CASE 03: A VULNERABLE MID-RCA LESION

This case demonstrates how OCT imaging, complemented by OCT-FFR and Index of Plaque Attenuation (IPA) analysis, revealed vulnerable plaque features and thrombus beyond angiography, informed stent landing-zone planning, and assessed the anatomical and image-derived physiological results of PCI.

A 50-year-old man with an eight-year history of diabetes and long-term smoking presented with progressive exertional chest tightness and markedly reduced exercise tolerance, with symptoms after walking approximately 100 meters.

Coronary angiography revealed 80–90% stenosis in the mid-right coronary artery (RCA), with preserved TIMI 3 flow. Following predilatation with a 2.5 × 20 mm semi-compliant balloon, OCT was performed before stent implantation.

OCT demonstrated predominantly lipid-rich plaque, intraluminal thrombus, and vulnerable plaque features, including physician-identified thin-cap fibroatheroma (TCFA). No significant calcification was observed.

Additional IPA assessment showed a maximum IPA₄mm value of 459, with color-coded regions along the diseased segment, providing complementary information for plaque assessment and landing-zone planning.

OCT enabled assessment of longitudinal plaque distribution and proximal and distal reference-vessel anatomy. These findings helped guide landing-zone selection, aiming for adequate lesion coverage while minimizing unfavorable plaque characteristics at the stent edges.

A 3.25 × 30 mm stent was implanted in the mid-RCA. Final angiography showed no significant residual stenosis and preserved TIMI 3 flow.

Final OCT allowed quantitative assessment of stent expansion and apposition and evaluation of the stent edges beyond the angiographic appearance.

The final assessment demonstrated favorable stent expansion and complete apposition, while OCT-FFR indicated an improvement in the image-derived physiological estimate following revascularization.