Plaque erosion delays vascular healing after drug eluting stent implantation in patients with acute coronary syndrome: An In Vivo Optical Coherence Tomography Study.

OBJECTIVES: To compare vascular healing after drug-eluting stent (DES) implantation between plaque rupture (PR) and plaque erosion (PE). BACKGROUND: Vascular response after stent implantation in patients with PR has been extensively studied. Little is known about vascular healing after stent implantation in PE. METHODS: Sixty-five ACS patients who received optical coherence tomography (OCT) imaging of the culprit lesions both before and after stent implantation at baseline as well as at 6 months were included in this study. Patients were divided into two groups: PR (n = 19) and PE (n = 24). Prestent thrombus burden and poststent intrastent structure (ISS) volume were analyzed during the index procedure. The ratio of uncovered to total stent struts per cross-section score (RUTTS) and neointimal thickness and area were measured at follow-up. RESULTS: OCT imaging showed that compared with PR, PE showed a significantly lower prestent thrombus score (34.2 ± 19.2 vs. 68.6 ± 44.2, P = 0.009) at baseline and a smaller poststent ISS volume (0.7 ± 0.9 mm3 vs. 2.1 ± 1.9 mm3 , P = 0.019). At the 6-month follow-up, PE showed a higher incidence of RUTTS >0.3 (12.2 ± 14.4 vs. 2.0 ± 4.5%, P = 0.003), thinner neointimal thickness (0.05 ± 0.02 mm vs. 0.12 ± 0.08 mm, P = 0.002), and smaller neointimal area (0.5 ± 0.2 vs. 1.2 ± 0.9 mm2 , P = 0.004) compared with PR. In a multivariate logistic model, PE was identified as an independent predictor for RUTTS >0.3. CONCLUSIONS: PE was associated with less favorable healing following DES implantation when compared to PR at 6 months, indicating longer dual-antiplatelet therapy may be necessary for patients with PE. © 2017 Wiley Periodicals, Inc.

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.

Management and Outcome of Patients With Acute Coronary Syndrome Caused by Plaque Rupture Versus Plaque Erosion: An Intravascular Optical Coherence Tomography Study.

BACKGROUND: Plaque rupture and erosion are the 2 most common mechanisms for acute coronary syndromes. However, the outcome of these 2 distinct pathologies in patients with acute coronary syndromes has never been studied. METHODS AND RESULTS: We retrospectively studied 141 patients with acute coronary syndromes who underwent optical coherence tomography (OCT) imaging of the culprit lesion prior to stenting from the Massachusetts General Hospital OCT Registry. Management (stent versus no stent), poststent OCT findings, and outcomes were compared. Among the 141 culprit lesions, rupture was found in 79 (56%) patients and erosion in 62 (44%). Stent implantation was performed in 77 (97.5%) patients with rupture versus 49 (79.0%) in those with erosion (P<0.001). Immediately after percutaneous coronary intervention, OCT showed a higher incidence of malapposition (37.5% versus 7.3%, P<0.001), thrombus (59.4% versus 14.6%, P<0.001), and protrusion (93.8% versus 73.2%, P=0.008) in the rupture group compared with the erosion group. Plaque rupture was associated with a higher incidence of no reflow or slow flow and distal embolization. Although cardiac event rates were comparable between the two groups at the 1-year follow-up, none of the erosion patients who were treated conservatively without stenting had adverse cardiac events. CONCLUSIONS: Unfavorable poststent OCT findings were more frequent in rupture patients compared with erosion patients. A subset of erosion patients who were treated conservatively without stenting remained free of adverse cardiac events for up to 1 year.