This study correlated the electron beam computed tomographic (EBCT) calcium scores
with the results of coronary angiography in symptomatic patients in order to assess
its value to predict or exclude significant coronary artery disease (CAD).
Electron beam computed tomography is a sensitive method to detect coronary calcium.
However, it is unclear whether it may play a role as a filter before invasive procedures
in symptomatic patients.
A total of 1,764 patients (1,225 men and 539 women) with suspected CAD from a single
center were included in our study. All patients underwent calcium screening with EBCT
(C150XP Imatron) and conventional coronary angiography.
Fifty-six percent of men and 47% of women revealed significant coronary stenoses (>
or =50%). Total exclusion of coronary calcium (14% of the study group) was associated
with an extremely low probability of stenosis (<1%). With calcium scores > or =20th,
> or =100th or > or =75th percentile of age groups, the sensitivity to detect stenoses
decreased to 97%, 93% and 81%, respectively, in men and to 98%, 82% and 76%, respectively,
in women. At the same time, the specificity increased up to 77% in men and women.
There was a significant difference in coronary calcium between men and women in all
age groups; however, receiver-operating characteristic curves indicated that the test
can be performed with equal accuracy in all of these subgroups.
Calcium screening with EBCT is a highly sensitive and moderately specific test to
predict stenotic disease. Exclusion of coronary calcium defines a substantial subgroup
of patients, albeit symptomatic, with a very low probability of significant stenoses.