Hyperperfusion Syndrome Research Articles

CAS 後過灌流症候群の発症予測に関する研究

CAS 後過灌流症候群の発症予測に関する研究

頚動脈狭窄症の周術期管理におけるarterial spin labeling（ASL）法の有用性

Cerebral hyperperfusion syndrome is a rare but devastating complication after carotid endarterectomy (CEA) or carotid artery stenting (CAS). We evaluated whether arterial spin labeling (ASL) can predict cerebral hyperperfusion syndrome after carotid revascularization.Here we reviewed 10 cases of carotid artery stenosis treated with CEA or CAS. Five cases presented with hyperperfusion phenomenon on single photon emission computed tomography. In four of these five cases, ASL was found to be useful in predicting hyperperfusion phenomenon. There were no cases of intracerebral hemorrhage.ASL is noninvasive and useful for understanding cerebral perfusion during the perioperative period that requires several minutes on routine MRI. However, there are some limitations. To avoid misinterpretation of data, it is important that clinicians have a good understanding of the basic principles of ASL.

Current status of revascularization surgery for Moyamoya disease: special consideration for its 'internal carotid-external carotid (IC-EC) conversion' as the physiological reorganization system.

Moyamoya disease is a chronic cerebrovascular disease with unknown etiology, which is characterized by bilateral steno-occlusive changes at the terminal portion of the internal carotid artery and an abnormal vascular network formation at the base of the brain. Moyamoya disease is known to have unique and dynamic nature to convert the vascular supply for the brain from internal carotid (IC) system to the external carotid (EC) system, as indicated by Suzuki's angiographic staging established in 1969. Insufficiency of this 'IC-EC conversion system' may result in cerebral ischemia, as well as in intracranial hemorrhage from inadequate collateral vascular network, both of which represent the clinical presentation of moyamoya disease. Therefore, surgical revascularization by extracranial-intracranial bypass is the preferred procedure for moyamoya disease to complement 'IC-EC conversion' and thus to avoid cerebral infarction and/or intracranial hemorrhage. Long-term outcome of revascularization surgery for moyamoya disease is favorable, but rapid increase in cerebral blood flow on the affected hemisphere could temporarily cause unfavorable phenomenon such as cerebral hyperperfusion syndrome. We would review the current status of revascularization surgery for moyamoya disease based on its basic pathology, and sought to discuss the significance of measuring cerebral blood flow in the acute stage and intensive perioperative management.

A Study about the changs of cerebral hemodynamics in carotid endarterectomy

Objective To study how to prevent cerebral ischemia and hyperperfusion syndrome during carotid endarterectomy (CEA).Methods Twenty-ninth cases of patients undergoing CEA (35 procedures in total) with carotid artery stenosis were divided into bilateral (group A) and unilateral (group B) stenosis groups.During CEA,the regulation of blood pressure was according to the changes of the ipsilateral middle cerebral artery mean flow velocity (MCA Vm) detected by transcranial Doppler (TCD):if the MCA Vm after carotid artery occlusion was lower than 70％ of that before occlusion,the blood pressure should be increased; and if the MCA Vm after release cross was higher than 100％ of that before carotid artery occlusion,the blood pressure should be decreased.All cases in the study were underwent transcranial Doppler,color Doppler flow imaging,CT angiography,CT perfusion imaging,Magnetic resonance imaging,and/or digital subtraction angiography before and after surgery.Results (1) In the two groups:the MCA Vm of the intraoperation side before carotid artery occlusion was decreased as compared with that before anesthesia (P =0.000).After carotid artery occlusion,the MCA Vm was decreased slightly as compared with that before occlusion (P ＞ 0.05),and the blood pressure was increased (23.76 ±9.15)％ (P =0.000) ; The MCA Vm after release cross was higher than that before occlusion(P =0.000),the blood pressure was decreased (6.70 ±6.89)％ (P =0.000).(2) Between the two groups:After carotid artery occlusion,the MCA Vm of the intraoperation side in group B was decreased than that in group A (P ＜ 0.05).The enhance rate of the blood pressure was higher than that in group A(P ＜0.01).After release cross,the reduce rate of the blood pressure in group B was lower than that group A (P ＜ 0.05).The MCA Vm between the two groups had no statistic difference (P ＞ 0.05).(3) After surgery,the cerebral perfusion of all patients of the intraoperation side was improved versus that before surgery.Conclusion During CEA,TCD could real-time monitor the changes of cerebral hemodynamics,evaluate the cerebral perfusion,guide the to regulate the blood pressure timely,so as to improve the success rate of surgery significantly. Key words: Ultrasonography, Doppler, transcranial ; Carotid stenosis ; Carotid endarterectomy; Cerebral hemodynamics

