The Synergistic Use of Coronary Artery Calcium Imaging and Noninvasive Myocardial Perfusion Imaging for Detecting Subclinical Atherosclerosis and Myocardial Ischemia

Abstract

This review aims to assess the synergistic use of coronary artery calcium (CAC) scanning and stress-rest SPECT myocardial perfusion imaging (MPI) for the workup of patients with suspected coronary artery disease (CAD). The CAC score bears a proportional relationship to both the frequency of obstructive CAD and inducible ischemia. Consequently, the test can be used to improve the Bayesian assessment of pre-test CAD likelihood and assist in triaging patients for stress testing. The CAC score and MPI findings are synergistic for predicting cardiac risk, which increases for patients with abnormal MPI studies who also have CAC abnormality. CAC scanning also improves the diagnostic sensitivity of SPECT-MPI by identifying normal SPECT-MPI patients with subclinical atherosclerosis. Finally, CAC scanning helps improve the interpretation of borderline SPECT-MPI scan abnormalities. Combined, these findings indicate a clear benefit for incorporating CAC scanning into the diagnostic workup of patients who are candidates for the evaluation of chest pain symptoms by SPECT-MPI.