103 Coronary plaque healing and diabetes: insights from optical coherence tomography imaging

Abstract

Aims Atherosclerotic plaque healing is a dynamic process developing after plaque rupture or erosion, which aims to prevent lasting occlusive thrombus formation and to promote plaque repair. We hypothesized that diabetes mellitus, one of the major conventional cardiovascular risk factors, may influence the healing capacity after plaque destabilization. Methods and results In this single-centre observational cohort study, patients with acute coronary syndrome (ACS) or chronic coronary syndrome (CCS) who underwent optical coherence tomography (OCT) imaging at Fondazione Policlinico A. Gemelli–IRCCS, Rome, were included. Patients were divided into two groups (i.e. diabetes vs. no diabetes), and stratified based on diabetes medications (i.e. insulin, vs. oral antidiabetic drugs). OCT analysis of non-culprit coronary segments was performed. 105 patients were included (44 diabetes, 61 no diabetes). Prevalence of HCPs was not significantly different between patients with and without diabetes (3.6% vs. 3.8%, P = 0.854). However, patients with diabetes on insulin showed a lower prevalence of HCPs both at patient-based (7.1% vs. 26.4%, P = 0.116) and at segment-based analysis (1.2% vs. 4.2%, P = 0.020). When comparing HbA1c levels based on the presence or absence of healed plaque at the non-culprit lesions, patients with healed plaque showed significantly lower levels of HbA1c compared to patients without healed plaques (43.5 ± 12.1% vs. 61.2 ± 10.4%, P < 0.001). At segment-based analysis, normal vessel structure, pathological intimal thickening (PIT), and spotty calcifications were significantly less prevalent in diabetic patients (2.1% vs. 5.1%, P = 0.001; 7.2% vs. 9.5%, P = 0.05; 9.9% vs. 13.6%, P = 0.02, respectively), whereas neovascularization was significantly higher (19.2% vs. 15.6%, P = 0.035). Conclusions Patients with diabetes have a distinct coronary non-culprit plaque phenotype. Healing capacity may be impaired in patients with advanced diabetes on insulin therapy and in those with a suboptimal control of the disease. Further prospective, larger scale studies are warranted to confirm these findings.