Hyperperfusion Syndrome After Stenting for Intracranial Artery Stenosis.

Hyperperfusion syndrome (HPS) is a rare but potentially devastating postoperative complication developing after endarterectomy and carotid stenting. Limited information is available about this complication. The aim of this study was to assess the incidence of HPS and risk factors leading to its development. We retrospectively reviewed 178 consecutive cases of patients who underwent stenting of intracranial artery revascularization. We analyzed the association between HPS and patient's age, collateral vascular supply of the lesion, the interval between operation and the last occurrence of ischemic symptom, adequacy of blood pressure control after the operation, and other risk factors such as diabetes, smoking, hypertension, and gender. Of 178 included patients, we found HPS in six cases (3.4%). Failure to strictly control postoperative blood pressure, a less than 3-week long interval between operation and the last occurrence of ischemic symptom, and poor collateral circulation were significantly associated with the development of HPS. The aforementioned factors are predictors for HPS. We argue that nitroprusside should not be used to control blood pressure after the operation because its use permits considerable blood pressure fluctuations.

Treatment Strategy for Bilateral Carotid Stenosis: 2 Cases of Carotid Endarterectomy for the Symptomatic Side Followed by Carotid Stenting

Since the introduction of carotid stenting (CAS), a combined treatment for bilateral lesions using carotid endarterectomy (CEA) and CAS has been developed. However, there has been only 1 report about CEA then CAS. Herein we describe 2 patients with bilateral severe carotid stenosis who were treated by CEA for the symptomatic side and CAS for the contralateral asymptomatic side. A 71-year-old man underwent CEA for the symptomatic side. Although the patient suffered hyperperfusion syndrome after CEA, he recovered fully after 3 weeks of rehabilitation. Two months later, CAS was performed for the asymptomatic side, and he was discharged with no deficit. A 67-year-old man underwent CEA for the symptomatic side. The patient developed no postoperative neurologic deficits except for hoarseness. Four weeks later, CAS was performed for the contralateral asymptomatic side. After the procedure, however, severe hypotension occurred, and treatment by continuous injection of catecholamine was necessary to maintain systematic blood pressure. The patient was ultimately discharged with no deficit. The combined therapy of CAS for the asymptomatic side and then CEA for the symptomatic side has been recommended by several authors. However, one of the problems of this strategy is the higher incidence of postprocedural hemodynamic complications, and hypotension after CAS may be dangerous for the symptomatic hemisphere. We suggest a combined therapy using CEA for the symptomatic side and then CAS for the asymptomatic side can be 1 beneficial treatment option for patients with bilateral carotid stenosis without coronary artery disease.

Hyperperfusion syndrome with a fatal intra-cerebral hemorrhage after carotid endarterectomy

IntroductionLe syndrome d’hyperperfusion cerebrale avec hemorragie intracrânienne, apres endarteriectomie ou stenting carotidien, est associe a une morbi-mortalite importante [1, 2]. La physiopathologie de ce syndrome reste obscure [3]. Parmi les hypotheses avancees, la perte d’autoregulation des capillaires cerebraux liee a l’ischemie chronique est le mecanisme le plus souvent retenu. Mais les modifications hemodynamiques survenant apres la revascularisation carotidienne [...]

