Janousek J, Paul T, Bartáková H
Center of Pediatric Cardiology and Cardiac Surgery, University Hospital Motol, Prague, Czech Republic.
Am J Cardiol. 1995 Jan 15;75(2):146-50. doi: 10.1016/s0002-9149(00)80064-8.
This study evaluates the role of late potentials in identifying patients with sustained ventricular tachycardia (VT) after surgery for congenital heart defects using right ventriculotomy. Nine patients with early (1 to 12 months) or late VT (spontaneous in 7 [induced during electrophysiologic study in 6 of the 7] and induced in 2) and 104 patients without VT were studied. All patients had complete right bundle branch block. Late potentials were quantified by 3 time-domain parameters of the signal-averaged electrocardiogram: total filtered QRS duration, root-mean-square voltage in the last 40 ms, and low-amplitude signal duration of the terminal filtered QRS complex. Root-mean-square voltage filtered at 80 to 250 Hz was lower in patients with than without VT (9 +/- 6 vs 16 +/- 8 microV, p < 0.01). By multivariate analysis, more complex surgery (i.e., insertion of extracardiac conduits, Kawashima operation, etc.), lower root-mean-square voltage, and higher Lown grade (2 to 5) of ventricular arrhythmias on routine postoperative Holter recordings were the only independent predictors of VT (p < 0.001, < 0.05, and < 0.05, respectively). A combination of more complex surgery, root-mean-square voltage < 14 microV, and Lown grade 2 to 5 ventricular arrhythmias was highly predictive of VT (positive predictive value 75%). Conversely, patients without complex surgery and with root-mean-square voltage of > 13 microV were not likely to develop VT (negative predictive value 100%). Late potentials are an independent predictor of VT and may improve the identification of patients at low and high risk of VT after surgery for congenital heart defects using right ventriculotomy.
本研究评估了晚电位在识别先天性心脏缺陷右心室切开术后发生持续性室性心动过速（VT）患者中的作用。对9例早期（1至12个月）或晚期VT患者（7例为自发性[7例中的6例在电生理研究中诱发]，2例为诱发性）和104例无VT患者进行了研究。所有患者均有完全性右束支传导阻滞。通过信号平均心电图的3个时域参数对晚电位进行量化：总滤波QRS时限、最后40毫秒的均方根电压以及终末滤波QRS波群的低振幅信号持续时间。与无VT患者相比，VT患者在80至250赫兹滤波后的均方根电压更低（9±6微伏对16±8微伏，p<0.01）。多因素分析显示，更复杂的手术（即心外管道置入、川岛手术等）、更低的均方根电压以及术后常规动态心电图记录中更高的室性心律失常Lown分级（2至5级）是VT的唯一独立预测因素（分别为p<0.001、<0.05和<0.05）。更复杂的手术、均方根电压<14微伏以及Lown分级2至5级室性心律失常同时存在对VT具有高度预测性（阳性预测值75%）。相反，无复杂手术且均方根电压>13微伏的患者不太可能发生VT（阴性预测值100%）。晚电位是VT的独立预测因素，可能有助于改善对先天性心脏缺陷右心室切开术后VT低风险和高风险患者的识别。
