[Association of QT dispersion, ST/heart rate slope and ST-segment depression in exercise test to evaluate restenosis after percutaneous coronary intervention].

OBJECTIVE: To evaluate the sensitivity and specificity of QT dispersion (QTd) and ST/heart rate slope (ST/HRs) at the end of ECG exercise test plus ST-segment depression on diagnosing restenosis after percutaneous coronary intervention (PCI). METHODS: Between November 2001 and December 2003, 129 patients underwent PCI successfully, and they were examined 3-6 months later. At the end of treadmill exercise, QTd and ST/HRs were measured. All patients also accepted coronary angiography to ascertain whether he/she had restenosis. The results of QTd and ST/HRs plus ST-segment depression were then evaluated. RESULTS: The sensitivity and specificity of QTd and ST/HRs plus ST-segment depression were 84.6% and 80.4% respectively. Both of them were significantly higher than conventional ST-segment depression standard (sensitivity was 53.3% and specificity was 66.7%, P<0.05). CONCLUSION: Measuring QTd and ST/HRs at the end of ECG treadmill exercise test plus ST-segment depression can be used for the diagnosis of restenosis after PCI.