Stent-Edge Hinge Movement in a Calcified Lesion Is Associated With Increased Prevalence of a Calcified Nodule at Follow-Up

BACKGROUND: Coronary stenting alters vessel dynamics, displacing hinge movement closer to stent edges. We aimed to investigate whether calcified nodules (CNs) are more frequent at stent edges associated with calcium. METHODS: In vessels with previously implanted stents evaluated by optical coherence tomography, 4 different calcified lesions were studied: stent-edge calcified lesions with or without a CN, and unstented native calcified lesions with or without a CN. RESULTS: In 801 patients, 989 stent-edge calcified lesions and 354 unstented native calcified lesions were identified. Stent-edge calcified lesions exhibited a higher prevalence of CNs versus native calcified lesions (15.7% versus 5.1%; P <0.001) and were observed in locations (mid left anterior descending artery, mid left circumflex, or branches) where no unstented native vessel CNs were seen. Stent-edge (versus native vessel) location (odds ratio [OR], 4.58 [95% CI, 2.23–9.43]) predicted the presence of a CN. Correspondingly, greater angiographic (systole-diastole) ∆angle at the stent edge or unstented lesion (per 10°, OR, 2.27 [95% CI, 1.43–3.60]) and greater calcium burden: calcium length (per 10 mm, OR, 4.04 [95% CI, 2.36–6.92]), maximum calcium arc (per 90°, OR, 1.65 [95% CI, 1.25–2.17]), and maximum calcium thickness (per 0.1 mm, OR, 1.25 [95% CI, 1.15–1.36]) were associated with the presence of a CN. Stent-edge CNs were associated with a higher rate of stent-edge calcified lesion-related major adverse cardiac events (a composite of cardiac death, target vessel-related myocardial infarction, clinically driven target lesion revascularization, or definite/probable stent thrombosis) compared with stent edges without a CN (15.9% versus 6.5%; P =0.01), mainly driven by target lesion revascularization. CONCLUSIONS: Stent-edge calcium may predispose to the development of a CN. Stent-edge CNs were associated with a higher major adverse cardiac events rate than stent edges without a CN, whether treated or untreated.