Major In-Hospital Complications after Catheter Ablation of Cardiac Arrhythmias - Individual Case Analysis of 43,031 Procedures

Objective and Background In-hospital complications of catheter ablation for atrial fibrillation (AF), atrial flutter (AFL), and ventricular tachycardia (VT) may be overestimated by analyses of administrative data. Methods We determined the incidences of in-hospital mortality, major bleeding, and stroke around AF, AFL, and VT ablations in four German tertiary centers between 2005-2020. All cases were coded by the G-DRG- and OPS-systems. Uniform code search terms were applied defining both the types of ablations for AF, AFL, and VT and the occurrence of major adverse events including femoral vascular complications, iatrogenic tamponade, stroke, and in-hospital death. Importantly, all complications were individually reviewed based on patient-level source records. Results Overall, 43,031 ablations were analyzed (30,361 AF; 9,364 AFL; 3,306 VT). The number of ablations/year more than doubled from 2005 (n=1569) to 2020 (n=3317) with 3 times and 2.5 times more AF and VT ablations in 2020 (n=2404 and n=301, resp.) as compared to 2005 (n=817 and n=120, resp.), but a rather stable number of AFL ablations (n=554 vs. n=612). Major periprocedural complications occurred in 594 (1.4%) patients. Complication rates were 1.1% (n=325) for AF, 1.0% (n=95) for AFL, and 5.3% (n=175) for VT. With an increase in complex AF/VT procedures the overall complication rate significantly increased (0.76% in 2005 vs. 1.81% in 2020; p=0.004). but remained low over time. Following patient-adjudication, all in-hospital cardiac tamponades (0.7%) and strokes (0.2%) were related to ablation. Major femoral vascular complications requiring surgical intervention occurred in 0.4% of all patients. The in-hospital mortality rate adjudicated to be ablation-related was lower than the coded mortality rate: AF: 0.03% vs. 0.04%; AFL: 0.04% vs. 0.14%; VT: 0.42% vs. 1.48%. Conclusion Major adverse events are low and comparable after catheter ablation for AFL and AF (around 1.0%), whereas they are five times higher for VT ablations. In the presence of an increase in complex ablations procedures a moderate but significant increase in overall complications from 2005-2020 was observed. Individual case analysis demonstrated a lower than coded ablation-related in-hospital mortality. This highlights the importance of individual case adjudication when analyzing administrative data.