冠状动脉内心电图对冠状动脉腔内球囊扩张时缺血预适应的评价

通过对15例经皮冠状动脉（简称冠脉）腔内球囊成形术（PTCA）患者的冠脉内心电图（IC－ECG）与体表心电图（S－ECG）的对比分析，评价PTCA时的心肌缺血预适应。IC－ECG、S－ECG显示：①球囊第1次扩张时ST段分别上抬21．1±15.3和3．3±1．9mm；第2次扩张时上抬13．1±9．6和2．3±1．2mm；第3次扩张时上抬7．7±7．2和1．9±1．2mm；第4次扩张时上抬4．5±3.9和1．4±0．8mm。每次球囊扩张时IC－ECG与S－ECG上ST段抬高幅值比较差异非常显著（P＜0.005～0．001）。②IC－ECG及S－ECG所示ST段随扩张次数增加呈递减性抬高，第1次扩张分别与第2，3，4次比较P分别＜0.05、＜0．01、＜0．001。结果表明：在PTCA时出现的胸痛逐渐减轻及递减性心肌缺血与心肌缺血预适应有关；与S－ECG比较，IC－ECG更能准确、直观反映球囊扩张时的缺血变化，对评价PTCA时心肌缺血预适应现象有较好的临床应用价值。

Evaluation of Intracoronary Electrocardiography on Ischemia Preconditioning in Percutaneous Transluminal Coronary Angioplasty

Detection of myocardial ischemia during percutaneous transluminal coronary angioplasty(PTCA) is rou-tinely based on surface electrocardiogram (S-ECG) change. To assess myocardial ischemia on intracoronary electro-cardiogram (IC-ECG),IC-ECGs were continuously recorded during the first to the forth balloon inflations;each ofthe inflations was maintained to 60~180 s in 15 patients who had significant stenosis coronary atery. Ten succes-sive QRS-T complexes were analyzed on S-ECGs and IC-ECGs for measurements of ST-segment elevation 80 msafter J point. The mean values of ST-segment shift on the IC-ECG and S-ECG during the first inflation were 21. 1± 15. 3 mm versus 3. 3± 1. 9 mm,the second were 13.1± 9. 6 mm versus 2. 3±1. 2 mm,the third were 7. 7±7. 2mm versus 1. 9±1. 2 mm,the fourth were 4. 5± 3. 9 mm versus 1. 4 ±0. 8 mm (P<0.005~0.001 ). The mean val-ue of ST-segment shift during the second,third and fouth balloon inflation was significantly less than that first in-flation on both IC-ECG and S-ECG(P<0.05,0. 01, 0. 001 ). The findings show that a progressive decrease in chestpain were observed during successive balloon inflations in coronary angioplasty,which suggests a progressive de-crease in myocardial ischemic response. In conculusion,IC-ECG monitoring is more sensitive than S-ECG for de-tecting myocardial ischemia and is easy to use during PTCA.