Hypertension and the post-carotid endarterectomy cerebral hyperperfusion syndrome

Incidence and risk factors of cerebral hyper-perfusion syndrome like symptoms after resection of carotid body tumours

INTRODUCTION

Cerebral hyper-perfusion syndrome (CHS) is a rare but severe complication after surgery of carotid artery related disease (with a varied incidence range of 0-25.7 %), while its association with carotid body tumour (CBT) surgery is unknown. This study aimed to investigate the incidence and risk factors of CHS-like symptoms after resection of CBTs.

METHODS

This retrospective study included 152 CBT patients (165 operated tumours) who received surgery at Peking Union Medical College Hospital from March 2013 to December 2021 and had fully-available clinical records. Surgeries were performed by the several operation teams (around 4-5 teams during the study period) from the department of vascular surgery, of which the team leaders were all senior vascular surgeons who had full experience on CBT surgery. CHS-like symptom was determined based on clinical manifestation and its risk factors were identified by univariate and multivariate regression analyses.

RESULTS

The mean age of this cohort was 44.2 ± 10.9 years and female patients represented 67.1 % (102/152). There were 13 (13/152, 10.5 %) cases receiving bilateral CBT resections, generating a total of 165 operated tumours. The median maximum diameter of the tumours was 3.5 cm (IQR: 2.5-4.8 cm), with 37 (22.4 %), 40 (24.2 %) and 88 (53.3 %) lesions being classified as Shamblin I, II and III, respectively. All CBTs were completely resected under general anaesthesia, with 51 patients undergoing balloon occlusion tests (51/152, 33.6 %) preoperatively and no preoperative embolization was performed. During surgery, 34 cases (34/165, 20.6 %) underwent intervention for internal carotid artery (ICA) and 43 cases (43/165, 26.1 %) underwent external carotid artery ligation. Among the 165 operations, 43 cases developed CHS-like symptoms after surgery (26.1 %, 43/165), of which 26 cases received dehydrant therapy due to severe symptoms (60.5 %, 26/43) and most cases developed symptoms within 48 h after surgery (90.7 %,39/43). Univariate analysis revealed that occurrence of CHS-like symptoms is significantly related with elevated post-operation immediate heart rate (HR) (P = 0.006), post-operation day 1 morning HR (P = 0.004), ICA intervention (P = 0.002) and postoperative new-onset hypertension (P = 0.02). Furthermore, ICA intervention (P = 0.008) and new-onset hypertension (P = 0.017) remained the independent risk factors for development of CHS-like symptoms in multivariate regression analysis.

CONCLUSION

CBT excision is related to a significant incidence of postoperative CHS-like symptoms, of which intraoperative ICA intervention and post-operative new-onset hypertension are the independent risk factors, thus more attention and closer monitoring should be given on such patients so as to prevent life-threatening CHS-related cerebral complications.

Surgical Management of Severe Bilateral Carotid Artery Stenosis With Combined Carotid Endarterectomy and Stenting: Implications for Craniofacial and Cerebrovascular Health

OBJECTIVE

This study aimed to evaluate the clinical outcomes of a combined surgical approach involving carotid endarterectomy (CEA) and carotid artery stenting (CAS) for the management of patients with severe bilateral carotid atherosclerotic stenosis.

METHODS

A retrospective analysis was conducted on the clinical data of 19 patients diagnosed with severe bilateral carotid artery stenosis who were hospitalized between June 2019 and January 2022. The efficacy of the combined CEA and CAS approach was analyzed.

RESULTS

Postoperative imaging confirmed complete resolution of stenosis, restored lumen patency, and substantial improvement in intracranial hypoperfusion across 38 stenotic sites in the 19 patients. No serious complications were observed during the perioperative period. At the 3-month follow-up, none of the patients experienced cerebrovascular events, and symptoms of preoperative cerebral ischemia revealed varying degrees of improvement. The modified Rankin Scale (mRS) score was ≤2 in all patients, with a mean score of 1.52±0.18. Over a follow-up period extending up to 48 months, no recurrence of stroke or severe complications was reported.

CONCLUSION

The choice of surgical intervention for patients with severe bilateral carotid artery stenosis should be tailored to the clinical profile of each patient. The combined approach of CEA and CAS integrates the advantages of both techniques, reduces the risk of postoperative complications, and enhances the range of therapeutic options available for this population.

Seizures Following Carotid Endarterectomy: A Comprehensive Meta-Analysis of 69,479 Patients and Evidence-Based Recommendations for Perioperative Care

Background: Seizures are a rare but potentially serious complication following carotid endarterectomy (CEA). Understanding their prevalence and associated factors is crucial for optimizing perioperative care and improving patient outcomes. This meta-analysis aimed to estimate the pooled prevalence of seizures following CEA and explore clinical and procedural factors contributing to their occurrence. Methods: We conducted a systematic review and meta-analysis of studies reporting on seizures following CEA. A systematic search of PubMed, Embase, and Cochrane CENTRAL databases was performed, following PRISMA and MOOSE guidelines. Random-effects meta-analysis was used to calculate the pooled prevalence of postoperative seizures. Heterogeneity was assessed using the I2 statistic. A total of 20 studies, encompassing 69,479 patients, were included. Results: The overall pooled prevalence of seizures following CEA was 1% (95% CI: 0-2%; p < 0.001), with significant heterogeneity (I2 = 93.52%). Prospective studies reported a higher pooled prevalence (2%, 95% CI 0-4%; I2 = 76.34%) compared to retrospective studies (0%, 95% CI 0-1%; I2 = 91.51%). Male predominance was noted among patients who experienced seizures, and hypertension was the most common comorbidity. Cerebral hyperperfusion syndrome was identified as a key contributing factor to postoperative seizures. Data on long-term outcomes, including the development of epilepsy, were insufficient for further analysis. The methodological quality of the included studies varied, with most studies demonstrating a moderate risk of bias. Conclusions: Seizures occur in approximately 1% of patients following CEA, with higher rates observed in prospective studies. Cerebral hyperperfusion syndrome is an important contributor to this rare complication. We provide evidence-based specific recommendations for seizure management and introduce the SMART-CEA Checklist, a practical framework to guide perioperative care and reduce complications. Future research should focus on long-term outcomes, including epilepsy, and incorporate standardized methodologies to improve data reliability and guide clinical practice.

