The magnitude of the abnormality and the presence of high-risk findings also assist in clinical decision making [62,63]. The data cited below for SPECT or SPECT/CT MPI rest and stress are for patients with known CAD, but no information is available regarding the presence or absence of chest pain in patients included in these studies. A single-center study evaluated 100 consecutive patients referred for SPECT MPI due to either chronic chest pain and no known CAD (55%) and patients with a documented history of myocardial infarction (29%) referred for risk stratification [64]. MPI and poststress and reversible regional wall motion abnormalities on exercise stress Tc-99m- gated SPECT MPI were significant predictors of angiographic disease and add incremental value to MPI for the assessment of angiographic severity [64,65]. In patients with typical angina (high pretest likelihood of disease), stress SPECT MPI is useful for estimating the extent (single vessel versus multivessel disease) and severity of coronary stenosis, which has relevance for prognosis, choice among therapeutic options, and advisability of performing coronary arteriography. A meta- analysis including 114 SPECT studies of patients with suspected or established CAD have shown sensitivity and specificity for the detection of significant CAD and/or myocardial ischemia was 78% and 52%, respectively, with an NPV of 83% [66]. SPECT and CCTA Hybrid SPECT/CCTA combines the anatomical information provided by CCTA with the functional perfusion evidence of SPECT, resulting in an enhanced diagnostic accuracy for detecting significant CAD compared with SPECT and CCTA alone: the sensitivity and specificity of hybrid SPECT/CCTA were 96% and 95%, respectively, compared with SPECT (93% and 79%) and CCTA (98% and 62%) alone [68]. There was 92% agreement on the necessity of revascularization in the treatment decisions based on hybrid SPECT/CCTA versus SPECT and coronary angiography alone [69].
Chronic Chest Pain High Probability of Coronary Artery Disease PCAs. The magnitude of the abnormality and the presence of high-risk findings also assist in clinical decision making [62,63]. The data cited below for SPECT or SPECT/CT MPI rest and stress are for patients with known CAD, but no information is available regarding the presence or absence of chest pain in patients included in these studies. A single-center study evaluated 100 consecutive patients referred for SPECT MPI due to either chronic chest pain and no known CAD (55%) and patients with a documented history of myocardial infarction (29%) referred for risk stratification [64]. MPI and poststress and reversible regional wall motion abnormalities on exercise stress Tc-99m- gated SPECT MPI were significant predictors of angiographic disease and add incremental value to MPI for the assessment of angiographic severity [64,65]. In patients with typical angina (high pretest likelihood of disease), stress SPECT MPI is useful for estimating the extent (single vessel versus multivessel disease) and severity of coronary stenosis, which has relevance for prognosis, choice among therapeutic options, and advisability of performing coronary arteriography. A meta- analysis including 114 SPECT studies of patients with suspected or established CAD have shown sensitivity and specificity for the detection of significant CAD and/or myocardial ischemia was 78% and 52%, respectively, with an NPV of 83% [66]. SPECT and CCTA Hybrid SPECT/CCTA combines the anatomical information provided by CCTA with the functional perfusion evidence of SPECT, resulting in an enhanced diagnostic accuracy for detecting significant CAD compared with SPECT and CCTA alone: the sensitivity and specificity of hybrid SPECT/CCTA were 96% and 95%, respectively, compared with SPECT (93% and 79%) and CCTA (98% and 62%) alone [68]. There was 92% agreement on the necessity of revascularization in the treatment decisions based on hybrid SPECT/CCTA versus SPECT and coronary angiography alone [69].