Assessment of atherosclerotic plaque morphology using contrast-enhanced ultrasound and its impact on primary cardiovascular events following simultaneous carotid endarterectomy and coronary artery bypass grafting

Abstract

Objective

The incidence of stroke after on-pump cardiac surgery during the perioperative period can affect up to 2% of patients, and is frequently linked to carotid artery disease. Notably, in patients with significant unilateral carotid artery stenosis of 80%–99%, the risk of stroke reaches 4%. Among individuals undergoing coronary artery bypass grafting (CABG), 3% to 10% exhibit significant carotid artery stenosis. To mitigate the risk of stroke and mortality, patients can undergo either simultaneous or staged carotid endarterectomy and CABG. The aim of this study was to assess whether early postoperative complications, including stroke, following simultaneous CABG/CAE procedures, correlate with morphological attributes of carotid plaque, assessed via contrast-enhanced ultrasound.

Methods

A single centre retrospective analysis was performed including 62 patients who underwent simultaneous CABG/CEA between 2019 and 2022. Our study excluded patients who underwent staged carotid endarterectomy and CABG procedures, off-pump CABG, or those necessitating urgent CABG. Our analysis focused on patients meeting elective CABG criteria, diagnosed with symptomatic triple-vessel or left main trunk coronary artery disease (CAD), alongside asymptomatic carotid stenosis (a. carotis internae) exceeding 70% or symptomatic ipsilateral carotid stenosis surpassing 50%. The extent of contralateral carotid artery stenosis was not taken into account. Prior to the CEA/CABG procedure, each patient underwent contrast-enhanced ultrasound to assess atherosclerotic lesions, which were classified using Nakamura et al.’s classification. Among the patients, 37.1% exhibited no neovascularisation within the atherosclerotic plaque, 56.5% showed insignificant neovascularisation, and 6.5% displayed notable neovascularization within the plaque. Our study aimed to establish a connection between the degree of plaque vascularisation identified through contrast-enhanced ultrasound and subsequent postoperative complications.

Results

Upon evaluating postoperative complications occurring within 30 days after the surgery and the plaque morphology identified through contrast-enhanced ultrasound, a statistically significant correlation was observed between a higher grade of plaque vascularisation and the occurrence of ischaemic stroke (r = 0.329, p = .008). Monte Carlo calculations of the Chi-square test indicated a significant association between a higher grade of plaque vascularisation and the presence of peripheral artery disease (χ2 = 15.175, lls = 2, p = .003).

Conclusion

Within 30 days of surgery, a significant correlation exists between the occurrence of ischaemic stroke following carotid endarterectomy subsequent to CABG and the presence of a higher grade plaque vascularisation as identified by contrast-enhanced ultrasound.