Berul C I, Hill S L, Geggel R L, Hijazi Z M, Marx G R, Rhodes J, Walsh K A, Fulton D R
Division of Pediatric Cardiology, Boston Floating Hospital for Children-New England Medical Center, Tufts University School of Medicine, Massachusetts 02115, USA.
J Cardiovasc Electrophysiol. 1997 Dec;8(12):1349-56. doi: 10.1111/j.1540-8167.1997.tb01031.x.
Following surgery for tetralogy of Fallot (TOF), children may develop late onset ventricular arrhythmias. Many patients have both depolarization and repolarization abnormalities, including right bundle branch block (RBBB) and QT prolongation. The goal of this study was to improve prospective risk-assessment screening for late onset sudden death. Resting ECG markers including QRS duration, QTc, JTc, and interlead QT and JT dispersion were statistically analyzed to identify those patients at risk for ventricular arrhythmias and sudden cardiac death. To determine predictive markers for future development of arrhythmia, we examined 101 resting ECGs in patients (age 12 +/- 6 years) with postoperative TOF and RBBB, 14 of whom developed late ventricular tachycardia (VT) or sudden death. These ECGs were also compared with an additional control group of 1000 age- and gender-matched normal ECGs. The mean QRS (+/- SD) in the VT group was 0.18 +/- 0.02 seconds versus 0.14 +/- 0.02 seconds in the non-VT group (P < 0.01). QTc and JTc in the VT group was 0.53 +/- 0.05 seconds and 0.33 +/- 0.03 seconds compared with 0.50 +/- 0.03 seconds and 0.32 +/- 0.03 seconds in the non-VT group (P = NS). There was no increase in QT dispersion among TOF patients with VT or sudden death compared with control patients or TOF patients without VT, although JT dispersion was more common in the TOF groups. A prolonged QRS duration in postoperative TOF with RBBB is more predictive than QTc, JTc, or dispersion indexes for identifying vulnerability to ventricular arrhythmias in this population, while retaining high specificity. The combination of both QRS prolongation and increased JT dispersion had very good positive and negative predictive values. These results suggest that arrhythmogenesis in children following TOF surgery might involve depolarization in addition to repolarization abnormalities. Prospective identification of high-risk children may be accomplished using these ECG criteria.
法洛四联症（TOF）手术后，儿童可能会出现迟发性室性心律失常。许多患者同时存在去极化和复极化异常，包括右束支传导阻滞（RBBB）和QT间期延长。本研究的目的是改进对迟发性猝死的前瞻性风险评估筛查。对包括QRS时限、QTc、JTc以及导联间QT和JT离散度在内的静息心电图标志物进行统计分析，以识别那些有室性心律失常和心源性猝死风险的患者。为了确定心律失常未来发生的预测标志物，我们检查了101例术后TOF且伴有RBBB的患者（年龄12±6岁）的静息心电图，其中14例发生了迟发性室性心动过速（VT）或猝死。这些心电图还与另外1000例年龄和性别匹配的正常心电图组成的对照组进行了比较。VT组的平均QRS（±标准差）为0.18±0.02秒，而非VT组为0.14±0.02秒（P<0.01）。VT组的QTc和JTc分别为0.53±0.05秒和0.33±0.03秒，非VT组分别为0.50±0.03秒和0.32±0.03秒（P=无统计学意义）。与对照组患者或无VT的TOF患者相比，伴有VT或猝死的TOF患者的QT离散度没有增加，尽管JT离散度在TOF组中更常见。在该人群中，术后TOF伴RBBB时QRS时限延长比QTc、JTc或离散度指数更能预测室性心律失常的易感性，同时保持高特异性。QRS延长和JT离散度增加的联合具有非常好的阳性和阴性预测价值。这些结果表明，TOF手术后儿童的心律失常发生可能除了复极化异常外还涉及去极化。使用这些心电图标准可能实现对高危儿童的前瞻性识别。
