double-ventricle anatomy in 56. Of the patients, 21 (14%) died after discharge and before further planned surgery. Of these 21 infants, 17 (81%) were clinically doing well before sudden death. Autopsies were obtained in 15 cases and attributed the cause of death to shunt thrombosis in 5 infants (33%), myocardial infarction in 2 (13%), and pneumonia or lung disease in 3. Five autopsies were nondiagnostic. The mortality of patients discharged on aspirin (11.1%) was almost identical to that of patients discharged on no anticoagulation (12.3%). Four infants with sudden death had been notably irritable for 24 to 48 hours before death.

There is a significant incidence of sudden death among infants who have undergone shunting. Death may be preceded by unexplained irritability, and such symptoms should therefore be carefully evaluated. Autopsy-proven shunt thrombosis is one of the leading causes of interim sudden death, and aspirin therapy may not be helpful. Options to reduce interim mortality include alternative regimens of anticoagulation (such as low-molecular weight heparin), alternative conduit material, and earlier reoperation.