Impact of coronary calcium score on diagnostic accuracy of multislice computed tomography coronary angiography for detection of coronary artery disease

Background  The impact of the coronary calcium score on the diagnostic accuracy of multislice computed tomography (MSCT) to detect obstructive coronary stenoses remains controversial. Methods and Results  We examined 41 patients (mean Agatston score, 340 ± 530 [range, 0–2546]) with coronary artery disease with 16-slice MSCT and 60 patients (mean Agatston score, 446 ± 877 [range, 0–6264]) with 64-slice MSCT. MSCT scans were analyzed with invasive coronary angiography (CA) as the standard of reference. Lesions with luminal narrowing of 50% or greater were considered obstructive. In total, 9% and 2% of uninterpretable segments were excluded from analysis in patients examined with 16- and 64-slice MSCT, respectively. On a segment basis, the percentage of false-negative segments in the groups with Agatston scores of 0 to 100, 101 to 400, and greater than 400 with 16-slice MSCT were 0%, 5.3%, and 2.9% (P ± .0005), respectively; other comparisons of false-positive and false-negative segments were not significant. The sensitivity and specificity on a vessel and patient basis with 16- and 64-slice MSCT were not significantly different in different calcium score groups. Conclusions  A slight impact of coronary calcium was observed on the diagnostic accuracy of 16-slice MSCT CA on a segment basis, with no significant impact on a vessel and patient basis. No significant impact of coronary calcium was observed on the diagnostic accuracy of 64-slice MSCT CA on a segment, vessel, or patient basis. G.P. is financially supported by the Training Fellowship of the European Society of Cardiology and the Huygens Scholarship, The Netherlands. J.D.S. is financially supported by the Netherlands Heart Foundation, The Hague, The Netherlands (grant No. 2002B105).