Abstract
BACKGROUND: Even in asymptomatic patients, there is a high association of ischemia on myocardial perfusion scans in those with coronary artery calcification or valvular calcifications. Patients without coronary artery calcifications have exceeding-low rates of cardiovascular events. The absence of cardiovascular calcification, including coronary artery, valvular, and thoracic aorta is a strong negative predictor of myocardial ischemia. In individuals with suspected ischemia who had chest computed tomography imaging, evaluation for cardiovascular calcification (coronary artery, valves, and thoracic aorta) is an invaluable tool to guide management for further diagnostic imaging. We hypothesize that the complete absence of cardiovascular calcification has a high negative predictive value for defects in myocardial perfusion imaging such as single-photon emission computed tomography (SPECT) or positron emission tomography (PET). METHODS: Non-contrast computed tomography performed for SPECT/PET CT attenuation correction from March 1, 2017, to September 30, 2017, were retrospectively reviewed for the absence of cardiovascular calcification by a cardiologist and radiologist who were blinded to patients' medical history. Medical records were reviewed to include patient demographics and medical history. A total of 132 patients were analyzed. RESULTS: Of the 132 patients without calcifications, seven patients had small myocardial perfusion defects suggestive of ischemia or infarct, but none were considered significant defects. Of these seven patients, six were managed medically and one was from an outside institution with no follow-up data. Two of the seven patients had follow-up invasive angiography or coronary CTA that did not show significant atherosclerotic coronary artery disease. CONCLUSION: A complete absence of cardiovascular calcification indicates a 100% negative predictive value for a significant perfusion defect on same-day confirmatory nuclear stress testing. Patients with suspected ischemia but absent cardiovascular calcifications can be safely managed medically without further testing for ischemia.