Long term outcome of cavotricuspid isthmus cryoablation for the treatment of common atrial flutter in 180 patients: A single center experience

Abstract

Objective Recent literature has shown that common type atrial flutter (AFL) can recur late after cavotricuspid isthmus (CTI) catheter ablation using radiofrequency energy (RF). We report the long term outcome of a large group of patients undergoing CTI ablation using cryothermy for AFL in a single center. Methods Patients with AFL referred for CTI ablation were recruited prospectively from July 2001 to July 2006. Cryoablation was performed using a deflectable, 10.5 F, 6.5 mm tip catheter. CTI block was reassessed 30 min after the last application during isoproterenol infusion. Recurrences were evaluated by 12-lead ECG and 24 h Holter recording every clinic visit (1/3/6/9 and 12 months after the procedure and yearly thereafter) or if symptoms developed. Results The 180 enrolled patients had the following characteristics: 39 women (22%), mean age 58 years, no structural heart disease in 86 patients (48%), mean left atrium diameter 44±7 mm and mean left ventricular ejection fraction 57±7%. The average number of applications per patient was 7 (3 to 20) with a mean temperature and duration of −88°C and 3 min, respectively. Acute success was achieved in 95% (171) of the patients. There were no complications. After a mean follow-up of 27±17 (from 12 to 60) months, the chronic success rate was 91%. The majority of the recurrences occurred within the first year post ablation. One hundred and twenty three patients had a history of atrial fibrillation (AF) prior to CTI ablation and 85 (69%) of those remained having AF after cryoablation. In 20 of 57 (35%) patients without a history of AF prior to CTI ablation, AF occurred during follow-up. Conclusions This prospective study showed a 91% chronic success rate (range 12 to 60 months) for cryoablation of the CTI in patients with common type AFL and ratified the frequent association of AF with AFL.

Efficacy comparison between cryoablation and radiofrequency ablation for patients with cavotricuspid valve isthmus dependent atrial flutter: a meta-analysis

“…As a reasonably alternative energy source, cryoablation had not only been demonstrated to be an effective approach but also minimized the risk of cardiovascular events 7 16 . In a large 160 patients pivotal study conducted by Feld and his colleagues, 87.5% patients referred for cryoablation achieved acute success and 80.3% patients, who completed 6 months follow-up, maintained sinus rhythm 17 . Moreover, another single center study enrolled 180 patients also showed high acute and chronic success rate which were identical to radiofrequency ablation 18 .…”

Atrial fibrillation inducibility during cavotricuspid isthmus-dependent atrial flutter ablation as a predictor of clinical atrial fibrillation. A meta-analysis

“…Typical cavotricuspid isthmus (CTI)-dependent AFL is characterized by successful cure by RFA and low risk of recurrence. [1][2][3][4][5][6][7][8][9][10] However, AF occurs in 15 to 82% of patients by 6 to 40 months after AFL ablation. 6,8,9,[11][12][13][14][15] Notably, despite having a 6% cumulative incidence of embolic stroke during mean follow-up of 30 months after ablation for CTI AFL, there are scant recommendations for anticoagulation for this population.…”

“…[1][2][3][4][5][6][7][8][9][10] However, AF occurs in 15 to 82% of patients by 6 to 40 months after AFL ablation. 6,8,9,[11][12][13][14][15] Notably, despite having a 6% cumulative incidence of embolic stroke during mean follow-up of 30 months after ablation for CTI AFL, there are scant recommendations for anticoagulation for this population. 16,17 The progressive occurrence of AF after AFL ablation has been associated with numerous factors including advanced age, female sex, BMI, prior history of AF, left atrial enlargement (LAE), reduced left ventricular ejection fraction (LVEF), treatment with antiarrhythmic drugs (AAD) before ablation, mitral regurgitation and AF inducibility.…”