Objective: To evaluate the main triggers of recurrent cardiac events in patients with symptomatic congenital long QT syndrome (cLQTS). Methods: In this retrospective case analysis study, clinical characteristics were reviewed from 38 patients with recurrent cardiac events after first visit out of 66 symptomatic cLQTS patients. General clinical data such as gender, age, clinical presentation, family history and treatment were collected, auxiliary examination results such as electrocardiogram and gene detection were analyzed. LQTS-related cardiac events were defined as arrhythmogenic syncope, implantable cardioverter defibrillator (ICD) shock, inappropriate ICD shock, aborted cardiac arrest, sudden cardiac death or ventricular tachycardia. Results: A total of 38 patients with recurrent symptoms were enrolled in this study, including 30 females (79%) and 14 children (37%). The average age of onset was (15.6±14.6) years, and the recurrence time was (3.6±3.5) years. Subtype analysis showed that there were 11 cases (29%) of LQT1 (including 2 cases of jervel-Lange Nielson syndrome), 19 cases (50%) of LQT2, 5 cases (13%) of LQT3 and 3 cases (8%) of other rare subtypes (1 LQT5, 1 LQT7 and 1 LQT11) in this patient cohort. LQT1 patients experienced recurrent cardiac event due to drug withdrawal (6 (55%)), specific triggers (exercise and emotional excitement) (4 (36%)) and medication adjustment (1 (9%)). For LQT2 patients, main triggers for cardiac events were drug withdrawal (16 (84%)), specific triggers (shock, sound stimulation, waking up (6 (32%)). One patient (5%) had recurrent syncope after pregnancy. One patient (20%) had inappropriate ICD shock. For LQT3 patients, 4 (80%) patients developed syncope during resting state, and 1 (20%) developed ventricular tachycardia during exercise test. One LQT5 patients experienced syncope and ICD shock under specific triggers (emotional excitement). One LQT11 patient had repeated ICD shocks under specific inducement (fatigue). One LQT7 patient experienced inappropriate ICD shock. Left cardiac sympathetic denervation (LCSD) significantly alleviated the symptoms in 2 children with Jervell-Lange Nielson syndrome (JLNS) post ineffective β-blocker medication. Nadolol succeeded in eliminating cardiac events in one patient with LQT2 post ineffective metoprolol medication. Mexiletine significantly improved symptoms in 2 patients with LQT2 post ineffective β-blocker medication. Conclusions: Medication withdrawal is an important trigger of the recurrence of cardiac events among patients with symptomatic congenital long QT syndrome.
目的： 评估症状性先天性长QT综合征（congenital long QT syndrome，cLQTS）患者心脏事件复发的主要诱因。 方法： 本研究为回顾性病例分析。在2014年11月至2020年2月就诊于北京清华长庚医院的66例症状性cLQTS患者中，选取首次就诊后心脏事件复发的38例为研究对象。采集患者性别、发病和就诊年龄、就诊前后临床表现、家族史、治疗情况、心电图和cLQTS亚型资料。回顾性分析患者心脏事件发作时间、次数、诱因以及药物治疗情况和心电图资料。心脏事件包括：晕厥、埋藏式心脏转复除颤器（implantable cardioverter defibrillator，ICD）放电、ICD误放电、心脏骤停生还、心脏性猝死、心电图证实发生室性心动过速。 结果： 38例心脏事件复发的cLQTS患者中，女性30例（79%），儿童14例（37%），发病年龄（15.6±14.6）岁，就诊后复发时间为（3.6±3.5）年。亚型分析表明纳入11例（29%）LQT1（含2例Jervell-Lange-Nielson综合征患儿）、19例（50%）LQT2、5例（13%）LQT3及3例（8%）其他少见亚型（1例LQT5、1例LQT7和1例LQT11）。LQT1患者中共6例（55%）患者因停药和/或漏服药物出现心脏事件发作；4例（36%）患者在特定诱因（运动、情绪激动）下发生晕厥；1例（9%）患者自行换药后出现晕厥发作。LQT2中共16例（84%）患者因漏服和/或停药后出现心脏事件，3例（16%）患者于特定诱因（惊吓、声音刺激、睡醒）下心脏事件发作；1例（5%）患者怀孕后出现反复晕厥发作；1例（20%）患者发生ICD误放电。LQT3患者中4例（80%）患者反复静息状态下出现晕厥；1例（20%）患者于心电图运动平板试验过程中出现室性心动过速。1例LQT5患者特定诱因（情绪激动、休息时）下反复出现晕厥及ICD放电。1例LQT11患者特定诱因（劳累）下有反复ICD放电。1例LQT7患者随访过程中出现ICD误放电。随访过程中2例Jervell-Lange-Nielson综合征患儿和2例LQT2患者因β受体阻滞剂效果不佳行交感神经节切除术后晕厥发作较前减少；1例服用美托洛尔后仍有晕厥发作的LQT2患者改服纳多洛尔后无晕厥发作；2例服用β受体阻滞剂效果不佳的LQT2患者加用美西律治疗后症状较前改善。 结论： 自行停药或漏服药物是心脏事件复发的重要诱因。.