Coronary Shear Stress Profiles as Predictors of Future Cardiovascular Events

Abstract

Coronary shear stress, a biomechanical force generated by blood flow along the endothelial surface, is increasingly recognized as a pivotal predictor of future cardiovascular events. Recent advances in imaging and computational modeling have enabled more precise quantification of shear stress profiles within coronary arteries, shedding light on the mechanistic relationship between hemodynamic forces, endothelial dysfunction, and atherogenesis. This review synthesizes current evidence regarding the prognostic value of coronary shear stress, its integration with traditional risk factors, and its potential to refine cardiovascular risk stratification. Emphasis is placed on clinical implications, emerging diagnostic modalities, and the evolving role of shear stress assessment in personalized cardiovascular medicine.

Introduction

Cardiovascular diseases (CVD), particularly those arising from coronary artery pathology, remain the leading cause of morbidity and mortality worldwide. Traditional risk stratification relies on clinical, biochemical, and imaging parameters; however, these often fail to capture the dynamic interplay between blood flow and vascular biology. Coronary shear stress profiles, reflecting the frictional force exerted by blood flow on the endothelium, have emerged as critical determinants of endothelial health and atherogenesis. The recognition of shear stress as a modifiable risk factor offers new opportunities for early identification and tailored intervention in individuals at risk of adverse cardiovascular events.

Epidemiology / Disease Burden

Globally, over 17 million deaths are attributed to CVD annually, with coronary artery disease (CAD) accounting for a substantial proportion. Epidemiologic studies have highlighted the limitations of conventional risk factors in predicting future events, as many patients experience acute coronary syndromes in the absence of significant luminal stenosis. Shear stress profiling addresses this gap by identifying regions of the vasculature prone to atherosclerotic plaque development and destabilization, thus refining our understanding of disease burden and risk distribution across diverse populations.

Pathophysiology

Shear stress modulates endothelial function via mechanotransduction pathways, influencing gene expression, nitric oxide production, and inflammatory signaling. Physiologically, high laminar shear stress maintains endothelial integrity and suppresses atherogenic processes. In contrast, regions exposed to low or oscillatory shear stress, such as bifurcations and inner curves of arteries, exhibit increased permeability, leukocyte adhesion, and propensity for lipid accumulation. This environment fosters the formation of vulnerable plaques prone to rupture, highlighting the mechanistic link between aberrant shear stress and acute coronary events.

Risk Factors

Several clinical and anatomical factors predispose to altered coronary shear stress. These include hypertension, diabetes, dyslipidemia, smoking, and sedentary lifestyle, all of which contribute to endothelial dysfunction and vascular remodeling. Additionally, anatomical variations such as vessel curvature, bifurcation angles, and pre-existing plaques further modulate local hemodynamics. Understanding these risk factors enhances clinicians ability to identify patients at heightened risk for shear stress-induced vascular injury and subsequent cardiovascular events.

Clinical Features

While altered shear stress itself is not directly symptomatic, its consequences manifest as a spectrum of clinical presentations ranging from stable angina to acute coronary syndromes. Patients with plaques located in regions of low shear stress are more likely to experience plaque rupture, thrombosis, and myocardial infarction. Notably, vulnerable plaques identified by imaging modalities often correlate with areas of disturbed flow, underscoring the clinical relevance of shear stress assessment in risk prediction and patient management.

Diagnosis

Advances in coronary imaging, including intravascular ultrasound (IVUS), optical coherence tomography (OCT), and coronary computed tomography angiography (CCTA), have facilitated in vivo assessment of shear stress profiles. Computational fluid dynamics (CFD) applied to three-dimensional reconstructions of coronary arteries allows for detailed mapping of local shear stress distributions. These techniques enable the identification of high-risk vascular segments and inform both diagnostic and therapeutic decision-making, particularly in patients with intermediate lesions or ambiguous clinical presentations.

Treatment & Management

Current management strategies for patients with high-risk shear stress profiles align with general principles of atherosclerotic cardiovascular disease prevention, including aggressive risk factor modification, antiplatelet therapy, and lipid-lowering interventions. Emerging data suggest that targeted interventions, such as stent placement or surgical revascularization, may modify local shear stress and stabilize vulnerable plaques. The integration of shear stress profiling into routine clinical practice remains an area of active investigation, with ongoing studies evaluating its impact on patient outcomes and therapeutic decision-making.

Recent Advances / Emerging Therapies

Recent advances in imaging and computational modeling have enhanced the granularity of shear stress assessment, enabling prospective identification of plaques at risk for progression or rupture. Novel pharmacologic agents targeting endothelial function and mechanotransduction pathways are under investigation, with the aim of mitigating the adverse effects of disturbed flow. Additionally, personalized medicine approaches leveraging shear stress data are being explored to optimize the timing and selection of interventional therapies in high-risk patients.

Guideline Recommendations

While major cardiovascular societies acknowledge the pathophysiological importance of shear stress, routine clinical assessment is not yet formally incorporated into risk stratification algorithms. However, expert consensus supports the use of advanced imaging to guide management in selected populations, particularly those with ambiguous or intermediate-risk lesions. Ongoing trials and guideline updates are anticipated as the evidence base for shear stress profiling continues to grow.

Conclusion

Coronary shear stress profiles represent a promising frontier in cardiovascular risk assessment, offering mechanistic insights and potential for improved prediction of adverse events. Integration of shear stress data with traditional risk factors and advanced imaging modalities may enable more precise identification of high-risk individuals and inform personalized therapeutic strategies. Continued research and guideline evolution will be critical to realizing the full clinical potential of shear stress profiling in the management of coronary artery disease.