Optimal criteria for the diagnosis of coronary artery disease by dobutamine stress echocardiography

The diagnosis of coronary artery disease [CAD) on the basis of inducible ischemia in greater than or equal to 2, rather than greater than or equal to 1, segments was suggested to improve specificity of dobutamine stress echocardiography (DSE). However, the impact of using these criteria on the sensitivity and accuracy of DSE was not studied. We studied the accuracy of DSE (up to 40 mu g/kg/min) for the diagnosis of CAD in 290 patients with suspected myocardial ischemia using the criteria of greater than or equal to 1 and greater than or equal to 2 ischemic segments. Ischemia wets defined as new or worsening wall motion abnormalities using a 16-segment model. Among the 85 patients without previous myocardial infarction, significant CAD was detected in 51 (60%). Sensitivity, specificity, and accuracy of DSE using greater than or equal to 1 ischemic segment were 73%, 85%, and 78%, respectively. Those using greater than or equal to 2 segments were 67%, 94%, and 78%, respectively (p = NS). Regional specificity improved by using greater than or equal to 2 segments (91% vs 96%, p <0.05) at the expense of an equivalent reduction in regional sensitivity (60% vs 44%, p <0.05), whereas the regional accuracy was similar (80% vs 79% for greater than or equal to 1 and greater than or equal to 2 segments, respectively). In the 205 patients with previous myocardial infarction, the criterion of ischemia in greater than or equal to 1 segment had a higher sensitivity and accuracy for overall diagnosis of CAD (75% vs 64%, p <0.05; 77% vs 68%, p <0.05), infarct-related CAD (64% vs 47%,p <0.005; 70% vs 57%, p <0.01), and remote CAD (74% vs 57%, p <0.005; 78% vs 69%, p <0.05) than the criterion of greater than or equal to 2 segments, respectively. It is concluded that in patients without previous myocardial infarction, the use of greater than or equal to 2 ischemic segments by DSE for the diagnosis of CAD does not improve the accuracy of DSE compared with the criterion of greater than or equal to 1 ischemic segment. Conversely, in patients with previous infarction the use of greater than or equal to 2 segments reduces the overall and regional sensitivity and accuracy without a significant improvement in specificity. (C) 1998 by Excerpta Medica, Inc.