Coronary and carotid atherosclerosis: similarities and differences

Although a relationship is commonly accepted between coronary and carotid arterial disease, suggesting that atherosclerosis is a systemic condition, the extent of this association and correspondence has not been fully elucidated. This review discusses recent research in this field and highlights areas for future study. The prevalence of severe carotid stenosis increases with prevalence of coronary stenosis, with the latter being found in a significant number of stroke patients, while those with carotid stenosis may be at higher risk of myocardial infarction than stroke. There also appear to be common risk factors (age, diabetes, hypertension, smoking and dyslipidemia), although the effects in both vascular systems may not be identical. Furthermore, while the degree of stenosis in the coronary artery has little ability to predict acute coronary syndrome, which is caused by local thrombosis from a ruptured or eroded plaque, severe carotid stenosis causing hypoperfusion is highly predictive of stroke, although this effect may be time-limited. This apparent difference in event mechanism in the two arteries is interesting as is the difference in the rate of development of collaterals. Overall, the evidence shows that a clear relationship exists between disease in the coronary and carotid arteries, since conventional risk factors and the extent of stenosis and/or previous events emanating from one artery have a strong bearing on the prevalence of events in the other artery. Nevertheless, the exact correspondence between the two arteries is unclear, with sometimes contradictory study results. More research is needed to identify the full extent of risk factors for severe stenosis and cardio- or cerebral vascular events, among which, inflammatory biomarkers such as hs-CRP and prior vascular events are likely to play a key role.