Blood Biomarkers in Ischemic Stroke
Relevance of Carotid Plaque Characteristics for Ischemic Stroke and Coronary Heart Disease
Selwaness M, Bos D, van den Bouwhuijsen Q, Portegies MLP, Ikram MA, Hofman A, et al. Carotid Atherosclerotic Plaque Characteristics on Magnetic Resonance Imaging Relate With History of Stroke and Coronary Heart Disease. Stroke. 2016
Intracranial Atherosclerosis and Coronary Atherosclerosis: Two Twigs from the Same Vascular Branch
Chung J-W, Bang OY, Lee MJ, Hwang J, Cha J, Choi J-H, et al. Echoing Plaque Activity of the Coronary and Intracranial Arteries in Patients With Stroke. Stroke. 2016
Atherosclerosis is a diffuse process that can affect both the coronary and carotid arteries, but while previous studies have suggested a strong correlation between coronary atherosclerosis and extracranial carotid atherosclerosis, the correlation with intracranial atherosclerosis is less clear. Whereas the mechanism of myocardial infarction from coronary atherosclerosis is likely more similar to ischemic stroke caused by extracranial atherosclerosis, ischemic stroke caused by intracranial atherosclerosis typically falls into two etiologies: branch occlusive disease-type (B-type), where atherosclerosis occludes a perforating artery, versus coronary-type plaque rupture of plaque (C-type), where the atherosclerotic plaque ruptures, causing a shower of multiple embolic infarcts distally. This study attempts to characterize intracranial plaque phenotypes and correlate asymptomatic coronary artery disease (CAD) with intracranial atherosclerotic disease (ICAD) burden.
A total of 81 patients were included the final analysis, drawn from a population of patients admitted within 7 days of symptom onset for treatment of acute ischemic stroke with intracranial atherosclerosis. Patients who had known histories of coronary artery disease were excluded. B-type ICAS was differentiated from C-type ICAS in both anterior and posterior territory strokes. An ICAD score was calculated on the basis of intracranial atherosclerotic burden, with 0 points given for stenosis less than 50%, 1 point for stenosis of 50-99% and 2 points for an occlusion, with all involved intracranial vessels summed for a total score
Asymptomatic CAD was quite common, with a prevalence of just over 80% in the study population. The prevalence of asymptomatic CAD was relatively similar in both B-type and C-type ICAS groups (48% vs 52%) and, as might be expected, the burden of ICAD was positively correlated with the burden of CAD, although non-calcified coronary artery plaque morphology was independently associated with C-type ICAS. As non-calcified coronary plaque increased, remodeling also increased in the symptomatic arteries of patients with ICAS.
This study provides evidence of a positive relationship between coronary and intracranial atherosclerotic burden, and that coronary artery plaque composition (calcified vs non-calcified) might predict intracranial atherosclerosis morphology. The investigators suggest that this should prompt us as clinician to take a more holistic approach to the entire vascular system, rather than solely focus on, for example, the cerebral vasculature, or the coronary arteries. Certainly this might prompt the clinician to, when faced with a stroke patient with C-type ICAS, be more cognizant of the type of likely associated CAD burden, but a study evaluating whether this might also be predictive of acute coronary syndrome, would be of additional benefit.
PCI Setting Has Little Effect on Post-Stroke Cardiovascular Outcomes and Mortality
Benjamin Kummer, MD
Myint PK, Kwok CS, Roffe C, Kontopantelis E, Zaman A, Berry C, et al. Determinants and Outcomes of Stroke Following Percutaneous Coronary Intervention by Indication. Stroke. 2016.
Percutaneous coronary intervention (PCI) is infrequently complicated by stroke, which tends to occur more frequently after emergent PCI, and is highly morbid when it occurs. However, the relationship between PCI setting (emergent vs. elective) or stroke subtype (ischemic vs. hemorrhagic) and stroke risk factors, as well as post-PCI stroke outcomes, remains unclear. Myint et al. sought to address these gaps in knowledge by studying approximately 560,000 PCI patients from the British Cardiovascular Intervention Society database, using in-hospital major adverse cardiovascular events (MACE) and 30-day mortality as outcomes.
The rate of any post-PCI stroke was low (0.13%), 80% of strokes were ischemic, and any post-PCI stroke was associated with increased odds of poor outcome irrespective of setting (ORs, no stroke as reference: elective MACE 21.05, p<0.001, emergent MACE 6.25, p<0.001, elective mortality 37.90, p<0.001, emergent mortality 5.00, p<0.001). ORs were higher in the elective vs. emergent setting. The odds of mortality after hemorrhagic stroke (ORs: elective 175.24, p<0.001, emergent 21.50, p<0.001) were higher than after ischemic stroke irrespective of setting (ORs: elective 17.61, p<0.001, emergent 3.11, p<0.001), consistent with the high mortality associated with ICH.
Generally, setting did not significantly affect the odds of poor outcome—except for ischemic stroke after emergent PCI, which had lower odds of in-hospital MACE than after ischemic stroke in the elective setting (OR 0.44, 95%CI 0.22-0.86). The authors attributed this to higher usage of “advanced” anti-platelet medications / GP IIb/IIIa inhibitors in emergent PCI settings.
Stroke risk factors differed by PCI setting. Female sex and cardiovascular comorbidities such as CABG, cardiogenic shock, ventilator/circulatory support and STEMI were associated with increased odds of stroke in the emergent setting, whereas female sex and the use of GP IIb/IIIa inhibitors were the main risk factors for the elective setting. There were also differences in risk factors according to stroke subtype; thrombectomy was associated with ischemic stroke, whereas thrombolysis was associated with hemorrhagic stroke. The main limitations were unclear ascertainment of stroke, absent functional status data and post-stroke management, plus the impossibility of gauging the timing of stroke in relation to PCI.
Overall, the study confirms the rarity and known high morbidity and mortality of post-PCI stroke once it occurs, and also shows that risk factors vary between stroke subtypes and settings. However, PCI setting does not seem to have major impact on the likelihood of poor outcome after post-PCI stroke.
Residual Arterial Stenosis after Endovascular Thrombectomy: a Relationship with in Situ Thrombo-occlusion and Reocclusion Rates
Inverse Relationship between HDL2-C Subfraction and Carotid Intima-Media Thickness
Tiozzo E, Gardener H, Hudson BI, Dong C, Della-Morte D, Crisby M, et al. Subfractions of High-Density Lipoprotein-Cholesterol and Carotid Intima-Media Thickness: The Northern Manhattan Study. Stroke. 2016
Increased carotid-intima media thickness (cIMT) is associated with future cerebrovascular events. Although previous data has shown an inverse relationship between high density lipoprotein cholesterol (HDL-C) and future cerebrovascular events, this association has been challenged in recent trials; therefore, it is uncertain whether HDL-C subfractions have differential effects on cerebrovascular risk.