Acute Symptomatic Internal Carotid Artery Research Articles

Management and prognosis of acute extracranial internal carotid artery occlusion.

Acute occlusion of the internal carotid artery is the underlying etiology in 4 to 15% of all ischemic strokes. The clinical presentation varies considerably ranging from asymptomatic occlusion to severe ischemic strokes. Substantial differences in the acute management of acute symptomatic internal carotid artery occlusions (ICAO) exists between centers. Thusly, we comprised a narrative review of the natural course of acute ICAO and of available treatment options [i.v. thrombolysis, endovascular thrombectomy and stenting, bypass between the superficial temporal and the middle cerebral arteries (MCA) and carotid endarterectomy (CEA)]. We found that very few randomized treatment trials have been performed in patients acute symptomatic ICAO. Most evidence stems from case series and observational studies. Especially in older studies the intracranial vessel status has rarely been considered. After revision of these studies we concluded that the mainstay of the acute management of acute symptomatic ICAO is i.v. thrombolysis when applied within the label and in combination with mechanical thrombectomy in case of intracranial large vessel occlusion. In cases without intracranial large vessel occlusion mechanical thrombectomy of acute ICAO is associated with a risk of distal embolization. More research on prognostic parameters is needed to better characterize the risk of decompensation of collateral flow and to better define the time-window of intervention. When mechanical thrombectomy fails or is not available, surgical approaches are an alternative in selected patients.

Abstract TP137: Characteristics of Perfusion Profiles in Patients With Chronic Internal Carotid Artery Occlusion

Introduction: Internal carotid artery (ICA) occlusion may cause an acute stroke or may remain asymptomatic for years. Differences in the perfusion characteristics between patients with acute symptomatic ICA occlusions and those with chronic ICA occlusions have not been defined. The aim of this study is to identify the characteristics of the relatively “benign” perfusion pattern associated with chronic asymptomatic ICA occlusions and to determine if this pattern can be differentiated from the pattern observed in acutely symptomatic cases. Methods: We included 31 chronic ICA patients who had no history of a cerebral ischemic event for at least 1 year at the time of imaging and 20 patients with acute ischemic stroke caused by ICA occlusions from DEFUSE 2. All patients underwent MRI with perfusion. Perfusion parameters, including Tmax lesion volumes, hypoperfusion index (Tmax10/Tmax6), and CBV index (rCBV in Tmax6) were calculated by RAPID software. The status of the CBV, CBF, and MTT in the ischemic hemisphere was also rated by visual inspection on a 3-point scale (unchanged, reduced or increased). Differences were assessed by Mann-Whitney and Fisher’s exact tests. Results: The average age was 65.0±9.9 years in chronic vs. 64.7±14.2 years in acute ICA occlusion group ( p =0.90). Most of the chronic ICA patients had no territory with Tmax>10s (29/31) or Tmax>8s (24/31) in the ischemic hemisphere. The average Tmax lesion volumes were lower in the chronic ICA group (Tmax>6 of 14 ml and Tmax>4 of 81 ml) than in the acute ICA occlusion group (Tmax>6 of 131 ml and Tmax>4 of 220 ml, p <0.0001 for both, Figure). CBV was unchanged in all chronic occlusion cases. In the acute occlusion group, there were 12 out of 20 cases (60%) with decreased CBV ( p <0.0001). CBF was decreased in 1 (3%) patient with a chronic occlusion and 17 cases (85%) with acute occlusions ( p <0.0001). MTT prolonged in 7 cases (22%) with chronic occlusions vs. all cases (100%) with acute occlusions ( p <0.0001). Conclusions: Several features on perfusion MRI distinguish chronic ICA occlusions from acute occlusions. Patients with chronic ICA occlusions tend to have none or a minimal volume of tissue with Tmax>8s or >10s delay, smaller volumes of tissue with Tmax>4s and >6s delay, and normal appearing CBV and CBF maps.

Emergent Carotid Thromboendarterectomy for Acute Symptomatic Occlusion of the Extracranial Internal Carotid Artery.

