Ablation for Persistent AF Without Circumferential PVI

In This Article

Abstract and Introduction
Methods
Results
Discussion
Limitations
Conclusion
References

Abstract and Introduction

Abstract

Long-Term Follow-Up of Linear Ablation for AF. Background: The long-term outcome of radiofrequency catheter ablation in persistent atrial fibrillation (AF) patients remains controversial due to different procedural strategies. This study aimed to present the clinical outcome of a pure linear ablation approach without circumferential pulmonary vein isolation (CPVI) over an extended (>5 years) follow-up period.

Methods: From January 2005 to December 2009, 120 consecutive patients (94 men; age, 53.6 ± 10.3 years) with drug-refractory persistent AF that underwent pure linear ablation using AF termination as the desired procedural endpoint were enrolled.

Results: In the primary procedure, sinus rhythm was restored by ablation in 75 (62.5%) patients, and the remaining 45 patients in whom AF could not be terminated by ablation received electrical cardioversion. During a median follow-up period of 5.1 (range 3.2–7.5) years, sinus rhythm was maintained in 48 (40.0%) patients without any antiarrhythmic drugs after a single procedure. There was a higher long-term success in the patients in whom AF was terminated by ablation than in those requiring cardioversion (49.3 vs. 24.4%; P = 0.007).

Conclusion: Linear catheter ablation without CPVI is effective for persistent AF. Patients with AF terminated by ablation were associated with a better long-term outcome than those requiring cardioversion

Introduction

Circumferential pulmonary vein isolation (CPVI) is a basic technique but insufficient for curing persistent atrial fibrillation (AF).^[1–3] Currently, various ablation strategies have been proposed for persistent AF based on CPVI, and while the targets and endpoints are poorly defined, the optimal ablation strategy for persistent AF is not yet well established.^[4,5]

Previous studies including 2 by our group showed that a pure linear ablation approach without CPVI could achieve a good short-term and medium-term maintenance of sinus rhythm (SR) in AF patients.^[6–9] The purpose of this study was to evaluate the long-term clinical outcome in persistent AF patients who underwent a pure linear ablation approach alone under the guidance of noncontact mapping aimed at a substrate modification of AF.

Table 1. Baseline Characteristics of the Cohort (n = 120)
Age, years	53.6 ± 10.3
Male, n (%)	94 (78.3%)
Amiodarone, n (%)	37 (30.8%)
Longstanding persistent AF, n (%)	48 (40%)
Median AF history, months	42.5 (9–160)
Median AF duration, months	9 (1–120)
Mean AF cycle length, ms	152.6 ± 12.5
Mean LA dimension, mm	41.6 ± 8.3
Patients with <40 mm, n (%)	66 (55%)
Patients with 40–50 mm, n (%)	50 (41.3%)
Patients with >50 mm, n (%)	4 (3.3%)
LVEF (%)	60.8 ± 4.2
Hypertension, n (%)	64 (53.3%)
Diabetes mellitus, n (%)	20 (16.7%)
Structural heart disease, n (%)	42 (35.0%)
Embolic events, n (%)	6 (5%)

AF = atrial fibrillation; LA = left atrium; LVEF = left ventricular ejection fraction.

Table 2. Comparison of Baseline Characteristics in Patients Whose AF Could (Termination) and Could Not (No Termination) Be Terminated by Ablation
	Termination (n = 75)	No Termination (n = 45)	P value
Age, years	53.9 ± 10.5	53.1 ± 10.0	0.672
Male, n (%)	61 (81.3%)	33 (73.3%)	0.303
Amiodarone, n (%)	24 (32.0%)	13 (28.9%)	0.721
Median AF history, months	48 (1–160)	38 (9–137)	0.181
Median AF duration, months	7 (1–70)	14 (1–120)	0.004
Mean AF cycle length, ms	153.1 ± 11.5	152.6 ± 14.2	0.546
LA dimension, mm	40.7 ± 4.3	43.2 ± 5.1	0.006
LVEF (%)	60.6 ± 4.3	61.1 ± 4.2	0.520
Hypertension, n (%)	37 (49.3%)	27 (60.0%)	0.257
Diabetes mellitus, n (%)	11 (14.7%)	9 (24.4%)	0.448
Structural heart disease, n (%)	28 (37.3%)	14 (31.1%)	0.489