Atrial Fibrillation After Radiofrequency Ablation of Type I Atrial Flutter

Abstract

Background-The occurrence of atrial fibrillation after ablation of type I atrial flutter remains an important clinical problem. To gain further insight into the pathogenesis and significance of postablation atrial fibrillation, we examined the time to onset, determinants, and clinical course of atrial fibrillation after ablation of type I flutter in a large patient cohort. Methods and Results-Of 110 consecutive patients with ablation of type I atrial flutter, atrial fibrillation was documented in 28 (25%) during a mean follow-up of 20.1Ϯ9.2 months (cumulative probability of 12% at 1 month, 23% at 1 year, and 30% at 2 years). Among 17 clinical and procedural variables, only a history of spontaneous atrial fibrillation (relative risk 3.9, 95% confidence intervals 1.8 to 8.8, Pϭ0.001) and left ventricular ejection fraction Ͻ50% (relative risk 3.8, 95% confidence intervals 1.7 to 8.5, Pϭ0.001) were significant and independent predictors of subsequent atrial fibrillation. The presence of both these characteristics identified a high-risk group with a 74% occurrence of atrial fibrillation. Patients with only 1 of these characteristics were at intermediate risk (20%), and those with neither characteristic were at lowest risk (10%). The determinants and clinical course of atrial fibrillation did not differ between an early (Յ1 month) compared with a later onset. Atrial fibrillation was persistent and recurrent, requiring long-term therapy in 18 patients, including 12 of 19 (63%) with prior atrial fibrillation and left ventricular dysfunction. Conclusions-Atrial fibrillation after type I flutter ablation is primarily determined by the presence of a preexisting structural and electrophysiological substrate. These data should be considered in planning postablation management. The persistent risk of atrial fibrillation in this population also suggests a potentially important role for atrial fibrillation as a trigger rather than a consequence of type I atrial flutter. (Circulation. 1998;98:315-322.)

Contemporary Management of Atrial Flutter

“…25,26 In patients with episodes of both AFl and AF, flutter ablation may have different effects on the incidence of AF. [27][28][29] Nabar et al 30 noted a marked reduction in AF episodes after flutter ablation in patients with AFl as their dominant arrhythmia. This was not observed when AF occurred more often than AFl.…”

Randomized Comparison of Anatomic and Electrogram Mapping Approaches to Ablation of Typical Atrial Flutter

“…1 ,2 ,8 Another technique used has been pullback of the ablation catheter along the cavotricuspid isthmus during continuous application of energy. 3 -7 Although the two techniques have not been directly compared, similar results have been reported with both [1][2][3][4][5][6][7][8] ; therefore, it is unlikely that either technique has a major advantage over the other. In this study, discrete applications of energy were used to facilitate comparison of the anatomic and the electrogram mapping approach using a uniform endpoint of 15 applications with both techniques.…”

Atrial Flutter, Typical and Atypical: A Review

“…38, [104][105][106] More recent reports have reported even higher incidences of AF. in a significant reduction in AF recurrence in patients whether or not they undergo AF ablation, [113][114][115][116] and this may be applicable to flutter given the very similar risk factor profiles.…”