Pulmonary vein isolation combined with substrate modification for persistent atrial fibrillation treatment in patients with valvular heart diseases

Catheter Ablation for Atrial Fibrillation in Structural Heart Disease: A Review

Atrial fibrillation (AF) is the most common arrhythmia encountered in clinical practice. Patients with structural heart disease (SHD) are at an increased risk of developing this arrhythmia and are particularly susceptible to the deleterious hemodynamic effects it carries. In the last two decades, catheter ablation (CA) has emerged as a valuable strategy for rhythm control and is currently part of the standard care for symptomatic relief in patients with AF. Growing evidence suggests that CA of AF may have potential benefits that extend beyond symptoms. In this review, we summarize the current knowledge of this intervention on SHD patients.

Dispersion-guided ablation in conjunction with circumferential pulmonary vein isolation is superior to stepwise ablation approach for persistent atrial fibrillation

BACKGROUND

Due to the lack of optimal ablation strategy, the success rate of persistent atrial fibrillation (AF) is still low. We hypothesize that a strategy that targeting pulmonary triggers and dispersion areas in atria improves prognosis of persistent AF.

METHODS

We prospectively enrolled 142 persistent AF patients admitted for catheter ablation. These patients were randomly assigned in a 1:1 ratio to ablation with circumferential pulmonary vein isolation (CPVI) + ablation of electrogram dispersion areas (71 patients, group A) or stepwise ablation strategy (71 patients, group B).

RESULTS

Procedural time and fluoroscopy time did not differ between group A and group B (204.6 ± 26.9 min vs 207.8 ± 26.3 min and 7.3 ± 1.3 min vs 7.1 ± 1.3 min, respectively, P > 0.05), however, radiofrequency delivery time in group A was significantly shorter than that in group B (70 ± 7.2 min vs 83.2 ± 9.1 min, P < 0.001). In total, 265 electrogram dispersion areas were identified in 67 patients, and the most prominent areas were roof, bottom, and inferoposterior wall. The rates of acute AF endpoint (including AF termination and AFCL elongation >30 ms) and termination in group A were significantly higher than that in group B (97.2% vs. 71.8% and 70.4% vs. 15.5%, respectively, P < 0.001). During a follow-up period of 204 ± 67 days, both AF-free and AF/AT-free survival in group A were significantly higher than that in group B (P = 0.012 and P = 0.014, respectively).

CONCLUSION

Dispersion-guided ablation in conjunction with CPVI is efficient, personalized, and accurate for persistent AF.

Efficacy and safety of catheter ablation for long-standing persistent atrial fibrillation in women

OBJECTIVES

It is uncertain whether gender affects the outcomes of catheter ablation (CA) for atrial fibrillation (AF). The objective of the study is to evaluate the efficacy and safety of CA for long-standing persistent AF in women.

METHODS

Between January 2010 and May 2011, 220 consecutive patients (73 females, 33.2%), with long-standing persistent AF who underwent CA were prospectively recruited. Gender-related differences in clinical presentation, periprocedural complications, and outcomes were compared.

RESULTS

Women were less likely to have lone AF than men (27.4% vs 47.6%; P = 0.004). The incidence of rheumatic heart disease was higher in women (19.2% in women vs 1.4% in men; P < 0.001). Women had a lower initial ablation success rate than men (35.6% vs 57.1%; P = 0.003). Hematomas occurred more often in women (6.8% in women vs 0.7% in men; P = 0.027). A Cox regression analysis demonstrated total duration of AF (per month, hazard ratio [HR] 1.003, confidence interval [CI] 1.001-1.006; P = 0.006) and gender (HR 1.663, CI 1.114-2.485; P = 0.013) as the independent predictors for recurrence after the first CA.

CONCLUSIONS

Women and long AF duration were closely related to the recurrence of AF after the first ablation in patients with long-standing persistent AF. Women also had a higher risk of vascular complications.

Impact of chronic obstructive pulmonary disease on procedural outcomes and quality of life in patients with atrial fibrillation undergoing catheter ablation

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a risk factor for atrial fibrillation (AF). The aim of this study was to investigate the impact of COPD on outcomes of catheter ablation in patients with AF in terms of recurrence and quality of life (QoL).

METHODS

In this prospective study, 550 consecutive patients with symptomatic, medication-refractory AF underwent first catheter ablation. Patients were classified into those with COPD (group 1, n = 54) and those without COPD (group 2, n = 496). Patients were followed up for atrial tachyarrhythmia (ATa) recurrence for at least 24 months. The Medical Outcomes Study SF-36 Health Survey was used to assess QoL at baseline and 24 months after ablation.

RESULTS

After a single ablation, 24 patients in group 1 (44.4%) and 142 in group 2 (28.6%) had ATa recurrence during a mean follow-up of 31.4 ± 4.8 months (P = 0.016). The second ablation was performed in 19 patients (35.2%) from group 1 and in 109 patients (22.0%) from group 2 (P = 0.029). Multivariate logistic analysis showed that nonparoxysmal AF (P = 0.013, OR = 1.767, 95% CI: 1.129-2.765) as well as the presence of COPD (P = 0.029, OR = 1.951, 95% CI: 1.070-3.557) was the independent predictor for higher ATa recurrence. Moreover, patients in group 1 had significantly lower baseline scores on all SF-36 Health Survey subscales. At 24-month follow-up, both mental component summary and physical component summary scores improved markedly in group 1 and 2.

CONCLUSIONS

Although the presence of COPD predicted higher recurrence after single-catheter ablation in AF patients, significant improvements in QoL were observed in the postablation COPD population.

