Eldar M, Griffin J C, Van Hare G F, Witherell C, Bhandari A, Benditt D, Scheinman M M
Department of Medicine, University of California, San Francisco.
J Am Coll Cardiol. 1992 Oct;20(4):830-7. doi: 10.1016/0735-1097(92)90180-u.
The objective of this study was to review our current experience using a combination of beta-adrenergic blocking agents and long-term cardiac pacing to treat patients with the idiopathic long QT syndrome.
Patients with the idiopathic long QT syndrome are at high risk for sudden cardiac death. Before combination therapy, 20 of the 21 study patients experienced either cardiac arrest (n = 8) or syncope (n = 18) and 11 had documented polymorphous ventricular tachycardia. Nine of these patients had not responded to isolated beta-blocker therapy and five had not responded to isolated left cervicothoracic sympathectomy.
All patients were treated with combined beta-blocker therapy and long-term cardiac pacing at a rate designed to normalize the QT interval.
Cardiac pacing at rates of 70 to 125 beats/min resulted in shortening of the QT and corrected QT (QTc) intervals from 517 +/- 78 and 541 +/- 62 ms to 404 +/- 37 and 479 +/- 41 ms, respectively. The mean follow-up interval after institution of pacing was 55 +/- 45 months. The only sudden death occurred in a patient who had discontinued beta-blocker therapy. Syncope occurred in four patients, two of whom had interrupted pacemaker function due to lead fracture. Pacemaker problems, partly attributable to the specific rate required for QT interval shortening and to avoidance of T wave sensing, were relatively common. No patient who continued the combination therapy died, but 10% of these patients had a recurrence of symptoms.
Combination therapy with a beta-blocker and cardiac pacing appears to be a highly effective primary therapy for symptomatic patients with the long QT syndrome and to provide excellent adjunctive therapy for patients who require insertion of an automatic internal defibrillator.
本研究的目的是回顾我们目前使用β-肾上腺素能阻滞剂和长期心脏起搏联合治疗特发性长QT综合征患者的经验。
特发性长QT综合征患者有心脏性猝死的高风险。在联合治疗前，21例研究患者中有20例经历过心脏骤停（n = 8）或晕厥（n = 18），11例有记录的多形性室性心动过速。这些患者中有9例对单独的β受体阻滞剂治疗无反应，5例对单独的左颈胸交感神经切除术无反应。
所有患者均接受β受体阻滞剂联合治疗和长期心脏起搏，起搏频率旨在使QT间期正常化。
以70至125次/分钟的频率进行心脏起搏，使QT和校正QT（QTc）间期分别从517±78和541±62毫秒缩短至404±37和479±41毫秒。起搏开始后的平均随访间隔为55±45个月。唯一的猝死发生在一名停用β受体阻滞剂治疗的患者身上。4例患者发生晕厥，其中2例因导线断裂导致起搏器功能中断。起搏器问题相对常见，部分归因于QT间期缩短所需的特定频率以及避免T波感知。继续联合治疗的患者中无一例死亡，但这些患者中有10%出现症状复发。
β受体阻滞剂和心脏起搏联合治疗似乎是有症状的长QT综合征患者的一种高效主要治疗方法，并且为需要植入自动体内除颤器的患者提供了出色的辅助治疗。
