Abstract 14825: Assessment of Coronary Artery Stent Restenosis Using 256-Multislice Computed Tomography (256-MSCT): factors affecting assessment and accurate diagnosis using clinical data and phantom study.
Background: Detection of in-stent restenosis (ISR) with cardiac CT would be a major advance for the evaluation of patients suspected of having ISR. However, the diagnostic accuracy and influencing factors of current generation 256-MSCT is not fully established. The purpose of this study was to evaluate the accuracy of 256-MSCT in identifying ISR.
Methods: Between December 2008 and January 2011, 209 consecutive patients (male 79%, mean age 68 years) with prior coronary stent implantation in 449 lesions underwent MSCT (Brilliance iCT v3.0.0, Philips) and coronary angiography. Possible factors that influenced the diagnostic performance of CT were evaluated, which were stent characteristics, stent size, location and heart rate. Three different types of stents (Cypher: Johnson & Johnson, Driver: Medtronic, Vision: Abbott) placed in plastic tubes filled with contrast agent were imaged with MSCT in orientations of 0°, 45°, and 90° relative to the z-axis and in different heart rate, and different size of these stent were imaged. Phantom study indicated that high heart rate and stent diameter affected image quality.
Results: In total, 375(83.9%) stents were available for evaluation. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were 94.6%, 93.3%, 82.2%, and 98.1%. In stents with a diameter ≤2.5 mm, 75(63.6%) of 118 stents were available for evaluation and PPV and NPV were 83.3% and 98.2%. Cypher, Taxus Express2, Taxus Liberte/Liberte and Endeavor/Driver Stent evaluable rate were 82.5%, 82.9%, 84.8% and 90.0%. Evaluable rate of stents in left main coronary artery (LMCA), left anterior descending artery (LAD), left circumflex (LCX) and right coronary artery (RCA) were 91.7%, 86.1%, 75.9% and 85.1%. Evaluable rate, PPV and NPV were over 80%, 84% and 98% in normal heart rate (<80bpm), 72%, 57% and 91% in high heart rate (>or=80bpm).
Conclusions: 256-MSCT angiography has high diagnostic value for detection of coronary in-stent restenosis. However stent diameter, stent lesion, high heart rate (>or=80bpm) and coronary calcification influence accuracy. The diagnostic accuracy of 256-MSCT is not too affected by heart rate (<80bpm) and stent type.
- © 2011 by American Heart Association, Inc.