The electrocardiogram (EKG) is one of the most widely used diagnostic tests in clinical medicine and is generally considered to be an excellent means of detecting many important cardiac abnormalities. However, when the EKG is interpreted in the traditional manner, its diagnostic performance is not as good as clinicians might wish. For example, a recent study showed that three sets of commonly used traditional EKG criteria for inferior myocardial infarction (MI) had such low sensitivities that they missed between 66% and 96% of the MIs that they were supposed to detect.1 In contrast, three different sets of vectorcardiographic (VCG) criteria for inferior MI exhibited much better diagnostic performances. The investigators found that the superior performance of the VCG was due to its ability to display information about the contour of the pathway followed by the electrical forces of ventricular depolarization.
Despite the reported advantages of the VCG, it is