Magnetic resonance imaging plaque hemorrhage for risk stratification in carotid artery disease with moderate risk under current medical therapy

Background and Purpose—Magnetic resonance imaging (MRI)–defined carotid plaque hemorrhage (MRIPH) can predict recurrent cerebrovascular ischemic events in severe symptomatic carotid stenosis. It is less clear whether MRIPH can improve risk stratification despite optimized medical secondary prevention in those with moderate risk. Methods—One-hundred fifty-one symptomatic patients with 30% to 99% carotid artery stenosis (median age: 77, 60.5% men) clinically deemed to not benefit from endarterectomy were prospectively recruited to undergo MRI and clinical follow-up (mean, 22 months). The clinical carotid artery risk score could be evaluated in 88 patients. MRIPH+ve was defined as plaque intensity >150% that of adjacent muscle. Survival analyses were performed with recurrent infarction (stroke or diffusion-positive cerebral ischemia) as the main end point. Results—Fifty-five participants showed MRIPH+ve; 47 had low, 36 intermediate, and 5 high carotid artery risk scores. Cox regression showed MRIPH as a strong predictor of future infarction (hazard ratio, 5.2; 95% confidence interval, 1.64–16.34; P=0.005, corrected for degree of stenosis), also in the subgroup with 50% to 69% stenosis (hazard ratio, 4.1; 95% confidence interval, 1–16.8; P=0.049). The absolute risk of future infarction was 31.7% at 3 years in MRIPH+ve versus 1.8% in patients without (P<0.002). MRIPH increased cumulative risk difference of future infarction by 47.1% at 3 years in those with intermediate carotid artery risk score (P=0.004). Conclusions—The study confirms MRIPH to be a powerful risk marker in symptomatic carotid stenosis with added value over current risk scores. For patients undergoing current secondary prevention medication with clinically uncertain benefit from recanalization, that is, those with moderate degree stenosis and intermediate carotid artery risk scores, MRIPH offers additional risk stratification

Carotid plaque hemorrhage on magnetic resonance imaging strongly predicts recurrent ischemia and stroke

Objective There is a recognized need to improve selection of patients with carotid artery stenosis for carotid endarterectomy (CEA). We assessed the value of magnetic resonance imaging (MRI)-defined carotid plaque hemorrhage (MRIPH) to predict recurrent ipsilateral cerebral ischemic events, and stroke in symptomatic carotid stenosis. Methods One hundred seventy-nine symptomatic patients with ≥50% stenosis were prospectively recruited, underwent carotid MRI, and were clinically followed up until CEA, death, or ischemic event. MRIPH was diagnosed if the plaque signal intensity was >150% that of the adjacent muscle. Event-free survival analysis was done using Kaplan–Meier plots and Cox regression models controlling for known vascular risk factors. We also undertook a meta-analysis of reported data on MRIPH and recurrent events. Results One hundred fourteen patients (63.7%) showed MRIPH, suffering 92% (57 of 62) of all recurrent ipsilateral events and all but 1 (25 of 26) future strokes. Patients without MRIPH had an estimated annual absolute stroke risk of only 0.6%. Cox multivariate regression analysis proved MRIPH as a strong predictor of recurrent ischemic events (hazard ratio [HR] = 12.0, 95% confidence interval [CI] = 4.8–30.1, p < 0.001) and stroke alone (HR = 35.0, 95% CI = 4.7–261.6, p = 0.001). Meta-analysis of published data confirmed this association between MRIPH and recurrent cerebral ischemic events in symptomatic carotid artery stenosis (odds ratio = 12.2, 95% CI = 5.5–27.1, p < 0.00001). Interpretation MRIPH independently and strongly predicts recurrent ipsilateral ischemic events, and stroke alone, in symptomatic ≥50% carotid artery stenosis. The very low stroke risk in patients without MRIPH puts into question current risk–benefit assessment for CEA in this subgroup

Clinical Comparison of Outcomes of Early versus Delayed Carotid Artery Stenting for Symptomatic Cerebral Watershed Infarction due to Stenosis of the Proximal Internal Carotid Artery

The aim of this study was to compare the clinical outcomes of early versus delayed carotid artery stenting (CAS) for symptomatic cerebral watershed infarction (sCWI) patients due to stenosis of the proximal internal carotid artery. We retrospectively collected clinical data of those who underwent early or delayed CAS from March 2011 to April 2014. The time of early CAS and delayed CAS was within a week of symptom onset and after four weeks from symptom onset. Clinical data such as second stroke, the National Institutes of Health Stroke Scale (NHISS) score, and modified Rankin Scale (mRS) score and periprocedural complications were collected. The rate of second stroke in early CAS group is lower when compared to that of delayed CAS group. There was no significant difference regarding periprocedural complications in both groups. There was a significant difference regarding mean NHISS score 90 days after CAS in two groups. Early CAS group had a significant better good outcome (mRS score ≤ 2) than delayed CAS group. We suggest early CAS for sCWI due to severe proximal internal carotid artery stenosis as it provides lower rate of second stroke, comparable periprocedural complications, and better functional outcomes compared to that of delayed CAS

