Surgical Ablation of Permanent Atrial Fibrillation: Age, LV Dilatation, Obesity.

OBJECTIVES: Although concomitant surgical ablation can help to reach freedom from atrial fibrillation (FREEAF) even in patients with permanent atrial fibrillation (AF), some cardiac surgeons hesitate to perform concomitant ablation to avoid perioperative risk escalation. Here, we investigated outcome and predicators of therapeutic success of concomitant surgical ablation in an all-comers study. METHODS: Ablation-naïve patients with formerly accepted permanent AF (FAP, n = 41) or paroxysmal AF (parAF, n = 24) underwent concomitant epicardial bipolar radio frequency ablation and implantable loop recorder (ILR) at two surgical departments. Follow-up examination for 24 months included electrocardiogram, ILR readout, 24h Holter monitoring, echocardiography, and blood sampling. RESULTS: Eighty-six percent of parAF and 70% of FAP patients reached FREEAF (month 24). Mortality was low (parAF/FAP: 5.3 ± 0.2%/4.1 ± 0.3%; p < 0.05; EuroScoreII; 6.1 ± 0.7%/6.4 ± 0.4%, p = ns) and no strokes occurred. FREEAF induced atrial reverse remodeling (left atrial [LA] diameter: -6.7 ± 2.2 mm) and improved cardiac function (left ventricular ejection fraction [LVEF]: +7.3 ± 2.8%), while AF resulted in further atrial dilation (+8.0 ± 1.0 mm, p < 0.05) and LVEF reduction (-7.0 ± 1.3%, p < 0.05). Higher LV (odds ratio [OR]: 1.164) and LA diameter (OR: 1.218), age (OR: 1.180) and body mass index (BMI) (OR: 1.503) increased the risk factors of AF recurrence. Patients remaining in sinus rhythm (SR) demonstrated a decrease in BMI, while AF recurrence was associated with stable overweight. Further aging did not reduce FREEAF. CONCLUSIONS: Long-term SR is achievable by concomitant surgical ablation even in FAP patients. Therefore, it should be offered routinely. Obesity influences therapeutic long-term success but may also offer addressable therapeutic targets to reach higher FREEAF rates.

The Same is Not the Same: Device Effect during Bipolar Radiofrequency Ablation of Atrial Fibrillation.

BACKGROUND: Different ablation devices deliver the same type of energy but use individual control mechanisms to estimate efficacy. We compared patient outcome after the application of radiofrequency ablation systems, using temperature- or resistance-control in paroxysmal and persistent atrial fibrillation (AF). METHODS: This is an unselected all-comers study. Patients underwent standardized left atrial (paroxysmal atrial fibrillation, [PAF] n = 31) or biatrial ablation (persistent atrial fibrillation [persAF] n = 61) with bipolar RF from October 2010 to June 2013. Patients with left atrial dilatation (up to 57 mm), reduced left ventricular (LV) function, and elderly were included. We used resistance-controlled (RC) or temperature-controlled (TC) devices. We amputated atrial appendices and checked intraoperatively for completeness of pulmonary vein exit block. All patients received implantable loop recorders. Follow-up interval was every 6 months. Antiarrhythmic medical treatment endured up to month 6. RESULTS: We reached 100% freedom from atrial fibrillation (FAF) in PAF. In perAF 19% of the RC but 82% of the TC patients reached FAF (12 months; p < 0.05). TC patients exhibited higher creatine kinase-muscle/brain (CK-MB) peak values. In persAF, CK-MB-levels correlated to FAF. No and no mortality (30 days) was evident. Twelve-month mortality did not correlate to AF type, AF duration, LV dimension, or function and age. Prolonged need of oral anticoagulants was 90.1% (RC) and 4.5% (TC). CONCLUSION: In patients with persAF undergoing RF ablation, TC reached higher FAF than RC. Medical devices are not "the same" regarding effectiveness even if used according to manufacturer's instructions. Thus, putative application of "the same" energy is not always "the same" efficacy.