Cryoballoon Pulmonary Venous Isolation in Patients Referred for Typical Atrial Flutter Ablation (PAF CRIOBLAF)

Prevention of Atrial Fibrillation by Combined Right Isthmus Ablation and cryoBalloon Pulmonary Vein Isolation in Patients With Typical Atrial Flutter

- Background: Atrial fibrillation is frequently associated with typical atrial flutter in clinical practice. If the radical treatment of atrial flutter by radiofrequency catheter is achieved in most cases without recurrence, it does not prevent the occurrence of atrial fibrillation that occurs in about 70% of these patients after several years of follow-up. However, the latter arrhythmia is associated with significant morbidity and mortality. The problem of atrial fibrillation occurrence after successful ablation of typical atrial flutter remains physicians primary concern in monitoring these patients. Objectives: The purpose of this study is to demonstrate that the pulmonary veins isolation using balloon cryotherapy technology performed at the time of flutter ablation, significantly reduces the risk of developing atrial fibrillation in the two year period following the procedure. Selection Criteria: Patients referred for ablation of typical atrial flutter with an history of at least one documented episode of atrial fibrillation (atrial flutter remaining the predominant arrhythmia)will be enrolled in the study. Study Methods: This is a prospective, multicenter, randomized, 2-arms study, comparing the rate of atrial fibrillation occurrence over a two years period following either an ablation procedure of typical atrial flutter (Group 1), or a combined procedure of typical atrial flutter ablation and pulmonary veins cryoballoon isolation (Group 2). The enrollment period will be of 18 months. Randomization will be 1:1 and will be balanced in blocks of varying size. Patients will then be regularly followed up clinically and by long-term ECG recordings. Evaluation Criteria: The primary endpoint will be the recurrence of symptomatic or asymptomatic atrial fibrillation, documented by an ECG or an R-test, occurring between M3 and M24 Number of patients: 170 patients will be enrolled in the study Number of centers: Four French and three German centers will participate. Perspective: The demonstration of a clinical benefit in terms of atrial fibrillation risk reduction in the patient group with pulmonary vein isolation, could lead to a modification of atrial arrhythmia treatment indication.

Main endpoint will be the recurrence of symptomatic or asymptomatic atrial fibrillation as documented by an ECG or a R-test. Sustained AF episodes of more than a minute will be classified depending if they are symptomatic or not.

Occurrence rate of atypical flutter defined as a continuous atrial activity (with no return to the isoelectric line)in at least one lead, whose ECG appearance of F waves is different from that of a typical flutter

Rate of occurrence of atrial tachycardia defined as an atrial activaty that generates a P wave with return to the isoelectric line in all leads

The following complications will be considered: Hematoma at punction site, Thromboembolic accident, Tamponnade, Phrenic nerve paralysis, Symptomatic stenosis of pulmonary vein, Atrio-ventricular block Atrioesophageal fistula

Rate of major cardiovascular events such as rehospitalization for arrhythmia, heart failure, or embolic accident

Inclusion Criteria: Patient with a spontaneous flutter or with a flutter recurrence when it was not considered appropriate to use a preventive treatment so far. The flutter may have been paroxysmal or may still be present. Patient with at least one documented episode of typical flutter defined as follows: negative F waves in the inferior territory, positive in V1 and negative in V6 lead, F wave pattern with characteristic "saw tooth" appearance and finally a heart rate comprised between 240 and 320 beats per minute. Patient with effective anticoagulant therapy for at least 3 weeks. Patient with at least one episode of AF (lasting more than 1 minute) documented on an ECG or a 24 hour Holter recording Patient who signed an informed consent. Patient with age ≥ 18 yo and ≤ 75 yo Exclusion Criteria: Patients with the following characteristics will be excluded: Contraindication to right-heart catheterization Contraindication to an anticoagulant treatment Patient for which AF is predominant (more recordings of AF than Flutter) Persistent AF at the time of inclusion visit History of mitral valve surgery Known disorders of blood clotting Cardiothyreosis Life expectancy < 24 months Less than 18 years old and pregnant ladies. As before any ablation, a pregnancy test will be done the day before or the day of the procedure Patient less than 18 years old Patient under guardianship Patient deprived of their liberty by a court decision