Page 34 - ADD-ON ABLATION SURGERY IN PATIENTS WITH ATRIAL FIBRILLATION

Chapter 2
Methods
Study Design
The main study is a prospective, randomised, clinical, multicentre trial, comprising 150 patients enrolled to compare rhythm outcome, morbidity and mortality in two treatment strategies for patients with AF undergoing valvular and/or coronary surgery.This health related quality of life study was part of the main trial, in which 132 of the 150 patients completed a minimum of one out of three postoperative questionnaires during total follow-up (147 patients completed the pre-operative questionnaire). Patients were randomly assigned to ‘surgery as usual’ or ‘add-on arrhythmia surgery’, by a computerized randomisation program on the day before surgery.To assure an equal distribution of patients undergoing valvular and/or coronary surgery in both treatment arms, patients were stratified after inclusion but before randomisation. Patients and all medical personnel (with exception of the surgical team) were blinded to their group assignment. All AF patients undergoing cardiac surgery, who were admitted to the University hospital Maastricht or to Amphia hospital Breda in the period from October 2002 up till November 2005, were considered for inclusion in the main trial. Patients had a history of documented paroxysmal or persistent AF for at least three months prior to surgery as defined by the ACC/AHA/ESC guidelines10. Patients with sick sinus syndrome or contraindications for oral anticoagulant agents were excluded from the study. HrQoL and maintenance of SR at 1-year follow-up after surgery, as stated on the outpatients visit and measured on an EKG and 24-hour Holter registration, were considered as primary end points of the total study.This sub-study hypothesized that add-on surgery would improve HrQoL.The process mechanism in the hypothesis is that long-term morbidity associated with AF, would be reduced in the add-on surgery group as compared to the ‘surgery as usual’ group and therefore would enhance HrQoL.
Add-on arrhythmia surgery procedure
The surgical ablation procedure was performed first before institution of cardiopulmonary bypass allowing epicardial off-pump beating heart ablation. Temporary epicardial pacing wires were positioned at the transition of the right pulmonary veins to the left atrium or at the roof of the left atrium as reached from within the transverse sinus to assure positioning within the area to be isolated. Additional pacing wires were put close to the interventricular
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