Background: Our aim was to develop a normal database to be used for quantification of myocardial perfusion and diagnosis of "obstructive coronary artery disease" (CAD) using low-dose rubidium-82 three-dimensional (3D) positron emission tomography (PET)-CT.
Methods: From a record of 1,501 patients, 77 were identified as having low-likelihood (LLK) of CAD. Forty LLK patients were used to construct a normal database using 4DM-PET, the remainder used for validation of normalcy. A group of 70 patients with CAD who had invasive coronary angiography and PET-CT were used to evaluate the accuracy of the database for detecting CAD using the sum-stress-score. The effect of clinical exclusion criteria and the inclusion of LLK patients were evaluated.
Results: The normal database for CAD detection had a normalcy rate of 95%. Sensitivity was 100% for detecting patients with either 50% or 70% stenosis. Optimal specificity was 87% for either 50% or 70% stenosis. For localizing disease at 50% stenosis in the left anterior descending, left circumflex, and right coronary artery, sensitivity ranged from 59% to 68%, while specificity was maintained at 87-89%. Similarly, at 70% stenosis, sensitivity ranged from 64% to 79%, and specificity from 87% to 91%.
Conclusions: A normal database containing the relative perfusion scores of patients with LLK of CAD can be used to accurately diagnose obstructive coronary disease using low-dose Rb-82 with 3D PET-CT imaging.