AHA/ACCF/HRS Recommendations for the Standardization and Interpretation of the Electrocardiogram: Part VI: Acute Ischemia/Infarction

February 19, 2009—This is the sixth and final section of the project to update electrocardiography (ECG) standards and interpretation. The following topics are discussed: 1) the meaning and importance of both ST-segment elevation and depression; 2) the concept of anatomically contiguous leads; 3) the threshold values for ST-segment changes; 4) the use of the ST-segment spatial vector to determine the region involved and the occluded coronary artery; 5) the importance of postischemic T-wave changes; 6) the diagnosis of ischemia/infarction in the presence of intraventricular conduction disturbances; and 7) quantitative QRS changes for estimation of chronic infarct size.