Strokes secondary to acute internal carotid artery (ICA) occlusion are associated with an extremely poor prognosis. The best treatment approach in this setting is still unknown. The aim of our study was to evaluate the efficacy, safety, and outcomes of emergent surgical revascularization of acute extracranial ICA occlusion in patients with minor to severe ischemic stroke. A retrospective analysis was performed using prospectively collected data of consecutive patients who underwent carotid thromboendarterectomy for symptomatic acute ICA occlusion during the period from January 2013 to December 2015. Primary outcomes were disability at 90 days assessed by the modified Rankin Scale (mRS) and neurological deficit at discharge assessed using the National Institute of Health Stroke Scale (NIHSS). Secondary outcomes were the recanalization rate, 30-day overall mortality, and any intracerebral bleeding. During the study period, a total of 6 patients (5 men and 1 woman) with a median age of 64 years (range: 58-84 years) underwent emergent reconstruction for acute symptomatic ICA occlusion within a median of 5.4 hours (range: 2.9-12.0 hours) after symptoms onset. The median presenting NIHSS score was 10.5 points (range: 4-21). Before surgery, 4 patients (66.7%) had been treated by systemic recombinant tissue plasminogen activator lysis. The median time interval between initiation of intravenous thrombolysis and carotid thromboendarterectomy was 117.5 minutes (range: 65-140 minutes). Patency of the ICA was achieved in all patients. On discharge, the median NIHSS score was 2 points (range: 0-11 points). There was no postoperative intracerebral hemorrhage and zero 30-day mortality rate. At 3 months, 5 patients (83.3%) had a good clinical outcome (mRS ≤ 2). Patients presenting with minor to severe ischemic stroke syndromes due to isolated extracranial ICA occlusion may benefit from emergent carotid revascularization. Thorough preoperative neuroimaging is essential to aid in selecting eligible candidates for acute surgical intervention.

Time-dependent parameter of perfusion imaging as independent predictor of clinical outcome in symptomatic carotid artery stenosis.

BackgroundCarotid artery stenosis is a frequent cause of ischemic stroke. While any degree of stenosis can cause embolic stroke, a higher degree of stenosis can also cause hemodynamic infarction. The hemodynamic effect of a stenosis can be assessed via perfusion weighted MRI (PWI). Our aim was to investigate the ability of PWI-derived parameters such as TTP (time-to-peak) and Tmax (time to the peak of the residue curve) to predict outcome in patients with unilateral acute symptomatic internal carotid artery (sICA) stenosis.MethodsPatients with unilateral acute sICA stenosis (≥50 % according to NASCET), without intracranial stenosis or occlusion, who underwent PWI, were included. Clinical characteristics, volume of restricted diffusion, volume of prolonged TTP and Tmax were retrospectively analyzed and correlated with outcome represented by the modified Rankin Scale (mRS) score at discharge. TTP and Tmax volumes were dichotomized using a ROC curve analysis. Multivariate analysis was performed to determine which PWI-parameter was an independent predictor of outcome.ResultsThirty-two patients were included. Degree of stenosis, volume of visually assessed TTP and volume of TTP ≥2 s did not distinguish patients with favorable (mRS 0–2) and unfavorable (mRS 3–6) outcome. In contrast, patients with unfavorable outcome had higher volumes of TTP ≥4 s (9.12 vs. 0.87 ml; p = 0.043), TTP ≥6 s (6.70 vs. 0.20 ml; p = 0.017), Tmax ≥4 s (25.27 vs. 0.00 ml; p = 0.043), Tmax ≥6 s (9.21 vs. 0.00 ml; p = 0.017), Tmax ≥8 s (6.86 vs. 0.00 ml; p = 0.011) and Tmax ≥10s (5.94 vs. 0.00 ml; p = 0.025) in univariate analysis. Multivariate logistic regression showed that NIHSS score on admission (Odds Ratio (OR) 0.466, confidence interval (CI) [0.224;0.971], p = 0.041), Tmax ≥8 s (OR 0.025, CI [0.001;0.898] p = 0.043) and TTP ≥6 s (OR 0.025, CI [0.001;0.898] p = 0.043) were independent predictors of clinical outcome.ConclusionAs they stood out in multivariate regression and are objective and reproducible parameters, PWI-derived volumes of Tmax ≥8 s and TTP ≥6 s might be superior to degree of stenosis and visually assessed TTP maps in predicting short term patient outcome. Future studies should assess if perfusion weighted imaging might guide the selection of patients for recanalization procedures.Electronic supplementary materialThe online version of this article (doi:10.1186/s12883-016-0576-5) contains supplementary material, which is available to authorized users.

