Catheter Ablation After IBD Carries a Higher Burden of Arrhythmia-Related Events
Patients with inflammatory bowel disease who underwent catheter ablation for arrhythmia faced a higher risk of adverse rhythm-related outcomes than matched patients without IBD in a nationwide Swiss cohort. Over a median follow-up of 2.6 years, the composite endpoint of reablation, cardioversion, or hospitalization for arrhythmia occurred more often in the IBD group, with the excess driven by hospital admissions for arrhythmia rather than by the procedural endpoints themselves.
The finding is clinically important because ablation is typically pursued to reduce recurrent arrhythmia burden, decrease symptoms, and limit repeat acute care use. In this cohort, the antiarrhythmic strategy did not fully erase the downstream instability associated with IBD. The signal suggests that the inflammatory milieu, comorbidity profile, or treatment complexity that accompanies IBD may continue to shape rhythm outcomes even after an apparently definitive electrophysiologic intervention.
What the Swiss Cohort Measured
Investigators assembled adults who underwent catheter ablation for arrhythmia between 2012 and 2022 and identified 251 patients with IBD. These patients were propensity score-matched 1:10 to 2429 comparators without IBD. The design narrowed confounding by balancing observable baseline characteristics, allowing the post-ablation course to be compared more cleanly between groups.
The primary endpoint was a composite of first occurrence of reablation, cardioversion, or hospitalization for arrhythmia. Secondary analyses examined each component separately, and a hierarchical win ratio analysis added another layer of comparison. Follow-up extended to a median of 2.6 years, with an interquartile range of 0.8 to 5.6 years, long enough to capture recurrent rhythm burden rather than only immediate procedural outcomes.
One sentence captures the central message: IBD was associated with more adverse arrhythmia-related events after ablation.
Event Rates Favored the Non-IBD Comparator Group
The primary endpoint occurred in 81 patients with IBD, or 32.3%, compared with 640 matched comparators, or 26.3%. Incidence rates told the same story: 100.8 per 1000 person-years in the IBD group versus 73.3 per 1000 person-years in the comparator group. The adjusted hazard ratio for the composite endpoint was 1.30, with a 95% confidence interval of 1.03 to 1.64.
The excess risk did not appear evenly distributed across all components of the composite. Hospitalization for arrhythmia occurred more frequently in patients with IBD, with a hazard ratio of 1.29 and a 95% confidence interval of 1.02 to 1.64. Reablation and cardioversion did not differ between the two groups. In practical terms, the post-ablation gap was not primarily a signal of more repeat procedures or more rescue cardioversion; it was a signal of more acute arrhythmia-related admissions.
That pattern matters at the bedside because hospitalization often reflects a more destabilized clinical course, whether from symptomatic recurrence, more difficult rate or rhythm control, or lower tolerance for arrhythmic episodes. In patients already living with a chronic inflammatory disorder, a rhythm recurrence that might be managed in clinic for another patient may trigger inpatient observation or treatment more readily.
Why IBD May Continue to Influence Rhythm Outcomes
The cohort does not prove mechanism, but the biology is plausible. IBD is marked by systemic inflammation, immune activation, and periods of disease flare that can affect atrial and ventricular electrophysiology through cytokine signaling, autonomic imbalance, and indirect effects on volume status, anemia, nutrition, and medication exposure. Ablation can isolate or modify the arrhythmogenic substrate, yet it cannot fully remove the systemic drivers that may promote arrhythmia recurrence or complicate recovery after the procedure.
Inflammation also has a structural dimension. Chronic inflammatory activity can contribute to atrial remodeling, fibrosis, and altered conduction properties, all of which may make arrhythmias more likely to recur or make symptomatic episodes less well tolerated. If IBD activity remains uncontrolled, or if the patient cycles through flares and remission, the electrophysiologic substrate may remain unstable even after a technically successful ablation.
The clinical consequence is straightforward: rhythm management in IBD may need to be broader than the procedure itself. Coordination with gastroenterology, attention to inflammatory control, and careful review of drugs, electrolytes, and comorbid conditions may be as relevant to long-term rhythm stability as the ablation lesion set.
Win Ratio Analysis Confirmed the Direction of Effect
A hierarchical win ratio analysis reinforced the main result, with a win ratio of 0.80 and a 95% confidence interval of 0.65 to 0.99, P = 0.04. This method ranks outcomes in a prespecified order and can provide a more nuanced view of clinical tradeoffs than a single composite endpoint alone. Here, the win ratio indicated that patients with IBD were less likely to come out ahead across the sequence of rhythm-related outcomes.
The advantage of that approach is conceptual as well as statistical. When a composite endpoint is driven by events that differ in severity or clinical meaning, a hierarchical framework can show whether the overall signal is being pushed by the most consequential outcomes. In this study, the hierarchy aligned with the primary analysis and pointed again toward a modest but real excess of adverse rhythm-related burden in the IBD population.
What Clinicians Should Take From the Data
The study does not argue against catheter ablation in patients with IBD. It does suggest that the procedure should be viewed against a different baseline of risk. Patients with IBD may need closer follow-up after ablation, earlier reassessment when palpitations recur, and a lower threshold to investigate inflammatory activity or noncardiac contributors when arrhythmia symptoms persist.
The 30% higher hazard for the composite endpoint is not a dramatic failure signal, but it is clinically meaningful because it emerged in a matched national cohort and was consistent across incidence rates and hierarchical analysis. Hospitalization for arrhythmia emerged as the key differentiator, which may reflect both greater clinical instability and greater healthcare utilization after ablation in this population.
The study also leaves important questions unanswered. The dataset does not provide granular information on IBD subtype, disease activity, medication exposure, or procedural details that might explain which patients carry the highest risk. Whether active intestinal inflammation, biologic therapy, corticosteroid exposure, or prior thromboinflammatory burden modifies post-ablation outcomes remains unresolved. Those gaps limit patient-level risk prediction and leave room for future work to determine whether tighter inflammatory control improves rhythm durability after ablation.