title: Usefulness of continuous ST monitoring in inferior wall acute myocardial infarction for describing the relation between precordial ST depression and inferior ST elevation.
abstract: To explore the relation between precordial and inferior ST-segment changes within individual patients, continuous 12-lead electrocardiographic recording was performed in 19 patients with acute inferior infarction given intravenous thrombolytic therapy. Monitoring was performed for 519 +/- 269 minutes. The extent of inferior ST elevation varied considerably with time in all patients. With use of the maximal precordial ST depression recorded to classify patients, 11 had precordial ST depression (sigma V1-3) > 0.2 mV (group A) and 8 had < or = 0.2 mV or no precordial ST depression (group B). The maximal recorded precordial ST depression correlated inversely with the corresponding inferior ST elevation in the 19 patients (r = -0.78, p < 0.001). Within individual patients, continuous 12-lead monitoring revealed a close negative correlation between the inferior and precordial ST levels for the entire recording period in many patients, but 5 of the 19 patients (26%) (2 in group A and 3 in group B) did not have this relation. Moreover, precordial ST depression was not always present during inferior ST elevation in group A patients: 4 of 11 (36%) had some electrocardiographs showing < 0.1 mV precordial ST depression despite summed inferior ST elevation > 0.6 mV. These data indicate that precordial ST depression is not just the simple electrical reciprocal projection of the abnormal inferior wall ST vector, and its fluctuation cannot be predicted by changes in inferior ST level in every patient.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Hallstrom Institute of Cardiology, University of Sydney, Royal Prince Alfred Hospital, Australia.
authors.forename: C K
authors.initials: CK
authors.lastname: Wong
authors.forename: S B
authors.initials: SB
authors.lastname: Freedman
mesh_terms: D000328:Adult; D000368:Aged; D017023:Coronary Angiography; D004562:Electrocardiography / Q000295:instrumentation / Q000379:methods / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic; D009203:Myocardial Infarction / Q000175:diagnosis* / Q000188:drug therapy / Q000453:epidemiology; D012044:Regression Analysis; D012815:Signal Processing, Computer-Assisted; D013300:Streptokinase / Q000627:therapeutic use; D015912:Thrombolytic Therapy; D013997:Time Factors; D010959:Tissue Plasminogen Activator / Q000627:therapeutic use
chemical_list: D013300:Streptokinase; D010959:Tissue Plasminogen Activator