Quantitative analysis of early postoperative cerebral blood flow contributes to the prediction and diagnosis of cerebral hyperperfusion syndrome after revascularization surgery for moyamoya disease

Objective:Cerebral hyperperfusion syndrome (HPS) is a potential complication of extracranial–intracranial (EC–IC) bypass for moyamoya disease; however, the pathological threshold of the early cerebral blood flow (CBF) increases after EC–IC bypass has yet to be determined. The purpose of this study is to evaluate the predictive and diagnostic values of early quantitative CBF analysis for the detection of HPS after EC–IC bypass for moyamoya disease.Methods:We quantitatively evaluated regional CBF at the site of the anastomosis in 23 patients with moyamoya disease aged between 18 and 66 years (mean, 39·6) before and 1 day after superficial temporal artery-middle cerebral artery anastomosis by an auto-radiographic method using N-isopropyl-p-[123I]iodoamphetamine single-photon emission computed tomography.Results:Regional CBF 1 day after surgery was significantly higher in patients with HPS (n = 5; mean, 54·6 ml/100 g/minutes) than in patients without HPS (n = 18; mean, 40·5 ml/100 g/minutes) (P = 0·038). The postoperative/preoperative CBF ratio was significantly higher in patients with HPS (1·84) than in patients without HPS (1·34) (P = 0·044). Multivariate analyses showed that the regional CBF value 1 day after surgery (P = 0·036) and operating on the left hemisphere (P = 0·026) significantly correlated with HPS. All patients with HPS developed symptoms and/or intracerebral hemorrhage more than 2 days after EC–IC bypass. Receiver operating characteristic analysis indicated that the cutoff value of pathological postoperative CBF increase was 46·1 ml/100 g/minutes (sensitivity = 80%, specificity = 77·8%, AUC value = 0·81).Conclusion:Quantitative analysis of early postoperative CBF is useful for predicting and diagnosing HPS after revascularization surgery for moyamoya disease.

E-024 A Single-center Experience of Carotid Artery Stenting in Patients with Carotid Stenosis

BackgroundCarotid artery stenting (CAS) has emerged as a potential alternative to endarterectomy and its clinical practise dramatically increased in many parts of the world. This study aims to determine the...

Review of Post-Carotid Endarterectomy Complications

Atherosclerotic carotid artery stenosis is one of the most common causes of stroke worldwide. Carotid revascularization using Carotid Endarterectomy (CEA) may play an important role in reducing the stroke prevalence in selected patients. Post-CEA complications of significant concern include cerebral hyperperfusion syndrome, ischemic stroke and cranial nerve injury, perioperative myocardial infarction, unstable angina, respiratory problems, renal failure, wound complications, and postoperative hyper- or hypotension. With regards to CEA complications, the individual risk assessment plays an inevitable role in reducing the negative outcomes and increasing the procedure efficacy. In this review, we studied CEA complications by reviewing the previously published literature. In addition to its benefits, CEA has its own complications, but at a lower severity. Reducing the incidence of post-CEA complications is crucial, especially in the patients with a less remarkable margin of benefit in stroke prevention. Despite its complications, CEA remains the gold standard for treating carotid stenosis in selected symptomatic and asymptomatic patients. Accurate perioperative diagnosis and evaluation may help us develop a practical approach to more a beneficial and accurate surgical strategy.

Disease-specific guidelines for reporting adverse events for peripheral vascular medical devices

Disease-specific guidelines for reporting adverse events for peripheral vascular medical devices

Influence of the Hostile Neck on Restenosis after Carotid Stenting

Carotid artery stenting (CAS) for carotid stenosis is favored over carotid endarterectomy (CEA) in patients with a hostile neck from prior CEA or cervical irradiation (XRT). However, the restenosis rate after CAS in patients with hostile necks is variable in the literature. The objective of this study was to quantify differences in the in-stent restenosis (ISR)/occlusion and reintervention rates after CAS in patients with and without a hostile neck. Here we hypothesize that patients with hostile necks have an increased ISR, and that this increase may add morbidity to these patients. All patients undergoing CAS from 2007 to 2013 for carotid artery stenosis with follow-up imaging at our institution were queried from our carotid database (n = 236). Patients with hostile necks, including both CAS after prior CEA (n = 65) and prior XRT (n = 37), were compared with patients who underwent CAS for other reasons including both anatomical (n = 46) and medical comorbidities (n = 88). The primary end points were ISR, repeat intervention, and stent occlusion. Secondary end points of the study were stroke/myocardial infarction (MI)/death at 30 days, perioperative cardiovascular accident, transient ischemic attack, MI, groin access complications, hyperperfusion syndrome, and periprocedural hypotension or bradycardia. Despite the hostile neck cohort being younger and having lower incidence of chronic obstructive pulmonary disease, coronary artery disease, and renal insufficiency, they had a greater incidence of ISR (11% vs. 4%; P = .03) and required more reinterventions (8% vs. 2%; P = .04). Stent occlusion and periprocedural morbidity/mortality were not different between groups. Patients with hostile necks have increased risk of restenosis and need for reinterventions after CAS compared with patients without a hostile neck. However, they do not appear to have higher rates of stent occlusion or per-procedural events.

