The Short-term Change And The Clinical Implication Of Correct QT Dispersion After Stenting In Patients With Coronary Artery Disease

Objectives：Through analyzing the early changes of QTcd on coronary heart disease patientsafter PCI，we not only discuss the relationship between QTcd and the quantity ofcoronary artery lesion blood vessel and the degree of coronary artery stenosis,but alsoevaluated the earliest effect of PCI on QTcd.Methods：We selected consecutively241subjects hospitalized in the secondcardiovascular internal medicine department of Jiangxi Peopl,s Hospital from the June2013to the December2013.122patients who were treated by PCI were selected asthe research group and another119patients with luminal narrowing less than50%were selected as the control group.According to the quantity of narrow vessels,theresearch group divided into single vessel group（52cases）、double vessels group（37cases） and three vessels group（33cases）. The control group divided into normalgroup (87cases) without no stenosis and coronary artery atherosclerosis group (32cases).The ECG data were collected from all patients before they undergoing coronaryarteriography (CAG). And QTd、QTcd were measured on the first day and the thirdday after successful PCI.Measurement datum were expressed with mean士standard deviation,t-tests wereused to compare the number of two samples.The relationship between them wastested with SPSS21.0software.P<0.05was considered to be statistic significance.Results:①The QTd、QTcd of research group was higher than control group(P＜0.001).②The QTd、QTcd of research group was higher than either normal group orcoronary artery atherosclerosis group（P＜0.001）.Comparing with normal group,TheQTd、QTcd of coronary artery atherosclerosis group is higher.But differencebetween two little groups has no statistically significant(P＞0.05). ③Comparing QTcd of single vessel group、double vessels group and threevessels group,we discovered that there is no statistically significant.④According to the change of QTcd which measured on the first day afterPCI,the research group appeared two tends: rising tend and declining tend.In thedeclining group(68cases),QTcd between pre-operation and the first day afterPCI,there is a statistically significant difference.It showed a sustained downward tendon the third day after PCI although the difference is not obvious.In anothergroup,QTcd rose up on the first day and went down on the third day after PCI.Bothchanges from pre-operation to first day and from the first day to the third day weresignificant.QTcd measured on the third day after PCI is still higher than measuredpre-operation.Comparing QTcd of declining group with QTcd of rising group,wefound that the former is higher than the latter before PCI.Conclusions:①Coronary arterial stenosis can increase the QTcd.②QTcd closely relate to the degree of coronary artery stenosis； QTcd hasnothing to do with the quantity of narrow coronary artery.③In the long term,PCI can reduce the QTcd and increase the electrical stabilityof myocardial cells. But,the short-term effect of PCI on QTcd in different CADpatients is different.Because of the operate injury, PCI can damage the electricalstability of myocardial cells for transient.But,it can came back to the baseline in ashort while and decrease in3days.