Weber T F, Klemm H, Koops A, Nagel H-D, Willems S, Adam G, Begemann P G
Abteilung Radiologie, Deutsches Krebsforschungszentrum, Heidelberg.
Rofo. 2007 Dec;179(12):1264-71. doi: 10.1055/s-2007-963570. Epub 2007 Nov 14.
Detailed anatomic information of the left atrium is necessary for securely performing radiofrequency ablation of atrial fibrillation-triggering ectopies in the pulmonary vein ostia. In this study the impact of a preinterventionally acquired cardiac computed tomography (CT) on pulmonary vein isolation (PVI) was assessed.
Examinations of 54 patients with paroxysmal atrial fibrillation undergoing PVI were analyzed. In 27 patients a supplementary cardiac CT was obtained prior to PVI (CT group, 12 women, 15 men, 59.7+/-9.9 years of age): 16 x 1.5 mm collimation, 0.2 pitch, 120 kV tube voltage, 400 effective mAs. The fluoroscopy time, effective dose and quantity of radiofrequency (RF) pulses of the following catheter ablation were compared to 27 patients undergoing stand-alone PVI (11 women, 16 men, 62.0+/-9.9 years of age). Mann-Whitney tests served for statistical comparison.
CT datasets were successfully integrated into the ablation procedure of each patient in the CT group. The mean quantity of RF pulses was significantly lower in the CT group (22.1+/-8.0 vs. 29.1+/-11.9, p=0.030), and a significant reduction of fluoroscopy time was found (41.8+/-12.0 min vs. 51.2+/-16.0 min, p=0.005). Effective doses of the catheter ablation differed in an equivalent dimension but altogether not significantly (14.9+/-10.0 mSv vs. 20.0+/-16.0 mSv, p=0.203). The mean additive effective dose of the cardiac CT was 8.5+/-0.3 mSv.
CT-guided ablation of atrial fibrillation requires less fluoroscopy time than stand-alone PVI. Due to the multi-faceted dependency of individual fluoroscopy doses, a consistent reduction of the effective dose was not observed. Since supplementary CT constitutes an additive dose, optimized CT atriography needs to be designed in order to provide sufficient image quality while reducing X-ray exposure. The reduction in RF pulses implies an increase in the effectiveness and safety of catheter ablation.
要安全地对肺静脉口触发房颤的异位兴奋灶进行射频消融，左心房的详细解剖信息是必要的。在本研究中，评估了干预前获取的心脏计算机断层扫描（CT）对肺静脉隔离（PVI）的影响。
分析了54例接受PVI的阵发性房颤患者的检查情况。27例患者在PVI之前进行了补充心脏CT检查（CT组，12名女性，15名男性，年龄59.7±9.9岁）：准直16×1.5mm，螺距0.2，管电压120kV，有效毫安秒400。将后续导管消融的透视时间、有效剂量和射频（RF）脉冲数量与27例接受单纯PVI的患者（11名女性，16名男性，年龄62.0±9.9岁）进行比较。采用曼-惠特尼检验进行统计学比较。
CT组中，CT数据集成功整合到每位患者的消融过程中。CT组的平均RF脉冲数量显著更低（22.1±8.0对29.1±11.9，p = 0.030），且透视时间显著缩短（41.8±12.0分钟对51.2±16.0分钟，p = 0.005）。导管消融的有效剂量在同等维度上有所不同，但总体上无显著差异（14.9±10.0mSv对20.0±16.0mSv，p = 0.203）。心脏CT的平均附加有效剂量为8.5±0.3mSv。
与单纯PVI相比，CT引导下的房颤消融所需透视时间更少。由于个体透视剂量存在多方面依赖性，未观察到有效剂量持续降低。由于补充CT构成附加剂量，需要设计优化的CT心房造影，以便在降低X线暴露的同时提供足够的图像质量。RF脉冲减少意味着导管消融的有效性和安全性提高。