Postendarterectomy Cerebral Hyperperfusion Syndrome: The Etiological Significance of "Cerebral Reserve".

Postoperative cerebral hyperperfusion syndrome (CHS) in patients undergoing carotid intervention is thought to be related to the absence of cerebral reserve. Although hyperperfusion syndrome is rare, severe postoperative headache is common and is considered to be a prodromal sign. Cerebral reserve is measured by studying the response of cerebral vessels to a vasodilator such as hypercarbia. We produced hypercarbia by holding respiration for 60 seconds during carotid endarterectomy. We attempted to evaluate the relationship between intraoperatively evaluated cerebral reserve and the development of postoperative headache which was severe enough to require the patient to take an over the counter analgesic (e.g., ibuprofen, acetaminophen, aspirin). Internal carotid artery flow 1 (F1), Pco 2, and blood pressure 1 (BP1) were recorded before and after (F2, Pco 2, and BP2) 60 seconds of apnea. An increase in flow of > 20% was considered indicative of adequate cerebral reserve. Patients were evaluated before discharge and with follow-up calls at 2 to 5 days postdischarge. Fisher exact test was used to evaluate categorical predictors. Unpaired t test was used to compare continuous variables. Results were considered significant when p < 0.05. A total of 30 nonconsecutive patients were evaluated prospectively. Of the 30 patients, 4 (Group I) developed severe postoperative headache; 26 did not (Group II). Demographics were similar in both the groups. Three patients in Group I and 16 patients in Group II had > 20% increase in flow (p = 0.6315). Pco 2 rose in both groups and BP2 was unchanged from BP1 in both groups. Lack of cerebral reserve does not appear to be related to the development of severe postoperative headache.

Bilateral reperfusion injury after carotid endarterectomy with contralateral carotid occlusion.

Cerebral hyperperfusion syndrome represents a clinical spectrum characterized by severe unilateral headache, acute changes in mental status, vomiting, seizures, focal neurologic deficits, and, in its most severe form, intracranial hemorrhage. With the exception of one early case report, reperfusion injury to the brain following carotid endarterectomy has been reported only ipsilateral to the side of surgery. We report the unique case of a patient with symptomatic severe right internal carotid artery stenosis and contralateral carotid occlusion who underwent carotid endarterectomy complicated by cerebral hyperperfusion syndrome and associated bilateral intracranial hemorrhage.

De Novo Ivy Sign Indicates Postoperative Hyperperfusion in Moyamoya Disease

The ivy sign on fluid-attenuated inversion recovery MRI is a specific finding in moyamoya disease (MMD). This sign indicates decreased cerebral perfusion, dilated pial vasculature, and slow leptomeningeal collateral flow. This study aimed to clarify the characteristics of perioperative changes in the ivy sign in relation to cerebral hyperperfusion, which frequently occurs in MMD of unknown pathogenesis. This prospective study included patients with MMD who underwent superior temporal artery-middle cerebral artery single bypass. Fluid-attenuated inversion recovery MRI was performed to evaluate the appearance of the ivy sign in the ipsilateral hemisphere preoperatively and on postoperative days 2 and 30. The ivy sign was assessed in combination with perioperative symptoms and cerebral hemodynamics using single-photon emission computed tomography. Of 42 consecutive patients (55 sides) who underwent bypass surgery, 32 (58.2%) showed an increase in the ivy sign (de novo ivy sign) on postoperative day 2; this had disappeared by day 30. Interestingly, these 32 patients had a significantly higher incidence of hyperperfusion on single-photon emission computed tomography and hyperperfusion syndrome, and there was no correlation between the de novo ivy sign and a preoperative ivy sign or the preoperative cerebral hemodynamics. In multivariate analysis, a de novo ivy sign was significantly correlated with postoperative hyperperfusion. In MMD, a de novo ivy sign could indicate postoperative hyperperfusion after bypass, which is not always correlated with preoperative hemodynamic impairment. Additional factors other than preoperative cerebral hemodynamics might be involved in postoperative hyperperfusion in MMD.

