Comparison of Intravascular Imaging and Quantitative Coronary Angiography to Evaluate Neointimal Proliferation after Complex Lesion Stenting

Unlike quantitative coronary angiography (QCA), intravascular imaging methods allow direct visualisation of the arterial wall. Our goal was to determine several intravascular ultrasound (IVUS) and optical coherence tomography (OCT) parameters of neointimal proliferation and stent endothelisation after complex lesion intervention compared to QCA. We examined 261 patients who had underwent percutaneous intervention with bare metal (BMS) or drug eluting stent (DES) implantation for complex coronary lesions and had IVUS or OCT images at six-month follow-up. Percent diameter stenosis (QCA) was 25.2 ± 16.0 in BMS vs 21.7 ± 17.4 in DES (P < 0.05). Percent neointimal volume obstruction (IVUS) was 19.5 ± 14.4 in BMS vs. 5.8 ± 7.7 in DES (P < 0.001). A moderate correlation was observed between QCA and IVUS with an r value of 0.384 overall, 0.472 for BMS and 0.416 for DES (P < 0.001 for all). In patients with chronic total occlusions (n = 161) QCA was similar in BMS and DES patients (P > 0.05) while IVUS showed less neointima in DES (P < 0.05). Total number of uncovered stent struts per OCT image was 0.4 ± 0.8 while per IVUS image 1.2 ± 1.5 (P < 0.001). In conclusion, angiographic indexes correlate with volumetric intravascular parameters. Although IVUS was more sensitive than QCA to assess neointimal proliferation, the assessment of stent endothelisation was more precise using OCT.