Correlación angiográfica del descenso del segmento ST con el ejercicio en derivaciones precordiales después de un infarto agudo de miocardio inferior

Abstract

This study was aimed to establish the angiographic correlation of the exercise-induced ST segment depression in precordial leads after an uncomplicated inferior wall myocardial infarction. We studied retrospectively 67 patients with a recent inferior wall acute myocardial infarction who took an exercise stress test following Bruce protocol and a coronary angiography within 3 months. Four groups were defined according to the ST segment response to exercise: group I, no ST segment changes; group II, ST depression in leads V1-V4; group III, ST depression in leads V5-V6; and group IV, ST depression in leads V1-V6. There were no significant differences among the groups for clinical and exercise variables, except for age (groups I and II were significantly younger than groups III and IV). The prevalence of multivessel coronary artery disease (two- and three-vessel disease) was 21%, 18%, 52% and 72% for group I to IV respectively (p = 0.007). The prevalence for left anterior descending coronary artery disease was 5%, 9%, 35% and 50% for group I to IV respectively (p = 0.01). By multivariate logistic regression analysis, only age > 60 years (p = 0.002) and exercise group III and IV (p = 0.02) were independent predictors for the presence of multivessel coronary disease. Whereas an ST exercise response type I or II in a patient < or = 60 years virtually excluded the presence of multivessel disease (negative predictive value, 0.90), an ST exercise response type III or IV in a patient > 60 years strongly suggested the presence of multivessel disease (positive predictive value, 0.72). Age and exercise-response of ST segment in precordial leads are useful variables for predicting the presence or absence of multivessel coronary artery disease after an uncomplicated inferior wall acute myocardial infarction.