[Safety and efficacy of high-power, short-duration superior vena cava isolation in combination with conventional radiofrequency ablation in patients with paroxysmal atrial fibrillation: a randomized controlled trial].

Objective: For patients with paroxysmal atrial fibrillation, superior vena cava isolation on the basis of pulmonary vein isolation may further improve the long-term success rate of radiofrequency ablation. We aimed to explore the efficacy and safety of superior vena cava isolation by high-power and short-duration (HPSD) ablation plus conventional radiofrequency ablation (RA) in patients with paroxysmal atrial fibrillation. Methods: It was a prospective randomized controlled study. From January 1, 2019 to June 1, 2020, 180 patients who underwent radiofrequency ablation for paroxysmal atrial fibrillation in our center were consecutively screened. Patients were eligible if there was a trigger potential and the muscle sleeve length was greater than 3 cm. A total of 60 eligible patients were finally included and randomly divided into HPSD group (HPSD plus RA) and common power and duration (CPD) group (CPD plus RA) by random number table method (n=30 in each group). Efficacy was evaluated by ablation points, isolation time and ablation time. Safety was evaluated by the incidence of POP, cardiac tamponade, phrenic nerve injury, sinoatrial node injury and all-cause. Results: Superior vena cava isolation was achieved by 14 (13, 15) points in the HPSD group, which was significantly less than that in the CPD group (20(18, 22), P<0.001). The superior vena cava isolation time was 8 (7, 9) minutes in the HPSD group, which was significantly shorter than in the CPD group (17(14, 20) minutes, P<0.001). The average ablation time significantly shorter in HPSD group than in CPD group (78.0(71.1, 80.0) s vs. 200(167.5, 212.5)s, P<0.001). The average impedance drop was more significant in the HPSD group than in the CPD group (20.00(18.75, 21.00)Ω (and the percentage of impedance drop was 15%) vs. 12.00(11.75, 13.25)Ω (the percentage of impedance decrease was 12%), P<0.001). There was 1 POP (3.3%) in the HPSD group, and 3 POPs (10.0%) in the CPD group (P>0.05). There was no cardiac tamponade, phrenic nerve injury, sinoatrial node injury and death in both groups. Conclusions: HPSD technique for the isolation of superior vena cava is safe and effective in patients with paroxysmal atrial fibrillation undergoing conventional radiofrequency ablation.目的： 探讨在肺静脉隔离的基础上，对于阵发性心房颤动（房颤）患者采用高功率短时程的消融方法进行上腔静脉隔离的安全性和有效性。 方法： 该研究为随机对照试验。连续纳入2019年1月1日至2020年6月1日因阵发性房颤行射频消融术的患者180例，对其中上腔静脉内伴有触发电位且肌袖长度≥3 cm者行上腔静脉隔离，最终纳入符合条件者60例，采用随机数表法将入选患者分入高功率组和常规功率组，每组30例。有效性观察指标包括消融点数、隔离时间、消融时间，安全性观察指标包括消融过程中发生的爆裂声（POP）、心脏压塞、膈神经损伤、窦房结损伤、全因死亡。 结果： 高功率组消融14（13，15）个点后达到了上腔静脉隔离，少于常规功率组的20（18，22）个点（P<0.001）。高功率组上腔静脉隔离时间为8（7，9）min，短于常规功率组的17（14，20）min（P<0.001）。高功率组消融放电时间为78.0（71.1，80.0）s，短于常规功率组的200.0（167.5，212.5）s（P<0.001）。高功率组阻抗下降20.00（18.75，21.00）Ω（阻抗下降百分比为15%），较常规功率组的12.00（11.75，13.25）Ω（阻抗下降百分比为12%）下降更为明显（P<0.001）。高功率组1例（3.3%）患者发生POP，常规功率组3例（10.0%），两组间差异无统计学意义（P>0.05）。两组患者均未发生心脏压塞、膈神经损伤、窦房结损伤和死亡。 结论： 采用高功率短时程的消融方法对于阵发性房颤患者进行上腔静脉隔离安全、有效。.