Early Diagnosis and Exclusion of Acute Myocardial Infarction by Two Hours' Vector-ECG and Determination of Either Myoglobin or CK-mb

Abstract

This retrospective study assesses the early diagnostic potential of a combination of multilead continuous vectorcardiography (VCG) and biochemical markers (myoglobin, troponin-t and CK-mb mass) in patients with chest pain who present with suspected acute myocardial infarction (AMI), but without ST-elevation on resting 12-lead ECG on admission. Within a multicenter study 56 patients admitted for chest pain (<12 h) and with a non-diagnostic 12-lead ECG on admission and a VCG recording were included. Venous blood samples were drawn on admission and the continuous VCG was monitored for 2 h. The results were related to the clinical diagnosis of AMI. Neither the biochemical markers nor VCG alone permitted the diagnosis or exclusion of AMI at admission. However, if either analysis of myoglobin on admission or 2 h of VCG recording were positive, they would have a sensitivity for detection of AMI of 100% and specificity of 69%. In a subset of patients with more than 4 h delay since start of chest pain, CK-mb could replace myoglobin and give a sensitivity of 100% and a specificity of 81%. Determination of myoglobin or CK-mb at admission and VCG monitoring for 2 h can reliably confirm or exclude AMI within 2 h. This combination seems useful for early stratifications of patients in chest pain or coronary care units.