The association between plaque characterization by CT angiography and post-procedural myocardial infarction in patients with elective stent implantation.

OBJECTIVES

This study sought to evaluate the association between volumetric characterization of target lesions by multidetector computed tomography (MDCT) angiography and the risk of post-procedural myocardial injury after elective stent implantation.

BACKGROUND

Previous reports have shown that plaque characterization of the target lesion may provide useful information for stratifying the risk of coronary stenting.

METHODS

A total of 189 consecutive patients were enrolled; they underwent elective stent implantation after volumetric plaque analysis with 64-slice MDCT. Each plaque component and lumen (filled with dye) was defined as follows: 1) low-attenuation plaque (LAP) (<50 HU); 2) moderate-attenuation plaque (MAP) (50 to 150 HU); 3) lumen (151 to 500 HU); and 4) high-attenuation plaque (HAP) (>500 HU). The volume of each plaque component in the target lesion was calculated using Color Code Plaque. Post-procedural creatine kinase-MB isoform and troponin-T (TnT) at 18 h after percutaneous coronary intervention were also evaluated.

RESULTS

The volumes of LAP (87.9+/-94.8 mm3 vs. 47.4+/-43.7 mm3, p<0.01) and MAP (111.6+/-77.5 mm3 vs. 89.8+/-67.1 mm3, p<0.05) were larger in patients with post-procedural myocardial injury (defined as positive TnT) than in those with negative TnT. The volumes of LAP and MAP and fraction of LAP in total plaque (LAP volume/total plaque volume) correlated with biomarkers; the MAP fraction was inversely correlated with biomarkers. The volume of LAP was an independent predictor of positive TnT after adjusting for patient background, conventional IVUS parameters, and procedural factors.

CONCLUSIONS

Post-procedural myocardial injury was associated with the volume and fraction of LAP as detected by MDCT. The volume of LAP was an independent predictor of positive TnT. Plaque analysis by MDCT would be a useful method for predicting post-procedural myocardial injury after percutaneous coronary intervention.