Coronary sinus electrogram characteristics predict termination of AF with ablation and long-term clinical outcome

Abstract

Introduction: Markers predicting atrial fibrillation (AF) termination and freedom from AF/atrial tachycardia (AT) has been proposed. This study aimed to evaluate the role of novel coronary sinus (CS) electrogram characteristics in predicting the acute ablation response and freedom from AF/AT during follow-up.

Methods: Patients undergoing ablation for persistent AF as part of the Stochastic Trajectory Analysis of Ranked signals mapping study were included. Novel CS electrogram characteristics including CS cycle length variability (CLV) and CS activation pattern stability (APS) and proportion of low voltage zones (LVZs) were reviewed as potential predictors for AF termination on ablation and freedom from AF/AT during follow-up. The relationship between localized driver characteristics and CS electrogram characteristics was also assessed.

Results: Sixty-five patients were included. AF termination was achieved in 51 patients and 80% of patients were free from AF/AT during a follow-up of 29.5 ± 3.7 months. CS CLV of <30 ms, CS APS of ≥30% and proportion of LVZ < 30% showed high diagnostic accuracy in predicting AF termination on ablation and freedom from AF/AT during follow-up (CS CLV odds ratio [OR] 25.6, area under the curve [AUC] 0.91; CS APS OR 15.9, AUC 0.94; proportion of LVZs OR 21.4, AUC 0.88). These markers were independent predictors of AF termination on ablation and AF/AT recurrence during follow-up. Ablation of a smaller number of drivers that demonstrate greater dominance strongly correlate with greater CS organization.

Conclusion: Novel CS electrogram characteristics were independent predictors of AF termination and AF/AT recurrence during follow-up. These markers can potentially aid in predicting outcomes and guide ablation and follow-up strategies.

Keywords: atrial fibrillation; catheter ablation; coronary sinus; drivers; mapping.

Figure 1

(A–D) Demonstrates (A) STAR map in a posterior‐anterior view that shows an AFD on the high posterior wall. (B) Ablation here as shown on the CARTO map in a posterior‐anterior view resulted in AF termination to an AT as shown on the (C) BARD electrograms including PV signals, CS signals, ablation catheter signals (Map), and surface ECG. (D) BARD electrograms demonstrating a proportion of the unipolar CS signals obtained during the 5‐min recording post‐PVI. The electrograms demonstrate a stable CS activation pattern whereby CS 5 (highlighted by a star) is leading its neighboring electrodes as shown by the orange arrows. Throughout the 5‐min recording, this activation pattern was present 42% of the time, i.e., the activation pattern stability was 42%. As shown on the CS electrograms there was minimal CL variation within the CS with a CLV of 21 ms during the 5‐min recording. AF, atrial fibrillation; CLV, cycle length variability; CS, coronary sinus; ECG, electrocardiogram; PVI, pulmonary vein isolation

Figure 2

(A–D) Demonstrates (A) STAR map in an anterior‐posterior view that shows an AFD on the mid anterior wall. (B) Ablation here as shown on the CARTO map in an anterior‐posterior view resulted in AF termination to an AT as shown on the (C) BARD electrograms including PV signals, CS signals, ablation catheter signals (Map), and surface ECG. (D) BARD electrograms demonstrating a proportion of the unipolar CS signals obtained during the 5‐minute recording post‐PVI. The electrograms demonstrate a stable CS activation pattern whereby CS 10 (highlighted by a star) is leading its neighboring electrodes as shown by the orange arrows. Throughout the 5‐min recording, this activation pattern was present for 45% of the time, i.e., the activation pattern stability was 45%. As shown on the electrograms there was minimal CL variation within the CS with a CLV of 19.9 ms during the 5‐min recording. CLV, cycle length variability; CS, coronary sinus; ECG, electrocardiogram; PVI, pulmonary vein isolation

Figure 3

(A–C) Demonstrates Kaplan–Meier curves that show a significant difference in survival free from AF/AT in patients based on differences in (A) CS activation pattern stability whereby patients with a CS activation pattern stability of ≥30% have an increase survival free from AF/AT compared with patients with a CS activation pattern stability of <30%. (B) CS CLV whereby patients with a CS CLV of <30 ms have an increase survival free from AF/AT compared with patients with a CS CLV of ≥30 ms. (C) Proportion of LVZs whereby patients with a proportion of LVZs of <30% have an increased survival free from AF/AT compared to patients with a proportion of LVZs of ≥30%. AF, atrial fibrillation; AT, atrial tachycardia; CLV, cycle length variability; CS, coronary sinus; LVZs, low voltage zones