Reversible cerebral vasoconstriction syndrome following carotid artery revascularization: About three case reports and review of literature

Complication after carotid artery revascularization is mainly represented by stroke. Reversible cerebral vasoconstriction syndrome triggering by carotid artery revascularization is exceptional but it is an unrecognized aetiology of stroke. It could be associated with brain edema and henceforth, a posterior reversible encephalopathy syndrome can be confused with post-carotid artery revascularization cerebral hyperperfusion syndrome. We reported three cases about reversible cerebral vasoconstriction syndrome following revascularization therapy whose one had also a posterior reversible encephalopathy syndrome. This complication occurred within two weeks after carotid artery revascularization. All took nimodipine and all had a functional improvement at 3-months follow-up. Reversible cerebral vasoconstriction syndrome with posterior reversible encephalopathy syndrome after carotid artery revascularization may mimic cerebral hyperperfusion syndrome. After a comprehensive review, nineteen cases of reversible cerebral vasoconstriction syndrome post-carotid artery revascularization have been reported in the literature mainly after symptoms. It occurs mainly in women around sixty years of age. The onset is expected four days after revascularization.

A computational method to predict cerebral perfusion flow after endovascular treatment based on invasive pressure and resistance

BACKGROUND AND OBJECTIVE

Predicting post-operative flow is essential for assessing the risk of adverse events in cerebrovascular stenosis patients following endovascular treatment (EVT). This study aimed to evaluate the accuracy of the CFD simulation model in predicting post-operative velocity, flow and pressure distal to a stenosis, based on cerebrovascular microcirculatory resistance.

METHODS

The patient-specific models of the extracranial and intracranial arteries were reconstructed. The cerebrovascular microcirculatory resistance was applied to estimate post-operative blood velocity and flow rates. Pearson correlation and Bland-Altman analyses were used to evaluate the correlation and agreement between CFD calculations and transcranial Doppler (TCD) measurements.

RESULTS

There was a strong correlation between CFD- and TCD-based mean velocities (r = 0.7733; P = 0.0002), with volume flow measured by both methods also showing robust correlation (r = 0.8621; P < 0.0001). Additionally, agreement was found between mean velocities determined by CFD simulation and those estimated by TCD (P = 0.2446, mean difference -4.2089; limits of agreement -11.5764 to 3.1586). However, agreement between volume flow from CFD simulations and TCD was less consistent (P = 0.0387, mean difference -0.3272, limits of agreement -0.9276 to 0.2731).

CONCLUSIONS

The computational method used in this study enables the prediction of hemodynamic changes and offers valuable support in tailoring treatment strategies for cerebrovascular stenosis lesions.

Optimizing Treatment of Significant Carotid Artery Stenosis in Times of Logistic Restraints as a Result of COVID-19 Pandemic

BACKGROUND

COVID-19 confronted medical care with many challenges. During the pandemic, several resources were limited resulting in renouncing or postponing medical care like carotid endarterectomy (CEA) for patients with significant carotid artery stenosis. Although according to international guidelines CEA is the first choice, carotid artery stenting (CAS) could potentially be a reasonable alternative especially during logistical restraints.

PURPOSE

To evaluate outcomes of CAS versus CEA before, during and after the COVID-19 pandemic. Our hypothesis was that a CAS first approach yielded comparable outcomes compared to a CEA first approach.

METHODS

Retrospective analysis of consecutive patients with significant carotid artery stenosis treated with CEA or CAS between September 2018 and March 2023. Each consecutive period of 1.5 year marked a new (treatment) period: pre-COVID (CEA first strategy), during COVID (CAS first strategy) and post-COVID (patient-tailored approach). Primary outcome was the composite endpoint of stroke, transient ischemic attack or death within 30 days. Secondary outcome consisted of the rate of technical success, cerebral hyperperfusion syndrome, myocardial infarction or other cardiac complications needing intervention, bleeding of the surgical site needing intervention, nerve palsy, unintended IC admission, pseudoaneurysm, restenosis, or occlusion.

RESULTS

A total of 318 patients were included. Out of 137 patients treated with CEA, 55, 36 and 46 were treated pre-COVID, during COVID and post-COVID, respectively. Out of 181 CAS procedures, 38, 59 and 84, respectively, were performed in each time period. Primary outcome occurred in 5.5%, 0% and 2.2% in the CEA group and 0%, 1.7% and 3.6% in the CAS group (P = 0.27; P = 1.00; P = 1.00, respectively). Overall technical success was 100% for CEA and 99.4% for CAS (P = 1.00). Rate of restenosis was the only secondary outcome measure which was significantly better after CAS compared to CEA in the pre- and post-COVID period (CEA vs. CAS, 12.7% vs. 7.9%, and 23.9% vs. 4.8% with a P-value of 0.03 and 0.03, respectively). Hospital presentation to treatment interval did not differ significantly during the pandemic.

