Abstract
Background Whether or not patients with coronary artery disease (CAD) could be easily detected at the bedside using dipyridamole stress was investigated using a portable type signal-averaged electrocardiography (portable SAECG). Methods and Results The standard 12-lead QRS wave SAECG was performed at the bedside before and after dipyridamole stress in 30 patients with angiographically significant stenotic lesions, who had positive myocardial ischemia in the dipyridamole-thallium myocardial perfusion imaging (CAD group), and 33 patients with no significant stenotic lesions, who had negative imaging (control group). The filtered QRS duration (fQRSd) before and after dipyridamole stress was determined by the vector magnitude method and the difference (ΔfQRSd) was obtained. Furthermore, the ΔfQRSd was obtained using the multiphasic oscillation method, as well at the same standard 12-lead, and the maximal value of changes in fQRSd (MAX ΔfQRSd) between the 12 leads was determined. The ΔfQRSd was similar between 2 groups (p=0.11). The MAX ΔfQRSd associated was significantly greater in the CAD group (p<0.0001). When a cut-off value of MAX ΔfQRSd ≥ 5 ms was used for the detection of CAD, the sensitivity and specificity were 97 and 94%, respectively. Conclusion The portable dipyridamole-stress SAECG easily detect CAD and myocardial ischemia at the bedside. (Circ J 2005; 69: 659 - 665)