Abstract TMP14: Baseline Characteristics and Clinical Outcomes of Acute Symptomatic Internal Carotid Artery Stump

Background: Theoretically, recurrent stroke symptoms caused by severe internal carotid artery (ICA) stenosis should resolve on progression of stenosis to complete occlusion. However, stroke symptoms may recur due to the occluded ICA stump (carotid stump syndrome). We investigated the clinical characteristics and treatment outcomes in patients with ICA stump. Methods: Subjects were recruited from a stroke registry at a university hospital (Feb 2005 to Jan 2015). The eligibility criteria were 1) extracranial ICA occlusion on computed tomographic angiography (CTA) as a stump morphology and 2) acute ischemic stroke or transient ischemic attack in the corresponding arterial territory <7 days from symptom onset. The exclusion criteria were 1) presumed etiology as cardiac embolism or other etiology (e.g., dissection, moyamoya syndrome, and vasculitis) and 2) concomitant carotid T type occlusion on CTA. A total of 114 patients were categorized into the stable (N=90) and unstable (N=24) groups. Unstable group indicated stroke recurrence in <3 months, or progression of ischemic stroke during hospitalization. Progression of stroke was defined as 1) change in NIHSS score ≥2 or 2) change of NIHSS score ≥1 with malignant change or increase of infarct size. Intensive statin treatment was defined as ≥10 mg of rosuvastatin and/or ≥20 mg of atorvastatin. Logistic regression analysis was performed to identify prognostic factors. Results: There were no significant inter-group differences with respect to age, sex, and mode of thrombolytic therapy. Metabolic syndrome and initial heparinization were both more frequent in the unstable group than in the stable group. (83.3% vs. 46.7%, p=0.001 and 41.7% vs. 10.0%, p<0.001, respectively). Frequency of intensive statin treatment was lower in the unstable group (41.7% vs. 65.6%, p=0.033). On multivariate analyses, metabolic syndrome, initial heparinization, and non-use of intensive statin therapy were independent risk factors for progression or recurrence. Conclusion: Metabolic syndrome was the main risk factor for progression/recurrence of stroke caused by ICA stump. Intensive statin treatment seems to be beneficial in these patients. The benefits of initial heparinization appear to be questionable.

Short-Term Recanalization of Symptomatic Internal Carotid Artery Occlusion

Background: The natural history of acute symptomatic ICA occlusion remains unclear. Short term follow-up studies have been rarely reported. Therefore, the objective of this study was to determine the natural history of acute ICA occlusion through short-term follow-up. In addition, we determined factors associated with recanalization and poor outcome. Methods: We consecutively enrolled acute ischemic stroke patients within 7 days who had acute symptomatic internal carotid artery occlusion. Demographic data, stroke subtypes, National Institute of Health Stroke Scale (NIHSS) score, and modified Rankin scale score at 3 months were recorded. Carotid duplex ultrasonography, CT angiography, or digital subtraction angiography in 2-9 days after the initial angiography was conducted to check recanalization pattern of ICA. Recanalization was classified into complete, partial, or no recanaliza tion. Results: A total of 64 patients with acute symptomatic ICA occlusion were enrolled in this study. Follow-up vessel studies were completed for 53 patients. Follow-up carotid duplex sonography was performed for 23 patients. CT angiography was performed for 9 patients. Both carotid duplex sonography and CT angiography were performed for 21 patients. Complete recanalization was observed in 5 (9.4%) of the 53 patients. All five patients received thrombolysis. Partial recanalization was observed in 8 (15.1%) patients. The remaining 40 (75.5%) patients did not show recanalization. Cardioembolism (P =0.008) and thrombolytic treatment (P =0.025) were factors associated with complete recanalization. However, recanalization (P >0.999) was not associated with favorable clinical outcome. Conclusion: Recanalization of symptomatic internal carotid artery occlusion was identified in 13 (24.5%) patients. Cardioembolism and thrombolytic treatment were factors significantly associated with complete recanalization. J Neurocrit Care 2015;8(2):103-108

Serum lipids associated with inflammation-related PET-FDG uptake in symptomatic carotid plaque.

We hypothesized that serum lipids, which experimental data suggest may be key initiators of carotid plaque inflammation, would be associated with plaque inflammation on (18)fluorodeoxyglucose (FDG)-PET in patients with acutely symptomatic carotid stenosis. In this cohort study, consecutive patients with acute symptomatic internal carotid artery (ICA) stenosis (≥50%) underwent carotid PET-CT. We quantified plaque FDG uptake as follows: (1) average maximum standardized uptake values (SUVmax) across 10 regions of interest (ROI); (2) highest single ROI SUV measure (SUVROImax); (3) averaged mean SUV across 10 ROIs (SUVmean). Sixty-one patients were included. Plaque inflammatory FDG SUVmax was associated with increasing tertiles of low-density lipoprotein (LDL) (trend p = 0.004), total cholesterol (p = 0.009), and triglycerides (p = 0.01), and with lower high-density lipoprotein (HDL) (p = 0.005). When analyzed as a continuous variable, LDL was associated with symptomatic ICA SUVmean (Spearman rho 0.44, p = 0.009), SUVROImax (rho 0.33, p = 0.01), and SUVmax (rho 0.35, p = 0.06). Total cholesterol was associated with SUVmean (rho 0.33, p = 0.009), with trends for SUVmax (rho 0.24, p = 0.059) and SUVROImax (rho 0.23, p = 0.08). Triglycerides were associated with SUVmax (rho 0.32, p = 0.01) and SUVROImax (rho 0.35, p = 0.005). HDL was associated with lower SUVmax (rho -0.37, p = 0.004) and SUVROImax (rho -0.44, p = 0.0004). On multivariable linear regression analysis adjusting for age, sex, degree of carotid stenosis, statins, and smoking, LDL (p = 0.008) and total cholesterol (p = 0.04) were independently associated with SUVmax. Serum LDL and total cholesterol were associated with acutely symptomatic carotid plaque FDG uptake, supporting experimental data suggesting lipids may promote plaque inflammation, mediating rupture and clinical events.

