Linear lesions for treating the recurrence of persistent atrial tachyarrhythmia after cryoballoon ablation of atrial fibrillation.

BACKGROUND: There is no consensus on the most effective radiofrequency ablation strategy for the initial or repeated treatment of persistent atrial tachyarrhythmia (ATa). OBJECTIVE: To describe success and complication rates after the creation of left atrial (LA) linear lesions for recurrent persistent ATa following an index cryoballoon pulmonary vein isolation (PVI), and to identify predictors of ATa recurrence. METHODS: During March 2013 to March 2020, we prospectively included all consecutive patients undergoing repeat procedures for the treatment of persistent ATa. Radiofrequency ablation consisting of the creation of linear lesions: a roofline, a mitral isthmus and/or septal line, and a cavotricuspid isthmus line. All patients were prospectively followed up for ATa recurrence. RESULTS: Overall, 133 patients underwent 170 procedures after initial cryoballoon PVI (n=715). At least one pulmonary vein reconnection was observed in 60 patients (45.1%), all of whom underwent successful re-disconnection. After all the procedures, >90% of patients had a lesion pattern consisting of a roofline, a mitral isthmus and/or septal line, and a cavotricuspid isthmus line. ATa was terminated in 41 patients (35%). There were three cases of tamponade (3/170 procedures, 1.8%). Ninety-two patients (69.2%) were in sinus rhythm after a median (interquartile range) of 36 (21-53) months since the index cryoballoon PVI. Diagnosis-to-ablation time and LA area were predictors of recurrence in multivariable analysis. CONCLUSION: The creation of linear lesions is a safe and effective treatment strategy for the recurrence of persistent ATa after cryoballoon PVI. Longer diagnosis-to-ablation time and larger LA area were predictive of ATa recurrence.

Single-catheter simplified stepwise approach to persistent atrial fibrillation ablation: A feasibility study.

BACKGROUND: The strategy for atrial fibrillation ablation in persistent atrial fibrillation remains controversial. A single-catheter approach was recently validated for pulmonary vein isolation. AIM: To evaluate the feasibility of this approach to performing persistent atrial fibrillation ablation, including pulmonary vein isolation and atrial lines, if needed. METHODS: We prospectively included 159 consecutive patients referred to our centre for a first persistent atrial fibrillation ablation between January 2018 and December 2018. All patients underwent pulmonary vein isolation. If the patient was still in atrial fibrillation (spontaneously or inducible), we subsequently performed a stepwise approach, including roof line, anterior mitral line, posterior box lesion and cavotricuspid isthmus line. Finally, if patient remained in atrial fibrillation at the end of the procedure, a synchronized direct-current cardioversion was applied to restore sinus rhythm. RESULTS: At baseline, 54 patients were in sinus rhythm and underwent pulmonary vein isolation. For patients in atrial fibrillation, after pulmonary vein isolation and ablation of additional lines, if needed, 18 patients were converted to atrial tachycardia and one directly to sinus rhythm; 96 were still in atrial fibrillation and underwent direct-current cardioversion. After a mean follow-up of 17±6 months, 57 patients (36%) experienced atrial arrhythmia recurrence. No deaths, tamponades or phrenic nerve injuries were observed following the procedure. The main mode of arrhythmia recurrence was atrial fibrillation in 75% of cases and atrial tachycardia in 25% of cases. CONCLUSION: A single-catheter approach, including pulmonary vein isolation and atrial lines, is feasible and safe in patients undergoing persistent atrial fibrillation ablation, with an acceptable success rate of 64% at mid-term follow-up.

Persistent atrial fibrillation presenting in sinus rhythm: pulmonary vein isolation versus pulmonary vein isolation plus electrogram-guided ablation.

BACKGROUND: The classification of atrial fibrillation as paroxysmal or persistent (PsAF) is clinically useful, but does not accurately reflect the underlying pathophysiology and is therefore a suboptimal guide to selection of ablation strategy. AIM: To determine if additional substrate ablation is beneficial for a subset of patients with PsAF, in whom long periods of sinus rhythm (SR) can be maintained. METHODS: We included patients presenting with PsAF in whom continuous periods of SR>3months were documented. All patients were in SR on the day of the procedure. Electrical pulmonary vein isolation (PVI) was performed in all patients. Additional electrogram (EGM)-guided ablation was left to the discretion of the operator. Patient characteristics and follow-up were analysed with respect to presence or absence of additional EGM-guided ablation. RESULTS: Sixty-five patients (mean age 60.1±8.9years; 81.5% men) met the inclusion criteria. EGM-guided ablation was performed in 32 (49%) patients. Patients with and without EGM-guided ablation had similar baseline characteristics. Absence of EGM-guided ablation was one of the independent predictors for arrhythmia recurrences after the index procedure (hazard ratio 0.24; confidence interval 0.12-0.47). After a median follow-up of 18±10months, the number of procedures required was significantly higher in the 'PVI-only' group (2.24±0.75 vs. 1.84±0.81; P=0.04) to achieve a similar success rate (84% vs. 81%; P=0.833). CONCLUSION: The addition of EGM-guided ablation requires fewer procedures to achieve similar clinical efficacy in mid-term follow-up compared with a PVI-only strategy in patients with PsAF presenting for ablation in SR.