Chronic total occlusion is associated with a higher incidence of malapposition and uncovered stent struts: OCT findings at 6 months following DES implantation.

Objectives: To compare stent coverage and malapposition in patients with chronic total occlusion (CTO) lesions and non-CTO lesions (including lipid-rich plaque [LRP] and non-lipid-rich plaque [non-LRP]) after drug-eluting stent (DES) implantation by optical coherence tomography (OCT).

Background: Different initial lesion characteristics may be related to heterogeneous vessel responses after DES implantation. However, the vessel response in patients with CTO and non-CTO lesions after stenting is unclear. Methods We retrospectively enrolled 64 patients with 68 target lesions. All of the patients underwent OCT imaging immediate after stenting and 6 months after stenting. LRP was defined as the plaque with lipid content in ≥2 quadrants. Non-LRP consisted of fibrous, fibrocalcific plaque, and lipid plaque with less than 2 quadrants lipid content.

Results: The malapposition (3.0%, 2.6% vs. 0.6%, P = 0.022), tissue protrusion (15.0% vs. 11.0% vs. 6.4%, P < 0.001), and intrastent thrombus (3.8% vs. 2.4% vs. 1.1%, P = 0.012) were more frequent in the CTO and LRP groups. At 6-month follow-up, malapposition (5.0% vs. 1.0% and 0.4%, P = 0.002) and cross sections with uncovered struts (23.4% vs. 8.2% and 6.6%, P < 0.001) were most frequently observed in the CTO group. Although the incidence of stent thrombosis was non-significantly higher in the CTO group than the other two groups, no events were observed in patients with CTO.

Conclusions: Patients with CTO lesions showed unfavorable responses to DES in the acute phase as well as at the 6-month follow-up, indicating the important pathological link between the original lesion morphology underneath the stents and heterogeneous artery healing. © 2017 Wiley Periodicals, Inc.