Variation in Atrial Fibrillation Ablation Strategies and Demographic Characteristics According to Comorbidity Status: A Descriptive Analysis from the VARY Registry

Background: Atrial fibrillation (AF) is a common arrhythmia with increasing prevalence in aging and multimorbid populations. Catheter ablation is a cornerstone of rhythm control, but there is a paucity of real-world national healthcare data in Germany.

Objective: To descriptively compare ablation strategies and patient characteristics across major comorbidity groups undergoing AF ablation in Germany.

Methods: This retrospective multicenter study analyzed 20,437 inpatient AF ablation cases from the German VARY registry. According to the German law German hospitals are obliged to provide a dataset including case data, diagnosis based on the ICD-10-GM, operational and procedural codes to the Institute for hospital remuneration system (InEK) every year. The VARY project aims at analyzing and monitoring these data to report the real-world scenario on patients undergoing catheter ablation in Germany. Until date 12 German centers contributed to the request of the Institute for Myocardial Infarction Research (IHF). Their Data between 2013 and 2018 provided from 12 of those centers were used for this analysis

Patients were stratified by ICD-10 codes into four mutually exclusive groups: chronic kidney disease (CKD), diabetes mellitus (DM), hypertension (HTN), and no comorbidities. Demographic characteristics, procedural strategies (energy modalities, anatomical targets, and adjunctive technologies), as well as hospitalization parameters (length of stay, ICU treatment, ventilation), discharge types, and comorbid diagnoses (including cardiovascular and arrhythmic conditions) were compared using descriptive statistics.

Results: CKD and DM patients were older (mean 71.7 and 67.6 years) and had higher rates of elderly individuals (≥65 years: 80.3% and 64.8%) compared to the control group (mean age 60,3 years and elderly group: 38.0%). Cooled radiofrequency (RF) ablation was used more frequently in CKD (56.6%) and DM (52.4%) groups, while cryoablation dominated in patients without comorbidities (49.2%). Isolated pulmonary vein isolation was more common in controls (79.3%), whereas multi-site target areas were less frequent in CDK compared to the other three groups. Electroanatomical mapping and contact force monitoring were used more often in comorbid groups – especially in the CKD group. Hospital stay, ICU utilization, and cardiovascular comorbidities also varied significantly across the groups, reflecting broader clinical differences beyond the ablation procedure itself.

Conclusion: Patients with AF and major comorbidities undergo more complex and individualized ablation strategies in routine care. These findings suggest that clinical practice already incorporates substrate-related risk profiles into procedural planning. Future prospective studies are warranted to assess the impact of these adaptations on outcomes and long-term rhythm control.