Bissinger Andrzej, Markuszewski Leszek, Rosiak Marcin
Uniwersytet Medyczny w łodzi, Klinika Kardiologii Interwencyjnej, Kardiodiabetologii i Rehabilitacji Kardiologicznej, I Katedra Kardiologii i Kardiochirurgii.
Pol Merkur Lekarski. 2008 Feb;24(140):90-4.
The frequency of onset of acute coronary syndromes and sudden cardiac death has been reported to have circadian variations, with a peak incidence in early morning hours. It has also been known that acute ischemia is a potent stimulus to increased dispersion of repolarization and development of malignant arrhythmias. QT dispersion (QTd) is used as an index of heterogenity of the ventricular repolarization and increases in patients with ischemic heart disease. The aim of the study was to investigate diurnal variations of QTd in patient with triple-vessel coronary artery disease (CAD) with and without diabetes mellitus type 2 (DM).
We investigated of 28 patients with stable triple-vessel CAD and 32 patients with similar advancement of changes in coronary circulation with co-existing DM. We excluded patients with prior myocardial infarction, taking oral medications which might alter QT interval and patients in which measurements of QT were difficult to perform or impossible. QTd measurements were taken semi-automatically every hour from 24 hours 12 leads Holter monitoring system (SUPRIMA 12). Measurements were verified independently by three observers.
CAD patients without DM had QTd significantly greater in the morning hours (6 a.m. to 9 a.m.) in comparison with the other times (p < 0.01). The shortest QTd was measured during the night between 10 p.m. and 1 a.m. We did not observed circadian variations of QTd in patients with co-existent DM and values of QTd in this group was significantly greater then in CAD without DM group (p < 0.001).
Our data proved that QTd in patients with CAD had a circadian variation with a peak value in the morning hours shortly after awakening. Patients with DM and CAD had not circadian variation of QTd but QTd values, during whole day and night, were significantly greater then patients without DM.
据报道，急性冠脉综合征和心源性猝死的发病频率存在昼夜变化，清晨时段发病率最高。还已知急性缺血是导致复极离散增加和恶性心律失常发生的有力刺激因素。QT离散度（QTd）用作心室复极异质性的指标，在缺血性心脏病患者中会增加。本研究的目的是调查伴有和不伴有2型糖尿病（DM）的三支血管冠状动脉疾病（CAD）患者QTd的昼夜变化。
我们调查了28例稳定型三支血管CAD患者和32例伴有DM且冠状动脉循环变化程度相似的患者。我们排除了既往有心肌梗死、服用可能改变QT间期的口服药物的患者，以及难以或无法进行QT测量的患者。通过24小时12导联动态心电图监测系统（SUPRIMA 12）每小时半自动测量一次QTd。测量结果由三名观察者独立核实。
无DM的CAD患者清晨时段（上午6点至9点）的QTd明显大于其他时段（p<0.01）。最短的QTd在晚上10点至凌晨1点之间测得。我们未观察到伴有DM的患者QTd的昼夜变化，且该组的QTd值明显高于无DM的CAD组（p<0.001）。
我们的数据证明，CAD患者的QTd存在昼夜变化，觉醒后不久的清晨时段达到峰值。伴有DM和CAD的患者不存在QTd的昼夜变化，但全天和夜间的QTd值明显高于无DM的患者。
