Nishath Altaf

Detection of intraplaque hemorrhage by magnetic resonance imaging in symptomatic patients with mild to moderate carotid stenosis predicts recurrent neurological events.

BACKGROUND Carotid endarterectomy is beneficial in severe (>70%) symptomatic carotid stenosis. The risk of stroke in moderate carotid stenosis (50%-69%) is modest, and so the role of carotid endarterectomy in this group is unclear. Intraplaque hemorrhage is associated with advanced atherosclerosis and can be detected in the carotid arteries by magnetic resonance imaging. This study evaluates whether magnetic resonance imaging detected intraplaque hemorrhage (MR IPH) can identify patients with symptomatic mild to moderate carotid stenosis who are at higher risk of ipsilateral transient ischemic attack (TIA) and stroke. METHODS Prospective longitudinal cohort study of symptomatic patients with mild to moderate (30%-69%) carotid stenosis followed up for 2 years after imaging for IPH using magnetic resonance imaging. RESULTS Sixty four participants were followed up for a median of 28 months (interquartile range 26-30) after MRI of the carotid arteries. Thirty-nine (61%) ipsilateral arteries showed intraplaque hemorrhage. During follow-up, five ipsilateral strokes and a total of 14 ipsilateral ischemic events were observed. Thirteen of these ischemic events, of which five were strokes, occurred in those with ipsilateral carotid intraplaque hemorrhage (hazard ratio = 9.8, 95% confidence interval 1.3-75.1, P = .03). CONCLUSIONS MR IPH is a good predictor of ipsilateral stroke and TIA in patients with symptomatic mild to moderate (30%-69%) carotid stenosis. This technique could help in the selection of patients for carotid endarterectomy.

Carotid Intraplaque Hemorrhage Predicts Recurrent Symptoms in Patients With High-Grade Carotid Stenosis

Background and Purpose— Carotid intraplaque hemorrhage (IPH), known to be associated with plaque instability, may convey a higher stroke risk. The aim of this study was to assess whether the identification of IPH by MRI predicts recurrent clinical cerebrovascular events. Methods— Sixty-six patients with high-grade symptomatic carotid stenosis underwent MRI of the carotid arteries and were followed until carotid endarterectomy or 30 days. Results— Of the 66 patients with a median follow up of 33.5 days, 44 (66.7%) were found on MRI to have ipsilateral carotid IPH. Fifteen recurrent events were associated with ipsilateral carotid IPH. Only 2 recurrent events occurred in the absence of IPH. IPH increased the risk of recurrent ischemia (hazard ratio=4.8; 95% CI=1.1 to 20.9, P<0.05). Conclusion— IPH as detected by MRI predicts recurrent cerebrovascular events in patients with symptomatic high-grade carotid stenosis.

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

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.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. ANN NEUROL 2013;73:774–784

Brain white matter hyperintensities are associated with carotid intraplaque hemorrhage

PURPOSE To retrospectively assess the relationship between carotid intraplaque hemorrhage (IPH), which indicates plaque instability, and brain white matter hyperintense lesions (WMHLs) by using a within-patient design. MATERIALS AND METHODS All patients gave written informed consent for the initial magnetic resonance (MR) studies, and the institutional review board and local research ethics committee waived initial informed consent for the pooled analysis. A total of 190 patients with symptomatic carotid artery disease underwent fluid-attenuated inversion-recovery imaging of the brain and fat-suppressed black-blood T1-weighted MR imaging of the carotid arteries. The volumes of periventricular lesions, subcortical lesions, and total WMHLs were calculated and compared between hemispheres in relation to symptoms and IPH, and their interaction was calculated and compared by using repeated measures three-factorial multivariate analysis. RESULTS After exclusion of 12 patients, 178 patients (116 men, 62 women; mean age, 70.2 years +/- 8.6 [standard deviation]) remained. There was no significant difference in WMHL volume between the symptomatic and asymptomatic hemispheres, and WMHL volume was not related to the degree of carotid stenosis. The presence of carotid IPH significantly interacted with the interhemispheric WMHL difference (Wilks lambda test, F = 9.95; df = 3; P < .001). Univariate analysis showed larger total and periventricular WMHL volumes (P < .05) in patients with ipsilateral IPH. CONCLUSION Carotid artery disease and leukoaraiosis were associated with features that indicated plaque instability, namely IPH, whereas the degree of stenosis had no effect.