CONCLUSIONS

Outcomes were comparable between CAS versus CEA in patients with significant carotid artery stenosis before, during and after the COVID-19 pandemic. CAS showed better results in terms of other complications (i.e., restenosis rate) in the pre- and post-COVID period compared to CEA. Our results may support a CAS first approach when no relevant contra-indications exist without exposing the patient to complications associated with an open surgical approach. Discussion in a multidisciplinary team is advised.

Combination of intraoperative indocyanine green video-angiography FLOW 800 and computed tomography perfusion to assess the risk of cerebral hyperperfusion syndrome in chronic internal carotid artery occlusion patients after revascularization surgery

Background and purpose

To study the changes of corticocerebral hemodynamics in surgical area and postoperative hyperperfusion syndrome in patients with chronic internal carotid artery occlusion (CICAO) by intraoperative indocyanine green videoangiography (ICGA)-FLOW 800 and CT perfusion after superficial temporal artery (STA)-middle cerebral artery (MCA) bypass surgery.

Methods

From October 2019 to January 2021, 77 patients diagnosed with CICAO underwent direct bypass surgery at Huadong hospital (affiliated with Fudan University) were enrolled. Regions of interest (ROIs) at STA, proximal MCA (PMCA), distal MCA (DMCA), cortical blood capillary (CBC), and cortical vein (CV) were identified after anastomosis by ICGV-FLOW 800 including peak fluorescence intensity (PFI), time to peak (TTP), and area under the time curve (AUC) of fluorescence intensity. All patients underwent perfusion-weighted CT before bypass surgery and those patients with HPS were verified by CTP after bypass.

Results

14 patients with HPS were verified by perfusion-weighted CT after bypass. In HPS group, the AUCTTP of DMCA was significantly larger (T = -3.301, p = 0.004) and TTP of CBC was shorter (T = -2.929, p = 0.005) than patients in non-HPS group. The larger AUCTTP of DMCA (OR = 3.024, 95%CI 1.390-6.578, p = 0.0050) was an independent risk factor by further multivariate logistic regression analysis.

Conclusion

The hemodynamic changes of cortical vessels during STA-MCA bypass surgery could be recorded accurately by ICGV-FLOW 800. Furthermore, the increased AUCTTP of DMCA and shorter TTP of CBC may be potential risk factors of HPS.

Cerebral Hyperperfusion Syndrome Presenting as Epilepsia partialis Continua Following Carotid Stenting: A Case Report

Cerebral hyperperfusion syndrome (CHS) is a rare prodrome of symptoms, including headaches, focal neurological deficits, seizures, or encephalopathy. Herein, we report a unique case of focal motor status epilepticus (Epilepsia partialis continua [EPC]). A 76-year-old male underwent right carotid stenting (CAS) for symptomatic high-grade stenosis. Immediately post-operation, he was recovering well without neurologic deficits; however, four days later, his blood pressure increased, and he experienced focal motor seizures involving the left arm and face without impaired awareness. He was managed with antihypertensive and antiseizure medications. Subsequently, his respiratory function worsened, necessitating intubation for status epilepticus. Repeated imaging demonstrated only the previously known infarcts without cerebral edema, bilaterally patent carotid arteries or any signs of acute infarct or intracerebral hemorrhage.  While CHS is a rare syndrome with well-documented symptomatology, focal motor status epilepticus can occur abruptly without the more typical CHS symptoms, despite the best preventive measures.

Hemodynamic instability in the immediate postoperative setting after transcarotid artery revascularization

OBJECTIVE

Transcarotid artery revascularization (TCAR) is a relatively recent development in the management of carotid artery occlusive disease, the utilization of which is becoming more prevalent. This study aims to evaluate the timing, prevalence, and types of hemodynamic instability after TCAR.

METHODS

We performed a retrospective review of all TCAR procedures performed at two tertiary care academic medical centers within a single hospital system from 2017 through 2019. Demographics, comorbidities, preoperative patient factors, procedural details, and postoperative data were collected. Patients were assessed over 24 hours postoperatively for stroke, death, myocardial infarction (MI), and hemodynamic instability at 3, 6, 9, 12, and 24 hour intervals. Hemodynamic instability was defined as any vital sign abnormality which required pharmacological intervention with antihypertensive, vasopressor, and/or anti-arrhythmic agents. The incidence and timing of postoperative complications and hemodynamic instability were recorded.

RESULTS

During the study period, 76 patients 80 TCAR procedures. Out of 80 procedures, 64 (80.0%) were receiving home antihypertensive medication and 28 (35.0%) were symptomatic lesions preoperatively. Intraoperatively, one patient (1.3%) received atropine, 26 (32.5%) received glycopyrrolate, 76 (95%) underwent predilatation, and 16 (20.0%) underwent postdilatation. Postoperatively, a total of 22 cases (27.5%) required medication for acute control of blood pressure or heart rate, which reached a peak of 19 patients (23.8%) within the first 3 hours, and tapered to nine patients (11.3%) by the 24 hour mark. A total of three patients (3.75%) required initiation of pharmacological management after the three-hour mark. Six patients (7.5%) underwent stroke code workup, 4 (5.0%) of whom were confirmed to have stroke on CT. Average time to neurologic event was 3.9 hours. No patients experienced MI or death. Median ICU and hospital days for unstable patients were two and three, respectively, compared to one and one for stable patients.

