Long-term outcome of atrial fibrillation ablation: impact and predictors of very late recurrence.

INTRODUCTION: Ablation eliminates atrial fibrillation (AF) in studies with 1 year follow-up, but very late recurrences may compromise long-term efficacy. In a large cohort, we sought to describe the determinants of delayed recurrence after AF ablation. METHODS AND RESULTS: Seven hundred and seventy-four patients with AF (428 paroxysmal [PAF, 55%] and 346 persistent or longstanding persistent [PersAF, 45%]) underwent wide area circumferential ablation (WACA, 62%) or pulmonary vein isolation (38%). Over 3.0 ± 1.9 years, there were 135 recurrences in PAF patients and 142 in PersAF patients. AF elimination was achieved in 61% of patients with PersAF at 2 years after last ablation and in 71% of patients with PAF (P = 0.04). This finding was related to a higher initial rate of very late recurrence in PersAF. From 1.0 to 2.5 years, the recurrence increased by 20% (from 37% to 57%) in PersAF patients versus only 12% (from 27% to 39%) in PAF patients. Independent predictors of overall recurrence included diabetes (HR 1.9 [1.3-2.9], P = 0.002) and PersAF (HR 1.6 [1.2-2.0], P < 0.001). Independent predictors of very late recurrence included PersAF (HR 1.7 [1.1-2.7], P = 0.018) and WACA (HR 1.8 [1.1-2.7], P = 0.018), while diabetes came close to significance. In PAF patients, left atrial size >45 mm was identified as an AF-type specific predictor (HR 2.4 [1.3-4.7], P = 0.009), whereas in PersAF patients, no unique predictors were identified. CONCLUSION: Late recurrences reduced the long-term efficacy of AF ablation, particularly in patients with PersAF and underlying cardiovascular diseases.

Substrate and procedural predictors of outcomes after catheter ablation for atrial fibrillation in patients with hypertrophic cardiomyopathy.

BACKGROUND: Hypertrophic cardiomyopathy (HCM) is often accompanied by atrial fibrillation (AF) due to diastolic dysfunction, elevated left atrial pressure, and enlargement. Although catheter ablation for drug-refractory AF is an effective treatment, the efficacy in HCM remains to be established. METHODS: Thirty-three consecutive patients (25 male, age 51 +/- 11 years) with HCM underwent pulmonary vein (PV) isolation (n = 8) or wide area circumferential ablation with additional linear ablation (n = 25) for drug-refractory AF. Twelve-lead and 24-hour ambulating ECGs, echocardiograms, event monitor strips, and SF 36 quality of life (QOL) surveys were obtained before ablation and for routine follow-up. RESULTS: Twenty-one (64%) patients had paroxysmal AF and 12 (36%) had persistent/permanent AF for 6.2 +/- 5.2 years. The average ejection fraction was 0.63 +/- 0.12. The average left atrial volume index was 70 +/- 24 mL/m(2). Over a follow-up of 1.5 +/- 1.2 years, 1-year survival with AF elimination was 62%(Confidence Interval [CI]: 66-84) and with AF control was 75%(CI: 66-84). AF control was less likely in patients with a persistent/chronic AF, larger left atrial volumes, and more advanced diastolic disease. Additional linear ablation may improve outcomes in patient with severe left atrial enlargement and more advanced diastolic dysfunction. Two patients had a periprocedureal TIA, one PV stenosis, and one died after mitral valve replacement from prosthetic valve thrombosis. QOL scores improved from baseline at 3 and 12 months. CONCLUSION: Outcomes after AF ablation in patients with HCM are favorable. Diastolic dysfunction, left atrial enlargement, and AF subtype influence outcomes. Future studies of rhythm management approaches in HCM patients are required to clarify the optimal clinical approach.

Effect of radiofrequency ablation of atrial flutter on the natural history of subsequent atrial arrhythmias.