Plaque Hemorrhage Is a Marker of Thromboembolic Activity in Patients with Symptomatic Carotid Disease

PURPOSE To assess whether carotid plaque hemorrhage depicted with magnetic resonance (MR) imaging was associated with thromboembolic activity as assessed with transcranial Doppler imaging. MATERIALS AND METHODS The local research ethics committee approved the study, and all patients gave informed written consent. Between April 2005 and December 2006, patients with high-grade symptomatic carotid stenosis were prospectively recruited. All underwent MR imaging of the carotid arteries for plaque hemorrhage and diffusion-weighted imaging of the brain. Transcranial Doppler imaging of the symptomatic carotid artery was performed over 1 hour to assess the presence of microembolic signal. To determine the relationship between the presence of plaque hemorrhage and diffusion-weighted imaging-positive signal and presence of microembolic signal, a logistic regression analysis was performed. RESULTS Fifty-one patients (23 women and 28 men; mean age ± standard deviation, 72 years ± 11) underwent complete MR imaging; 46 (86%) of these patients underwent complete transcranial Doppler imaging. In 32 (63%) patients, there was plaque hemorrhage in the index carotid artery. The presence of plaque hemorrhage increased the risk for ipsilateral abnormalities at diffusion-weighted imaging (odds ratio, 6.2 [95% confidence interval: 1.7, 21.8]; P < .05). Multiple diffusion-weighted imaging-depicted abnormalities of multiple ages were present exclusively in patients with plaque hemorrhage shown at MR imaging (12 of 32 [38%] patients with plaque hemorrhage versus none of 19 patients without plaque hemorrhage; P < .05). The presence of plaque hemorrhage also increased the presence of microembolic signal (odds ratio, 6.0 [95% confidence interval: 1.8, 19.9]; P = .003). CONCLUSION In patients with carotid plaque hemorrhage demonstrated at MR imaging, there was increased spontaneous microembolic activity at transcranial Doppler imaging and cerebral ischemic lesion patterns suggestive of recurrent embolic events; these findings suggest that plaque hemorrhage shown at MR imaging might be a marker of thromboembolic activity and further validate the usefulness of carotid imaging in identifying patients with active carotid arterial disease.

Emergency Endovascular Repair of Aortocaval Fistula-A Single Center Experience

Purpose: To review the outcomes of patients undergoing emergency endovascular repair of aortocaval fistula (ACF) secondary to abdominal aortic aneurysm (AAA). Case Report: Four consecutive patients who underwent emergency endovascular repair of ACF associated with AAA in a tertiary institution between 2002 and 2009. Of the 4 patients, 3 had initially been misdiagnosed and managed for several days by other specialists for their symptoms prior to diagnosis of their ACF. Three patients died in the early postoperative period. The fourth patient made a satisfactory postoperative recovery but subsequently required further endovascular surgery to treat a persistent type 1 endoleak. Conclusions: Our experience illustrates the importance of early diagnosis and management of ACF. Even in experienced hands, the management of spontaneous ACF associated with AAA is challenging. Endovascular surgery may still have a role in improving outcomes in these patients.

The Importance of Anatomical Suitability and Fitness for the Outcome of Endovascular Repair of Ruptured Abdominal Aortic Aneurysm

INTRODUCTION Endovascular repair of aortic aneurysm (EVAR) has a lower mortality than open repair. The aim of this study was to assess mortality from EVAR for emergency AAA repair and the impact of fitness for operation and adverse anatomy. METHODS One-hundred and forty two patients who had EVAR for a ruptured AAA (80, REVAR) or a symptomatic AAA (62, SEVAR) between 1994 and 2007 in a single specialist endovascular centre were reviewed. Fitness for surgery was assessed by Hardmans index (age>76, loss of consciousness, Hb<9.0, Cr>190, ischaemic ECG). CT scans were reviewed, compared with operative images and operation notes for adverse anatomy. Details of perioperative complications, and outcome were recorded. RESULTS Overall mortality at 24-h, 30-days and one year were, respectively: 17%, 36%, 50% for REVAR and 5%, 8%, 23% for SEVAR. Overall adverse anatomy increased 30-day mortality. Hardmans index of three or more increased mortality HR=2.59 (1.24-5.41), p=0.01. On Cox regression Univariate analysis increasing Hardmans index score and adverse anatomy increased the overall mortality over time. In multivariate Cox regression analysis (controlled for the Hardmans index) adverse anatomy was associated with significant increase in graft related mortality. CONCLUSION The use of EVAR is feasible in patients who present with a ruptured or acutely symptomatic AAA. Care must be taken not to extend anatomical or clinical guidelines.

Risk factors associated with cerebrovascular recurrence in symptomatic carotid disease: a comparative study of carotid plaque morphology, microemboli assessment and the European Carotid Surgery Trial risk model.

