High Dose Adenosine Stress Echocardiography for Noninvasive Detection of Coronary Artery Disease

The aim of this study was to assess the tolerability and incremental diagnostic value of high adenosine doses in stress echocardiography testing in patients with coronary artery disease (CAD). In comparison with other pharmacologic stress echocardiography tests, standard dose adenosine stress has suboptimal sensitivity for detecting milder forms of CAD. Adenosine stress echocardiography was performed in 58 patients using a starting dose of 100mg/kg body weight per min over 3 min followed by 140mg/kg per min over 4 min (standard dose). If no new wall motion abnormality appeared, the dose was increased to 200mg/kg per min over 4 min (high dose). All patients underwent coronary angiography. Significant CAD was defined as >50% diameter stenosis in at least one major coronary artery. Thirty-three patients had one-vessel and seven had multivessel CAD. Coronary angiographic findings were normal in 18 patients. The high adenosine dose caused a slight but significant increase over baseline values in rate-pressure product. Limiting side effects occurred in two patients during the standard dose protocol and in one patient receiving the high dose regimen. The test was stopped in 30 patients after the standard adenosine dose regimen because of a provoked new wall motion abnormality. The sensitivity of adenosine echocardiography with the standard dose was 75% (95% confidence interval [CI] 63% to 87%). After completion of the standard dose protocol, 28 patients continued testing with the high dose adenosine protocol. The overall sensitivity of adenosine echocardiography, calculated as cumulative, increased to 92% (95% CI 84% to 100%) with the high dose (p