Abstract 4220: Low Calcium Score Does Not Exclude Significant Coronary Stenosis in Women at Intermediate Risk

Abstract

Introduction : Coronary calcium deposition is associated with atherosclerosis and its quantification provides independent and incremental information to the clinical risk assessment. In women with low to intermediate clinical risk, how well zero or low calcium score predicts the absence of obstructive coronary artery disease (CAD) has not been elucidated. Hypothesis : To examine the extent of CAD on 64-slice multidetector computed tomography (MDCT) coronary angiography in women with zero or low calcium score. Methods : We studied 495 consecutive patients referred to coronary MDCT for clinically suspected CAD. Of these we identified 184 women with low to intermediate risk of CAD who had zero or low calcium score. A low calcium score was defined as an Agatston score of 1–100. Luminal stenosis of 50% or more was considered as obstructive CAD. Prevalence and severity of CAD were assessed and analyzed on per patient basis. Results : Calcium scores of 0 and 1–100 were found in 101 and 83 patients respectively. Patients with zero calcium score were younger (54.92 ± 10.34 vs. 61.21 ± 10.25 years, p = 0.0001), but none of the risk factors showed a significant difference as compared to patients with score of 1 - 100. Obstructive CAD was present in 4 patients (3.9%) with 0 calcium score as compared to 21 patients (22.9%) with calcium score of 1 - 100. (p = 0.0001) Later group also had more extensive disease, i.e., 2 patients had 3-vessel disease, 2 had 2-vessel disease. (p=0.05) Conclusions: In women with low to intermediate risk, although zero calcium score markedly reduces possibility of significant CAD; low calcium scores are significantly less predictive of prevalence or severity of underlying CAD. Low calcium score does not preclude the need for further assessment and MDCT coronary angiography might be a useful noninvasive imaging modality in this population.