The relationship between systemic immune-inflammation index and recurrence after cryoballoon ablation for paroxysmal atrial fibrillation.

Background: The effectiveness of lesion formation during cryoballoon ablation (CBA) may be influenced by the extent of acute local inflammation induced during the ablation process. This study aims to evaluate the predictive value of inflammatory markers following CBA.

Methods: A total of 102 consecutive patients with paroxysmal atrial fibrillation (AF) who underwent CBA (51.9% male; mean age 56.7 ± 11.5 years) were prospectively included in the study. Blood samples for Systemic Immune-Inflammation Index (SII), C-reactive protein (CRP), lymphocyte counts (LC) were collected from all participants prior to, and within 24 h post-procedure. SII was calculated as platelet count × neutrophil count / lymphocyte count. 12-lead electrocardiograms, clinical evaluations, medical history reviews, and 24-hour Holter monitoring were performed at one, three-, and six-months post-ablation. Recurrences of AF occurring beyond the initial 30-day blanking period were documented and analyzed.

Results: Over a mean follow-up period of 12.3 ± 5.1 months, AF recurrence was observed in 30 (29.4%) patients. SII, CRP, LC, and left atrial end-systolic diameter (LAD), were associated with AF recurrence. Multivariable Cox regression analysis identified post-ablation SII levels as the sole independent predictor of AF recurrence (hazard ratio [HR]: 0.139; 95% confidence interval [CI]: 0.052-0.369; p < 0.001). Receiver operating characteristic (ROC) curve analysis determined an SII cut-off value of 900 for predicting AF recurrence, yielding a sensitivity of 80.0% and specificity of 63.9%. The area under the curve (AUC) was 0.72 (p < 0.001).

Conclusion: Lower post-ablation levels of SII predict AF recurrence following CBA.