Atrial septostomy, earlier arterial switch operations linked to improved survival

A new study published in Circulation emphasized the importance of prompt arterial switch operations (ASOs) for infants with transposition of the great arteries, as neonates more than 6 days old were 90 percent more likely to die in the perioperative period.

The overall mortality rate was relatively low (2.8 percent), but the retrospective research identified age at operation and the use of balloon atrial septostomy as independently associated with perioperative mortality. Infants who received septostomy were 68 percent less likely to die and experienced shorter hospital stays with lower costs.

“Perioperative care should continue to be individualized on the basis of patient anatomy and physiology, although the potential risks of delaying ASO should be carefully considered, as should the potential benefit of septostomy,” wrote lead author Michael L. O’Byrne, MD, with Children’s Hospital of Philadelphia, and colleagues. “At the hospital level, these findings should be considered in organizing preoperative care of infants with transposition of the great arteries, prioritizing efficient evaluation and treatment of patients before ASO.”

O’Byrne et al. analyzed aspects of care and in-hospital outcomes for 2,159 neonates undergoing ASO at 40 facilities from 2010 through September 2015. They noted ASO is a gold standard treatment for correcting transposition of the great arteries (TGA) “with excellent operative survival,” but there has been little research into variation in perioperative care and its association with outcomes.

Even though the study utilized the Pediatric Health Information Systems database—which contains many large, academic centers—the authors found significant between-hospital variation in care processes. For example, the median age at ASO between centers varied from day 3 to beyond day 10.

At the hospital level, each one-day increase for the median time of ASO was associated with 15 percent higher odds of mortality. The only other hospital characteristic independently associated with mortality was annual cardiothoracic surgical volume, with more procedures being linked to a lower risk of mortality.

“The observed associations point to potentially modifiable aspects of care that could improve outcomes and value delivered to patients with TGA,” O’Byrne and coauthors wrote. “Further research is necessary to determine whether the benefit of early ASO is directly related to timing (as a result of reduced exposure to cyanosis and risk of iatrogenic events) or whether earlier ASO at individual hospitals is an indicator of hospital surgical program quality. Differentiating between these factors is an important step in determining how to translate these observations into practice.”

The researchers noted there aren’t currently any guidelines on ASO timing or when balloon atrial septostomy should be considered. They said this was part of the motivation for their study and may explain the wide range of between-hospital variation they observed, which couldn’t be explained by differences in case mix.