Operator Experience and Outcomes after Transcatheter Left Atrial Appendage Occlusion with the Watchman Device

Transcatheter left atrial appendage occlusion (LAAO) has become a suitable alternative to anticoagulation in patients with atrial fibrillation (AF). However, volume-outcome relationships at the individual operator level have not been studied.

Study population included 425 consecutive patients with AF undergoing LAAO from August 2015 to November 2018 by seven operators at BUMC-Phoenix. Operator volume was divided in tertiles by those with <40 cases/year (2 operators), 41-80 cases/year (3 operators) and >80 cases/year (2 operators). Patient data including comorbidities, labs, medications, procedural characteristics and outcomes were collected. The primary composite outcome was major adverse cardiac events (MACE) including mortality, stroke, bleeding and vascular complications.

Mean age was 75 ± 8 years and 251 (59%) were males. Mean CHA2DS2-VASc score was 4.5 ± 1.3 points and mean HASBLED score was 3.9 ± 1.0 points. MACE outcome was similar in the three operator groups in both unadjusted (p = 0.83) and adjusted (OR = 0.59: 95% Confidence Interval [CI]: 0.15-2.29, p = 0.45) analysis. The occurrence MACE was also similar between Interventional Cardiologist (IC) and Electrophysiologist (EP) operators in an unadjusted (p = 0.24) and adjusted (OR = 0.60: 95% CI: 0.21-1.68, p = 0.33) analysis. The secondary outcome of technical success did not differ among the three tertiles (p = 0.37) and among IC & EP operators respectively (p = 0.24) as well.

Operator experience does not affect MACE and technical success even after adjusting for comorbidities. These results suggest a lower learning curve for LAAO with high technical success achievable even by low volume operators.