Association of isoproterenol infusion during catheter ablation of atrial fibrillation with outcomes: insights from the UC San Diego AF Ablation Registry

BackgroundHigh-dose isoproterenol infusion is a useful provocative maneuver to elicit triggers of atrial fibrillation (AF) during ablation. We evaluated whether the use of isoproterenol infusion to elicit triggers of AF after ablation is associated with differential outcomes.MethodsWe performed a retrospective study of all patients who underwent de novo radiofrequency catheter ablation of AF enrolled in the University of California, San Diego AF Ablation Registry. The primary outcome was freedom from atrial arrhythmias on or off antiarrhythmic drugs (AAD).ResultsOf 314 patients undergoing AF ablation, 235 (74.8%) received isoproterenol while 79 (25.2%) did not. Among those who received isoproterenol, 11 (4.7%) had additional triggers identified. There were no statistically significant differences in procedure time (p = 0.432), antiarrhythmic drug use (p = 0.289), procedural complications (p = 0.279), recurrences of atrial arrhythmias on or off AAD [adjusted hazard ratio (AHR) 0.92 (95% CI 0.58-1.46); p = 0.714], all-cause hospitalizations [AHR 1.00 (95% CI 0.60-1.67); p = 0.986], or all-cause mortality [AHR 0.14 (95% CI 0.01-3.52); p = 0.229] between groups.ConclusionsIn this registry analysis, use of isoproterenol is safe but was not associated with a reduction in recurrence of atrial arrhythmias

Association between specific antiarrhythmic drug prescription in the post-procedural blanking period and recurrent atrial arrhythmias after catheter ablation for atrial fibrillation.

PurposeTo evaluate if specific AADs prescribed in the blanking period (BP) after catheter ablation of atrial fibrillation (AF) may be associated with reduced risk of early recurrence (ER) and/or late recurrence (LR) of atrial arrhythmias.MethodsA total of 478 patients undergoing first-time ablation at a single institution were included. Outcomes were: ER, LR, discontinuation of AAD less than 90 days post-ablation, and second ablation. ER was defined as AF, atrial flutter (AFL), or atrial tachycardia (AT) > 30 seconds within BP. LR was defined as AF/AFL/AT > 30 seconds after BP.ResultsOf 478 patients, 14.9% were prescribed no AAD, 26.4% propafenone/flecainide, 34.5% sotalol/dofetilide, 10.7% dronedarone, and 13.6% amiodarone. Patients prescribed amiodarone were more likely to have persistent AF, hypertension, diabetes, and other comorbidities. In unadjusted analyses, there were no differences between groups in relation to ER (log rank P = 0.171), discontinuation of AAD before ninety days post-ablation (log rank P = 0.235), or freedom from second ablation (log rank P = 0.147). After multivariable adjustment, patients prescribed amiodarone or dronedarone were more likely to experience LR than those prescribed no AAD [Adjusted Hazard Ratio (AHR) 1.83, 95% CI 1.10-3.04, p = 0.02; AHR 1.79, 95% CI 1.05-3.05, p = 0.03, respectively].ConclusionFollowing first-time catheter ablation, there were no differences between specific AAD prescription and risk of ER, while those prescribed amiodarone or dronedarone in the BP were more likely to experience LR than those prescribed no AAD, which may represent an association due to confounding by indication

Comparison of Outcomes After Ablation of Atrial Fibrillation in Patients With Heart Failure With Preserved Versus Reduced Ejection Fraction.

