Abstract 16515: Detection of Luminal Stenosis by 320-slice CT in Coronary Arteries with Cross Sectional Area Less Than 4mm2 Confirmed by Intravascular Ultrasound Compared with Conventional Coronary Angiogram
Purpose: To evaluate the diagnostic accuracy of detection of luminal stenosis by 320 slice CT in coronary arteries with cross sectional area (CSA) < 4mm2 confirmed by intravascular ultrasound (IVUS) by 320 slice CT compared with conventional coronary angiogram (CAG).
Materials and Methods: Of 86 subjects who underwent both 320 slice CT and CAG within 6 months, 22 consecutive subjects were enrolled (17 males, mean age 66±10 yrs, mean heart rate 60±14 beats/min, hypertension 55% hyperlipidemia, 46% diabetes mellitus, 32% median Agatston calcium score 198) who had >75% or >90% stenosis on CAG according to the American Heart Association classification (corresponding to >50% and >75%, respectively, on quantitative coronary angiogram). We determined whether CSA was <4mm2 by IVUS with 40MHz.
Results: Among 133 segments from 26 vessels, >50% and >75% luminal stenosis on CT were observed in 42 and 32 segments, respectively, >75% and >90% stenosis on CAG were observed in 47 and 39 segments, respectively, and CSA <4mm2 in IVUS was observed in 41 segments. In a segment by segment analysis, sensitivity, specificity, positive (PPV) and negative predictive values (NPV) of >50% stenosis on CT for predicting CSA <4mm2 in IVUS were 95, 97, 93, and 98%, respectively, of >75% stenosis on CAG for predicting CSA <4mm2 in IVUS were 93, 90, 81, and 97%, respectively, and there were no significant differences between CT and CAG. Sensitivity, specificity, PPV and NPV of >75% stenosis on CT for predicting CSA <4mm2 in IVUS were 76, 99, 97, and 90%, respectively, of >90% stenosis on CAG for predicting CSA <4mm2 in IVUS were 85, 96, 90, and 94%, respectively, and there were no significant differences between CT and CAG. Sensitivity and NPV were higher and specificity and PPV were lower for >50% stenosis than >75% stenosis on CT, but absolute values were high in both groups.
Conclusions: Diagnostic accuracy of detection of luminal stenosis with CSA <4mm2 in IVUS by >50% or 75% stenosis on 320 slice CT were as high as CAG.
- © 2010 by American Heart Association, Inc.