Early Spontaneous Recanalization Following Acute Carotid Occlusion

Ultrasonography for the diagnosis of extra-cranial carotid occlusion - diagnostic test accuracy meta-analysis

Background: The correct diagnosis of internal carotid artery (ICA) occlusion is crucial as it limits unnecessary intervention, whereas correct identification of patients with severe ICA stenosis is paramount in decision making and selecting patients who would benefit from intervention. We aimed to evaluate the accuracy of ultrasonography (US) in the diagnosis of ICA occlusion. Methods: We conducted a systematic review in compliance with the Preferred Reporting Items for a Systematic Review and Meta-analysis (PRISMA) of diagnostic test accuracy studies. We interrogated electronic bibliographic sources using a combination of free text and thesaurus terms to identify studies assessing the diagnostic accuracy of US in ICA occlusion. We used a mixed-effects logistic regression bivariate model to estimate summary sensitivity and specificity. We developed hierarchical summary receiver operating characteristic (HSROC) curves. Results: We identified 23 studies reporting a total of 5,675 arteries of which 722 were proven to be occluded by the reference standard. The reference standard was digital subtraction or cerebral angiography in all but two studies, which used surgery to ascertain a carotid occlusion. The pooled estimates for sensitivity and specificity were 0.97 (95% confidence interval (CI) 0.94 to 0.99) and 0.99 (95% CI 0.98 to 1.00), respectively. The diagnostic odds ratio was 3,846.15 (95% CI 1,375.74 to 10,752.65). The positive and negative likelihood ratio were 114.71 (95% CI 58.84 to 223.63) and 0.03 (95% CI 0.01 to 0.06), respectively. Conclusions: US is a reliable and accurate method in diagnosing ICA occlusion. US can be used as a screening tool with cross-sectional imaging being reserved for ambiguous cases.

Acute symptomatic extracranial internal carotid occlusion - natural course and clinical impact

Background: To assess the vascular and clinical course of acute symptomatic extracranial internal carotid artery (ICA) occlusion. Patients and methods: Patients with an acute ischemic event in the anterior circulation and corresponding extracranial ICA occlusion at CT angiography and/or color-coded duplex sonography underwent recurrent duplex follow-up for detection of spontaneous recanalization. Stroke recurrence and functional outcome 4.5 months after the ischemic index event assessed by modified Rankin scale served as secondary outcome parameters. Results: 133 patients (91 men, mean age 62.3 years, SD 10.8) demonstrated symptomatic occlusion of the extracranial ICA with open intracranial ICA and open middle cerebral artery and were followed-up for spontaneous recanalization. Twenty-eight recanalized spontaneously, 25 to high-grade focal stenosis within 12 days, revealing an early cumulative recanalization rate of 23 %. Detection of recanalization was independently associated with de novo dual anti-platelet therapy (adjusted odds ratio [OR], 3.24; 95 % confidence interval [CI], 1.34 to 7.80). Ischemic recurrence occurred in 16 patients, of which 10 deemed to be embolic and 5 hemodynamic. Spontaneous ICA recanalization and an exhausted cerebrovascular reserve in the hemisphere distal to the occluded ICA were both independently associated with the occurrence of a recurrent ischemic event at Cox regression. An increasing NIHSS score at admission, a decreasing middle cerebral artery flow velocity and an ischemic recurrence independently predicted poor outcome (modified Rankin scale 3 to 6) in multivariate analysis. Conclusions: Acute symptomatic extracranial ICA occlusion is an unstable condition with frequent spontaneous recanalization to severe stenosis and early embolic stroke recurrence, demanding appropriate prevention especially in those patients with only mild deficit.

Improving the Prediction of Spontaneous and Post-thrombolytic Recanalization in Ischemic Stroke Patients

BACKGROUND

Endovascular treatment for acute ischemic stroke patients was recently shown to improve recanalization rates and clinical outcome in a well-defined study population. Intravenous thrombolysis (IVT) alone is insufficiently effective to recanalize in certain patients or of little value in others. Accordingly, we aimed at identifying predictors of recanalization in patients treated with or without IVT.

METHODS

In the observational Acute Stroke Registry and Analysis of Lausanne (ASTRAL) registry, we selected those stroke patients (1) with an arterial occlusion on computed tomography angiography (CTA) imaging, (2) who had an arterial patency assessment at 24 hours (CTA/magnetic resonance angiography/transcranial Doppler), and (3) who were treated with IVT or had no revascularization treatment. Based on 2 separate logistic regression analyses, predictors of spontaneous and post-thrombolytic recanalization were generated.

RESULTS

Partial or complete recanalization was achieved in 121 of 210 (58%) thrombolyzed patients. Recanalization was associated with atrial fibrillation (odds ratio , 1.6; 95% confidence interval, 1.2-3.0) and absence of early ischemic changes on CT (1.1, 1.1-1.2) and inversely correlated with the presence of a significant extracranial (EC) stenosis or occlusion (.6, .3-.9). In nonthrombolyzed patients, partial or complete recanalization was significantly less frequent (37%, P < .01). The recanalization was independently associated with a history of hypercholesterolemia (2.6, 1.2-5.6) and the proximal site of the intracranial occlusion (2.5, 1.2-5.4), and inversely correlated with a decreased level of consciousness (.3, .1-.8), and EC (.3, .1-.6) and basilar artery pathology (.1, .0-.6).