CONCLUSIONS

Hemodynamic instability is common after TCAR and reliably presents at or before postoperative hour 3. Hypo- followed by hyper-tension were the most common manifestations of hemodynamic instability. Regardless, unstable patients and stroke patients were more likely to require longer periods of time in the ICU and in the hospital overall. This may have implications for postoperative ICU resource management when deciding to transfer patients out of a monitored setting. Further study is required to establish relationships between pre- and intra-operative risk factors and outcomes such as hemodynamic instability and/or stroke. At present, one should proceed with careful evaluation of preoperative medications, strict management of postoperative hemodynamics, and clear communication among team members should all be employed to optimize outcomes.

Todd's paralysis due to hyperperfusion syndrome after carotid endarterectomy mimicking postoperative stroke

Todd's paralysis is a neurological deficit that is observed in <10% of patients following epileptic seizures. Cerebral hyperperfusion syndrome (CHS) is a rare complication following carotid endarterectomy (CEA), seen in 0-3% of the patients, characterized by focal neurological deficit, headache, disorientation, and sometimes seizures. In this case report, we present a case of CHS after CEA followed by seizures and Todd's paralysis that mimicked postoperative stroke. A 75-year-old female patient was admitted for CEA of the right internal carotid artery, following a transient ischemic attack two months prior. Four hours after CEA with graft interposition, the patient suffered a temporary weakness of the left arm and leg followed by generalized spasms within a few seconds. CT angiography showed regular patency of the carotid arteries and the graft, and brain CT showed no sign of oedema, ischemia or hemorrhage. However, left-sided hemiplegia occurred following the seizure, and the patient suffered four more seizures over the next 48 hours, with persisting hemiplegia. On the second postoperative day, the motor skills of the left side fully recovered, and the patient was communicative, and of orderly mental status. Brain CT performed on the third postoperative day showed entire right hemisphere oedema. A moderate hemiparesis with seizures as a consequence of CHS after CEA has been described, however in all cases with seizures and hemiplegia, the underlying cause was always a verified stroke or intracerebral hemorrhage. This case highlights the importance of considering Todd's paralysis in patients with seizures after CEA due to CHS and prolonged periods of hemiplegia after the seizures.

Non responsible vascular area hyperperfusion syndrome after mechanical thrombectomy for vertebral artery occlusion: A case report

Introduction

There are currently no published reports of hyperperfusion syndrome in the non responsible vascular area after mechanical thrombectomy for acute cerebral infarction with large vessel occlusion. Here, we report a case of hyperperfusion syndrome in the blood supply area of the right middle cerebral artery after mechanical thrombectomy for acute cerebral infarction after vertebral artery occlusion.

Patient concerns

A 21-year-old woman developed left vertebral artery occlusion, for which she received mechanical thrombectomy and successful recanalization of her occluded cerebral vessel. Subsequently, the patient became extremely agitated, with high blood pressure and headache.

Diagnosis

Two hours after the operation, bedside transcranial Doppler ultrasound examination found that the cerebral blood flow velocity of the M1 segment of the right middle cerebral artery was more than twice that of the left middle cerebral artery. Combined with the symptoms, signs and examination results of the patient, hyperperfusion syndrome in the blood supply area of the right middle cerebral artery was considered.

Interventions

The patient was administered sedation, and her pressure and ventricular rate were strictly controlled. She was no longer agitated, and her headache was significantly relieved at 36 hours after the operation.

Outcomes

On the 5th day after the operation, the blood flow velocity of her right middle cerebral artery decreased to normal level, and the patient recovered well.

Conclusion

In this case, after mechanical thrombectomy, such patients with acute posterior circulation cerebral infarction can experience hyperperfusion syndrome in the non responsible vascular area of the anterior circulation. Bedside transcranial Doppler cerebral blood flow examination can identify the hyperperfusion state of cerebral vessels in a timely manner and effectively guide treatment.

Cerebral Perfusion and Neuromonitoring during Complex Aortic Arch Surgery: A Narrative Review

Complex ascending and aortic arch surgery requires the implementation of different cerebral protection strategies to avoid or limit the probability of intraoperative brain damage during circulatory arrest. The etiology of the damage is multifactorial, involving cerebral embolism, hypoperfusion, hypoxia and inflammatory response. These protective strategies include the use of deep or moderate hypothermia to reduce the cerebral oxygen consumption, allowing the toleration of a variable period of absence of cerebral blood flow, and the use of different cerebral perfusion techniques, both anterograde and retrograde, on top of hypothermia, to avoid any period of intraoperative brain ischemia. In this narrative review, the pathophysiology of cerebral damage during aortic surgery is described. The different options for brain protection, including hypothermia, anterograde or retrograde cerebral perfusion, are also analyzed, with a critical review of the advantages and limitations under a technical point of view. Finally, the current systems of intraoperative brain monitoring are also discussed.

Effect of perioperative blood pressure variability on cerebral hyperperfusion syndrome after carotid artery stenting: A retrospective study

OBJECTIVE

To investigate the effect of perioperative blood pressure variability on cerebral hyperperfusion syndrome after carotid artery stenting.

METHODS

A retrospective analysis was conducted of data collected from 418 patients who underwent carotid artery stenting in Guangxi Zhuang Autonomous Region People's Hospital in China. The blood pressure data were collected during operation (after balloon dilation, before stent release, after stent release) and within 3 days after the operation. The blood pressure variability was evaluated by measuring the mean, maximum, minimum, max-min, standard deviation (SD) of systolic blood pressure (SBP) and diastolic blood pressure (DBP). The correlation between blood pressure variability and cerebral hyperperfusion syndrome was analysed.

