The relationship of coronary flow reserve (CFR) to stress thallium-201 myocardial perfusion (T1) and radionuclide ventriculography (RNV)

Coronary arteriography (CA) can be used to delineate the abnormal anatomy in coronary artery disease (CAD), but the degree of the impairment of coronary blood flow (CBF) cannot be predicted precisely by CA. As a reduction in maximal hyperemic blood flow (MHBF) characterizes a functionally significant coronary lesion, the ratio of contrast-induced MHBF to basal CBF: the coronary flow reserve (CFR) reflects the physiologic significance of a coronary lesion. Recent developments in digital coronary angiography allow CFR to be measured at CA. To assess the relationship of CFR to other noninvasive tests of myocardial perfusion and function the results of stress T1 and RNV were compared to those of CA and CFR for the distribution of 48 arteries in 20 patients. Seven patients had normal CA without spasm: 3 with abnormal CFR had a discrete T1 defect or global RNV dysfunction. The remaining 4 had normal CFR, T1 and RNV. Thirteen had CAD without prior infarction. Segmental T1 and RNV were compared to CA and CFR. Normal CFR was seen in patients with both normal T1 and RNV; while T1 was best associated with abnormal CFR in CAD and may be the preferable noninvasive modality to identify physiologically significant, abnormal CBF in suspected cases of CAD