Abstract 9862: Correlation of Lipoprotein(a) and Plaque Morphology in Very Young Acute Coronary Syndrome Patients Using Optical Coherence Tomography

Abstract

Background: Levels of lipoprotein (Lp) (a) are a useful marker for risk stratification of cardiovascular diseases. This genetic biomarker is suggestive of patient predisposition to an acute coronary event. Its correlation with the plaque morphology is yet to be explored with optical coherence tomography (OCT). Aim: To study the correlation of Lp(a) levels and plaque morphology in very young (<35 years) patients presenting with acute coronary syndrome(ACS). Methods: A prospective, single-centre, observational study was conducted at a tertiary-care centre. Very young patients with acute coronary syndrome and fit for OCT guided invasive coronary angiography were included. Lp(a) levels were compared between healthy controls and these very young ACS patients. Correlation of Lp(a) levels and plaque characteristics in very young ACS patients was done using OCT imaging. Results: A total of 80 subjects were enrolled in the study. Out of these 40 were very young ACS and 40 were age matched healthy controls. Mean levels of Lp(a) were 28.10±13.96 nmol/l and 61.20±55.88 nmol/l in healthy controls and very young patients with ACS respectively (p=0.022). In very young patients, plaque rupture and erosion were the mechanism of acute coronary syndrome in 67.5% and 32.5% patients, respectively. Among very young ACS patients, those with Lp(a) levels <75 nmol/l had a mean thin cap fibroatheroma thickness of 96.89±65.52 μm and those with Lp(a) levels ≥75 nmol/l had a mean thin cap fibroatheroma thickness of 67.85±53.80 μm (p=0.158). Conclusion: It was revealed that patients with higher Lp(a) levels had lesser thickness of fibrous cap on OCT imaging compared with lower levels of Lp(a). Lp(a) levels were independently associated with ACS in very young (<35 years) patients, with plaque rupture being the commonest mechanism. Hence, we conclude that higher Lp(a) levels predispose to ACS at a very young age associated with lowering of fibrous cap thickness.