using cryoballoon ablation as initial treatment for persistent atrial fibrillation

Conditions: Atrial Fibrillation, Persistent; Arrhythmias, Cardiac

Summary: this study is to assess the effectiveness and safety of using cryoballoon ablation comparing with anti-arrhythmic drug therapy as initial treatment for naive patients with persistent atrial fibrillation.

subjects with persistent atrial fibrillation with no history of treatment with anti-arrhythmic drugs are randomized 1:1 to either an anti-arrhythmic drug or pulmonary vein isolation using the cryoballoon catheter.

Eligibility criteria:
inclusion criteria: * documentation of symptomatic persistent af: defined as having a continuous episode lasting longer than 7 days but less than 1 year documented by consecutive ecg recordings or defined as having a continuous episode lasting longer than 7 days but less than 1 year documented by an ecg recording and one doctor note indicating patient had symptoms consistent with af * age 18 -75 years old * structurally normal heart with lvef ≥50%, interventricular septum thickness ≤ 12 mm, and left atrial diameter \<46 mm (short axis) as obtained by transthoracic echocardiography. • * normal ecg parameters when measured in sinus rhythm (qrs width ≤120 ms in a 12-channel surface ecg, qtc interval \<440 ms, and pq interval ≤210 ms). exclusion criteria: * history of af treatment with class i or iii antiarrhythmic drug, including sotalol, with the intention to prevent an af recurrence. however, patients pretreated with above aad for less than 7 days with the intention to convert an af episode are allowed. * left atrial ablation or surgical procedure (including left atrial appendage closures) * presence or likely implant of a permanent pacemaker, biventricular pacemaker, loop recorder, or any type of implantable cardiac defibrillator (with or without biventricular pacing function) within 12 months * presence of any pulmonary vein stents * presence of any pre-existing pulmonary vein stenosis * pre-existing hemidiaphragmatic paralysis * presence of any cardiac valve prosthesis * +3 and +4 mitral valve regurgitation or stenosis * any cardiac surgery, myocardial infarction, percutaneous coronary intervention (pci) / percutaneous transluminal coronary angioplasty (ptca) or coronary artery stenting which occurred during the 3 month interval preceding e consent date * unstable angina * new york heart association (nyha) class ii, iii or iv congestive heart failure * primary pulmonary hypertension * rheumatic heart disease * thrombocytosis, thrombocytopenia * any condition contraindicating chronic anticoagulation * active systemic infection * hypertrophic cardiomyopathy * cryoglobulinemia * uncontrolled hyperthyroidism * any cerebral ischemic event (strokes or transient ischemic attacks (tias)) which occurred during the 6 month interval preceding the consent date * any woman known to be pregnant or breastfeeding. * life expectancy less than one year * current or anticipated participation in any other clinical trial of a drug, device or biologic during the duration of the study not pre-approved by medtronic * active intracardiac thrombus * known drug or alcohol dependency * unwilling or unable to comply fully with study procedures and follow-up * significant chronic kidney disease-estimated glomerular filtration rate(ckd-egfr) \<30umol/l

Keywords: cryoablation pulmonary vein isolation atrial fibrillation anti-arrhythmic agents