Endovascular therapy in 201 patients with acute symptomatic occlusion of the internal carotid artery

Endovascular therapy is used increasingly for treatment of acute symptomatic internal carotid artery (ICA) occlusion, although randomized trials are lacking. Predictors of outcome are therefore of special interest. From 1992 to 2010 we treated 201 patients with acute ICA occlusion with intra-arterial pharmacological thrombolysis (32), endovascular mechanical therapy (78) or a combination of both (91). All data were assessed prospectively. There were 76/38% patients with tandem occlusions [ICA plus middle (MCA) or anterior cerebral arteries (ACA)], 18/9% without concomitant occlusions of major intracranial arteries (ICA plus branch occlusion) and 107/53% with functional ICA-T occlusions (ICA plus MCA and ACA). Median baseline National Institute of Health Stroke Scale (NIHSS) score was 17. Good recanalization (Thrombolysis in Myocardial Infarction 2-3) was achieved in (157/201) 78% patients and good reperfusion (Thrombolysis in Cerebral Infarction 2-3) in (151/182) 83%. Better recanalization rates were obtained with mechanical approaches, with/without thrombolytics (78/91 = 86% and 64/78 = 82%) compared with pharmacological thrombolysis only (15/32=47%; P < 0.001). Twelve patients (6%) suffered symptomatic intracranial haemorrhages. The 3-month outcome was favourable [modified Rankin score (mRS) 0-2] in 54/28% patients and moderate (mRS 0-3) in 90/46%; 60/31% patients died. Only 17/16% patients with functional ICA-T occlusions had favourable outcomes compared with 32/44% with tandem occlusions and 5/31% with ICA plus cerebral branch occlusions (P = 0.001). In multivariate analysis age [odds ratio (OR) = 0.96, 95% confidence interval (CI) = 0.93-0.98], NIHSS on admission (OR = 0.9, 95% CI = 0.83-0.98) and functional ICA-T occlusion (OR = 0.35, 95% CI = 0.16-0.77) were non-modifiable predictors, and vessel recanalization was the only modifiable predictor of outcome (OR = 9.30, 95% CI = 2.03-42.63). The outcome of acute symptomatic ICA occlusion is poor. However, recanalization is associated with better outcome, and recanalization rates with mechanical techniques were superior to merely pharmacological recanalization attempts.

Time Is Brain? — Surgical Revascularization of Acute Symptomatic Occlusion of the Internal Carotid Artery up to One Week

Clinical outcome and surgical success rate of open surgical reconstruction for acute symptomatic internal carotid artery (ICA) occlusion up to 1 week after stroke onset were analyzed to determine a cutoff time, after which risk exceeds clinical benefit. From November 1997 to March 2007, a total of 5369 patients were examined at the authors' stroke unit; 502 from this cohort underwent ICA reconstruction. A subgroup of 49 patients underwent surgical revascularization of acute ICA occlusion within 168 hr at a mean of 42.5±38.7 hr after stroke onset. Preoperative diagnostic measures consisted of extracranial/intracranial duplex sonography (n=49), cerebral computed tomography (n=31), magnetic resonance imaging and angiography (n=37), and digital subtraction angiography (n=24). All 49 patients experienced a complete ICA occlusion and an ipsilateral recent ischemic infarction. Modified Rankin scale score (mRS) before surgery was 0 to 3 in 20 patients (41%) and 4 to 5 in 29 patients (49%). ICA patency could be restored in 38 patients (78%). The following clinical outcomes were noted: clinical improvement in mRS by at least 1 point in 23 of 49 of patients (47%), no change in 14 of 49 (28%), deterioration in mRS by at least 1 point in 6 of 49 (12%), and death within 30 days in 6 of 49 (12%). A total of 21 patients (43%) experienced perioperative cerebral events (new infarction, new intracranial hemorrhage or enlargement, or hemorrhagic transformation of the preexisting infarction). Univariate analysis showed that clinical improvement correlated significantly with success of recanalization and with early recanalization within 72 hr. Age, gender, and preoperative Rankin stage did not have influence. Clinical deterioration or death was only associated with perioperative cerebral events and seemed to be time-independent. Multivariate analysis did not have enough statistical power to analyze the impact of different risk factors on outcome after urgent revascularization. In patients who undergo surgery after 72 hr from symptom onset, the risk seems to outweigh the benefit.

