Abstract 3527: Intraoperative Cooled-Tip Radiofrequency Linear Atrial Ablation to Treat Permanent Atrial Fibrillation
Atrial fibrillation (AF) surgery has become more engaged in every-day practise of cardio-surgical centres. The cut-and-sew technique still remains the gold standard with superior efficacy. Is an concomitant intraoperative approach using cooled-tip endocardial radiofrequency energy to induce linear atrial lesions (SICTRA) safe and effective in treating AF?
Methods: 222 patients (mean EUROSCORE 6.4, AF duration 7years) presenting with permanent AF (>1 year, 1 failed cardioversion) and the need for cardiac surgery were included. In addition to the cardio-surgical procedure concomitant SICTRA was performed. In 116 patients the ablation pattern was restricted to the left atrium alone. Follow-up constituted of ECG, holter-ECG and Doppler echocardiography.
Results: Cardio-surgical procedures were mitral valve surgery in 94, aortic valve replacement in 29, bypass surgery in 76 including 24 patients with additional mitral valve surgery and combined procedures in 23. During the mean follow-up of 29months 174 patients (78%) converted to sinusrhythm (SR) without postoperative antiarrhythmic medication. At discharge (0.5months post operatively) 30%, at 3 months 62%, at 6 months 76% and after 12 months 75% of patients were in stable SR. Biatrial contraction was documented in 82% of patients in SR. In patients with a SICTRA procedure restricted to the left atrium conversion rates were not different compared to a biatrial approach (80% versus 78%, p=0.47). The type of cardio-surgical procedure did not influence conversion. 30-day-mortality was found to be 4% (9/222). Histopathology revealed 24% of all lesions to be histologically non-transmural but only 4% of patients developed sustained regular atrial arrhythmia (2% of all patients with incisional tachycardia.
Conclusions: SICTRA safely and effectively restores stable sinusrhythm in 78% of patients with permanent AF undergoing open heart surgery. A biatrial contraction can be restored in 82% of these patients. Rhythm conversion is not influenced by treatment of the right atrium or the performed cardio-surgical procedure. Sustained regular atrial arrhythmia with the need for invasive treatment strategies occur in 4% although intraoperative ablation lesions are often non-transmural.