RESUMO
Objective: To evaluate the efficiency of left cardiac sympathetic denervation (LCSD) in inherited arrhythmia patients with adrenergic activity-induced malignant ventricular arrhythmia, and observe exercise-stress test features before and after LCSD. Methods: This retrospective observational study included catecholaminergic polymorphic ventricular tachycardia(CPVT) and long QT syndromes(LQTS) patients who underwent video-assisted LCSD at Beijing Tsinghua Changgung Hospital and Peking University People's Hospital from September 2006 to May 2020. The indications for LCSD surgery were intolerant or refractory to beta-blocker medication. Clinical and exercise-stress tests data of included patients were collected before and 1 month after LCSD. Heart rate, exercise tolerance, atrial and ventricular arrhythmia, QTc interval and predictors for sudden cardiac death were analyzed. Patents were regularly followed up at 1, 3, 6, and 12 months after LCSD and then once every year thereafter. Cardiac events and medication adjustment records were collected. Results: Five patients (2 CPVT, 1 LQT1, and 2 LQT2)were included in the study. All patients experienced syncope as first symptom at the median age of 12(10, 16)years, and underwent LCSD at the median age of 21(16, 26)years, Baseline heart rate was similar before and after LCSD ((65.6±6.5) beats/min vs. (68.0±11.1) beats/min, P=0.57); while maximum workload tended to be lower after LCSD ((12.1±2.8) metabolic equivalents (METS) before surgery vs. (10.5±2.4) METS after surgery, P=0.07). Incidence of atrial and ventricular arrhythmia were significantly reduced post LCSD, and the ventricular arrhythmia score was decreased after LCSD in CPVT patients (4 points before LCSD vs. 3 points after LCSD in case 1;5 points before LCSD vs. 3 points after LCSD in case 2). QTc interval was shortened significantly in three LQTs patients (QTc interval at baseline heart rate: (546.6±72.3) ms before surgery vs. (493±61.1) ms after LCSD, P=0.047; QTc interval at maximal exercise heart rate: (516.3±73.7) ms before surgery vs. (486.7±64.2)ms after LCSD, P=0.035). Additionally, sudden cardiac death risk indicator ΔHRR1 (heart rate decreasing value within the first 1 min during recovery phase) decreased from (51.5±21.1) beats/min before surgery to (32.0±13.9) beats/min after surgery (P=0.035). During a median follow-up of 1(1, 4) year, all five patients were on low dosage of propranolol (37.0±21.7) mg/d. Cardiac events free survival was achieved in four out of 5 patients (80%) after sympathectomy, while 1 case suffered from sudden cardiac death after emotional stress. Conclusion: LCSD surgery can be safely and effectively performed in most hereditary arrhythmia patients with adrenergic activity-induced life-threatening cardiac events. Exercise stress test results show that LCSD could reduce malignant arrhythmias and improve sudden cardiac death risk indicators without decreasing heart rate.
RESUMO
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.