Transcatheter patent ductus arteriosus (PDA) closure is safe in < 2 kg infants and in ≥ 6 kg patients, but major safety concerns remain when applied to the intermediate weight range. We aimed to assess outcomes of transcatheter PDA closure in 2 to 6 kg infants.

An international, multicentre, retrospective cohort study was conducted in 31 tertiary hospitals in 17 countries between 2000 and 2023, investigating all infants who underwent attempted transcatheter PDA closure with a procedural weight of 2 to 6 kg.

Attempted transcatheter PDA closure was performed in 1231 infants (median weight: 4747 grams Q1–Q3 [3700–5300]; median age: 132 days Q1–Q3 [83–194]; ex-preterm: n = 581 [56.8%]) with a 95.0% success rate. A composite outcome of procedural failure or major adverse events was observed in 173 (14%) patients, including device embolization in 64 (3.7%), device-induced left pulmonary artery stenosis in 47 (2.7%) and procedural death in 2 (0.2%). Logistic regression model analysis identified a 2-to 3.9-kg procedural weight, increased pulmonary artery pressure, and window-type or tubular ductal morphologies as independent predictors of the composite outcome. Based on propensity score matching analysis, 2 to 3.9 kg infants had a risk ratio of 2.19 (95%CI, 1.25–3.83) for experiencing the composite outcome, as compared to 4 to 5.9 kg infants.

Transcatheter PDA closure in 2 to 6 kg infants was feasible in most patients. Procedural failure or major adverse events occurred in 14% and several independent risk factors were identified, including the 2 to 3.9 kg weight range identified as a higher-risk subgroup. These findings may improve risk stratification and decision-making process.