Predictors and consequences of unplanned hospital readmission within 30 days of carotid endarterectomy

In the United States, vascular surgeons frequently perform carotid endarterectomy (CEA). Given the resource burden of unplanned readmission (URA), we sought to identify the predictors and consequences of URA after this common vascular surgery procedure to identify potential points of intervention. Using a prospective single-institution database, we retrospectively identified consecutive patients undergoing CEA (2001-2011). Demographic and perioperative factors were prospectively collected. The primary end point was 30-day postdischarge URA after CEA. The secondary end point was 1-year survival. We performed a univariable analysis for URA followed by a multivariable Cox model. A Kaplan-Meier analysis was performed for 1-year survival. During the study period, 840 patients underwent 897 CEAs. The 30-day postdischarge overall readmission rate and URA rate were 8.6% and 6.5%, respectively. Most URA patients (n= 42; 73.4%) were readmitted for a CEA-related reason (headache, cardiac, hypertension, surgical site infection, bleeding/hematoma, stroke/transient ischemic attack, dysphagia, or hyperperfusion syndrome). Seventeen patients (29.3%) had more than one reason for URA. Median time to URA was 4days (interquartile range, 1-9days). Postoperative length of stay, indication for CEA, and discharge destination were not associated with URA. In multivariable analysis, in-hospital occurrence of congestive heart failure (hazard ratio [HR], 15.1; 95% confidence interval [CI], 4.7-48.8; P< .001), stroke (HR, 5.0; 95% CI, 1.8-14.0; P< .001), bleeding/hematoma (HR, 3.1; 95% CI, 1.4-6.9; P= .003), and prior coronary artery bypass grafting (HR, 2.0; 95% CI, 1.2-3.5; P= .01) were significantly associated with URA. Patients in the URA group also had decreased survival during 1year (91% vs 96%; P= .01, log-rank). The 30-day URA rate after CEA is low (6.5%). Prior coronary artery bypass grafting and in-hospital postoperative occurrence of stroke, bleeding/hematoma, and congestive heart failure identify those at increased risk of URA, and URA signals increased long-term risk of postoperative mortality.

Emergency carotid artery stenting in patients with acute ischemic stroke due to occlusion or stenosis of the proximal internal carotid artery: a single-center experience

BackgroundThe feasibility, safety and effectiveness of emergency carotid artery stenting (eCAS) in patients with acute ischemic stroke (AIS) due to proximal internal carotid artery (ICA) stenosis or occlusion are still...

Treatment outcomes of carotid artery stenting with two types of distal protection filter device

PurposePreventing cerebral embolism from debris produced during carotid artery stenting (CAS) is important. This study compared the treatment outcomes of CAS using two types of filter-based embolic protection devices currently in use in Japan.Materials and methodsWe assessed 121 consecutive cases of CAS performed with FilterWire EZ™ between July 2010 and November 2012 and 37 consecutive cases of CAS performed with the Spider FX™ between November 2012 and June 2013. A Carotid Wallstent™ was used in all cases. The incidence of positive lesions on diffusion-weighted magnetic resonance imaging (DWI) and stroke were compared between the groups.ResultsPostoperative DWI-positive lesions were observed in 38 (31.4%) and 14 (37.8%) patients in the FilterWire and Spider groups, respectively. In the FilterWire group, complications were transient ischemic attacks in 3 (2.5%) patients, cerebral infarction in 2 (1.7%) patients (1 patient each with minor and major stroke), and cerebral hemorrhage due to hyperperfusion syndrome in 1 (0.8%) patient. In the Spider group, except for cerebral infarction (minor stroke) in 1 (2.7%) patient, no complications were observed. No significant differences were observed in the incidence of complications between the groups.ConclusionFilterWire EZ and Spider FX are comparable in terms of treatment outcome.