RESULTS

Blood pressure data from 418 patients were analysed. Twenty patients (4.8%) developed cerebral hyperperfusion syndrome. The parameters of blood pressure variability were divided into four groups according to quartile. After adjusting for age, symptomatic carotid stenosis, unilateral carotid stenosis, bilateral carotid stenosis, collateral circulation, diabetes mellitus and chronic kidney disease, multivariate analysis showed that SBPMax, SBPMin, SBPMax-Min, SBPCV, DBPSD, DBPMax, DBPMin, DBPMax-Min and DBPCV were associated with the occurrence of cerebral hyperperfusion syndrome (P < 0.05), respectively.

CONCLUSION

This study suggests that blood pressure variability during the perioperative period may increase the risk of cerebral hyperperfusion syndrome.

Preoperative evaluation and perioperative management of patients undergoing major vascular surgery

Patients undergoing major vascular surgery have an increased risk of perioperative major adverse cardiovascular events (MACE). Accordingly, in this population, it is of particular importance to appropriately risk stratify patients' risk for these complications and optimize risk factors prior to surgical intervention. Comorbidities that portend a higher risk of perioperative MACE include coronary artery disease, heart failure, left-sided valvular heart disease, and significant arrhythmic burden. In this review, we provide a current approach to risk stratification prior to major vascular surgery and describe the strengths and weaknesses of different cardiac risk indices; discuss the role of noninvasive and invasive cardiac testing; and review perioperative pharmacotherapies.

Intraoperative Transcranial Doppler Monitoring Predicts the Risk of Cerebral Hyperperfusion Syndrome After Carotid Endarterectomy

OBJECTIVE

Cerebral hyperperfusion syndrome (CHS) is a rare but serious complication following carotid endarterectomy (CEA). The aim of this study was to identify intraoperative transcranial Doppler (TCD) hemodynamic predictors of CHS after CEA.

METHODS

Between January 2013 and December 2018, intraoperative TCD monitoring was performed for 969 patients who underwent CEA. The percentage increase in the mean velocity of the middle cerebral artery (MCAV%) at 3 postdeclamping time points (immediately after declamping, 5 minutes after declamping, and after suturing the skin) over baseline was compared between CHS and non-CHS patients.

RESULTS

CHS was diagnosed in 31 patients (3.2%), including 11 with intracranial hemorrhage. The MCAV% values at the 3 postdeclamping time points over baseline were 177% (81%-275%), 90% (41%-175%), and 107% (55%-191%) in the CHS group, significantly higher than those in the non-CHS group (40% [14%-75%], 15% [1%-36%], and 18% [3%-41%], respectively, all P < 0.001). Receiver operating characteristic curve analysis showed that the 3 intraoperative MCAV% parameters all had excellent accuracy in identifying CHS (areas under the curve: 0.854, 0.839, and 0.858, respectively, all P < 0.001). The predictive value of the model consisting only of preoperative parameters was significantly increased by adding the intraoperative TCD hemodynamic parameters (area under the curve: 0.747 vs. 0.858, P = 0.006). Multivariate analyses identified the intraoperative MCAV% immediately after declamping (odds ratio: 9.840, 95% confidence interval: 2.638-36.696, P < 0.001) as an independent predictor of CHS.

CONCLUSIONS

Our results indicate that intraoperative TCD monitoring helps predict CHS after CEA at an early stage.

Anesthetic management of carotid endarterectomy: an update from Italian guidelines

BACKGROUND AND AIMS

In order to systematically review the latest evidence on anesthesia, intraoperative neurologic monitoring, postoperative heparin reversal, and postoperative blood pressure management for carotid endarterectomy. The present review is based on a single chapter of the Italian Health Institute Guidelines for diagnosis and treatment of extracranial carotid stenosis and stroke prevention.

METHODS AND RESULTS

A systematic article review focused on the previously cited topics published between January 2016 and October 2020 has been performed; we looked for both primary and secondary studies in the extensive archive of Medline/PubMed and Cochrane library databases. We selected 14 systematic reviews and meta-analyses, 13 randomized controlled trials, 8 observational studies, and 1 narrative review. Based on this analysis, syntheses of the available evidence were shared and recommendations were indicated complying with the GRADE-SIGN version methodology.

CONCLUSIONS

From this up-to-date analysis, it has emerged that any type of anesthesia and neurological monitoring method is related to a better outcome after carotid endarterectomy. In addition, insufficient evidence was found to justify reversal or no-reversal of heparin at the end of surgery. Furthermore, despite a low evidence level, a suggestion for blood pressure monitoring in the postoperative period was formulated.

Relationship between cerebral hyperperfusion syndrome and the immediate change of cerebral blood flow after carotid artery stenting evaluated by single-photon emission computed tomography

PURPOSE

Cerebral hyperperfusion syndrome (CHS) is a critical complication after carotid artery stenting (CAS). However, few CAS studies have evaluated immediate and temporary changes in ipsilateral cerebral blood flow (CBF) quantitatively. The study was performed to evaluate immediate changes in CBF after CAS and subsequent CBF changes in patients with cerebral hyperperfusion (HP) using ¹²³I-IMP SPECT.

METHODS

The subjects were 223 patients with chronic extracranial carotid artery stenosis who underwent CAS in our department between March 2010 and March 2020. Quantitative CBF and cerebrovascular reactivity to acetazolamide in the middle cerebral artery were assessed before CAS by ¹²³I-IMP SPECT. CBF was also measured immediately after CAS by ¹²³I-IMP SPECT. When HP was detected, CBF was measured again 3 and 7 days after CAS.

