Vulnerable plaque: scope of the problem

Diagnostic and Prognostic Blood Biomarkers in Transient Ischemic Attack and Minor Ischemic Stroke: An Up-To-Date Narrative Review

INTRODUCTION

Early diagnosis and correct risk stratification in patients with transient ischemic attack (TIA) and minor ischemic stroke (MIS) is crucial for the high rate of subsequent disabling stroke. Although highly improved, diagnosis and prognostication of TIA/MIS patients remain still based on clinical and neuroimaging findings, with some inter-rater variability even among trained neurologists.

OBJECTIVES

To provide an up-to-date overview of diagnostic and prognostic blood biomarkers in TIA and MIS patients.

MATERIAL AND METHODS

We performed a bibliographic search on PubMed database with last access on July 10^th 2021. More than 680 articles were screened and we finally included only primary studies on blood biomarkers.

RESULTS

In a narrative fashion, we discussed about blood biomarkers investigated in TIA/MIS patients, including inflammatory, thrombosis, neuronal injury and cardiac analytes, antibodies and microRNAs. Other soluble molecules have been demonstrated to predict the risk of recurrent cerebrovascular events or treatment response in these patients. A rapid point of care assay, combining the determination of different biomarkers, has been developed to improve triage recognition of acute cerebrovascular accidents.

CONCLUSIONS

The implementation of blood biomarkers in the clinical management of TIA/MIS could ameliorate urgent identification, risk stratification and individual treatment choice. Large prospective and longitudinal studies, adopting standardized sampling and analytic procedures, are needed to clarify blood biomarkers kinetic and their relationship with TIA and minor stroke etiology.

Angiographic characteristics of coronary arterial segments progressing to myocardial infarction in patients with and without chronic kidney disease

BACKGROUND

Individuals with chronic kidney disease (CKD) have high rates of myocardial infarction (MI), but whether the nature of coronary lesions susceptible to plaque rupture is altered and whether the high rate of MI is related to a greater burden of atherosclerotic lesions in individuals with CKD is uncertain.

METHODS

We used quantitative coronary angiography to assess atherosclerotic plaque location and characteristics at baseline and at the time of MI in 62 patients with and without CKD. Univariate and multivariable conditional logistic regression models were used to assess whether the association between pre-MI angiographic findings and MI differs in individuals with and without CKD.

RESULTS

The risk of MI rose as the distance from the coronary ostium decreased both in patients with CKD (odds ratio per 10 mm 0.92 [95 % CI 0.87-0.99]) and in those without CKD (odds ratio 0.83 [95 % CI 0.75-0.93]). Although tighter degrees of coronary stenosis were associated with increased risks of MI in patients with and without CKD, the majority of MIs (70.9 % in patients with CKD and 89.5 % in those without CKD) occurred in segments with <50 % diameter stenosis at baseline.

CONCLUSIONS

The characteristics of lesions progressing to MI are similar in individuals with and without CKD and the majority of events occur in areas with <50 % stenosis at baseline. Given the high burden of non-stenotic lesions in patients with CKD, an interventional strategy aimed solely at sites with high-grade stenosis is unlikely to markedly reduce the risk of MI in patients with CKD.

Recent developments with lipoprotein-associated phospholipase A2 inhibitors

Lipoprotein-associated phospholipase A(2) (Lp-PLA(2)) is a calcium-independent phospholipase A(2) enzyme secreted by leukocytes and associated with circulating low-density lipoprotein and macrophages in atherosclerotic plaques. Until recently, the biological role of Lp-PLA(2) in atherosclerosis was controversial, but now the preponderance of evidence demonstrates a proatherogenic role of this enzyme. Lp-PLA(2) generates two proinflammatory mediators, lysophosphatidylcholine and oxidized nonesterified fatty acids, which play a major role in the development of atherosclerotic lesions and formation of a necrotic core, leading to more vulnerable plaques. These findings have opened the door to a potential novel therapeutic target, selective inhibition of Lp-LPA(2). Recently, both animal models and human studies have shown that selective inhibition of Lp-PLA(2) reduces plasma Lp-PLA(2) activity, plaque area, and necrotic core area. This article reviews the most recent developments with Lp-PLA(2) inhibitors.