UNLABELLED: Flutter Ablation and Subsequent Arrhythmia. INTRODUCTION: Patients with atrial flutter (AFL) treated medically are at high risk for subsequent development of atrial fibrillation (AF). Whether curative radiofrequency ablation of AFL can modify the natural history of arrhythmia progression is not clear. We aimed to determine whether ablation of AFL decreases the subsequent development of AF in patients without previous AF. METHODS AND RESULTS: Patients with AFL as the sole atrial arrhythmia were selected from patients who underwent successful AFL ablation at Mayo Clinic between 1997 and 2003 (N = 137). The cohort was divided by presence (n = 50) or absence (n = 87) of structural heart disease. A control group comprised 59 patients with AFL and no history of paroxysmal AF, who received only medical therapy. Occurrence of AF after AFL ablation was compared among study groups and controls. Symptomatic AF occurred in 49 patients during 5 years of follow-up after AFL ablation, with similar frequency in both study groups. The cumulative probability of paroxysmal and chronic AF was similar in controls and each study group. By multivariate analysis, the AFL ablation procedure carries significant risk of AF occurrence during follow-up. Fifty patients discontinued antiarrhythmic drugs after AFL ablation, and the rate of cardioversions decreased. CONCLUSION: Successful ablation of AFL does not improve the natural history of atrial arrhythmia progression; postablation AF is frequent. This suggests that AFL may be initiated by bursts of AF and that in the absence of AFL substrate the AF continues to progress.

Success of ablation for atrial fibrillation in isolated left ventricular diastolic dysfunction: a comparison to systolic dysfunction and normal ventricular function.

BACKGROUND: The efficacy of radiofrequency ablation for atrial fibrillation (AF) in patients with left ventricular (LV) systolic dysfunction and isolated diastolic dysfunction is uncertain. METHODS AND RESULTS: A prospective cohort of patients with normal and abnormal LV function underwent ablation for antiarrhythmic drug (AAD)-refractory AF. Three groups were compared: 111 patients with systolic dysfunction, defined as LV ejection fraction (LVEF) ≤40%; 157 patients with isolated diastolic dysfunction but preserved LVEF ≥50%; and 100 patients with normal LV function. The primary end point was AAD-free AF elimination at 1 year after ablation. This end point was achieved in 62% of patients with systolic dysfunction, 75% of those with diastolic dysfunction, and 84% of controls (P=0.007). AF control on or off AADs was achieved in 76% of patients with systolic dysfunction, 85% of those with diastolic dysfunction, and 89% of controls (P=0.08). In the systolic dysfunction group, 49% experienced an increase in LVEF by ≥5% after ablation, of which 64% achieved normal LVEF. In the diastolic dysfunction group, 30% of patients demonstrated at least 1 grade improvement in diastolic dysfunction. Multivariable analysis demonstrated an increased relative risk of arrhythmia recurrence of 1.8 (95% CI, 1.1 to 3.1; P=0.02) in systolic dysfunction and 1.7 (1.0 to 2.7; P=0.04) in isolated diastolic dysfunction compared with normal function. CONCLUSIONS: Although an ablative approach for AF in patients with systolic or diastolic dysfunction is associated with an increased long-term recurrence risk, there is potential for substantial quality-of-life improvement and LV functional benefit.

Long-term quality of life after ablation of atrial fibrillation the impact of recurrence, symptom relief, and placebo effect.

OBJECTIVES: We sought to determine the relationship between atrial fibrillation (AF) ablation efficacy, quality of life (QoL), and AF-specific symptoms at 2 years. BACKGROUND: Although the primary goal of AF ablation is QoL improvement, this effect has yet to be demonstrated in the long term. METHODS: A total of 502 symptomatic AF ablation recipients were prospectively followed for recurrence, QoL, and AF symptoms. RESULTS: In 323 patients with 2 years of follow-up, 72% achieved AF elimination off antiarrhythmic drugs (AADs), 15% achieved AF control with AADs, and 13% had recurrent AF. The physical component summary scores of the Medical Outcomes Study Short Form 36 increased from 58.8 +/- 20.1 to 76.2 +/- 19.2 (p < 0.001) and the mental component summary scores of the Short Form 36 increased from 65.3 +/- 18.6 to 79.8 +/- 15.8 (p < 0.001). Post-ablation QoL improvements were noted across ablation outcomes, including recurrent AF (change in physical component summary: 12.1 +/- 19.7 and change in mental component summary: 9.7 +/- 17.9), with no significant differences in QoL improvement across 3 ablative efficacy outcomes. However, in 103 patients who completed additional assessment with Mayo AF Symptom Inventories (on a scale of 0 to 48), those with AF elimination off AADs had a change in AF symptom frequency score of -9.5 +/- 6.3, which was significantly higher than those with AF controlled with AADs (-5.6 +/- 3.8, p = 0.03) or those with recurrent AF (-3.4 +/- 8.4, p = 0.02). Independent predictors of limited QoL improvement included higher baseline QoL, obesity, and warfarin use at follow-up. CONCLUSIONS: AF ablation produces sustained QoL improvement at 2 years in patients with and without recurrence. AF-specific symptom assessment more accurately reflects ablative efficacy.