Introduction: Increasingly, catheter ablation for atrial fibrillation (AF) has been utilized for rhythm control and to improve quality of life (QoL). Data are limited on patient-centered ablation outcomes in individuals with chronic kidney disease (CKD). Objective: To examine clinical outcomes and QoL following AF ablation in CKD patients from a large patient-reported outcomes (PRO) database. Methods: All patients undergoing AF ablation (2013-2016) at our center were enrolled and assessed for outcomes using automated PRO surveys (baseline, 3 and 6 months after ablation, every 6 months thereafter). This analysis captured data at 1- and 3-year follow-up. CKD was defined as estimated glomerular filtration rate (eGFR) <60 ml/min using the 2021 CKD-EPI equation. The atrial fibrillation symptom severity scale (AFSSS) was used as the main measure for QoL assessment. In addition, data were collected on clinical improvement by patient report, AF burden, and healthcare utilization. Results: A total of 488 patients were identified (66% male, mean age 68.5, 56.2% persistent AF). QoL was significantly improved from baseline median (IQR) AFSSS of 14 (6-19.5) to 3 (0-9) at 1-year and 4 (0-9.5) at 3-year; P≤0.0001 for both. About 90% of patients reported improvement in their overall AF-related symptoms both at 1- and 3-year follow up. The proportion of patients in AF at the time of completion of the baseline survey was 51.2%, and this decreased to 6.2% at 1-year and 9.7% at 3-year follow up (P<0.0001 for both). AF burden was significantly reduced at 1-year and 3-year including frequency and duration of episodes (P<0.05 for both), with associated decrease in ER visits and hospitalizations; P<0.0001 for all comparisons. The proportion of patients on antiarrhythmics decreased from 61.8% at baseline to 35.6% and 22.7% at 1-year and 3-year, respectively (P<0.0001 for both). Conclusions: In a large AF-specific PRO system, catheter ablation for AF was associated with a significant improvement of QoL in most patients with CKD; with a decrease in AF burden and healthcare utilization.
Cyclic Variation of Spectral Parameters for the Differentiation of Atrial Myocardium Before and Immediately Following Radiofrequency Ablation
Radiofrequency ablation (RFA) is a common treatment of atrial fibrillation. However, current treatment is associated with a greater than 20% recurrence rate, in part due to inadequate monitoring of tissue viability during ablation. Spectral parameters, in particular cyclic variation of integrated backscatter (CVIB), have shown promise as early indicators of myocardial recovery from ischemia. Our aim was to demonstrate the use of spectral parameters to differentiate atrial myocardium before and after radiofrequency ablation. An AcuNav 10 F catheter was used to collect radiofrequency signals from the posterior wall of the left atrium of patients before and immediately after RFA for AF. The normalized power spectrum was obtained and three spectral parameters (integrated backscatter [IB], slope, and intercept) were extracted across two continuous heart cycles. Parameters were gated for ventricular end-diastole and compared before and after ablation. Additionally, the cyclic variation of each of these three parameters was generated as an average of the variation across the two recorded heart cycles. Data from 14 patients before and after ablation demonstrated a significant difference in the magnitude of the cyclic variation of integrated backscatter (9.0 vs. 6.0 dB, p < .001) and cyclic variation of the intercept (14.0 vs. 11.5 dB, p = .04). No significant difference was noted in the magnitude of the cyclic variation of the slope. Among spectral parameters gated for end-diastole, significant differences were noted in the slope (−4.39 vs. −3.73 dB/MHz, p = .002) and intercept (16.8 vs. 11.9 dB, p = .002). No significant difference was noted in the integrated backscatter. Spectral parameters are able to differentiate atrial myocardium before and immediately following ablation and may be useful in monitoring atrial ablations.
Super and Nonresponders to Catheter Ablation for Atrial Fibrillation: A Quality-of-Life Assessment Using Patient Reported Outcomes
Background: Atrial fibrillation (AF) ablation targets improvement in quality of life (QoL). Data is scarce on predictors of QoL improvement following ablation. We aimed to investigate the clinical characteristics underlying differential response in QoL after AF ablation (with or without arrhythmia recurrence). Methods: All patients undergoing AF ablation (2013–2016) at our center were prospectively enrolled in a fully automated patient-reported outcomes registry. A large number of variables were collected including AF symptom severity scale and AF burden (as indicated by AF frequency and duration scores). Patients were divided into 3 groups based on self-report of QoL improvement: remarkable (super responders), mild/moderate, and unchanged or worse (nonresponders). Univariable and multivariable logistic regression models assessed clinical characteristics and QoL outcomes. Results: A total of 956 patients were included (25% females, mean age 63.9). Most patients (≈80%) were super responders (n=761), 138 (14.4%) had mild/moderate improvement, and 57 (5.9%) were nonresponders. The strongest predictors of remarkable QoL improvement were freedom of arrhythmia recurrence (OR, 2.42 [95% CI, 1.27–4.59], P =0.007) and lower AF burden at 12 months. Similarly, higher AF burden was significantly associated with clinical nonresponse. In patients with observed clinical recurrence-QoL mismatch, changes in AF burden at 12 months were the main predictors of QoL outcome, with lower burden predicting higher improvement in QoL and vice versa. Conclusions: Most patients derive significant QoL benefit from AF ablation. Freedom from arrhythmia recurrence and lower AF burden predict remarkable QoL improvement following ablation.