Abstract 4365: Delayed Strut Coverage in a Diabetic Population Treated With Paclitaxel Eluting and Bare Metal Stents: Sub-analysis of the Horizons-OCT Trial
Background: Diabetes Mellitus (DM) is a well known risk factor for higher major adverse cardiovascular events after stent implantation. Delayed healing after drug eluting stent implantation in acute myocardial infarction (AMI) has been reported. We aim to evaluate vascular healing post stent implantation by optical coherence tomography (OCT) in a DM population who suffered AMI.
Methods: The Horizons-OCT trial was a single-center, prospective, randomized, controlled substudy to evaluate long-term strut coverage of paclitaxel-eluting stents compared with bare metal stents in AMI at a 3:1 ratio. A total of 217 stent segments including 46 overlapping (OLP) segments were analyzed in 118 patients. OCT volumetric and strut-level analyses were performed by an independent core laboratory. Endpoints were neointimal hyperplasia (NIH) volume, degree of strut coverage and presence of abnormal intraluminal tissue (AIT) at 13 months. Uncovered or malapposed struts, defined quantitatively were considered vulnerable struts (VS).
Results: Incidence of DM was 18/118 (15.3%), and a total of 35 stent segments in the DM population were compared with 182 stent segments in non-DM patients. OLP segments were 8 and 38 respectively. Patient characteristics were similar except for higher incidence of obesity (p=0.018) and hypertension (p=0.007) in the DM group. At follow-up, NIH volume was similar between the 2 groups. Despite similar amount of NIH, DM had higher incidence of VS as compared to non-DM patients, which was more pronounced at OLP segments. Further, DM had more consecutive frames, thus longer distances of identified VS. AIT was observed exclusively in DM OLP segments.
Conclusion: OCT suggested delayed vascular healing in DM population who received stent for AMI treatment compared with non-DM, in spite of similar NIH. DM population with OLP stent segments were particularly susceptible to malapposition and presence of abnormal intraluminal tissue.