Modifications of coronary plaque phenotype on lipid-lowering therapies and risk of cardiovascular events: a systematic review and meta-regression analysis

Background and aims: The specific relationship between changes in coronary plaque phenotype by optical coherence tomography (OCT) and decrease in major adverse cardiovascular events (MACE) among patients receiving lipid-lowering therapies (LLTs) is unknown. Aim was to quantify the relationship between LLTs-related improvement of coronary plaque phenotype (e.g. coronary plaque stabilization, as assessed by OCT) and MACE occurrence. Methods: A comprehensive, systematic search of publications in PubMed, Embase, Cochrane Central Register of Controlled Trials and Web of Science was performed to identify eligible studies. A total of 8 studies (5 randomized and 3 observational) on LLTs reporting mean maximum lipid arc (LA) and mean minimum fibrous cap thickness (FCT) at baseline and during follow-up, as assessed by OCT, and incidence of MACE were selected, encompassing a total of 652 patients. Results: Mean follow-up duration was 8.6 months. Meta-regression analysis revealed a significant direct relationship between absolute change in LA and MACE occurrence (coefficient 0.055, I2 0 %, p < 0.001), with each 10° decrease in LA being related to a 39 % MACE reduction (OR 0.61, 95 % CI 0.44–0.77). The indirect relationship between absolute change in FCT and risk of MACE was not significant (coefficient −0.011, I2 59 %, p = 0.136). Conclusions: This analysis quantifies the potential of LLT-related modifications of coronary plaque phenotype in terms of LA decrease for reducing the risk of MACE within the first year of treatment. These findings suggest that LA changes might be a surrogate for changes in MACE.