RESULTS

The median (interquartile range) ipsilateral quantitative CBF change after CAS was - 0.1% (- 9.5-8.2%), and the upper value of the 95% CI of the quantitative CBF change was 48.2%. Thus, we defined HP after CAS as an increase in quantitative CBF of > 48.2% compared with the preoperative value. Of 223 patients, 5 (2.2%) had HP, and 4 of these patients (80%) developed CHS. In the CHS patients, HP was maintained for about 3 days and improved after about 7 days.

CONCLUSION

An immediate CBF increase of > 48.2% after CAS may lead to development of CHS. In CHS after CAS, HP persisted for about 1 week and postoperative management may be required for at least 1 week.

Peri-Procedural Management of Hemodynamic Instability in Patients Undergoing Carotid Revascularization

Acute perioperative changes in arterial pressure occur frequently, particularly in patients with cardiovascular disease or those receiving vasoactive medications, or in relation to certain cardiovascular surgical procedures. Hemodynamic Instability (HI) are common in patients undergoing carotid revascularization because of unique patho-physiological and surgical factors. The operation, by necessity, disrupts the afferent pathway of the baroreflex, which can lead to postendarterectomy HI. Poor arterial pressure control is associated with increased morbidity and mortality after carotid revascularization, but good control of arterial pressure is often difficult to achieve in practice. The incidence, implications, and etiology of HI associated with carotid surgery are reviewed, and some recommendations made for its management. Close monitoring and titration of therapy are probably the most important considerations rather than specific choice of agents.

Cerebral Hyperperfusion Syndrome Presenting As Status Epilepticus Following Carotid Endarterectomy

Cerebral Hyperperfusion Syndrome (CHS) is a rare syndrome, commonly described as a prodrome of symptoms including a severe ipsilateral headache, focal neurological deficits, intracerebral hemorrhage, and occasionally includes seizures or encephalopathy. Our case involves a 76-year-old man who underwent a left carotid endarterectomy (CEA) for symptomatic high-grade stenosis of his left carotid artery. Post-operative day one, the patient was seen and examined in the early morning and found to be doing well, with blood pressures well-controlled and at his neurologic baseline. Three hours later, he was reported to have a sudden spike in his blood pressure and was experiencing focal motor seizures involving the right arm and face, both of which were unrelieved by anti-hypertensives and anti-seizure medications. The patient subsequently developed worsening respiratory function requiring intubation for status epilepticus. Repeat head and neck imaging with CT, CT angiography, and MRI demonstrated the known previous subacute infarct with new cerebral edema, patent carotid arteries bilaterally, and no acute infarct or intracerebral hemorrhage. While CHS is a rare syndrome with well-documented symptomatology, we present a unique case in which focal motor status epilepticus was the only presenting symptom in a patient who otherwise meets the criteria of CHS based on radiographic evidence of cerebral edema following an elective CEA.

The periprocedural and 30-day outcomes of carotid stenting in patients with carotid artery near-occlusion

The safety of endovascular revascularization in patients with carotid artery near occlusion (CANO) is unknown. We aimed to evaluate the peri-procedural risk in CANO patients receiving carotid artery stenting (CAS). A prospective data base with retrospective review was performed to identify patients who underwent CAS with CANO from July 2006 to July 2020, and had at least 1-month clinical follow-up data. The primary endpoints were stroke, hyperperfusion syndrome, and death within 30 days after CAS. A total of 198 patients with carotid artery stenosis were enrolled including 92 patients with CANO and 106 age and sex-matched patients with 70–99% conventional carotid stenosis. Full distal carotid collapse was found in 45 CANO patients (45/92, 49%). The technical success rate was 100%. The CANO patients had significantly longer lesion lengths compared with those of the non-CANO group. The incidence of hyperperfusion syndrome was comparable (CANO: 2.2%, non-CANO: 0.9%, P = 0.598). The risks of ischemic stroke and death within 30 days were 1.1% and 0% in the CANO group; and 1.9% and 0.9%, in the non-CANO group, respectively, without statistical difference. In conclusion, CAS is safe for patients with CANO, with a similar low 30-day peri-procedural event rate comparable to those of non-CANO.

Influence of Eversion Endarterectomy and Patch Reconstruction on Postoperative Blood Pressure After Carotid Surgery

BACKGROUND

Post carotid blood pressure fluctuation and hypertension (PEH) are associated with increased risk for adverse outcome; there is limited evidence on the impact of eversion endarterectomy (E-CEA) versus conventional endarterectomy with patch closure (C-CEA) on postoperative blood pressure course.

PATIENTS AND METHODS

In this retrospective observational study, 859 consecutive carotid endarterectomy procedures between 2004 and 2014 (C-CEA n = 585 vs. E-CEA n = 274), were evaluated. Pre- and postoperative blood pressure values were recorded from recovery room until third postoperative day and compared between both techniques; influences on the dichotomous target variable "at least one postoperative blood pressure peak", that is need for postoperative vasodilators, were analyzed by a logistic regression model. Influences on postoperative systolic blood pressure were evaluated by a linear mixed effects regression model.

