Introduction: The Barts Heart Centre was established in May 2015. Trends in EP procedural workflow and complications were examined as part of continuous audit.
Methods: Procedural data were extracted from an internal database of all electrophysiology procedures (EP studies and ablations) performed between 1st January 2016 and 1st January 2020. Procedure reports and clinical records were examined for patient parameters, intraprocedural variables, and the incidence of acute and long-term complications.
Results: 23 consultant operators performed 5,514 procedures of which 1,278 (23%) were re-do procedures. Procedural output was as follows: Left atrial ablation (n=2,762, 50%), typical flutter (n=908, 17%), AVNRT/AVRT (n=701, 13%), diagnostic EP study (n=467, 8%), VT (n=422, 8%), AV node (n=252, 4%). There were 159 complications (2.88%) with a non-significant increase in complications over time (2016: 2.42%, 2017: 2.82%, 2018: 3.1%, 2019: 3.32%, p=0.28). The most frequent complications were cardiac tamponade (n=78, 1.4%), vascular access (n=23, 0.4%), phrenic nerve injury (temporary or permanent; n=13, 0.2%) and unintended AV block requiring pacing (n=7, 0.13%). 3 patients (0.05%) died during, or as a result of complications from, the procedure, and a further 6 (0.1%) died in hospital within 30 days of the procedure from congestive cardiac failure.
Multivariate logistic regression analysis identified the following significant predictors of complications – patient parameters: age (OR 1.03 (1.01-1.04), p<0.001); ischaemic heart disease (OR 2.37 (1.5-3.7), p<0.001); procedure type: any re-do procedure (OR 1.57 (1.32-2.14), p=0.003); VT ablation (OR 3.97 (2.29-6.87); p<0.001); re-do AF ablation (OR 1.87 (1.13-3.09), p=0.015); and intraprocedural variables: transseptal puncture performed (OR 1.56 (1.04-2.36), p=0.026); epicardial access (OR 2.2 (1.05-4.82) p=0.032); procedure time of over 2 hours (OR 1.46 (1.06-2.03), p=0.022). Emergency presentation (OR 1.03, (0.4-2.68), p=0.95), congenital heart disease (OR 0.66 (0.26-1.70), p=0.37) or zero fluoroscopy use (OR 0.56 (0.29-1.07), p=0.062) were not associated with an increased risk of complications. Variation in complication rates between operators (range 0.81-5.1%) became non-significant when adjusting for procedural complexity and patient demographics.
Conclusions: Ablation complication rates across a broad range of procedures at a high-volume EP centre are low and similar between operators when adjusting for procedural risk. Important predictors of complications have been identified which will be incorporated into future clinical decision making and consent. Prospective validation of a pre-procedural risk score is ongoing.