Yilmaz Remzi, Demirbag Recep, Gur Mustafa
Department of Cardiology, Faculty of Medicine, Harran University, Sanliurfa, Turkey.
Ann Noninvasive Electrocardiol. 2006 Jan;11(1):43-51. doi: 10.1111/j.1542-474X.2006.00081.x.
Although prolongation of the QT intervals in acute ischemic conditions, such as acute myocardial infarction, intracoronary balloon inflation, and exercise induced ischemia, has been shown, association of rest QT intervals with extent and severity of stable coronary artery disease (CAD) has not been assessed so far. The effects of extent and severity of stable CAD on rest QT interval were analyzed in this study.
Rest 12-lead electrocardiograms (ECG) were recorded in 162 clinically stable subjects undergoing coronary angiography before the angiography for measurement of corrected QT dispersion (cQTd) and the QT dispersion ratio (QTdR) defined as QT dispersion divided by cycle length and expressed as a percentage. Angiographic "vessel score,""diffuse score," and "Gensini score" were used to evaluate the extent and severity of coronary atherosclerosis. Subjects were grouped as follows: those with normal angiogram (Group 1), those with insignificant (<50%) coronary stenosis (Group 2), and those with 1- (Group 3), 2- (Group 4), or 3-vessel disease (Group 5).
cQTd and QTdR were higher in Group 3 compared with Group 1 (P < 0.001 and P = 0.001, respectively), in Group 4 compared with Group 1 (P < 0.001 for both) and Group 2 (P = 0.001 and P = 0.003, respectively), and in Group 5 compared with Group 1 (P < 0.001 for both) and Group 2 (P < 0.001 and P = 0.003, respectively). cQTd and QTdR were positively correlated with the vessel score (r = 0.422, P < 0.001; r = 0.358, P < 0.001, respectively), diffuse score (r = 0.401, P < 0.001; r = 0.357, P < 0.001, respectively) and Gensini score (r = 0.378, P < 0.001; r = 0.373, P < 0.001, respectively). In multiple linear regression analyses, cQTd was found to be independently associated only with diffuse score (beta= 0.325, P = 0.038). Also, QTdR was independently associated with diffuse score (beta= 0.416, P = 0.006) and Gensini score (beta= 0.374, P = 0.011).
Rest cQTd and QTdR are increased, and related to the extent and severity of coronary atherosclerosis in patients with stable CAD.
尽管已表明在急性缺血情况下，如急性心肌梗死、冠状动脉内球囊扩张和运动诱发的缺血，QT间期会延长，但静息QT间期与稳定型冠状动脉疾病（CAD）的范围和严重程度之间的关联迄今尚未得到评估。本研究分析了稳定型CAD的范围和严重程度对静息QT间期的影响。
对162例临床稳定且接受冠状动脉造影的受试者，在造影前记录静息12导联心电图（ECG），以测量校正QT离散度（cQTd）和QT离散度比率（QTdR），QTdR定义为QT离散度除以心动周期长度并以百分比表示。采用血管造影“血管评分”“弥漫性评分”和“Gensini评分”来评估冠状动脉粥样硬化的范围和严重程度。受试者分为以下几组：血管造影正常者（第1组）、冠状动脉狭窄不显著（<50%）者（第2组）、单支血管病变者（第3组）、双支血管病变者（第4组）或三支血管病变者（第5组）。
与第1组相比，第3组的cQTd和QTdR更高（分别为P < 0.001和P = 0.001），与第1组相比，第4组的cQTd和QTdR更高（两者均为P < 0.001），与第2组相比，第4组的cQTd和QTdR更高（分别为P = 0.001和P = 0.003）；与第1组相比，第5组的cQTd和QTdR更高（两者均为P < 0.001），与第2组相比，第5组的cQTd和QTdR更高（分别为P < 0.001和P = 0.003）。cQTd和QTdR与血管评分呈正相关（分别为r = 0.422，P < 0.001；r = 0.358，P < 0.001）、与弥漫性评分呈正相关（分别为r = 0.401，P < 0.001；r = 0.357，P < 0.001）以及与Gensini评分呈正相关（分别为r = 0.378，P < 0.001；r = 0.373，P < 0.001）。在多元线性回归分析中，发现cQTd仅与弥漫性评分独立相关（β = 0.325，P = 0.038）。此外，QTdR与弥漫性评分独立相关（β = 0.416，P = 0.006）和Gensini评分独立相关（β = 0.374，P = 0.011）。
稳定型CAD患者的静息cQTd和QTdR升高，且与冠状动脉粥样硬化的范围和严重程度相关。