RESULTS

Preoperative baseline blood pressure was not different between both comparison groups. During postoperative course, significantly increased mean systolic blood pressure values in the E-CEA group from recovery room to second postoperative day (recovery room C-CEA: 129.2 mm Hg vs. E-CEA: 136.5 mm Hg; P < 0.001; first postoperative day C-CEA: 132.4 mm Hg vs. E-CEA: 139.3 mm Hg; P = 0.0002; second postoperative day C-CEA: 138.6 mm Hg vs. E-CEA: 143.1 mm Hg; P = 0.023) were observed. No hyperperfusion syndrome was detected as wells as no difference in postoperative complication rate. Frequency of antihypertensive interventions was also elevated in E-CEA group (C-CEA 22.1 % vs. E-CEA 31.8 %; P = 0.003). E-CEA (OR 1.591, 95% CI [1.146; 2.202]; P = 0.005) and presence of preoperatively elevated systolic readings (OR 1.015, 95%CI [1.006;1.024]; P < 0.001) was also associated with increased need for antihypertensive interventions.

CONCLUSION

E-CEA was associated with significantly elevated postoperative blood pressure, compared to C-CEA. C-CEA was associated with postoperative blood pressure decrease; however, no difference as to neurologic and surgical complications was detected between both surgical techniques in clinical practice.

Prevalence and Clinical Predictors of Intracranial Hemorrhage Following Carotid Artery Stenting for Symptomatic Severe Carotid Stenosis

OBJECTIVE

Hyperperfusion-induced intracranial hemorrhage (HICH) is the most frequent cause of death following carotid artery stenting (CAS). This study aimed to identify the presence of HICH after CAS and evaluate demographic and clinical variables associated with HICH.

METHODS

We retrospectively reviewed clinical data of 446 consecutive patients with symptomatic severe carotid stenosis treated with CAS between November 2011 and August 2018. Good collateral compensation was defined as patency of the anterior communicating artery with well-developed bilateral A1 segments with or without posterior communicating arteries, according to the classification of Katano et al. Univariate and multivariate analyses were performed to determine whether there was a correlation between demographic and clinical variables and development of HICH.

RESULTS

Stent placement was successful in all patients. Of 446 patients, 14 had HICH (3.14%); 1 of 14 (7.14%) patients displayed 80%-90% stenosis, and 13 patients had stenosis ≥90%. Thirteen patients (92.86%) had poor collateral circulation compensation. Two patients (14.3%) died despite rescue efforts. Age (≥70 years), degree of carotid artery stenosis (≥90%), and poor compensation of collateral circulation were associated with a higher frequency of HICH after CAS. Severe carotid artery stenosis (≥90%) was independently associated with HICH after stenting (odds ratio 13.633, P = 0.014).

CONCLUSIONS

The incidence rate of HICH was 3.14%. Patients with severe carotid artery stenosis (≥90%) are at high risk for developing HICH after CAS. Further investigations are needed to better describe the contribution of other risk factors, including poor compensation of collateral circulation (especially anterior circulation).

Recanalization of symptomatic chronic internal carotid artery occlusions by hybrid treatment

OBJECTIVE

To evaluate the efficacy and safety of hybrid revascularization by carotid endarterectomy and endovascular intervention in the treatment of chronic internal carotid artery occlusion (ICAO).

METHODS

We performed a retrospective analysis of patients who received hybrid treatment for symptomatic chronic ICAO between December 2016 and December 2018. Fifty-six patients with long-segment ICAO were enrolled and divided into the short duration (1-3 months) and long ICAO duration (>3 months) groups, and their clinical and angiographic data were analyzed.

RESULTS

The mean duration was 106.8 ± 36.1 days from the date of ICAO diagnosis to revascularization. Totally, 10 patients (17.8%, n = 56) in the short duration group while no patients in the long duration group failed recanalization (n = 7). Perioperative complications included intraoperative thromboembolism in 1 (1.8%) patient and subarachnoid hemorrhage in 2 (3.6%) patients. Early phase postoperative hypertension was noted in 11 (19.6%) patients and cervical hemorrhage in 1 (1.8%) patient. No severe neurological deficits occurred. Overall, the 6-month modified Rankin score, Mini-mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA) scores in patients with successful recanalization significantly improved versus the baseline (P < 0.05). After successful recanalization, the long duration group demonstrated more stents for revascularization compared with the short duration group (P < 0.05). Five (10.8%) patients had recurrent transient ischemic attack, and 1 (2.2%) patient developed stroke in the successful revascularization group during 6 months of follow-up. ICA restenosis occurred in 5 (8.9%) patients and re-occlusion was noted in 1 (1.8%) patient.

CONCLUSIONS

Hybrid operation may be feasible and effective for patients with symptomatic chronic complete ICAO according to our limited data. The original occlusion site from the carotid bifurcation and the duration of ICAO should be considered as independent indicators for successful recanalization as well as perioperative outcomes.

Age corrected changes in intracranial hemodynamics after carotid endarterectomy

BACKGROUND

Transcranial Doppler ultrasound (TCD) is a frequently used method to monitor brain perfusion during and following carotid endarterectomy (CEA). Our aim was to define the normally occurring changes of intracranial hemodynamics in patients undergoing CEA measuring recently developed TCD parameters.

METHODS

A retrospective, single-center cohort study was performed. Patients undergoing CEA were evaluated pre- and postoperatively from day 0 to day 3 measuring middle cerebral artery flow velocity (MCAFV). The following parameters were analyzed: the first systolic peak (Sys1), the second systolic peak (Sys2) and diastolic flow velocity at a fixed time after heartbeat onset (Dias@560). These parameters linearly decrease with age and were, therefore, transformed to Z-scores.

RESULTS

Three hundred eighteen patients were included with a mean age of 70.8 years. Most patients were male (71%). Compared to preoperatively, the Z-scores of Sys1 and Sys2 were larger on postoperative day 3: +1.12 standard deviation (SD) or 16.0 cm/s (CI: 0.93 to 1.32; P<0.001) and +0.55 SD or 7.8 cm/s (CI: 0.35 to 0.74; P<0.001), respectively. The Z-score for Dias@560 was smaller than preoperatively: -0.23 SD or -1.9 cm/s (CI: -0.41 to -0.05, P=0.015).

