Thin cap fibroatheroma and plaque rupture is associated with carotid thermal heterogeneity in patients presenting with acute myocardial infarction
Authors: Bounas P , Karanasos A , Synetos A , Papanikolaou A , Latsios G , Drakopoulou M , Trantalis G , Olympios C , Tousoulis D , Toutouzas K 
Published: November 2020

Abstract

Microwave radiometry (MWR) has been applied successfully in the evaluation of carotid atherosclerosis, measuring reliably temperature heterogeneity of atherosclerotic plaques. Recent studies have shown an association between increased carotid temperature heterogeneity (ΔT) detected by MWR and cardiovascular events. Vulnerable plaques of the coronary arteries, share common characteristics such as the thin cap fibrous cap, that make the prone to rupture in the presence of stimulus such as shear stress or inflammation. Optical coherence tomography (OCT) is an imaging method, by which the fibrous cap and the presence of plaque rupture can be accurately in vivo visualized.

Purpose
To evaluate the impact of carotid temperature heterogeneity on the culprit plaque morphology on patients presenting with acute myocardial infarction.

Method
A total of 37 patients undergoing percutaneous coronary intervention (PCI) for an acute myocardial infarction who had an identifiable de novo culprit lesion in a native coronary artery, were enrolled in this study. All patients underwent PCI and Optical Coherence Study (OCT) within 12 hours since symptom onset. The OCT study was performed according to the standard techniques and acquired images were analyzed by 2 independent investigators., After the completion of the PCI all patients underwent MWR of both carotid arteries and ΔT was defined as maximal temperature detected along each carotid artery minus minimum.

Results
Thirty four patients with acute myocardial infarction 21 with STEMI (61.76%) and 13 (38.23%) with NSTEMI were included in the study. Thin cap fibroatheroma (TCFA) was present in 31 patients (91.1%), while all ruptured plaques had a TCFA compared to 11 TCFA (78.57%) observed in plaques that had no rupture (p=0.03). HsCRP was significantly increased in ruptured plaques compared to non ruptured ones (14.41±4.02 versus 9.9±2.5, p&lt;0.005). Mean ΔT was significantly increased in ruptured plaques compared to no ruptured ones (1.01±0.31 versus 0.51±0.14°C, p&lt;0.005), as well as in plaques with TCFA compared to those without a TCFA (0.82±0.37 versus 0.60±0.05°C, p=0.001). In the multivariate analysis DM, hsCRP, and ΔT were entered from which DM (OR 4.12; 95% CI 0.77–22.07; P=0.07) and ΔTau ((OR for 0.1°C increase 1.43; 95% CI 1.03–1.98; P=0.03) remained in the final model, with ΔT being the only variable independently associated with the presence of TCFA. Similarly regarding plaque rupture, STEMI, hsCRP, and ΔT were entered in the multivariate analysis from which hsCRP (OR 1.51; 95% CI 0.99–2.28; P=0.051) and ΔTau ((OR for 0.1°C increase 3.40; 95% CI 1.29–8.96; P=0.013) remained in the final model, with ΔT being the only variable independently associated with the presence of rupture.

Conclusions
Carotid thermal heterogeneity is associated with TCFA and plaque rupture in patients with acute myocardial infarction.

Funding Acknowledgement
Type of funding source: None