P6148Visually assessed coronary and cardiac calcium outperforms perfusion data during scintigraphy in the prediction of adverse outcomes

Abstract Background The presence and amount of calcium in the coronary arteries, but also in the heart valves and aorta, has been clearly associated with cardiovascular and all-cause mortality and this information might be prognostically useful during SPECT-CT examinations, where CT images are co-registered for attenuation correction of myocardial perfusion, but then discarded. Objectives This study sought to determine whether the assessment of calcifications of the coronary arteries, cardiac valves and thoracic aorta in the computed tomography images co-registered for attenuation correction during stress-scintigraphy (SPECT-CT) is associated with long-term mortality and cardiac events on top of other available data. Methods Baseline data were collected prospectively on 353 consecutive patients, referred for suspected coronary artery disease (CAD) with no previously known CAD who underwent stress SPECT-CT between Sept 2010 and Oct 2012. Retrospective analysis was performed on follow-up data for outcomes. Results Patients (mean age 72 years. 58% males) had a mean follow-up of 6.4 years, during which 48 died (15 from cardiovascular causes) and 10 had a non-fatal myocardial infarction (MI). Reversible myocardial perfusion defects were detected in 55 patients (15.6%), 39 of whom (11%) had more than mild defects. The presence of an overall visual calcium score >1 in the attenuation correction images was the most strong univariable (hazard ratio 8.99, p<0.0001) and multivariable (hazard ratio 4.76, p<0.0001) predictor of all-cause death or non-fatal MI on top of age, gender, irreversible myocardial perfusion defects and revascularization after the test. Multivariable models Clinical + SPECT + Overall Calcium Ischemic Cardiac Events HR CI (95%) p-value χ2 Age 1.058 1.0234 to 1.093 0.0008 Male gender 1.63 0.88 to 3.024 0.1183 Fixed perfusion defect 3.924 1.63 to 9.426 0.0022 Overall Calcium >1 4.765 2.2 to 10.32 <0.0001 71.69 Kaplan-Meier Conclusions Visual assessment of coronary or overall coronary, cardiac and aortic calcium in the CT images used for attenuation correction during SPECT-CT is feasible, reproducible and strongly associated with hard cardiac events and all-cause death, beyond clinical variables and myocardial perfusion data. This incredibly easy visual calcium assessment does not require additional costs or radiation and may heavily impact on better risk-assessment of patients with suspected CAD undergoing SPECT-CT.