[Electrophysiological characteristics and therapeutic efficacy of radiofrequency ablation of focal atrial tachycardia originating from the right atrial appendage during pregnancy].

Objective: To analyze the electrophysiological characteristics and the therapeutic efficacy of irrigated-tip catheter radiofrequency ablation(RFA) without radiation for pregnant women with focal atrial tachycardia(AT) originating from the right atrial appendage (RAA). Methods: Data from 55 women with focal AT, who underwent radiofrequency ablation (RFA) in the First Affiliated Hospital of Zhengzhou University from October 2016 to March 2019, were screened. 2 non-pregnant women with right atrial appendage tachycardia (RAAT) and 4 pregnant women with non-RAAT were excluded. The remaining 49 cases were divided into RAAT during pregnancy group (n=6, including 4 cases of tachycardia-induced cardiomyopathy) and non-pregnant and non-RAAT group (control, n=43). Under the guidance of three-dimensional mapping system, the earliest activation site was identified, RFA with the irrigated catheter without x-ray fluoroscopy was performed in RAAT patients during pregnancy, all patients in control group underwent non-zero-ray ablation. Patients were followed up at 3, 6, 12 months post procedure, and yearly follow up thereafter in outpatient clinic. Electrocardiogram or Holter monitoring was performed during follow up. AT recurrence and surgical complications were recorded during follow up. At 6 months after RFA, echocardiography examination and laboratory examination including N-terminal B-type brain natriuretic peptide measurement were performed in the pregnant patients, delivery results were also recorded in the pregnant patients. The electrophysiological characteristics of RAAT during pregnancy were analyzed, the therapeutic efficacy of RFA was compared between the two groups. Results: This study is a retrospective study. Age ((30.7±6.2)years vs. (57.2±11.7)years), left ventricular ejection fraction ((46.0±12.8)% vs. (60.1±5.9)%), proportions of organic heart disease (0% vs. 58%) were significantly lower in the RAAT patients during pregnancy group than in control group (P<0.05), while proportions of patients with persistent tachycardia (100% vs. 7%), symptoms of chest distress and palpitation (6/6 vs. 49%) and left ventricular ejection farction≤50% (4/6 vs. 9%) were significantly higher in RAAT group than in control group (P<0.05), heart rate was similar between the two groups ((163.7±11.1)beats/minutes vs. (153.7±15.2)beats/minutes, P>0.05). The characteristic P-wave morphology was observed in RAAT patients during pregnancy, i.e, P wave was mostly upright (5/6) in inferior-leads (Ⅱ, Ⅲ, aVF) and in lead I and aVL, deep and wide negative P wave was found in V1 lead (5/6), and gradually became positive from V2-V6. The mean tachycardia cycle length was (361.7±38.5) ms. Three-dimensional mapping showed that the origin points of the 6 RAAT pregnant patients were all scattered in the local region, the local region was ablated accordingly, 2 patients (2/6) received extensive ablation of local areas. Immediate successful rate was similar between the two groups (6/6 vs. 93%). During follow up ((15.3±4.0) months), no complications were observed after RFA, postoperative recurrence rate was similar (1/6 vs. 12%). Uncomplicated delivery was reported in all 6 pregnant RAAT post ablation. Normal cardiac structure and function was observed in the 4 pregnant patients with tachycardia-induced cardiomyopathy post ablation. Compared to pre-ablation phase, reduced left atrial dimension ((30.3±1.3) mm vs. (36.8±6.7) mm, P>0.05), increased left ventricular ejection fraction ((64.0±2.9)% vs. (39.8±10.7)%), reduced left ventricular end-diastolic dimension ((44.8±4.0) mm vs. (60.0±2.9) mm) and reduced N-terminal B-type natriuretic peptide value ((136.2±47.5) ng/L vs. (3 408.4±901.3) ng/L) were observed at 6 months post ablation (P<0.05). Conclusion: The electrophysiological characteristics are suggestive for focal AT originating from RAA during pregnancy. Under the guidance of 3-dimension activation mapping, no fluoroscopic RFA with irrigated-tip catheter is a safe and effective strategy for the treatment of focal RAAT during pregnancy.目的： 探讨妊娠期起源于右心耳的局灶性房性心动过速（房速）患者的电生理特点和冷盐水灌注导管零射线射频消融治疗效果。 方法： 该研究为回顾性研究。选取2016年10月至2019年3月于郑州大学第一附属医院行射频消融治疗的妊娠期和非妊娠期局灶性房速女性患者55例，因例数过少排除2例非妊娠期的右心耳房速和4例妊娠期的非右心耳房速患者后，其余49例中，妊娠期右心耳房速组患者6例（12%），其中4例（4/6）为轻重程度不同的心动过速心肌病；非妊娠期且非右心耳起源的房速患者43例（88%）为对照组。收集2组患者的基线临床资料，在三维系统指导下明确局灶性房速并标出最早激动部位，妊娠期右心耳房速患者行冷盐水灌注导管的零射线射频消融，对照组患者则均在非零射线下手术。术后3、6、12个月和以后每年在门诊进行评估，检查体表心电图或动态心电图，并记录房速有无复发、有无手术并发症。妊娠期患者术后6个月进行心脏彩色多普勒超声检查和实验室检查（N末端B型脑钠肽原），并记录分娩情况。分析妊娠期右心耳房速的电生理特点，比较2组患者射频消融的疗效。 结果： 妊娠期右心耳房速组患者年龄［（30.7±6.2）岁比（57.2±11.7）岁］、左心室射血分数［（46.0±12.8）%比（60.1±5.9）%］和器质性心脏病患者比例（0比58%）低于对照组，持续性发作（6/6比7%）、胸闷和心慌症状（6/6比49%）、左心室射血分数≤50%（4/6比9%）患者比例高于对照组（P均<0.05），2组患者心率差异无统计学意义［（163.7±11.1）次/min比（153.7±15.2）次/min，P>0.05］。妊娠期右心耳房速患者有独特的体表心电图特征，P波在Ⅱ、Ⅲ、aVF导联均为直立波，Ⅰ导联P波为等电位线（1例，1/6）或直立波（5例，5/6），aVL导联P波均为等电位线（1例，1/6）或直立波（5例，5/6），V1导联P波为宽深的全负向波（5例，5/6）或正负双向波（1例，5/6），V2~V6的P波均渐转变为直立；心动周期为（361.7±38.5）ms；成功消融靶点局部A波较体表心电图P波领先（59.4±11.6）ms；三维标测显示6例患者起源点均是多点散在的片状区域，进行片状区域消融，其中2例（2/6）妊娠期患者进行了局部区域广泛消融。随访（15.3±4.0）个月，2组消融手术即刻成功率（6/6比93%）、术后复发率（1/6比12%），差异无统计学意义（P均>0.05），术后均无并发症，妊娠期右心耳房速组患者均正常分娩。4例心动过速心肌病的患者心脏结构和心功能恢复正常，与术前相比，术后6个月左心房内径减小［（30.3±1.3）mm比（36.8±6.7）mm］，但差异无统计学意义（P>0.05）；左心室射血分数升高［（64.0±2.9）%比（39.8±10.7）%］、左心室舒张末期内径减小［（44.8±4.0）mm比（60.0±2.9）mm］，N末端B型利钠肽原［（136.2±47.5）ng/L比（3 408.4±901.3）ng/L］降低（P均<0.05）。 结论： 妊娠期右心耳局灶性房速有独特的电生理表现，在三维标测下行冷盐水灌注导管零射线射频消融安全、有效。.