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 (SPS) in patients with biventricular circulation.

Methods: Between January 2014 and June 2023, among 406 patients who underwent SPS, 223 patients pursuing biventricular repair were included. Primary outcome of interest was major adverse shunt-related event (MASE) 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. Median ratio of shunt diameter to body weight (mm/kg) was 1.0. The origin of SPS was the subclavian artery in 118 (52.9%), and the innominate artery in 93 patients (41.7%). There were 4 early deaths (1.8%), all of which were preceded by in-hospital MASE resulting from pulmonary overcirculation. There were two interstage deaths (0.9%). Competing risk analysis showed that the probability of biventricular repair at 24 months after SPS was 94.2%. In-hospital MASE 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 [OR] 4.78; p=0.019), transposition of the great arteries (OR 6.42; p=0.012) and use of cardiopulmonary bypass (OR 7.39; p=0.001) were identified as risk factors for in-hospital MASE. Among 10 cases of inter-stage MASE, 9 cases were successfully managed up to biventricular repair.

Conclusions: In the current era, SPS is a safe and useful option for patients with biventricular circulation. In patients with risk factors for in-hospital MASE, meticulous efforts should be directed towards preventing pulmonary overcirculation to further enhance outcomes.