RESUMO
In order to enhance subtle changes not apparent in resting ECGs by conventional criteria, a computerized signal processing technique, biopotential coordinate transformation (BCT), has been developed to increase the physician's perceptibility of CAD in seemingly "normal" resting ECGs. ECGs initially read as normal then can be tested with this process to predict the presence or absence of CAD. A blinded, retrospective study of 93 Caucasian patients with normal ECGs was performed using coronary angiography as the test standard. The BCT process identified the presence or absence of CAD with an 84.3% sensitivity and 81.8% specificity in 62 men. Similarly, a 76.2% sensitivity and 80% specificity was obtained for 31 women. These results suggest that the BCT process may provide the emergency physician with a noninvasive screening test for the detection of CAD in patients with apparently normal resting ECGs. Further studies are necessary for process refinement and verification.