Perioperative Management of Carotid Endarterectomy: A Survey of Clinicians’ Backgrounds and Practices

To examine current trends in anesthetic practice for management of carotid endarterectomy (CEA) and how practice may differ by groups of practitioners. An online survey was sent to the Society of Cardiovascular Anesthesiologists and Society of Neuroscience, Anesthesiology, and Critical Care e-mail list servers. Responses were voluntary. Academic medical centers and community-based hospitals providing perioperative care for a CEA in the United States and abroad. Anesthesiologists who provide perioperative care for patients undergoing a CEA. None Of 664 responders (13% response rate), most (66%) had subspecialty training in cardiovascular anesthesiology, had been in practice more than 10 years (68%), and practiced in the United States (US, 81%). About 75% of responders considered general anesthesia as a preferable technique for CA, and about 89% of responders provided it in real life, independent of subspecialty training. The most preferable intraoperative neuromonitoring was cerebral oximetry (28%), followed by EEG (24%), and having an awake patient (23%). Neuroprotection was not considered by 33% of responders, and upon conclusion of a case, 59% preferred an awake patient for extubation, while 15% preferred a deep extubation. Neuroanesthesiologists and non-US responders more often risk stratify patients for perioperative cerebral hyperperfusion syndrome, compared with cardiac anesthesiologists and US responders (p=0.004 and p<0.005, respectively). Additionally, reported management strategies vary substantially from anesthetic practice 20 years ago. Although there are areas of perioperative management in which there seems to be agreement for the CEA, there are also areas of divergent practice that could represent potential for improvement in overall outcomes. There are many potential reasons to explain divergence in practice by location or subspecialty training, but it remains unclear what the "best practice" may be. Future studies examining outcomes after carotid endarterectomy should include perioperative anesthetic management strategies to help delineate "best practice."

Abstract W P227: Cerebral Hyperperfusion Syndrome after Intravenous Thrombolysis for Acute Ischemic Stroke

Background: Cerebral hyperperfusion syndrome (CHS) is a recognized complication after surgical revascularization of a chronically atherosclerotic artery. However, this phenomenon is unexpected when an acutely occluded artery is recanalized by IV-TPA for acute ischemic stroke (AIS).In patients with discrepant neuroimaging and clinical findings, our multimodal evaluations revealed CHS in a series of 7 patientsmafter IV- TPA therapy. Methods: Patients in whom the occluded ICA or MCA in pre-TPA CT-angiogram (CTA) showed recanalization in the day-2 CTA, were observed for any new unexpected neuropsychiatric symptoms/signs. If these were present they underwent multimodal evaluation including serial transcranial Doppler (TCD), quantitative electroencephalography (QEEG) and HMPAO-SPECT. Patients with considerable mismatch between clinical and neuroimaging findings were also included. CHS was deemed to have occurred if the unexpected neuropsychiatric signs corresponded with TCD flow velocity &gt;100% of the contralateral vessel, EEG showed abnormal activity and HMPAO-SPECT scan showed markedly increased cerebral perfusion compared to the contralateral side. Results: Out of 155 patients treated with IV-TPA, 7 (4.5%) patients fulfilled our definition of CHS. All 7 patients developed the symptoms 2-3 days after IV-TPA. Abnormalities on TCD, QEEG and HMPAO-SPECT were observed in all patients. The unexpected symptoms included generalized headache (4 cases), unexplained persistent drowsiness (3 cases), visual neglect (2 cases), aphasia (2 cases) and severe suicidal thoughts despite complete neurological recovery (1 case). All cases had hypertension prior to the index stroke. Upright posture, fluid restriction and aggressive blood pressure control resulted in rapid resolution of abnormal features in all cases within a week. All patients achieved modified Rankin score 0-1 with no intracranial hemorrhage. Conclusion: CHS after intravenous thrombolysis in acute ischemic stroke should be suspected in patients that achieve arterial recanalization with unexplained new neuropsychiatric manifestations. Early diagnosis and appropriate management might prevent hemorrhage and achieve good functional outcomes.