Subanalysis of transcatheter secundum ASD closure under local anaesthesia with transthoracic echocardiography and fluoroscopy: success, early complications and predictors

Background/Introduction Transcatheter closure of secundum atrial septal defect (ASD) is commonly performed under general anaesthesia with transoesophageal echocardiography. Local anaesthesia with transthoracic echocardiography (TTE) may reduce resource use while maintaining procedural safety; robust large-cohort data remain limited. Purpose To evaluate procedural success and 24-hour safety of ASD device closure under local anaesthesia with TTE and fluoroscopy, and to perform a prespecified subanalysis of outcomes by age, defect size and time period (learning curve), including predictors of major complications. Methods In a retrospective single-centre cohort, consecutive patients undergoing transcatheter secundum ASD closure under local anaesthesia between November 2008 and May 2024 were analysed. Procedures were guided by TTE and fluoroscopy with optional balloon sizing. The primary endpoint was procedural success at 24 hours (successful device implantation with no clinically significant residual shunt by colour Doppler). Secondary endpoints included immediate success, major complications within 24 hours, and procedural parameters. Subgroup analyses were performed by age (<18, 18–40, >40 years), ASD size (<20, 20–30, >30 mm), and time period (2008–2012, 2013–2018, 2019–2024). Multivariable analysis assessed predictors of major complications. Results A total of 856 patients were included (68.2% female; mean age 28.4±16.7 years; range 3–78). Immediate success was 97.7% (836/856; 95% CI 96.8–98.6) and 24-hour success was 96.9% (830/856; 95% CI 95.9–97.9). Mean procedure time was 45±15 minutes and fluoroscopy time 12±8 minutes. Major complications occurred in 2.9% (25/856), including device embolisation (0.9%), significant vascular complications (1.4%), emergency surgery (0.4%), stroke (0.1%) and complete atrioventricular block (0.1%); there was no procedural mortality. Subanalysis showed similar success across age groups (p=0.48) and ASD size groups (p=0.61). A significant learning-curve effect was observed with increasing success from 95.8% (2008–2012) to 98.4% (2019–2024) (p=0.003). Independent predictors of major complications were ASD diameter >25 mm (OR 2.8, 95% CI 1.4–5.6), age >60 years (OR 2.1, 95% CI 1.1–4.2) and deficient aortic rim <4 mm (OR 1.9, 95% CI 1.0–3.7). Conclusion(s) In this large cohort, transcatheter secundum ASD closure under local anaesthesia with TTE and fluoroscopic guidance achieved high early success with low 24-hour major complication rates. Subanalysis suggests stable performance across age and defect-size strata, improvement over time consistent with a learning curve, and identifies anatomic and clinical predictors that may refine patient selection and procedural planning.