Ablation of atrial tachycardia occurring after catheter ablation of atrial fibrillation in patients with corrected rheumatic valve disease

OBJECTIVE

The purpose of this study is to investigate the mechanism and the effectiveness of ablation of atrial tachycardia (AT) recurring after atrial fibrillation (AF) ablation in patients with rheumatic valvular disease (RVD) and mitral valve prosthesis.

METHODS

Twenty-eight consecutive patients with RVD and mitral valve prosthesis and a 1:2 matched control group (n = 56) without RVD underwent reablation for recurrent AT after catheter ablation of long-standing persistent AF.

RESULTS

Macro- or localized reentrant ATs were identified in 47 (87 %) of 54 ATs from RVD group and in 65 (78.3 %) of 83 ATs from control. There were more average ATs per patient in the RVD group than in the control (1.9 ± 0.6 vs.1.5 ± 0.6, P = 0.002). The proportion of patients having ≥2 ATs was significantly higher in the RVD group than in the control (78.6 vs.41.1 %, P = 0.001). In the RVD group, ATs were successfully ablated in 44 (81.5 %) of 54 ATs and terminated in 18 (64.3 %) of 28 patients. In the control, ATs were successfully ablated in 72 (86.7 %) of 83 ATs and terminated in 45 (80.4 %) of 56 patients, P = 0.54 and 0.10, respectively. After a mean follow-up of 13 months, 16 patients (57.1 %) from the RVD group and 45 patients (80.4 %) from the control were free of further recurrence, P = 0.02.

CONCLUSIONS

Macro- or localized reentries were the predominant type of recurrent AT after long-standing persistent AF ablation in both the RVD and the control groups. Compared with patients without RVD, patients with RVD had more average number of ATs and had higher probability of further recurrence despite the similar acute effectiveness of reablation.

Radiofrequency ablation of atrial fibrillation in patients with mechanical mitral valve prostheses safety, feasibility, electrophysiologic findings, and outcomes

OBJECTIVES

The purpose of this study was to evaluate the feasibility, safety, and outcomes of radiofrequency ablation of atrial fibrillation (AF) in patients with mechanical mitral valve replacement (MVR).

BACKGROUND

The role of ablative therapy in patients with MVR is not yet established, with safety concerns and very few outcome data.

METHODS

Between January 2003 and December 2008, we followed up 81 patients with MVR undergoing first-time AF ablation (compared with 162 age- and sex-matched controls). Arrhythmia recurrences were identified by symptoms with documentation, event monitoring, Holter monitoring, and electrocardiograms.

RESULTS

All MVR and control patients underwent ablation under therapeutic international normalized ratio. No entrapment of catheters or stroke occurred. There were no differences in terms of procedure-related complications between the groups (p = NS). Patients with MVR had larger atria (p < 0.0001), lower left ventricular ejection fractions (p = 0.0001), and more concomitant atrial flutter at baseline (p < 0.0001). Over a 24-month follow-up, they had higher recurrence rates compared with controls (49.4% vs. 27.7% after a single ablation, p = 0.0006). The creation of flutter lines significantly reduced recurrences in patients with any history of atrial flutter (16.7% vs. 60.9%, p = 0.009). At last follow-up, 82.7% of MVR patients had their arrhythmia controlled (69.1% not receiving antiarrhythmic drugs).

CONCLUSIONS

Radiofrequency ablation is feasible and safe for patients with MVR. It allowed restoration of sinus rhythm in a substantial proportion of patients undergoing ablation. An abnormal atrial substrate underlies recurrences in these patients. The ablation procedure needs to be further refined with a focus on extra pulmonary vein triggers and concomitant flutters to improve outcomes.

Pulmonary vein isolation with complex fractionated atrial electrogram ablation for paroxysmal and nonparoxysmal atrial fibrillation: A meta-analysis

BACKGROUND

Pulmonary vein isolation (PVI) is recognized as a potentially curative treatment for atrial fibrillation (AF). Ablation of complex fractionated atrial electrograms (CFAEs) in addition to PVI has been advocated as a means to improve procedural outcomes, but the benefit remains unclear.

OBJECTIVE

This study sought t synthesize the available data testing the incremental benefit of adding CFAE ablation to PVI.

METHODS

We performed a meta-analysis of controlled studies comparing the effect of PVI with CFAE ablation vs. PVI alone in patients with paroxysmal and nonparoxysmal AF.

RESULTS

Of the 481 reports identified, 8 studies met our inclusion criteria. There was a statistically significant increase in freedom from atrial tachyarrhythmia (AT) with the addition of CFAE ablation (relative risk [RR] 1.15, P = .03). In the 5 reports of nonparoxysmal AF (3 randomized controlled trials, 1 controlled clinical trial, and 1 trial using matched historical controls), addition of CFAE ablation resulted in a statistically significant increase in freedom from AT (n = 112 of 181 [62%] for PVI+CFAE vs. n = 84 of 179 [47%] for PVI alone; RR 1.32, P = .02). In trials of paroxysmal AF (3 randomized controlled trials and 1 trial using matched historical controls), addition of CFAE ablation did not result in a statistically significant increase in freedom from AT (n = 131 of 166 [79%] for PVI+CFAE vs. n = 122 of 164 [74%] for PVI alone; RR 1.04, P = .52).

CONCLUSION

In these studies of patients with nonparoxysmal AF, addition of CFAE ablation to PVI results in greater improvement in freedom from AF. No additional benefit of this combined approach was observed in patients with paroxysmal AF.