[The relationship between conventional ECG and the culprit coronary artery in acute myocardial infarct].
OBJECTIVE
To evaluate electrocardiogram (ECG) in detecting acute myocardial infarction (AMI) during the first 12 hours of symptoms and its relationship to the culprit coronary artery.


METHODS
We studied 68 patients aged 55.6 (30 to 76) years, 61 males, with AMI confirmed by elevated CKMB isoenzyme and cinecoronariography (CINE). In all of them we obtained two ECG: first (i), with < 12 hours of symptoms and a second, > or = 5 days during evolution. ECG were analyzed in order to disclose up and downward ST-T segments > or = 1 mm, new Q waves > or = 0.04 s and R/S > or = 1 plus downward ST-T segment in leads V1 and V2. Then we have done correlation between these and the culprit coronary lesions at CINE.


RESULTS
The culprit coronary lesions were: right coronary artery (RCA) in 16, left circumflex (LC) in 26 and left anterior descending (LAD) in 31 cases. According to the ECG, the RCA determined inferior AMI in all patients and the LC only in 62% of cases. Posterior AMI due to LC was seen in 81% of cases at ECG and, associated with lateral AMI, in 52%. Lone lateral AMI was seen in 5% and true posterior in 14% of cases, all of them due to LC.


CONCLUSIONS
False negative ECG (i) in AMI is in fact due to LC occlusion which, frequently, causes posterior wall more then inferior wall myocardial infarction at ECG.
César
L A
LA
Instituto do Coração, Hospital das Clínicas, FMUSP, San Paulo.
Moretti
M A
MA
Ramires
J A
JA
Nussbacher
A
A
Consolim
F M
FM
Moffa
P J
PJ
da Luz
P L
PL
Bellotti
G M
GM
Pileggi
F
F
D000328:Adult; D000368:Aged; D002932:Cineangiography; D004796:Clinical Enzyme Tests; D017023:Coronary Angiography; D003402:Creatine Kinase / Q000097:blood; D004562:Electrocardiography; D005260:Female; D006801:Humans; D007527:Isoenzymes; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000175:diagnosis* / Q000209:etiology; D013997:Time Factors
D007527:Isoenzymes; D003402:Creatine Kinase
Relação entre o ECG convencional e a artéria coronária responsável no infarto agudo do miocárdio.