TY - JOUR T1 - Attenuation of Adenosine-Induced Myocardial Perfusion Heterogeneity by Atenolol and Other Cardioselective β-Adrenoceptor Blockers: A Crossover Myocardial Perfusion Imaging Study JF - Journal of Nuclear Medicine JO - J Nucl Med SP - 1036 LP - 1043 DO - 10.2967/jnumed.109.073411 VL - 51 IS - 7 AU - Eliana Reyes AU - James Stirrup AU - Michael Roughton AU - Savio D'Souza AU - S. Richard Underwood AU - Constantinos Anagnostopoulos Y1 - 2010/07/01 UR - http://jnm.snmjournals.org/content/51/7/1036.abstract N2 - Little is known about the effect of chronic β-blockade on adenosine actions. We sought to investigate the effect of oral β-blockers on the presence, extent, and severity of myocardial perfusion abnormality induced by adenosine in patients with coronary artery disease. Methods: In this crossover study, 45 male patients with coronary artery disease on β-blocker therapy with atenolol, bisoprolol, or metoprolol underwent adenosine myocardial perfusion imaging both on and off β-blockade in a random order on separate days. Myocardial perfusion was assessed both qualitatively and quantitatively. Hemodynamic response, image analysis, and sensitivity for the detection of coronary stenosis (≥50% luminal diameter reduction on x-ray coronary angiography) were compared between the on and off β-blocker studies. Results: Rate pressure product both at baseline and at peak adenosine infusion decreased by 23% ± 15% and 21% ± 18%, respectively, after β-blockade (P < 0.001 for all). The median (interquartile range) summed difference score, a measure of defect reversibility, and quantitative defect size were both significantly lower after β-blockade (median, 7.0 [interquartile range, 2.0–9.5] vs. median, 5.0 [interquartile range, 0–8.0], P = 0.002; and quantitative defect size, 18% [interquartile range, 9%−34%] vs. quantitative defect size, 6% [interquartile range, 0%−19%], P < 0.001, respectively). The overall sensitivity for the detection of coronary stenosis decreased from 0.76 (95% confidence interval, 0.65–0.88) to 0.58 (95% confidence interval, 0.45–0.71) after β-blockade (P = 0.03). Conclusion: β-blockade causes a small but significant reduction in the extent and severity of perfusion abnormality by adenosine. This may reduce the diagnostic sensitivity of adenosine myocardial perfusion imaging for the detection of flow-limiting coronary stenosis. ER -