Letter by Nedeltchev et al Regarding Article, “Short-Term Outcomes After Symptomatic Internal Carotid Artery Occlusion”

To the Editor: In a recent article in Stroke, (1 Burke et al compared the short-term outcome of patients with symptomatic internal carotid artery (ICA) occlusion with that of patients with varying degrees of ICA stenosis. Symptomatic ICA occlusion had worse outcomes than moderate or severe stenosis. Given the poor short-term prognosis, the authors conclude that more aggressive management may be warranted for patients with acute symptomatic ICA occlusion. As pointed out in the article, patients with acute symptomatic ICA occlusion may have …

Endovascular stent-assisted thrombolysis in acute occlusive carotid artery dissection

Internal carotid artery dissection with tandem internal carotid and middle cerebral artery occlusion may be responsible for large cerebral infarction that carries a general poor prognosis. Recanalization of internal carotid artery (ICA) dissection by stent-assisted thrombolysis has been recently proposed. We report two cases of acute symptomatic ICA dissection with tandem occlusion successfully treated with emergent endovascular stent-assisted thrombolysis using new self-expandable intracranial stents. A 37-year-old woman and a 59-year-old man were admitted in our hospital after acute severe symptoms of right-hemispheric stroke with National Institutes of Health Stroke Scale (NIHSS) scores of 15 and 18, respectively. In both cases, magnetic resonance angiography showed tandem occlusion and angiography confirmed tandem occlusion with ICA dissection. An extensive mismatch region was diagnosed by Perfusion-diffusion MRI of the brain within 3 h after symptoms onset. Treatment was initiated 4 h after symptom onset by implantation of self-expandable intracranial stents into the dissected ICA and administration of intra-arterial recombinant tissue plasminogen activator. Recanalization of the ICA and middle cerebral artery (MCA) was accomplished within 6 h after symptoms onset. In both cases, no periprocedural complication was observed and follow-up CT scan showed only a mild brain infarct in the MCA territory. After, respectively, 12 and 10 months follow-up, patients had a favorable outcome with NIHSS 0 and mRS < or = 1. Endovascular stent-assisted thrombolysis appears to be a promising treatment in tandem occlusion due to ICA dissection. Our work underline the potential use of self-expandable intracranial stents in symptomatic acute ICA dissection.

Prognostic Factors for Neurologic Outcome after Endovascular Revascularization of Acute Symptomatic Occlusion of the Internal Carotid Artery

Management of acute symptomatic internal carotid artery (ICA) occlusion remains controversial. We evaluated outcome predictors of a good recovery in patients with acute symptomatic ICA occlusion. We retrospectively evaluated 33 consecutive patients (men/women, 23/10; mean age, 66 years) with: 1) acute symptomatic ICA occlusion within 6 hours of symptom onset or with mismatch of symptoms and an early infarct area, 2) National Institutes of Health Stroke Scale (NIHSS) score of 6 or more, and 3) attempted endovascular revascularization of the occluded ICA. Various single and multiple variable analyses were conducted to assess the association of 14 predictors with short-term (1-month NIHSS) and long-term (1-year modified Rankin Scale [mRS]) outcomes. Successful recanalization (at or more than grade 2 distal residual occlusion) was obtained in 14 (42%) of 33 and good recovery (mRS <or=2) after 1 year in 11 (33%) of 33. Distal residual occlusion (DRO; P=.005), initial NIHSS score (P=.023), and postprocedural thrombolysis in cerebral infarction (P=.027), retrograde ICA filling (P=.036), and ophthalmic collaterals (P=.046) were significant predictors of short-term outcome. DRO (P=.018) and initial NIHSS (P=.033) were significant predictors of long-term outcome on univariable analysis. DRO was the only significant predictor for short-term (P=.026) and long-term outcome (P=.033) on multivariable logistic regression. Active revascularization of acute symptomatic ICA occlusion resulted in good recovery in one third of patients after 1 year. DRO is an independent predictor of a favorable clinical outcome.