Decreased [99mTc]Sestamibi uptake with dobutamine versus dipyridamole stress
Sciagrà, R.; Zoccarato, O.; Bisi, G.; Pupi, A.
Quarterly Journal of Nuclear Medicine and Molecular Imaging Official Publication of the Italian Association of Nuclear Medicine and the International Association of Radiopharmacology and Section of the Society Of. 53(6): 671-677
2009
ISSN/ISBN: 1824-4785 PMID: 20016457 Document Number: 632901
Animal studies suggest an interference of dobutamine on [99mTc]sestamibi uptake. In this study dobutamine was compared to dipyridamole rest-stress [99mTc]sestamibi uptake ratio (UR). Twenty-five patients with suspect coronary artery disease (CAD) underwent rest, dobutamine, and dipyridamole [99mTc]sestamibi SPECT at 24-h intervals and coronary angiography. UR was calculated separately for each coronary territory considering injected dose and acquisition delay. There were 38 CAD territories in 20 patients. On a patient basis, dipyridamole SPECT sensitivity was 85%, versus 70% for dobutamine. On a territory basis, sensitivity was 66% versus 42% (P<0.05), and specificity 92% versus 86%, respectively for dipyridamole versus dobutamine. In the 38 CAD territories, dipyridamole UR was -4.1+/-29.4%, and dobutamine UR was -13.1+/-19.9% (P<0.05). In the 37 no-CAD territories, UR was 34+/-23.6% for dipyridamole and -0.4+/-17.8% for dobutamine (P<0.0001). UR difference between CAD versus no-CAD territories was larger using dipyridamole (P<0.0001) than dobutamine (P<0.005). The UR comparison confirms that [99mTc]sestamibi uptake underestimates the blood flow heterogeneity induced by dobutamine more than that produced by dipyridamole.