Analysis of electrocardiogram of acute inferior myocardial infarction with chest lead ST segment changes / 中国综合临床

ABSTRACT

Objective To investigate the association between chest ST segment descent in patients with acute inferior myocardial infarction (AIMI) and myocardial infarction in other area, QT dispersion, severe auriculoventricular block (AVB) serious ventricular arrhythmia. Methods According to persistent time of chest lead ST segment descent,74 patients of acute inferior myocardial infarction with chest lead ST segment descent were divided into 2 groups: ≥24 h (group Ⅰ ,44 cases), ＜ 24 h (group Ⅱ ,30 cases). The occurrence of other areas of myocardial infarction, QTd, auricular-ventricular block and serious ventricular arrhythmia were compared between the two groups. Results Chest ST segment descent occurred in 33 cases in group Ⅰ (75%) ,in 7 cases in group Ⅱ ( 23% ), with significantly difference between the two groups ( χ2 = 19. 17, P ＜ 0. 01 ). QTd was (74. 77 ± 23.28) ms in group Ⅰ which was significantly higher than that of (50. 00 ± 11:45 ) ms in group Ⅱ ( t =5.39,P ＜0. 01 ). Auricular-ventricular block (grade Ⅱ and Ⅲ ) occurred in 20 cases in group Ⅰ (45%),and in 5 cases in group Ⅱ ( 17% ), with significant difference between the two groups (χ2 = 9.43, P ＜ 0. 05 ). Twentyone cases with serious ventricular arrhythmia occurred in group Ⅰ (48%) ,which was significantly higher than that in group Ⅱ (4 cases, 13% ) ( χ2 = 6. 61, P ＜ 0. 01 ) . Conclusion When persistent time of acute inferior myocardial infarction with chest lead ST segment descent is longer than 24 hrs, the area of myocardial infarction is more extensive, QT dispersion increases, the occurrence of serious ventricular arrhythmia and auricularventricular block also significantly increase.