[Depression of the ST segment in precordial derivations: prognostic value in inferior myocardial infarct]

We have assessed the prognostic significance of ST segment depression in the anterior precordial leads in patients with an acute inferior infarction. Eighty-four patients with ST segment depression greater than or equal to 1 mm in at least 2 chest leads (Group A) and 82 patients without ST depression (Group B), all admitted to the hospital within 24 hours from the onset of an acute inferior myocardial infarction, were evaluated. Patients with an old infarction, those with intraventricular conduction abnormalities or other causes that could modify the ST segment were excluded from the study. The number of patients affected by complications during the hospital stay was significantly higher in group A (54 patients of group A vs 27 of group B, p less than 0,001). Death, left ventricular failure, ventricular arrhythmias were considerably higher in group A. Moreover we observed that the persistence of the ST segment depression for more than 24 hours identified a subgroup of patients with a very strong risk of complications, particularly death and left ventricular failure. The follow up after 3-6 months, however, did not show any significant difference in both groups. In conclusion, from our study it appears that patients with an inferior infarction precordial ST segment depression have a graver prognosis in the acute phase while their mid-term fate does not seem to be influenced by the presence of this electrocardiographic abnormality.