CONCLUSIONS

Various clinical findings, cardiovascular risk factors, and arterial pathology on acute CTA-based imaging are moderately associated with spontaneous and post-thrombolytic arterial recanalization at 24 hours. If confirmed in other studies, this information may influence patient selection toward the most appropriate revascularization strategy.

Resolution of carotid stenosis pre-carotid intervention: A case for selective preoperative duplex ultrasound

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This case report draws attention to the benefits of selective preoperative scanning, in sparing patients from unnecessary surgery as a result of finding occlusion or resolution of a previously diagnosed carotid stenosis.

Introduction

Spontaneous resolution of carotid stenosis is a phenomenon that has been described in literature in the past. At present it is not routine practise to scan patients prior to carotid endarterectomy surgery within the UK.

Presentation of case

A 58 year old female presented to hospital with a history of sudden onset headache and left sided weakness. CT head showed findings in keeping with an acute right MCA territory infarct. A duplex ultrasound scan showed echolucent material in the right internal carotid artery forming a greater than 95% stenosis. The scan was unable to visualise the patency of the vessel distally due to the position of the mandible. The patient was provisionally listed for carotid endarterectomy. An MRA was requested prior to surgery to assess the patency of the distal internal carotid artery. The MRA of the carotids showed normal appearance of the common carotid, internal and vertebral arteries with no definite stenosis. A repeat duplex ultrasound confirmed there was no significant stenosis.

Discussion

The finding of complete resolution of stenosis on MRA was an unexpected event. Had the initial duplex imaging allowed visualisation of the distal vessel patency, our patient would have undergone unnecessary carotid surgery with the associated morbidity and mortality.

Conclusion

This case report draws attention to the benefits of selective preoperative scanning, in sparing patients from unnecessary surgery as a result of finding occlusion or resolution of a previously diagnosed carotid stenosis.

Residual high-grade stenosis after recanalization of extracranial carotid occlusion in acute ischemic stroke

BACKGROUND AND PURPOSE

Residual stenosis after recanalization of an acute symptomatic extracranial occlusion of the internal carotid artery (ICA) might be an indication for carotid endarterectomy. We evaluated the proportion of residual high-grade stenosis (≥70%, near occlusions not included) on follow-up imaging in a consecutive series of patients with an acute symptomatic occlusion of the extracranial ICA.

METHODS

We included patients participating in the Dutch Acute Stroke Study (DUST), who had an acute symptomatic occlusion of the extracranial ICA that was diagnosed on computed tomographic angiography within 9 hours after onset of neurological symptoms. Follow-up imaging of the carotid artery had to be available within 7 days after admission.

RESULTS

Of the 1021 patients participating in DUST between May 2009 and May 2013, an acute symptomatic occlusion of the extracranial ICA was found in 126 (12.3%) patients. Follow-up imaging was available in 86 (68.3%) of these patients. At follow-up, a residual stenosis of <30% was found in 15 (17.4%; 95% confidence interval, 10.8-26.9) patients, a 30% to 49% stenosis in 3 (3.5%; 95% confidence interval, 0.8-10.2) patients, a 50% to 69% stenosis in 2 (2.3%; 95% confidence interval, 0.1-8.6) patients, and a ≥70% stenosis in 14 (16.3%; 95% confidence interval, 9.8-25.6) patients. A near or persistent occlusion was present in the remaining 52 (60.5%) patients.

CONCLUSIONS

A residual high-grade stenosis of the extracranial ICA occurs in 1 of 6 patients with a symptomatic occlusion in the acute stage of cerebral ischemia. Because this may have implications for secondary prevention, we recommend follow-up imaging in these patients within a week after the event.

CLINICAL TRIAL REGISTRATION URL

http://www.clinicaltrials.gov. Unique identifier: NCT00880113.

Spontaneous recanalization of the occluded internal carotid artery. A report of two cases

Spontaneous recanalization of the occluded internal carotid artery (ICA) is more frequent than is generally believed. The timing of spontaneous recanalization remains unclear but it may occur as either an early or a late event. The aim of this case report is to emphasize the importance of spontaneous recanalization and its consequences. From September 2008 to November 2010 we prospectively followed patients with old ICA occlusion. The diagnoses of an occlusion were based on duplex scan findings and were confirmed by CT angiography and digital subtraction angiography (DSA). ICA occlusions secondary to dissection, inflammatory process, like fibromuscular dysplasia, previous stenting or endarterectomy and trauma, were excluded from the study. All patients had a scheduled carotid duplex scan every six months. Overall 65 patients were enrolled. Two patients showed evidence of spontaneous recanalization. A 55-year-old man with a known history of transient ischemic attack had occlusion in the left side ICA. He presented with another TIA eight months later. Investigations showed evidence of rcanalization of occluded ICA. This artery underwent uneventful stenting. In another patient recanalization was heralded by global aphasia and right side hemiplegia. He was a 70-year-old man with a history of recurrent TIA. Carotid duplex scan and DSA showed recanalization of the occluded left ICA accompanied by occlusion of the ipsilateral middle cerebral artery. He remained profoundly disabled with severe neurological deficits. In conclusion, spontaneous recanalization of the occluded internal carotid artery is a potentially complicated event that may lead to severe neurological disability.

