Current outcomes of systemic-to-pulmonary artery shunt in patients with biventricular circulation

Objective: This study investigated the outcomes after systemic-to-pulmonary artery shunt in patients with biventricular circulation.

Methods: Between January 2014 and June 2023, among 406 patients who underwent systemic-to-pulmonary artery shunt implantation, 223 patients pursuing biventricular repair were included. The primary outcome of interest was a major adverse shunt-related event, which was defined as the composite of cardiopulmonary resuscitation, extracorporeal membrane oxygenation, and shunt-related intervention.

Results: The median age and body weight were 30 days and 3.5 kg, respectively. The median ratio of shunt diameter to body weight (mm/kg) was 1.0. The origin of systemic-to-pulmonary artery shunt was the subclavian artery in 118 patients (52.9%) and the innominate artery in 93 patients (41.7%). There were 4 early deaths (1.8%), all of which were preceded by an in-hospital major adverse shunt-related event resulting from pulmonary overcirculation. There were 2 interstage deaths (0.9%). Competing risk analysis showed that the probability of biventricular repair at 24 months after systemic-to-pulmonary artery shunt was 94.2%. An in-hospital major adverse shunt-related event occurred in 17 patients, with most cases (n = 14, 82.4%) resulting from pulmonary overcirculation. In multivariable analysis, associated genetic or extracardiac anomalies (odds ratio, 4.78; P = .019), transposition of the great arteries (odds ratio, 6.42; P = .012), and use of cardiopulmonary bypass (odds ratio, 7.39; P = .001) were identified as risk factors for in-hospital major adverse shunt-related events. Among 10 cases of interstage major adverse shunt-related events, 9 were successfully managed up to biventricular repair.

Conclusions: In the current era, the systemic-to-pulmonary artery shunt is a safe and useful option for patients with biventricular circulation. In patients with risk factors for in-hospital major adverse shunt-related events, meticulous efforts should be directed toward preventing pulmonary overcirculation to further enhance outcomes.