[Preoperative mortality in transposition of the great vessels]

The aim of the study was to report the incidence and causes of preoperative deaths in isolated transposition of the great vessels and to describe the clinical findings in these neonates.

In five French centers of pediatric cardiology, data of all the neonates with isolated transposition of the great vessels who died before arterial switch operations between January 1986 and June 1996 were obtained from reviewing hospital files, echocardiography records and autopsy reports.

Among 199 neonates with transposition of the great vessels, 20 (9.9%) died before surgery. The death was related to intracranial haemorrhage in one premature neonate, severe and early hypoxemia in 13 full-term patients (group A) and later sudden collapse in six patients (group B). In group A, the symptoms occurred within 20 minutes after the birth and included cyanosis (n = 12), acute respiratory distress (n = 8), and shock (n = 4). Despite assisted ventilation (n = 13), bicarbonate infusion (n = 12), prostaglandin E1 (n = 7), inotropic drugs (n = 5) and balloon atrioseptostomy (n = 7), death occurred at the median age of five hours. The patent foramen ovale was absent or tiny in ten patients, normal in one patient and not specified in two patients. The ductus arteriosus was patent in ten patients and not specified in three patients. In group B, the neonates were initially in a good hemodynamic condition. Unexplained death occurred between two and five days after the birth: one infant with a large patent foramen ovale did not receive prostaglandin E1, four patients died a few hours after an angiographic study or a balloon atrioseptostomy was performed in a catheterization laboratory, and one child suffered from a cerebral anoxia due to a tightened cord.

We conclude that the high preoperative mortality rate in isolated transposition of the great vessels is mainly due to absent or small atrial shunt. These findings suggest that only prenatal diagnosis of transposition of the great vessels with immediate balloon atrioseptostomy could avoid a fatal outcome.