Serial Baseline, 12-, 24-, and 60-Month Optical Coherence Tomography Evaluation of ST Segment Elevation Myocardial Infarction Patients Treated with Absorb Bioresorbable Vascular Scaffold.

ABSTRACT

Data on long-term neointimal healing and neoatherosclerosis progression after primary percutaneous coronary intervention (PCI) with implantation of everolimus-eluting bioresorbable vascular scaffold (BVS) (ABSORB BVS 1.0, Abbott Vascular) are limited. The mechanisms underlying very late scaffold failure remain to be further elucidated. This study sought to assess healing pattern and presence of neoatherosclerosis. This was a single-center, prospective, longitudinal study with serial optical coherence tomography (OCT) assessment at baseline, 12, 24 and 60 months after PCI performed in 12 patients presenting with ST-segment elevation myocardial infarction (STEMI). The median follow-up was 59 months. The diameter stenosis increased from 7.11 ± 4.99% at 1-year to 21.00 ± 11.31% at 5 years, (p = 0.03), whereas minimum lumen diameter remained stable throughout the follow-up period, as assessed by angiography. Minimum and mean lumen area declined over the 5-year follow-up by 1.00 ± 1.57 mm2 and 1.75 ± 0.87 mm2, respectively; a significant decrease in minimum and mean lumen area in the first two years, was followed by stable luminal dimensions between 2 and 5 years of follow-up. The lumen eccentricity (0.85 ± 0.03) and asymmetry (0.43 ± 0.10) indexes showed no change over 60-month follow-up. The incidence of atherosclerosis was high both in the in-scaffold (IS) and out-scaffold (OS) regions consisting of calcifications (IS = 100%, OS = 92%, p = 0.99), macrophages (IS = 92% and OS = 67%, p = 0.31), neovascularization (IS = 75%, OS = 50%, p = 0.40). In conclusion, serial OCT imaging up to 5 years after implantation of BVS in STEMI indicated complete scaffold resorption, stable lumen area following period of neointima growth in the first two years after PCI and high incidence of neoatherosclerosis.