Wang J N, Wu J M, Tsai Y C, Lin C S
Department of Pediatrics, National Cheng Kung University Hospital, Tainan, Taiwan.
J Formos Med Assoc. 2000 Oct;99(10):766-70.
Ectopic atrial tachycardia (EAT) is an unusual and potentially risky arrhythmia that can result in left ventricular dysfunction if not properly managed. In adults, EAT is mainly caused by diseased atrial myocardium and responds poorly to antiarrhythmic drugs. The characteristics of EAT in children might be different from those in adults because of their immature myocardium and the different electrophysiologic characteristics of their conduction tissue. We examined the natural history and treatment of EAT in children.
From June 1990 through June 1999, 24 children (8 girls and 16 boys; median age 4 mo [1 d-10 yr]) were admitted to our hospital with a diagnosis of EAT. Fifteen had healthy hearts, six had congenital heart disease, one had myocarditis, one had bronchopulmonary dysplasia with severe pulmonary hypertension, and one had hypertrophic cardiomyopathy. Thirteen patients presented with congestive heart failure. Only four patients had symptoms of prodromal airway infection. The maximum atrial rate was 244 +/- 66 beats per minute. Atrioventricular block was documented at least once during tachycardia in 10 patients. Warm-up or cool-down phenomenon was seen at the initiation or termination of tachycardia in thirteen patients. Primary pharmacologic treatment was attempted in all patients. EAT was initially controlled in all patients using digoxin plus propranolol (18 patients), propranolol only (4), or digoxin plus procainamide (2). EAT was controlled using medication in 22 patients. Fifteen patients had sinus rhythm but did not receive medication for 39 +/- 25 months. Two patients died of uncontrolled arrhythmia, and two of underlying disease. Recurrence was seen within 3 months after initial therapy in five patients. Surgery was performed to correct the underlying heart disease in three patients with frequently recurring EAT, all of whom remained tachycardia-free after surgery, without pharmacologic treatment. The spontaneous remission rate was 75% (18/24).
EAT in children without underlying heart disease can be effectively treated using antiarrhythmic drugs. Spontaneous resolution of EAT after medication in children was frequent (75%) in this series. The results of this study suggest that a step-wise approach using digoxin, a beta-blocker, and a class I antiarrhythmic drug may be the most effective treatment for EAT.
异位房性心动过速（EAT）是一种不常见且有潜在风险的心律失常，如果处理不当可导致左心室功能障碍。在成人中，EAT主要由患病的心房心肌引起，对抗心律失常药物反应不佳。由于儿童心肌不成熟以及其传导组织电生理特性不同，儿童EAT的特征可能与成人不同。我们研究了儿童EAT的自然病程及治疗方法。
1990年6月至1999年6月，24例儿童（8例女孩，16例男孩；中位年龄4个月[1天至10岁]）因EAT诊断入院。15例心脏健康，6例有先天性心脏病，1例有心肌炎，1例有支气管肺发育不良伴严重肺动脉高压，1例有肥厚型心肌病。13例患者出现充血性心力衰竭。只有4例患者有前驱呼吸道感染症状。最大心房率为244±66次/分钟。10例患者在心动过速期间至少记录到一次房室传导阻滞。13例患者在心动过速开始或终止时出现热身或冷却现象。所有患者均尝试进行初始药物治疗。所有患者最初使用地高辛加普萘洛尔（18例）、仅使用普萘洛尔（4例）或地高辛加普鲁卡因胺（2例）控制EAT。22例患者通过药物控制了EAT。15例患者恢复窦性心律，且39±25个月未用药。2例患者死于心律失常未控制，2例死于基础疾病。5例患者在初始治疗后3个月内复发。3例EAT频繁复发的患者接受手术纠正基础心脏病，术后均未出现心动过速，无需药物治疗。自发缓解率为75%（18/24）。
无基础心脏病的儿童EAT可使用抗心律失常药物有效治疗。本系列研究中儿童EAT药物治疗后频繁出现自发缓解（75%）。本研究结果表明，使用地高辛、β受体阻滞剂和I类抗心律失常药物的逐步治疗方法可能是治疗EAT最有效的方法。