Emergent endovascular recanalization for cervical internal carotid artery occlusion in patients presenting with acute stroke

BACKGROUND

Acute proximal (cervical) internal carotid artery (ICA) occlusion may cause ischemia of an entire hemisphere or no ischemia at all, depending on the presence of intracranial collaterals.

OBJECTIVE

To retrospectively analyze the clinical results for emergent endovascular carotid recanalization in patients with acute proximal (cervical) ICA occlusion and to assess predictors of recanalization and clinical, neurological, and functional outcome.

METHODS

Emergent endovascular revascularization was attempted in 22 patients presenting with acute stroke secondary to complete cervical ICA occlusion. Patients with pseudo-occlusion were excluded. Recanalization was assessed with the Thrombolysis in Myocardial Ischemia (TIMI) system: grade 0 (no flow) to grade 3 (normal flow).

RESULTS

The median age of the patients was 65 years; mean admission National Institutes of Health Stroke Scale (NIHSS) score was 14. Recanalization (TIMI grade 2/3) occurred in 17 patients (77.3%). Ten patients (45.5%) demonstrated significant clinical improvement during hospitalization (NIHSS improved ≥4 points). Fifty percent of patients had good outcomes (modified Rankin Scale ≤2) after a median follow-up of 3 months. Patient age <70 years and successful recanalization (TIMI grade 2/3) predicted a good outcome (P ≤ .01). Presence of atrial fibrillation, admission NIHSS score ≥20, and complete ICA occlusion at all levels (cervical, petrocavernous, and intracranial) were associated with poor outcomes (P ≤ .05). Patients with complete cervical ICA occlusion but partial distal preservation of the vessel were most likely to benefit from the intervention (recanalization in 88.2%; good outcome in 64.7%).

CONCLUSION

Attempts at emergent endovascular carotid recanalization for acute stroke are encouraged, particularly in younger patients with partial distal preservation of the ICA.

Spontaneous recanalization of complete internal carotid artery: a clinical reminder

Spontaneous recanalization of atherothrombotic extracranial cerebral arteries is rare vis-à-vis recanalization of intracranial vessels. The time course is unknown. The question is the advisability and timing of surgery in a recanalized vessel. We describe a patient with spontaneous recanalization of a totally occluded left Internal Carotid Artery (ICA) who was monitored with periodic imaging and in time had partial recanalization of the ICA. We believe patients with total ICA occlusion with return of function should be followed up with periodic carotid ultrasound, Magnetic Resonance Angiography (MRA) or CT angiography, and when appropriate, be candidates for carotid vascular interventions.

Spontaneous recanalization of an occluded internal carotid artery

Recanalization after extracranial internal carotid artery (ICA) occlusion is a rare phenomenon and the natural history of the disease is largely unknown. There have been few cases reported in the published data, including early recanalization after a cerebrovascular accident (CVA). We report a case of a 74-year-old man who presented with a CVA and a history of multiple CVAs in the past, the last episode being a year ago. Multiple imaging modalities, including duplex scans, computerized tomographic angiograms, and fluoroscopy-guided angiogram of bilateral carotid arteries, showed occlusion of the left ICA in the past. The duplex scan performed 8 months later demonstrated late spontaneous recanalization of the occluded left ICA. The patient underwent successful carotid endarterectomy. The pathophysiology, natural history, and possible surveillance strategy are discussed in this case report.

Ultrasonographic and perioperative macroscopic findings in acute carotid artery occlusion

BACKGROUND AND PURPOSE

acute ischemic stroke (AIS) may occur both in the acute and chronic internal carotid artery occlusion (ICAo). Thus, it is important to assess the ICAo character when considering the recanalization method. The aim was to assess the agreement between the ultrasonographic (US) and perioperative macroscopic (PM) finding in AIS patients with acute ICAo, undergoing an emergent carotid endarterectomy.

METHODS

in a retrospective, hospital-based study, the set consisted of 47 patients (36 males; age 49-79, mean 63.7 ± 8.5 years). ICAo character was classified as an acute thromboembolus either isolated or in combination with atherosclerotic plaque using the US (B-mode) and the PM evaluation. Cohen's Kappa and AC(1) coefficient were applied to assess the methods agreement.

RESULTS

an acute ICAo character diagnosed by US was confirmed by the PM evaluation in all cases. US and PM findings were consistent in 41 cases. The agreement between both methods in the classification of acute ICAo was 87.2% [95% confidence interval (CI): 77.7-96.8%], κ= .589 (95% CI: .293-.885) (P < .0001), AC(1) = .815.

CONCLUSIONS

US is a reliable method in the diagnostics of the acute character of ICAo and it has a good agreement with PM finding regarding a differentiation of atherosclerotic plaque and fresh thromboembolus.