左回旋支作为急性心肌梗死时梗死相关动脉的心电图特征

The electrocardiogram characteristics of left circumflex artery as infarction related artery in acute myocardial infarction

目的分析左回旋支(left circumflex artery,LCX)作为急性心肌梗死(acute myocardial infarction,AMI)时梗死相关动脉(infarct-related artery,IRA)的心电图特征。方法选取AMI时IRA为LCX及右冠(right coronary artery,RCA)的患者94例,对患者的急诊心电图特点进行回顾性分析,分别比较Ⅰ导联及a VL导联、下壁相关导联、胸导联ST段改变情况以及在下壁相关导联都抬高的情况下ST_Ⅱ与ST_Ⅲ的变化关系。结果入组患者中IRA为LCX和RCA的分别为30例和64例。1Ⅰ、a VL导联与IRA相关性分析:IRA为LCX的患者,Ⅰ导联ST段压低3例,不变或抬高27例;IRA为RCA的患者Ⅰ导联ST段压低22例,不变或抬高42例,两组比较,差异有统计学意义(P=0.013);IRA为LCX的患者a VL导联ST段压低3例,不变或抬高27例;IRA为RCA的患者a VL导联ST段压低26例,不变或抬高38例,两组比较,差异有统计学意义(P=0.003)。2Ⅱ、Ⅲ、a VF导联与IRA相关性分析:IRA为LCX的心电图中,下壁导联ST段抬高10例,未抬高20例;IRA为RCA的心电图中,下壁相关导联ST段抬高51例,未抬高13例,两组比较,差异有统计学意义(P<0.01)。在下壁导联均抬高样本中,IRA为LCX者,ST_Ⅱ≥ST_Ⅲ7例,ST_Ⅲ>ST_Ⅱ3例;RCA的样本中,ST_Ⅱ≥ST_Ⅲ15例,ST_Ⅲ>ST_Ⅱ36例,两组比较,差异有统计学意义(P<0.05)。3胸导联ST段变化与IRA的相关性分析,两组差异无统计学意义。结论 AMI时IRA为LCX的急诊心电图可表现为Ⅰ、a VL导联无明显压低,Ⅱ、Ⅲ、a VF导联亦可无明显抬高,而当下壁导联抬高且IRA为LCX时,主要表现为ST_Ⅱ≥ST_Ⅲ。

Objective To analyze the electrocardiogram characteristics of left circumflex artery as infarction related artery（IRA） in acute myocardial infarction. Methods 94 cases of acute myocardial infarction with infarction related artery of left circumflex artery（LCX） and right coronary artery（RCA） patients were collected from January 2010 to July 2013 in Shuguang hospital affiliated to Shanghai uni- versity of traditional Chinese medicine. The emergency electrocardiogram characteristics of were retrospectively analyzed with ST segment changes in lead Ⅰ, aVL; lead of inferior 8wall patients （Ⅱ,Ⅲ,aVF） and chest leads. Comparison of STⅡ and STⅢ was measured under the condition when IRA was LCX or RCA with elevated ST segment in the inferior wall. Results Among the full set of patients with acute myocardial infarction, IRA with LCX counted for 30 cases while IRA with RCA, 64 cases. （i） Correlation analysis of lead Ⅰ, aVL with IRA： Lead Ⅰ depression in IRA-LCX, 3 cases; non-de- pression 27 cases. Lead Ⅰ depression in IRA-RCA, 22 cases ; non-depression 42 cases with statistically significance in two groups （P = 0. 013 ）. Lead aVL depression in IRA-LCX, 3cases ; non-depression 27 cases. Lead aVL depression in 1RA-RCA, 26 cases; non-depression 38 cases with statistically signifi- cance in two groups （P = 0.003 ）. （ii） Correlation analysis of lead Ⅱ, Ⅲ, aVF with IRA： Lead of in- ferior wall elevation in IRA-LCX, 10 cases; non-elevation 20 cases. Lead of inferior wall elevation in IRA-RCA, 51 cases; non-elevation 13 cases with statistically significance in two groups （P 〈 0.01 ）. While ST devated in both IRA for RCA and LCX, IRA-LCX, STⅡ≥STⅢ7 cases; STⅢ 〉STⅡ 3 cases; IRA-RCA, STⅡ≥ STⅢ 15 cases; STⅢ 〉 STB 36 cases with significant statistically meaning （P 〈 0.05）. （iii） Correlation analysis of chest lead V1-V9 for IRA, non-statistically meaning was measured. Con- clusion IRA for LCX in acute myocardial infarction may have such characteristics as neither obvious depression in lead Ⅰ, aVL; nor obvious elevation in lead Ⅱ,Ⅲ, aVF. While both IRA for LCX and RCA with inferior wall elevation , IRA-LCX is likely to be STⅡ ≥ STⅢ.