Coronary Plaque Stress Mapping for Event Risk: Advances in Clinical Assessment and Prognostication

Abstract

Coronary plaque stress mapping has emerged as a pivotal technique in the assessment of atherosclerotic plaque vulnerability and the prediction of acute coronary events. By integrating advanced imaging modalities with biomechanical modeling, plaque stress mapping offers a mechanistic evaluation of plaque behavior beyond traditional anatomical assessments. This article systematically reviews the evidence, clinical applications, and future prospects of coronary plaque stress mapping in the context of risk stratification for cardiovascular events. Emphasis is placed on the underlying pathophysiology, epidemiological burden, diagnostic strategies, and the latest guideline recommendations, providing a comprehensive resource for clinicians and researchers involved in cardiovascular care.

Introduction

Despite advances in cardiovascular prevention and intervention, acute coronary syndromes (ACS) continue to be a leading cause of morbidity and mortality globally. Traditional risk assessment tools, including angiographic stenosis severity and plaque composition, have limitations in predicting which plaques are likely to rupture and cause clinical events. Coronary plaque stress mapping, which evaluates the distribution and magnitude of biomechanical stresses within atherosclerotic lesions, has garnered considerable attention as a means to enhance risk prediction and guide patient management. This review explores the scientific basis, clinical relevance, and practical implications of plaque stress mapping in contemporary cardiology practice.

Epidemiology / Disease Burden

Cardiovascular disease (CVD) remains the foremost cause of death worldwide, with coronary artery disease (CAD) accounting for a significant proportion of these fatalities. According to the World Health Organization, CAD is responsible for an estimated 9 million deaths annually. While primary and secondary prevention strategies have reduced overall event rates, a substantial residual risk persists, particularly among patients with subclinical or non-obstructive disease. Studies indicate that the majority of myocardial infarctions arise from the rupture of plaques previously considered non-significant by angiographic criteria. This recognition underscores the need for more sensitive and specific tools, such as plaque stress mapping, to identify high-risk lesions before clinical events occur.

Pathophysiology

The pathogenesis of acute coronary syndromes is intimately linked to the biomechanical properties of atherosclerotic plaques. Plaque rupture is primarily a mechanical failure, occurring when local wall stresses exceed the structural integrity of the fibrous cap. Factors such as cap thickness, lipid-rich necrotic core size, inflammation, and microcalcification influence local stress concentrations. Plaque stress mapping, leveraging computational fluid dynamics and finite element analysis, quantifies these biomechanical forces in vivo. High stress regions, particularly at the shoulders of thin-cap fibroatheromas, have been correlated with subsequent rupture and thrombosis. This mechanistic insight distinguishes stress mapping from conventional imaging, which may overlook plaques at imminent risk.

Risk Factors

Traditional risk factors for CAD such as hypertension, hyperlipidemia, diabetes mellitus, smoking, and family history contribute to the development and progression of atherosclerosis. However, their predictive power for individual plaque rupture events is limited. Local factors, including plaque morphology, cap thickness, and inflammatory cell infiltration, play a critical role in determining biomechanical vulnerability. Advanced imaging-based stress mapping allows for the identification of plaques with disproportionately high mechanical stress, even in the absence of severe luminal stenosis, thus refining risk stratification beyond systemic clinical parameters.

Clinical Features

Plaque rupture and subsequent thrombus formation are the primary mechanisms underlying most cases of unstable angina, non-ST elevation myocardial infarction (NSTEMI), and ST elevation myocardial infarction (STEMI). Clinically, these events manifest as acute chest pain, hemodynamic instability, and electrocardiographic changes. Notably, many culprit plaques responsible for ACS are angiographically mild to moderate in severity prior to rupture. This clinical paradox further emphasizes the need for accurate lesion-specific risk assessment through techniques such as coronary plaque stress mapping, which can identify lesions prone to rupture before symptom onset.

Diagnosis

Diagnostic assessment of plaque vulnerability has traditionally relied on invasive coronary angiography and, more recently, intravascular ultrasound (IVUS), optical coherence tomography (OCT), and coronary computed tomography angiography (CCTA). While these modalities provide valuable structural information, they often fail to capture the biomechanical environment within plaques. Plaque stress mapping utilizes high-resolution imaging data integrated with computational modeling to calculate peak cap stress, wall shear stress, and other biomechanical indices. These parameters have demonstrated strong associations with histologically defined vulnerable plaques and, in longitudinal studies, with future coronary events. Incorporation of stress mapping into diagnostic workflows has the potential to enhance the predictive accuracy for adverse events beyond traditional imaging alone.

Treatment & Management

The identification of high-risk plaques through stress mapping has significant implications for patient management. Patients with plaques demonstrating elevated mechanical stress may benefit from intensified medical therapy, including aggressive lipid-lowering agents, anti-inflammatory therapies, and antithrombotic medications. In select cases, pre-emptive percutaneous coronary intervention (PCI) may be considered for non-obstructive but high-risk lesions, although this approach remains investigational. Importantly, stress mapping can guide surveillance strategies, allowing for targeted monitoring of lesions most likely to progress or rupture. The integration of biomechanical data into clinical decision-making represents an evolving paradigm in personalized cardiovascular care.

Recent Advances / Emerging Therapies

Recent advancements in imaging technology and computational modeling have expanded the utility of plaque stress mapping. Developments include artificial intelligence–driven segmentation of imaging data, real-time computation of stress indices, and integration with multi-omics biomarkers for comprehensive risk profiling. Emerging therapies targeting the biomechanical and inflammatory milieu within plaques, such as novel anti-cytokine agents and nanoparticle-based drug delivery systems, are currently under investigation. Early-phase clinical trials are evaluating the impact of stress-guided therapy on event rates, with promising preliminary results. Continued innovation is expected to further refine the prognostic and therapeutic value of plaque stress mapping in clinical practice.

Guideline Recommendations

Current international guidelines emphasize the importance of risk stratification in coronary artery disease but have yet to formally endorse plaque stress mapping for routine clinical use, primarily due to the need for larger prospective outcome studies. However, the growing body of evidence supporting the prognostic utility of biomechanical assessment has prompted recommendations for its use in research and specialized clinical settings. The European Society of Cardiology and American College of Cardiology have recognized the potential of advanced imaging and computational modeling to enhance risk prediction, with ongoing guideline updates anticipated as further evidence emerges.

Conclusion

Coronary plaque stress mapping represents a significant advancement in the mechanistic understanding and clinical assessment of atherosclerotic disease. By providing lesion-specific risk profiles based on biomechanical vulnerability, stress mapping addresses critical gaps in current risk stratification paradigms and holds promise for guiding personalized therapeutic strategies. Ongoing research and technological development are expected to further establish its role in clinical practice, with the ultimate goal of reducing the burden of acute coronary events through targeted prevention and early intervention.