Background The European Carotid Surgery Trial (ECST) risk model is a validated tool for predicting cerebrovascular risk in patients with symptomatic carotid disease. Carotid plaque hemorrhage as detected by MRI (MRIPH) and microembolic signals (MES) detected by transcranial Doppler (TCD) are 2 emerging modalities in assessing instability of the carotid plaque. The aim of this study was to assess the strength of association of MES and MRIPH with cerebrovascular recurrence in patients with symptomatic carotid artery disease in comparison with the ECST risk prediction model. Methods and Results One hundred and thirty‐four prospectively recruited patients (mean [SD]: age 72 [9.8] years, 33% female) with symptomatic severe (50% to 99%) carotid stenosis underwent preoperative TCD, MRI of the carotid arteries to assess MES, PH, and the ECST risk model. Patients were followed up until carotid endarterectomy, recurrent cerebral event, death, or study end. Event‐free survival analysis was done using backward conditional Cox regression analysis. Of the 123 patients who had both TCD and MRI, 82 (66.7%) demonstrated PH and 46 (37.4%) had MES. 37 (30.1%) cerebrovascular events (21 transient ischemic attacks, 6 amaurosis fugax, and 10 strokes) were observed. Both carotid PH (HR=8.68; 95% CI 2.66 to 28.40, P<0.001) as well as MES (HR=3.28; 95% CI 1.68 to 6.42, P=0.001) were associated with cerebrovascular event recurrence. Combining MES and MRIPH improved the strength of association (HR=0.74, 95% CI 0.65 to 0.83; P<0.001). The ECST risk model was not associated with recurrence (HR=0.86; 95% CI 0.45 to 1.65; P=0.65). Conclusions The presence of carotid plaque hemorrhage is better associated with recurrent cerebrovascular events in patients with symptomatic severe carotid stenosis than the presence of microembolic signals; combining MES and MRIPH, further improves the association while the ECST risk score was insignificant.

Lower prevalence of carotid plaque hemorrhage in women, and its mediator effect on sex differences in recurrent cerebrovascular events.

Background and Purpose Women are at lower risk of stroke, and appear to benefit less from carotid endarterectomy (CEA) than men. We hypothesised that this is due to more benign carotid disease in women mediating a lower risk of recurrent cerebrovascular events. To test this, we investigated sex differences in the prevalence of MRI detectable plaque hemorrhage (MRI PH) as an index of plaque instability, and secondly whether MRI PH mediates sex differences in the rate of cerebrovascular recurrence. Methods Prevalence of PH between sexes was analysed in a single centre pooled cohort of 176 patients with recently symptomatic, significant carotid stenosis (106 severe [≥70%], 70 moderate [50–69%]) who underwent prospective carotid MRI scanning for identification of MRI PH. Further, a meta-analysis of published evidence was undertaken. Recurrent events were noted during clinical follow up for survival analysis. Results Women with symptomatic carotid stenosis (50%≥) were less likely to have plaque hemorrhage (PH) than men (46% vs. 70%) with an adjusted OR of 0.23 [95% CI 0.10–0.50, P<0.0001] controlling for other known vascular risk factors. This negative association was only significant for the severe stenosis subgroup (adjusted OR 0.18, 95% CI 0.067–0.50) not the moderate degree stenosis. Female sex in this subgroup also predicted a longer time to recurrent cerebral ischemic events (HR 0.38 95% CI 0.15–0.98, P = 0.045). Further addition of MRI PH or smoking abolished the sex effects with only MRI PH exerting a direct effect. Meta-analysis confirmed a protective effect of female sex on development of PH: unadjusted OR for presence of PH = 0.54 (95% CI 0.45–0.67, p<0.00001). Conclusions MRI PH is significantly less prevalent in women. Women with MRI PH and severe stenosis have a similar risk as men for recurrent cerebrovascular events. MRI PH thus allows overcoming the sex bias in selection for CEA.

Mid-term Results of Endovascular Aortic Aneurysm Repair in the Young

OBJECTIVES To compare the mid-term outcome and secondary intervention rate following elective open and endovascular aortic aneurysm repair (EVAR) in patients aged 65 years and younger. METHODS A retrospective analysis of patients aged 65 years and younger who had elective abdominal aortic aneurysm repair (AAA) between 1994 and 2012. RESULTS One hundred and sixty-five patients under the age of 65 years (mean age: 61 years ± 4; 8 women) had elective abdominal aneurysm repair (97 EVAR and 68 open). The overall 30-day mortality rate was 3.7% (2.1% EVAR and 5.9% open). Forty per cent of patients had died at a median follow up of 77 months (interquartile range, 36-140). Most deaths were not related to aneurysm. There was no difference in the long-term mortality between the EVAR and open groups (hazard ratio [HR] = 1.22; 95% confidence interval [CI] 0.75-1.98, p = .43), but there was a trend of better outcomes with the use of commercially made endografts over open repair (HR = 2.9; 95% CI 0.9-10.0, p = .08) and custom-made endografts (HR = 3.1, 95% CI 0.9-10.3; p = .07). Eleven per cent of patients who had EVAR required a further procedure compared with 13% who had open repair. All but one of the re-interventions in the EVAR group was performed on patients who had custom-made endografts. CONCLUSIONS Young patients with AAA have significant comorbidities and do not necessarily have long lifespans. In the less fit younger patients with AAA, the results with EVAR are comparable with fit patients who had open AAA repair. The management of fitter young patients with AAA remains controversial, but improving results with EVAR over time may increase the role of EVAR in this group.