Correlation between electrocardiographic subtypes of anterior myocardial infarction and regional abnormalities of wall motion.

BACKGROUND: Examination of the electrocardiogram is the most widely used means for diagnosis and early stratification of risk of acute myocardial infarction (AMI). The classical classification of the subtypes of anterior AMI is based on results of studies comparing the electrocardiograms recorded at various stages, mostly in the subacute or chronic stage of AMI, with autopsy findings. Reports regarding the correlation between electrocardiographic findings in the acute phase and regional abnormality of wall motion (AWM) detected by echocardiographic evaluation are sparse.

OBJECTIVE: To investigate the relationship between the electrocardiographic and two-dimensional echocardiographic findings regarding patients with their first anterior AMI.

DESIGN AND METHODS: We studied 58 patients, 44 men and 14 women of mean age 61.5 +/- 14.6 years, with their first anterior AMI who had undergone two-dimensional echocardiographic evaluation within 48 h of admission. Deviation of ST-segment trace from baseline was measured manually 0.06 s after the J point for all leads on the admission electrocardiogram. ST-segment elevation in the various leads was correlated to the incidence of regional AWM detected by echocardiography.

RESULTS: ST-segment elevations > or = 0.1 mV in V1 leads were found for 21 (36.2%) patients. Basal anterior, basal anteroseptal, and basal septal AWM were seen more often for patients with than they were for patients without ST-segment elevation in V1 (57 versus 16%, P=0.003; 43 versus 13.5%, P=0.03; 43 versus 11%, P=0.01 respectively). In contrast to ST-segment elevation in lead V1, the only statistically significant difference in prevalence in the presence of regional AWM between patients with (n = 48) and without (n = 10) ST-segment elevation > or = 0.2 mV in lead V2 was in the inferoapical region (87.5 versus 40%; P=0.003). ST-segment elevation > or = 0.1 mV in leads aVL and V5 was found for 11 (19%) and 23 (40%) patients, respectively. There was no correlation between either lateral or apical regional AWM and the presence of ST-segment elevation in the anterolateral leads except for mid-lateral AWM, which was more often detected for patients with than it was for patients without ST-segment elevation in aVL leads (36.3 versus 6.4%, P=0.026).

CONCLUSIONS: ST-segment elevation in lead V1 during the acute phase of anterior AMI is associated with a high incidence of regional AWM in the basal anterior, anteroseptal, and anterior regions, whereas ST-segment elevation in lead V2 is more often associated with AWM in the inferoapical region. ST-segment elevation in aVL leads is related to mid-lateral regional AWM.