Treat Atrial Flutter
Da Costa A, Thévenin J, Roche F, et al. Results from the Loire-Ardèche-Drôme-Isère-Puy-de-Dôme (LADIP) trial on atrial flutter, a multicentric prospective randomized study comparing amiodarone and radiofrequency ablation after the first episode of symptomatic atrial flutter. Circulation. 2006;114:1676-1681.
Radiofrequency ablation (RFA) has high success rates in atrial flutter, and American College of Cardiology/American Hospital Association guidelines classify a first episode of well-tolerated atrial flutter as a class IIa indication for RFA treatment. The LADIP trial compared RFA with the current practice of electroosmotic flow (EOF) cardioversion plus amiodarone after a first episode of symptomatic atrial flutter.
One hundred and four consecutive patients with a documented first episode of atrial flutter were enrolled over a period of 39 months. Excluded from the study were patients under the age of 70, those who had had previous antiarrythmic treatment for atrial flutter, those who had an amiodarone contraindication, patients with New York Heart Association class IV heart failure, and those who had a history of heart block. All 52 patients in group I received RFA by a standard method. Fifty-one of the 52 patients in group II underwent intracardiac stimulation, followed, if necessary, by external or internal cardioversion. All patients in group II received amiodarone as well as vitamin K antagonists.
The patients were followed up in the outpatient department at one, three, six, 12, and 18 months after randomization and at the end of the study. At each visit, arrhythmic or cardiovascular events were recorded, and a 12-lead ECG was obtained. Patients were fitted with a Holter monitor for seven days if they had recurring palpitations or symptoms. The primary outcome studied was recurrence of symptomatic atrial flutter and occurrence of atrial fibrillation.
After a mean follow-up of 13+/-6 months, atrial flutter recurred in two of the 52 (3.8%) patients in group I and 15 of 51 (29.5%) patients in group II (P<0.0001). In group I, one patient required a second, successful ablation. All the patients who recurred in group II were successfully treated using RFA. The occurrence of significant symptomatic atrial fibrillation was 8% in both groups at the end of the first year. By the end of the study, two patients in group I and one patient in group II were in chronic atrial fibrillation. When all the episodes of atrial fibrillation were counted (including those patients whose episodes lasted <10 minutes but were documented with an event monitor), the groups did not differ significantly.
No procedure-related complications occurred in group I. In the amiodarone group, however, two patients developed hypothyroidism, one developed hyperthyroidism, and two patients had symptomatic sick sinus syndrome. There were a total of 14 deaths during the course of the study (six patients in group I and eight patients in group II); none were related to the study protocol.
This study is the largest to date showing the superiority of RFA to cardioversion plus amiodarone after the first episode of symptomatic atrial flutter. The long-term risk of subsequent atrial fibrillation was found to be similar to that of the amiodarone-treatment group. Because the mean age of patients in this study was 78, however, these findings cannot necessarily be extrapolated to younger patient populations. Further, oral amiodarone was used initially in this study. It can be argued that IV amiodarone is far more efficacious than oral forms in the acute setting. Because RFA is an invasive procedure, it is user-dependent and may be unfeasible in different care settings. Also, RFA might not be as appropriate for many symptomatic patients with atrial flutter and hemodynamic instability. Nevertheless, this study presents hospital-based physicians with an additional consideration in the acute care setting for patients with a first episode of atrial flutter.