Vandenberk Bert, Vandael Eline, Robyns Tomas, Vandenberghe Joris, Garweg Christophe, Foulon Veerle, Ector Joris, Willems Rik
Department of Cardiovascular Sciences, University of Leuven, Leuven, Belgium.
Department of Cardiology, University Hospitals Leuven, Leuven, Belgium.
Pacing Clin Electrophysiol. 2018 Sep;41(9):1101-1108. doi: 10.1111/pace.13423. Epub 2018 Jul 12.
Incorporation of QTc in clinical decision support systems requires accurate QT-interval correction, also during common electrocardiogram abnormalities as ventricular conduction defects (VCD). We compared the performance and predictive value of QT correction formulas to design a patient-specific QT correction algorithm (QTcA).
The first ECG in adult patients with sinus rhythm (SR), atrial fibrillation (AF), and ventricular pacing (VP) was collected retrospectively. QT correction was performed with Bazett (QTcB), Fridericia (QTcFri), Framingham, Hodges, and Rautaharju (QTcR) formulas. Correction formulas were compared using QTc/RR linear regression. Adjusted Cox regression was performed to predict 1-year all-cause mortality.
A total of 49,737 patients were included (70.0% SR, 24.1% AF, 5.9% VP, 11.1% VCD). Overall 1-year all-cause mortality rate was 11.8%. In patients without VCD or VP, QTcFri showed significantly better heart rate correction, both overall (P < 0.001) and in subgroups by heart rate (bradycardia P ≤ 0.001, normal P ≤ 0.050, tachycardia P ≤ 0.010). Furthermore, QTcFri improved mortality prediction significantly when compared to QTcB (P < 0.001). Patients with VCD or VP QTcR, including correction for QRS duration, had a significant better heart rate correction than QTcB (P ≤ 0.010) and improved mortality prediction significantly compared to all other formulas (P < 0.001). Implementing QTcA, designed based on QTcFri and QTcR depending on the presence of VCD or VP, reduced the patients considered to be at risk by 61.1% when compared to QTcB.
A patient-specific QT correction algorithm would combine accurate heart rate correction, improved predictive value of mortality, and a reduction of patients considered to be at risk.
在临床决策支持系统中纳入QTc需要准确的QT间期校正，在常见心电图异常如心室传导缺陷（VCD）时也如此。我们比较了QT校正公式的性能和预测价值，以设计一种针对患者的QT校正算法（QTcA）。
回顾性收集成年窦性心律（SR）、心房颤动（AF）和心室起搏（VP）患者的首份心电图。使用Bazett（QTcB）、Fridericia（QTcFri）、弗雷明汉、霍奇斯和劳塔哈尔尤（QTcR）公式进行QT校正。使用QTc/RR线性回归比较校正公式。进行校正后的Cox回归以预测1年全因死亡率。
共纳入49737例患者（70.0%为SR，24.1%为AF，5.9%为VP，11.1%有VCD）。总体1年全因死亡率为11.8%。在无VCD或VP的患者中，QTcFri在总体上（P<0.001）以及按心率分组的亚组中（心动过缓P≤0.001，正常P≤0.050，心动过速P≤0.010）显示出显著更好的心率校正效果。此外，与QTcB相比，QTcFri显著改善了死亡率预测（P<0.001）。有VCD或VP的患者，QTcR（包括对QRS时限的校正）的心率校正效果显著优于QTcB（P≤0.010），与所有其他公式相比，显著改善了死亡率预测（P<0.001）。实施基于QTcFri和QTcR（取决于是否存在VCD或VP）设计的QTcA，与QTcB相比，被认为有风险的患者减少了61.1%。
针对患者的QT校正算法将结合准确的心率校正、改善的死亡率预测价值以及减少被认为有风险的患者数量。
