ObjectiveTo explore the dynamic changes of electrocardiography (ECG) in patients with coronary heart disease(CHD) after the percutaneous coronary intervention(PCI). MethodsTo compare and analyze the regularity of the changes of 12-lead ECG on 38 cases in times,including one week,three weeks,one month,two and three months after the PCI. ResultsCompared with the ECG before the operation, the occurrences of the low-lying or the bidirectional T-wave were significantly increased,and lasting to 2 ～ 3 weeks after tie operation(5.0％ and 9.6％va2.6％ ,P ＜ 0.05). The ST segment depression( ＞ 1.0mm) and inverted T-wave in the 3 weeks and 2 months after the operation were significantly increased(5.0％ ,5.7％ vs 2.6％ ,P ＜ 0.05 ; 18.0％ and 25.2％ vs 16.2％ ,P ＜0.01 ). After that,the cases of ST segment depression were reduced to the level before PCI,and there was a significant reduction in the cases of the inverted T-wave ( P ＜ 0.01 ). ConclusionsIn the ECG of the patients with CHD after PCI, there were always early one-off abnormal Q-wave, changes of T-wave (inverted or low-lying, bidirectional)and ST segment depressions,etc. After that ,the changes above would turn back to the level before the operation.