Résumé
Objective To evaluate clinical significance of ischemia grade to predict severe arrhythmia in patients with acute ST-segment elevation myocardial infarction(STEMI).Methods A total of 225 patients with STEMI admitting to emergency department were enrolled.All enrolled patients were divided into two groups based on the QRS complex electrocardiogram on admission:grade 1Ⅱ ischemia group(135 cases) and grade Ⅲ ischemia group (90 cases).All patients received thrombolytic therapy.The incidence rate of ST segment resolution (STR) and severe arrhythmia in hospital stay was observed.Results The ST segment elevation (Σ.ST) on admission and 2 h after thrombolysis in grade Ⅲ ischemia group was significantly higher than that in grade Ⅱ ischemia group [(0.84 ± 0.57) mV vs.(0.44 ± 0.35) mV,(0.50 ± 0.23) mV vs.(0.11 ± 0.06) mV] (P ＜ 0.01).The backing rate of ST segment ≥ 50％ 2 h after thrombolysis in grade Ⅲ ischemia group was significantly lower than that in grade Ⅱ ischemia group [56.7％ (51/90) vs.83.7％ (113/135)] (P ＜0.01).The creatine kinase MB (CK-MB) peak value in grade Ⅲ ischemia group was significantly higher than that in grade Ⅱ ischemia group [(363 ± 105) U/L vs.(212 ± 97) U/L] (P ＜ 0.01).There was no significant difference in the incidence of severe arrhythmia between two groups (P ＞ 0.05).Multiple Logistic regression analysis demonstrated that the independent predictors of severe arrhythmia were duration from symptom to thrombolysis and initial ΣST,whereas grade Ⅲ ischemia remained a strong predictor of severe arrhythmia.Conclusion Grade m ischemia on admission is associated with lower incidence of STR in patients with STEMI after thrombolysis and a strong predictor of severe arrhythmia.