Influence of thrombolytic therapy on inferior acute myocardial infarction with concomitant anterior ST segment depression

The purposes of this study were to analyze the prognostic significance of p recordial ST segment depression and to determine whether thrombolytic thera py is effective for all patients with inferior acute myocardial infarction (AMI) or whether there is a different effectiveness for patients with conco mitant anterior ST segment depression persisting for 24 hours or longer. Me dical charts of 176 patients were studied. On the basis of ECG the patients were subclassified into three groups according to the presence, persistenc e, or absence of significant ST segment depression: Group 1: anterior ST se gment depression persisting for less than 24 hours (45.4%); Group 2: anteri or ST segment depression persisting for more than 24 hours (17.6%); Group 3 : no anterior ST segment depression (37%). Age, Killip class, peak creatine kinase, hospital deaths, left ventricular ejection fraction, regional wall motion score, postinfarction angina, and ventricular/supraventricular arrh ythmia of all patients were studied. Parameters of the three groups were co mpared: worse results were found in group 1 and the worst in group 2. This result is independent of thrombolytic therapy. Finally, the same parameters of thrombolyzed and nonthrombolyzed groups were compared: no statistically significant difference was observed. Among thrombolyzed patients the numbe r of those with ST depression lasting more than 24 hours is lower than in n onthrombolyzed patients. It can be assumed that thrombolytic therapy in inf erior AMI determines a shifting of patients from a worse prognosis group (S T segment depression persisting for more than 24 hours) to a better prognos is group (ST segment depression persisting for less than 24 hours).