Pfammatter J P, Paul T, Ziemer G, Kallfelz H C
Department of Pediatric Cardiology, Children's Hospital, Hannover, Germany.
Ann Thorac Surg. 1995 Sep;60(3):556-60. doi: 10.1016/0003-4975(95)00425-K.
Junctional ectopic tachycardia is an early postoperative complication after intracardiac repair of congenital heart disease, especially in infants. Because of the high ventricular rate and the usually poor response to antiarrhythmic drugs, this condition is associated with a high morbidity and mortality. The purpose of this study was to assess the safety and efficacy of moderate body surface hypothermia in the treatment of postoperative junctional ectopic tachycardia in infants.
Six consecutive infants with postoperative junctional ectopic tachycardia (mean age at operation, 14 weeks) were treated with surface cooling. The decision to start treatment was based on the definition of a critical heart rate (180 to 200 beats/min) in the presence of junctional ectopic tachycardia diagnosed according to established criteria. Moderate hypothermia (rectal temperature between 32 degrees and 34 degrees C) was achieved by placing ice bags on the child's body surface. The patients were sedated, mechanically ventilated, and paralyzed.
Mean interval between diagnosis of tachycardia and initiation of hypothermia was 4 hours. Rectal temperature was rapidly (within 1 hour) lowered to 32 degrees to 34 degrees C in all 6 patients. This significantly lowered the tachycardia rate from 219 +/- 27 beats/min to 165 +/- 25 beats/min (mean +/- standard deviation; p < 0.001). Three patients with signs of low cardiac output had restoration of stable hemodynamics once the tachycardia rate had been decreased by hypothermia. Cooling was maintained for a period of 24 to 88 hours (mean, 59 hours). No serious side effects were observed.
Early institution of moderate hypothermia by body surface cooling was a safe and efficient measure to control ventricular rate in infants with postoperative junctional ectopic tachycardia.
交界性异位性心动过速是先天性心脏病心内修复术后的一种早期并发症，尤其在婴儿中多见。由于心室率高且对抗心律失常药物通常反应不佳，这种情况与高发病率和死亡率相关。本研究的目的是评估中度体表低温治疗婴儿术后交界性异位性心动过速的安全性和有效性。
连续6例术后发生交界性异位性心动过速的婴儿（手术时平均年龄为14周）接受体表降温治疗。开始治疗的决定基于根据既定标准诊断为交界性异位性心动过速时的临界心率（180至200次/分钟）定义。通过在患儿体表放置冰袋实现中度低温（直肠温度在32摄氏度至34摄氏度之间）。患者接受镇静、机械通气并使用肌肉松弛剂。
心动过速诊断与低温治疗开始之间的平均间隔为4小时。所有6例患者的直肠温度均在1小时内迅速降至32摄氏度至34摄氏度。这使心动过速率从219±27次/分钟显著降至165±25次/分钟（平均值±标准差；p<0.001）。3例有低心输出量体征的患者，一旦心动过速率因低温而降低，其血流动力学恢复稳定。降温持续24至88小时（平均59小时）。未观察到严重副作用。
通过体表降温早期实施中度低温是控制婴儿术后交界性异位性心动过速心室率的一种安全有效的措施。
