Demirtaş Abdullah Orhan, Urgun Orsan Deniz
Cardiology Department, Adana Health Practice and Research Center, Health Science University, Adana, Turkey.
Arch Med Sci Atheroscler Dis. 2019 Mar 4;4:e7-e12. doi: 10.5114/amsad.2019.83299. eCollection 2019.
Exercise electrocardiography (EET) is frequently used in coronary artery disease, but the specificity of this test is very low. In the literature, parameters such as QT prolongation and QT dispersion which show coronary artery disease and arrhythmia were not sufficiently investigated using EET. The aim of this study was to investigate whether QT interval prolongation or dispersion (QT disp) in a positive EET test could predict critical coronary artery disease (CAD).
Patients with a positive exercise test were included in the study. Data regarding QT, QTc (corrected QT interval) and QT disp values before, during and after EET were noted. Critical coronary artery occlusions (≥ 70%) was recorded from coronary angiographic images. Patients were divided into two groups (critical CAD and non-critical CAD).
A total of 192 patients were found to be eligible for the study. There were 126 patients in the non-critical CAD group (group 1) and 66 patients in the critical CAD group (group 2). Recovery QTc, peak QT disp, and recovery QT disp were significantly increased in group 2 ( < 0.001 for each). Also, target heart rate ( = 0.012), basal systolic blood pressure ( = 0.005) and diastolic blood pressure ( < 0.001) were significantly higher in group 1. Recovery QTc (OR = 1.051) and recovery QT disp (OR = 1.117) were determined as the independent predictors for critical CAD. The ROC analysis results indicated that critical CAD could be diagnosed with 90% sensitivity when the recovery QTc cut-off value was set as 404 ms.
In patients with positive EET, prolonged QTc and QT disp values measured during the recovery period would predict critical CAD. Thus, the clinical accuracy of EET may be enhanced.
运动心电图（EET）常用于冠状动脉疾病，但该检查的特异性很低。在文献中，诸如QT间期延长和QT离散度等显示冠状动脉疾病和心律失常的参数，尚未通过EET进行充分研究。本研究的目的是探讨EET试验阳性时QT间期延长或离散度（QT disp）是否可预测严重冠状动脉疾病（CAD）。
本研究纳入运动试验阳性的患者。记录EET前、中、后有关QT、QTc（校正QT间期）和QT disp值的数据。从冠状动脉造影图像记录严重冠状动脉闭塞（≥70%）情况。患者分为两组（严重CAD组和非严重CAD组）。
共发现192例患者符合研究条件。非严重CAD组（第1组）有126例患者，严重CAD组（第2组）有66例患者。第2组的恢复QTc、峰值QT disp和恢复QT disp显著增加（每项均<0.001）。此外，第1组的目标心率（=0.012）、基础收缩压（=0.005）和舒张压（<0.001）显著更高。恢复QTc（OR = 1.051）和恢复QT disp（OR = 1.117）被确定为严重CAD的独立预测因素。ROC分析结果表明，当恢复QTc临界值设定为404 ms时，诊断严重CAD的敏感性可达90%。
在EET试验阳性的患者中，恢复期测量的QTc和QT disp值延长可预测严重CAD。因此，可提高EET的临床准确性。
