Coronary angiography with flat panel digital detectors significantly increases the sensitivity for calcium detection in relation to conventional fluoroscopy: comparison of both systems with intravascular ultrasound.

OBJECTIVE: To compare the sensitivity and specificity for coronary calcium detection of two fluoroscopic systems: 1) conventional system based on image intensifier chains (CONV); and 2) flat panel digital detector (FPDD) system, using intravascular ultrasound (IVUS) as the gold standard.
BACKGROUND: Coronary calcification represents advanced atherosclerotic disease and has implications during coronary interventions. Angiography has been reported to have low sensitivity for calcium detection compared with IVUS.
METHODS: Lesion calcification was assessed by two different fluoroscopic systems (FPDD and CONV), and by IVUS.
RESULTS: In two consecutive periods, a total of 200 consecutive patients were included, 100 in each group. Clinical characteristics were similar, without significant differences between groups. In the CONV group, IVUS detected calcium in 77% of cases, and angiography in 32%. Sensitivity was 41.6% and specificity 91.3%. In the FPDD group, IVUS reported calcification in 79% of patients, and angiography in 57%. Sensitivity was 72% (p < 0.0001 for comparison with CONV) and specificity was 90.4%.
CONCLUSION: The new fluoroscopic systems, based on FPDD, considerably increase the sensitivity for calcium detection without detrimental effect on specificity.