Catheter ablation improves outcomes in atrial fibrillation (AF) patients with heart failure (HF) with reduced ejection fraction (HFrEF). We sought to evaluate the efficacy and safety of catheter ablation of AF in HF patients with a preserved ejection fraction (HFpEF). We performed a retrospective study of all patients who underwent de novo radiofrequency catheter ablation enrolled in the UC San Diego AF Ablation Registry. The primary outcome was recurrence of all atrial arrhythmias on or off antiarrhythmic drugs (AAD). Of 547 total patients, 51 (9.3%) had HFpEF, 40 (7.3%) had HFrEF, and 456 (83.4%) were without HF. There was no difference in recurrence of atrial arrhythmias on or off AAD (Adjusted Hazard Ratio [AHR] 1.92 [95% CI 0.97 to 3.83] for HFpEF vs HFrEF and AHR 0.90 [95% CI 0.59 to 1.39] for HFpEF vs no HF) or off AAD (AHR 1.96 [95% CI 0.99 to 3.90] for HFpEF vs HFrEF and AHR 1.14 [95% CI 0.74 to 1.77] for HFpEF vs no HF). There was also no difference in rates of all-cause hospitalizations (AHR 1.80 [95% CI 0.97 to 3.33] for HFpEF vs HFrEF and AHR 2.05 [95% CI 1.30 to 3.23] for HFpEF vs no HF) or rates of all-cause mortality (AHR 0.53 [95% CI 0.05 to 6.11] for HFpEF vs HFrEF and AHR 2.46 [95% CI 0.34 to 17.92] for HFpEF vs no HF). There were no significant differences in AAD use (p = 0.176) or procedural complications between groups (p = 0.980). In conclusion, there were no significant differences in arrhythmia-free survival between patients with HFpEF and HFrEF that underwent catheter ablation of AF

Association between early recurrences of atrial tachyarrhythmias and long-term outcomes in patients after repeat atrial fibrillation ablation.

PurposeEarly recurrence of atrial tachyarrhythmia (ER) is predictive of late recurrence of atrial tachyarrhythmia (LR) after first-time atrial fibrillation (AF) ablation, but the association in patients undergoing repeat AF ablation is unknown. We aim to determine the incidence and prognostic significance of ER after repeat ablation.MethodsA total of 259 consecutive patients (mean age 64 years, 75.3% male) undergoing repeat AF ablation with complete follow-up data were included at a single institution from 2010 to 2015. ER and LR were defined as atrial tachyarrhythmia (AF, atrial flutter or atrial tachycardia) > 30 s within the 3-month blanking period (BP) and after the 3-month BP, respectively.ResultsER occurred in 79/259 (30.5%), and LR occurred in 138/259 (53%) at a median follow-up of 1221 (IQR: 523-1712) days. Four-year freedom from LR was 22% and 56% in patients with and without ER, respectively (p < 0.001). After multivariate adjustment, ER was strongly associated with LR, cardioversion post BP, and repeat ablation, but not associated with hospitalization. Compared to those with no ER, there was a higher risk of LR when ER occurred within the first month of the BP [month 1: hazard ratio (HR) 2.32, confidence interval (CI) 1.57-3.74, p < 0.001; month 2: HR 2.01, CI 1.13-3.83, p = 0.02; month 3: HR 1.46, CI 0.5-3.36, p = 0.37], however the prediction of LR based on timing within the BP was poor (area under curve 0.64).ConclusionFollowing repeat AF ablation, ER is strongly associated with LR, cardioversion post BP, and repeat ablation

Meta-analysis of the Usefulness of Catheter Ablation of Atrial Fibrillation in Patients With Heart Failure With Preserved Ejection Fraction.

Catheter ablation improves clinical outcomes in atrial fibrillation (AF) patients with heart failure (HF) with reduced ejection fraction (HFrEF). However, the role of catheter ablation in HF with a preserved ejection fraction (HFpEF) is less clear. We performed a literature search and systematic review of studies that compared AF recurrence at one year after catheter ablation of AF in patients with HFpEF versus those with HFrEF. Risk ratio (RR; where a RR <1.0 favors the HFpEF group) and mean difference (MD; where MD <0 favors the HFpEF group) 95% confidence intervals (CI) were measured for dichotomous and continuous variables, respectively. Six studies with a total of 1,505 patients were included, of which 764 (51%) had HFpEF and 741 (49%) had HFrEF. Patients with HFpEF experienced similar recurrence of AF 1 year after ablation on or off antiarrhythmic drugs compared with those with HFrEF (RR 1.01; 95% CI 0.76, 1.35). Fluoroscopy time was significantly shorter in the HFpEF group (MD -5.42; 95% CI -8.51, -2.34), but there was no significant difference in procedure time (MD 1.74; 95% CI -11.89, 15.37) or periprocedural adverse events between groups (RR 0.84; 95% CI 0.54,1.32). There was no significant difference in hospitalizations between groups (MD 1.18; 95% CI 0.90, 1.55), but HFpEF patients experienced significantly less mortality (MD 0.41; 95% CI 0.18, 0.94). In conclusion, based on the results of this meta-analysis, catheter ablation of AF in patients with HFpEF appears as safe and efficacious in maintaining sinus rhythm as in those with HFrEF