Bonakdar Hamid Reza, Aslanpour Masoumeh, Moladoust Hassan, Sadeghipour Parham, Mohamadi Fereshteh, Rad Mohammad Assadian, Kheirkhah Jalal
Heshmat Cardiovascular Medical Center, Guilan University of Medical Sciences, Rasht, Iran.
Cardiovascular Research Center, Guilan University of Medical Sciences, Rasht, Iran.
J Tehran Heart Cent. 2014;9(4):166-73. Epub 2014 Jul 6.
QT interval parameters have been suggested as a predictor of lethal arrhythmia and mortality in patients with myocardial infarction. The aim of the present study was to compare the value of QT interval indices in patients presenting with non-ST-segment elevation myocardial infarction (NSTEMI) between a group of patients with type 2 diabetes mellitus and a nondiabetic group of patients.
This case-control study evaluated QT interval parameters in 115 patients (47 diabetic and 68 nondiabetic patients) diagnosed with NSTEMI between September 2011 and July 2012. The following QT interval indices were analyzed: maximum (max) and minimum (min) QT interval; max and min corrected QT interval (QTc); QT dispersion (QTd); and corrected QT dispersion (QTcd). All the patients were observed for ventricular arrhythmia during their hospital course and underwent coronary angiography. They were selected to undergo coronary artery bypass surgery (CABG) or percutaneous coronary angioplasty (PCI) based on their coronary anatomy.
The mean age of the patients was 60.8 ± 11.4 years. The patients were 40.0% female and 60.0% male. There were no significant differences in clinical characters between type 2 diabetic and nondiabetic patients with NSTEMI. Compared with post-myocardial infarction patients without diabetes, those with type 2 diabetes had higher QTc max, QTd and QTcd (p value < 0.05). There was a significant difference in QTd and QTcd in the patients needing coronary revascularization with diabetes as opposed to the nondiabetics (p value = 0.035 and p value = 0.025, respectively) as well as those who had ventricular arrhythmia with diabetes (p value = 0.018 and p value = 0.003, respectively). QTcd was higher in the patients who had higher in-hospital mortality (p value = 0.047). The QTc max, QTd and QTcd were significantly (all p values < 0.05) associated with ventricular arrhythmia, QTcd with need for revascularization and QTc max with in-hospital mortality in the diabetic patients.
Based on the findings of this study, it seems that type 2 diabetics with NSTEMI have greater QTc max, QTd, and QTcd and these QT parameters may have a relationship with worse cardiac outcomes and poorer prognoses.
QT间期参数已被认为是心肌梗死患者致死性心律失常和死亡率的预测指标。本研究的目的是比较2型糖尿病患者组和非糖尿病患者组中，非ST段抬高型心肌梗死（NSTEMI）患者的QT间期指标值。
这项病例对照研究评估了2011年9月至2012年7月期间诊断为NSTEMI的115例患者（47例糖尿病患者和68例非糖尿病患者）的QT间期参数。分析了以下QT间期指标：最大（max）和最小（min）QT间期；最大和最小校正QT间期（QTc）；QT离散度（QTd）；以及校正QT离散度（QTcd）。所有患者在住院期间均观察有无室性心律失常，并接受冠状动脉造影。根据冠状动脉解剖结构，他们被选择接受冠状动脉旁路移植术（CABG）或经皮冠状动脉介入治疗（PCI）。
患者的平均年龄为60.8±11.4岁。患者中女性占40.0%，男性占60.0%。2型糖尿病NSTEMI患者和非糖尿病NSTEMI患者的临床特征无显著差异。与无糖尿病的心肌梗死后患者相比，2型糖尿病患者的QTc max、QTd和QTcd更高（p值<0.05）。需要冠状动脉血运重建的糖尿病患者与非糖尿病患者相比，QTd和QTcd存在显著差异（p值分别为0.035和0.025），有室性心律失常的糖尿病患者与非糖尿病患者相比也是如此（p值分别为0.018和0.003）。住院死亡率较高的患者QTcd更高（p值=0.047）。在糖尿病患者中，QTc max、QTd和QTcd与室性心律失常显著相关（所有p值<0.05），QTcd与血运重建需求相关，QTc max与住院死亡率相关。
基于本研究的结果，似乎NSTEMI的2型糖尿病患者具有更高的QTc max、QTd和QTcd，并且这些QT参数可能与更差的心脏结局和更差的预后有关。
