[Efficacy and safety of segmental radiofrequency ablation for isolation of the superior vena cava in patients with atrial fibrillation].

Objective: To analyze the three-dimensional distribution of functional sinus node, right phrenic nerve and superior vena cava(SVC)-right atrial muscle sleeves by three-dimensional electrophysiological technique in patients with atrial fibrillation (AF), and to investigate the efficacy and safety of segmental radiofrequency catheter ablation (RFCA) for isolation of superior vena cava in these patients.Methods: In this retrospective study, we enrolled 136 AF patients who underwent first RFCA in the First Affiliated Hospital of Zhengzhou University from July 2018 to June 2019 and all patients underwent SVC isolation under sinus rhythm. Baseline clinical data of patients were collected. The functional sinus node was defined by activation mapping, pacing was guided by three-dimensional mapping (Carto) system, localization of the right phrenic nerve was defined by pacing map, the superior vena cava-right atrial muscle sleeves was determined according to the change of potential during SVC isolation, segmental RFCA was performed for SVC isolation, the three-dimensional distribution of functional sinus node, right phrenic nerve and superior vena cava(SVC)-right atrial muscle sleeves was determined by three-dimensional electrophysiological technique. Immediate SVC isolation was achieved in all patients. Patients were evaluated immediately after RFCA and patients were followed at 3, 6, 9, and 12 months after RFCA. Holter monitoring was performed every 3 months, the chest radiograph and the SVC ultrasonic examination were performed every 6 months after RFCA. Postoperative complications were assessed. Results: The mean age of the 136 patients with AF was (51.6±14.2) years, 86 (63.2%) were male, 98 cases (72.1%) were paroxysmal AF and 38 cases (27.9%) were persistent AF. Right atrium activation mapping revealed that 17 (12.5%) functional sinus node were located in the SVC, 78 (57.4%) were located at the SVC-right atrium junctions, 41 (30.1%) were located below the junction level. From the head to foot view, 83 (61.0%) functional sinus node were located at the anterior lateral segment of the SVC-right atrium three-dimensional reconstruction model, 34 (25.0%) located at the posterior lateral segment, 15 (11.0%) located at the anterior wall, 4 (2.9%) located at posterior wall or anterior septum. A total of 294 SVC muscle sleeves were detected among all patients, 94 (32.0%) SVC muscle sleeves were located at the anterior septum of the SVC-right atrium three-dimensional reconstruction model, 76 (25.9%) were located at the posterior septum, 21(7.1%) were located at the posterior free wall, 11 (3.7%) were located at the posterior lateral, 27 (9.2%) were located at anterior lateral wall and 65 (22.1%) were located at the anterior free wall. Right phrenic nerve positioned relatively fix, 133 (97.8%) were located at the lateral segment of the SVC-right atrium three-dimensional reconstruction model, 3 (2.2%) were located at the anterior free wall. Sinus rhythm and SVC isolation were successfully restored immediately after RFCA, no significant SVC stenosis, right phrenic nerve palsy and functional sinus node injury occurred immediately post procedure. All patients were followed up for (11.2±3.6) months and none had postoperative complication. Conclusions: Three-dimensional electrophysiological can determine the spatial location of functional sinus node, right phrenic nerve and SVC-right atrial sleeves. On this basis, segmental RFCA is a safe and effective method to achieve complete isolation of SVC.目的： 分析心房颤动（房颤）患者导管 三维电生理方法确定功能性窦房结、右侧膈神经及上腔静脉-右心房肌束的分布，探讨房颤节段性射频消融隔离上腔静脉的有效性和安全性。 方法： 本研究为回顾性研究，选取2018年7月至2019年6月于郑州大学第一附属医院首次行导管射频消融术并且接受上腔静脉隔离术的房颤患者为研究对象，收集患者的基线临床资料。所有患者均在窦性心律下行上腔静脉隔离，激动标测定位功能性窦房结，三维标测（Carto）系统指导下起搏、标测并定位右侧膈神经，根据上腔静脉隔离术中电位的变化确定上腔静脉-右心房肌束，节段性消融上腔静脉完成隔离，分析功能性窦房结、右侧膈神经及上腔静脉-右心房肌束的三维分布情况。术后即刻评估患者是否存在并发症（窦房结功能障碍、膈神经麻痹或上腔静脉狭窄），并在术后3、6、9、12个月进行门诊或电话随访，每3个月行动态心电图检查，每6个月行胸部透视和上腔静脉彩色多普勒超声检查，评估并发症发生情况。 结果： 136例房颤患者年龄（51.6±14.2）岁，男性86例（63.2%），阵发性房颤98例（72.1%），持续性房颤患者38例（27.9%）。17例（12.5%）患者功能性窦房结位于上腔静脉内，78例（57.4%）位于上腔静脉-右心房连接处，41例（30.1%）位于连接处以下水平；水平切面从头向足观，83例（61.0%）患者的功能性窦房结位于上腔静脉-右心房三维重建模型的前侧壁，34例（25.0%）位于后侧壁，15例（11.0%）位于前壁，其余4例（2.9%）位于后壁或前间隔；136例患者上腔静脉-右心房肌束总共为294条，其中94条（32.0%）位于上腔静脉-右心房三维重建模型的前间隔，76条（25.9%）位于后间隔，21条（7.1%）位于后游离壁，11条（3.7%）位于后侧壁，27条（9.2%）位于前侧壁，65条（22.1%）位于前壁；右侧膈神经位置比较固定，133例（97.8%）患者的膈神经位于上腔静脉-右心房三维重建模型的外侧壁，3例（2.2%）位于前壁。所有房颤患者术后均即刻成功恢复窦性心律和实现上腔静脉隔离，术后即刻无明显上腔静脉狭窄、膈神经麻痹及窦房结损伤。随访（11.2±3.6）个月，所有患者术后未出现并发症。 结论： 采用三维电生理方法能够确定功能性窦房结、右侧膈神经及上腔静脉-右心房肌束的空间分布规律，在此基础上进行节段性射频消融是完成上腔静脉隔离的安全有效的方法。.