Calcification Remodeling Index Characterized by Cardiac CT as a Novel Parameter to Predict the Use of Rotational Atherectomy for Coronary Intervention of Lesions with Moderate to Severe Calcification

Figures

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  Fig. 1. Flow chart of patient inclusion and exclusion. CCTA = coronary computed tomography angiography, ICA = invasive coronary angiography, PCI = percutaneous coronary intervention

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  Fig. 2. Illustration of calculation of calcification remodeling index. Index was defined as ratio of lumen area (with inclusion of calcium) of most severely calcified site versus lumen area of proximal reference.

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  Fig. 3. Representative case of calcified coronary stenosis treated with RA and PCI. A. 3D-MIP image of left coronary artery showing calcified lesion located at LM and proximal LAD (white arrow). B. Calcification length measured on CPR image (white arrow) was 12.2 mm. Calcium volume and focal Agatston score were 191.8 mm3 and 256.3, respectively. Calcification remodeling index of this lesion was calculated to be 0.47. Involved calcium arc quadrant was 3 as identified on cross-sectional images. C. Fluoroscopy of left coronary artery revealing calcification of proximal LAD (white arrow). D. ICA of left coronary artery showing severe stenosis of proximal LAD (white arrow). E. Lesion was modified with RA (white arrow) prior to stent deployment. F. Lesion was successfully treated after stent implantation as confirmed by ICA (white arrow). CPR = curved planar reformation, LAD = left anterior descending, LM = left main, MIP = maximum intensity projection, RA = rotational atherectomy

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  Fig. 4. Representative case of calcified coronary stenosis treated with PCI but without RA. A. 3D-MIP image of left coronary artery showing long diffusely calcified lesion located at proximal to middle LAD (white arrows). B. Calcification length measured on CPR image (white arrow) was 38.2 mm. Calcium volume and focal Agatston score were 782.9 mm3 and 977.6, respectively. Calcification remodeling index of this lesion was calculated to be 0.91. Involved calcium arc quadrant was 2 as identified on cross-sectional images. C. Fluoroscopy of left coronary artery revealing calcification of proximal to middle LAD (white arrows). D. ICA of left coronary artery showing severe stenosis of proximal LAD (white arrow). E. Lesion was successfully treated after stent implantation without use of RA (white arrow).

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  Fig. 5. ROC curve analysis of various parameters for identifying calcified lesions treated with RA. Calcification remodeling index showing largest AUC and best diagnostic performance over other parameters. AUC = area under curve, CI = confidence interval, ROC = receiver operating characteristic. Calcification remodeling index showing largest AUC and best diagnostic performance over other parameters.