Groin wound infection after vascular exposure ( GIVE ) multicentre cohort study

Surgical site infections (SSIs) of groin wounds are a common and potentially preventable cause of morbidity, mortality, and healthcare costs in vascular surgery. Our aim was to define the contemporaneous rate of groin SSIs, determine clinical sequelae, and identify risk factors for SSI. An international multicentre prospective observational cohort study of consecutive patients undergoing groin incision for femoral vessel access in vascular surgery was undertaken over 3 months, follow‐up was 90 days. The primary outcome was the incidence of groin wound SSI. 1337 groin incisions (1039 patients) from 37 centres were included. 115 groin incisions (8.6%) developed SSI, of which 62 (4.6%) were superficial. Patients who developed an SSI had a significantly longer length of hospital stay (6 versus 5 days, P = .005), a significantly higher rate of post‐operative acute kidney injury (19.6% versus 11.7%, P = .018), with no significant difference in 90‐day mortality. Female sex, Body mass index≥30 kg/m2, ischaemic heart disease, aqueous betadine skin preparation, bypass/patch use (vein, xenograft, or prosthetic), and increased operative time were independent predictors of SSI. Groin infections, which are clinically apparent to the treating vascular unit, are frequent and their development carries significant clinical sequelae. Risk factors include modifiable and non‐modifiable variables

Groin wound infection after vascular exposure (GIVE) multicentre cohort study

Surgical site infections (SSIs) of groin wounds are a common and potentially preventable cause of morbidity, mortality, and healthcare costs in vascular surgery. Our aim was to define the contemporaneous rate of groin SSIs, determine clinical sequelae, and identify risk factors for SSI. An international multicentre prospective observational cohort study of consecutive patients undergoing groin incision for femoral vessel access in vascular surgery was undertaken over 3 months, follow-up was 90 days. The primary outcome was the incidence of groin wound SSI. 1337 groin incisions (1039 patients) from 37 centres were included. 115 groin incisions (8.6%) developed SSI, of which 62 (4.6%) were superficial. Patients who developed an SSI had a significantly longer length of hospital stay (6 versus 5 days, P = .005), a significantly higher rate of post-operative acute kidney injury (19.6% versus 11.7%, P = .018), with no significant difference in 90-day mortality. Female sex, Body mass index≥30 kg/m2, ischaemic heart disease, aqueous betadine skin preparation, bypass/patch use (vein, xenograft, or prosthetic), and increased operative time were independent predictors of SSI. Groin infections, which are clinically apparent to the treating vascular unit, are frequent and their development carries significant clinical sequelae. Risk factors include modifiable and non-modifiable variables

Arterial stiffness and haemorrhage in the vulnerable carotid plaque

Background Magnetic resonance imaging of carotid plaque haemorrhage (MRIPH) has recently been shown to be more superior than the degree of stenosis in predicting ischaemic stroke. Recently, mechanical factors such as arterial stiffness have also been suggested to be associated with stroke. Pulse wave velocity (PWV) is a non-invasive imaging technique to assess arterial stiffness and studies have shown that aortic PWV is an independent predictor of cardiovascular and cerebrovascular morbidity as well as mortality. The aims of this thesis were to test the feasibility of assessing carotid PWV using magnetic resonance imaging (MRI), to examine the association between carotid PWV and the degree of stenosis as well as the association between the status of MRIPH and carotid PWV. Methods 29 patients (55 carotid arteries) with at least 50% unilateral carotid artery stenosis and 8 healthy volunteers (16 carotid arteries) were included in the study. PWV was derived from cine phase contrast using MRI at 3 Tesla. Carotid PWV was compared between the two groups, the relationship between carotid PWV and the degree of carotid stenosis as well as the presence of MRIPH were examined. All multiple linear and logistic regression analyses were adjusted for age and blood pressure. Results Repeatability for the measurement of carotid PWV was good (Cronbach's Alpha=0.703; Bland-Altman plot bias=0.25, upper and lower limits of agreement=+4.23, -3.74; n=16). Similarly, there was good intra-observer consistency (Cronbach's Alpha=0.747; Bland-Altman plot bias=0.06, upper and lower limits of agreement=+1.90, -1,78; n=13). The mean difference in transit time with and without static phantom correction for background velocity was 0.12 ms, P=0.4. There was no significant difference in carotid PWV in healthy volunteers (median [IQR]: 4.1 m/s [2.8-5.60]) and patients with carotid artery stenosis (70-99%: 3.5 m/s [1.4-3.5], 50-69%: 4.9 m/s [2.5-5.3], <30%: 4.5 m/s [2.3-5.8]). There was also no association between carotid PWV and the degree of carotid stenosis (R2=0.055, P=0.943). However, carotid PWV was significantly associated with increasing age group (R2=0.35, P=0.001). None of the blood pressure parameters were significantly associated with carotid PWV (systolic blood pressure, R2=0.047, P=0.07; diastolic blood pressure, R2=0.007, P=0.5; pulse pressure, R2=0.038, P=0.1; and mean arterial blood pressure, R2=0.028, P=0.1). There was a trend for higher PWV in carotids with MRIPH+ (4.14 m/s [1.9-4.7] versus 3.0 m/s [1.9-4.7], P=0.09), but it was insignificant. However, MRIPH+ carotid arteries were significantly associated with higher carotid PWV after adjusting for age, blood pressure and the degree of carotid stenosis (OR 1.22, 95% CI 1.02-1.47, P=0.03). This association was maintained even after exclusion of high grade carotid stenosis due to potential error in image acquisition in this group (OR 1.21, 95% CI 0.99-1.48, P=0.05). Furthermore, symptomatic carotid stenosis was found to have higher value of carotid PWV compared to asymptomatic ones (OR 1.39, 95% CI 1.0-1.8, P=0.007). Conclusion This study has demonstrated the feasibility of assessing PWV in the carotid arteries with MRI. However, more work is needed to optimise the temporal and spatial resolution of the MRI sequence and to validate the technique. The association between MRIPH and carotid PWV requires further study with a larger cohort of symptomatic patients