ST segment deviation in acute myocardial infarction with isolated disease of left anterior descending artery

Abstract

To analyze the characteristics of the electrocardiogram (ECG) of left anterior descending coronary artery (LAD) occlusion in patients with acute ST elevation myocardial infarction (STEMI). Patients included were those diagnosed with STEMI in Peking Union Medical College Hospital from January 1996 to March 2009, and underwent coronary angiography (CAG). The infarction related artery (IRA) was LAD, and there were no significant stenosis in left circumflex artery and right coronary artery. A total of 170 cases were consecutively enrolled. They were divided into 2 groups according to occlusive sites of the LAD: LAD proximal (n = 77), LAD medius distal group (n = 93). Standard 18 leads ECG within 12 hours from the onset of STEMI were recorded and ST segment deviation was analyzed quantitatively. Proximal LAD occlusion as IRA was diagnosed with aVL ≥ 0.1 mV, ST aVL > aVR, sum of II, III and aVF STsegment depression ≥ 0.1 mV, in which sensitivity was 39.0%, 37.7% and 50.6%, specificity was 78.5%, 77.4% and 74.2% respectively. Statisticully significance (P < 0.05). Medius-distal LAD occlusion as IRA was diagnosed with no II ST depression, aVF ST depression and sum of II, III and aVF ST segment depression > 0.1 mV, In which sensitivity were 86.0%, 81.7% and 74.2% and the were 31.2%, 48.1% and 50.6% respectively. Statisticully significance (P < 0.05). In STEMI patients with isolated LAD occlusion, ECG can be useful to predict the occlusion site.