目的：观察经皮冠状动脉腔内成形术(PTCA)对QT间期离散度(QTd)的影响及PTCA术后再狭窄时QTd的变化。探讨QTd在预测再狭窄中的意义。

方法：将30例临床拟诊PTCA术后再狭窄的患者根据第2次冠状动脉造影(冠造)的结果分为再狭窄组(19例)及非再狭窄组(11例)。对两组患者第1次PTCA术前后、第2次PTCA(或冠造)术前后的标准12导联心电图进行QTd(QTd=最大QT间期-最小QT间期)及校正的QT离散度(QTcd)的测定。

结果：两组患者第1次PTCA术后QTd及QTcd均较术前显著减少(P＜0.0005)。再狭窄组第2次PTCA术前QTcd(70.9±17.1 ms)又恢复至第1次PTCA术前(73.5±17.2 ms)的水平，且显著大于(P＜0.000 1)第1次PTCA术后(35.2±8.9 ms)及第2次PTCA术后(34.5±9.3 ms)的水平。非再狭窄组第2次冠造前QTcd(30.7±8.5 ms)与第1次PTCA术后(29.3±8.1 ms)比较无显著变化(P＞0.05),仍显著小于(P＜0.000 5)第1次PTCA术前(69.6±12.7 ms)。

结论：PTCA术可降低冠心病患者QT离散度，再狭窄时QT离散度再度增高。QT离散度可作为预测PTCA术后再狭窄的一项指标。

Effects of Percutaneous Transluminal Coronary Angioplasty and Restenosis

on QT Dispersion in Patients with Coronary Heart Disease (Abstract)

Division of Coronary heart Disease, Cardiovascular Institute and Fu Wai Hospital, CAMS and PUMC, beijing (100037)

liu Haibo, Liu Xiaohui, Gao Runlin, et al.

objective: To measure the changes of QT dispersion after successful percutaneous transluminal coronary angioplasty (PTCA) and in the situation of restenosis, and determine the predictive value of QT dispersion in restenosis after PTCA.

Methods: thirty patients with symptomatic restenosis underwent repeat coronary angiography, and divided into two groups (angiographically confirmed): restenosis group (19) and non-restenosis group (11). Standard 12-lead electrocardiograms were performed 24 hours before the first PTCA, one hour and 6 days after the first PTCA, 24 hours before and 1 hour after the second PTCA or coronary angiography. QT dispersion was calculated as the differences in the maximum and minimum corrected QT intervals.

Results: corrected QT dispersion (QTcd) after the first PTCA was significantly decreased compared with that before the first PTCA (p＜0.000 5) in both groups. In restenosis group, QTcd before the second PTCA increased again (70.9±17.1 ms vs.35.2±8.9 ms after the first PTCA, p＜0.000 1), QTcd after the second PTCA was significantly reduced again (34.5±9.3 ms vs. before the second PTCA and 73.5±17.2 ms before the first PTCA, p＜0.000 1). In non-restenosis group, QTcd before and after the second coronary angiography was not significantly (p＞0.05) changed compared with that after the first PTCA, and still lower (p＜0.000 5) than that before the first PTCA (30.7±8.5 ms, 33.4±8.3 ms, 29.3±8.1 ms and69.6±12.7 ms, respectively).

Conclusion: qT dispersion decrease after successful PTCA and increases again with restenosis. qT dispersion may be a valuable marker of restenosis after PTCA.