CONCLUSIONS

Under normal circumstances Sys1 profits more from CEA than Sys2, whilst diastolic flow velocity decreases. This indicates a return to normal arteriolar vascular resistance. Carefully describing normal changes in MCAFV, may in future enable discrimination of abnormalities, such as hyperperfusion syndrome.

Blood–Brain Barrier Disturbances and Potential Complications of Endovascular Management in Stroke—Technical Note with Limited Review

Contrast enhancement (CE), contrast extravasation (CX), hemorrhagic transformation (HT), and cerebral hyperperfusion syndrome (CHS) in patients who have suffered ischemic stroke and have undergone revascularization. There are a handful of articles addressing these pathologies separately. But there is scant literature available combining them together, as the underlying pathophysiology involves disturbances of blood–brain barrier (BBB). We have reviewed literature and proposed a common mechanism for these events. We systematically searched PubMed, LibGen, Cochrane, and Sci-Hub databases for the studies published online regarding CE, CX, HT, and CHS after endovascular treatment for stroke. This review was conducted based on the PRISMA guidelines. The following medical search terms were used for the online search: contrast enhancement, contrast extravasation, hemorrhagic transformation, cerebral hyperperfusion syndrome, endovascular treatment, contrast staining, postprocedural attenuation, carotid stenting, intra-arterial thrombolysis, and stroke. We did a limited review of literature by analyzing the relevant articles and research papers published to date. We have randomly included prototype cases of CE, CX, HT, and CHS which we have encountered in our Interventional Department from our own database. In compliance with PRISMA guidelines, we screened 33 articles dealing with CE, 32 with CX, 26 articles that addressed CE and CX both, 53 articles dealing with HT, and 42 articles dealing with CHS. Overall, 88 articles were filtered on studying the abstract. Further, 15 more had to be excluded as reasoned in the flowchart, and finally 71 articles were included in our study, as again shown in the flowchart. We studied and discussed these articles and research papers in relation to pathophysiology, predisposing factors, preventive measures, and current treatment protocols. BBB disruption is the primary event in CE, CX, HT, and CHS with varying severity. Minimizing dose of contrast, optimum timing of revascularization and dose of thrombolytic, judicious selection of mechanical thrombectomy cases, and strict control of blood pressure in postrevascularization period are recommended preventive measures. High-index of clinical suspicion, early imaging to detect, and following-up the same on sequential imaging are key to avoid severe forms of HT and CHS.

Defining a Taxonomy of Intracranial Hypertension: Is ICP More Than Just a Number?

Intracranial pressure (ICP) monitoring and control is a cornerstone of neuroanesthesia and neurocritical care. However, because elevated ICP can be due to multiple pathophysiological processes, its interpretation is not straightforward. We propose a formal taxonomy of intracranial hypertension, which defines ICP elevations into 3 major pathophysiological subsets: increased cerebral blood volume, masses and edema, and hydrocephalus. (1) Increased cerebral blood volume increases ICP and arises secondary to arterial or venous hypervolemia. Arterial hypervolemia is produced by autoregulated or dysregulated vasodilation, both of which are importantly and disparately affected by systemic blood pressure. Dysregulated vasodilation tends to be worsened by arterial hypertension. In contrast, autoregulated vasodilation contributes to intracranial hypertension during decreases in cerebral perfusion pressure that occur within the normal range of cerebral autoregulation. Venous hypervolemia is produced by Starling resistor outflow obstruction, venous occlusion, and very high extracranial venous pressure. Starling resistor outflow obstruction tends to arise when cerebrospinal fluid pressure causes venous compression to thus increase tissue pressure and worsen tissue edema (and ICP elevation), producing a positive feedback ICP cycle. (2) Masses and edema are conditions that increase brain tissue volume and ICP, causing both vascular compression and decrease in cerebral perfusion pressure leading to oligemia. Brain edema is either vasogenic or cytotoxic, each with disparate causes and often linked to cerebral blood flow or blood volume abnormalities. Masses may arise from hematoma or neoplasia. (3) Hydrocephalus can also increase ICP, and is either communicating or noncommunicating. Further research is warranted to ascertain whether ICP therapy should be tailored to these physiological subsets of intracranial hypertension.

Cerebrovacular Reserve Predicts the Cerebral Hyperperfusion Syndrome After Carotid Endarterectomy

BACKGROUND

Cerebral hyperperfusion syndrome is a rare but potentially severe complication of carotid artery revascularisation that develops under conditions of resistant postoperative hypertension and impaired cerebrovascular autoregulation.

OBJECTIVE

Was to determine which preoperative and operative factors affect the development of cerebral hyperperfusion syndrome after carotid endarterectomy.

METHODS

This prospective observational study enrolled 93 asymptomatic patients who underwent carotid endarterectomy. Cerebral hyperperfusion was registered in patients who had 100% postoperative increase in mean flow in middle cerebral artery registered by Transcranial Doppler ultrasound. Cerebral hyperperfusion syndrome was diagnosed in patients with cerebral hyperperfusion who postoperatively developed at least one of the symptoms. Pre-operative and operative risk factors for cerebral hyperperfusion syndrome were analysed by multivariate binary logistic regression.

RESULTS

Out of 93 operated patients, cerebral hyperperfusion was registered in 23 and cerebral hyperperfusion syndrome in 18 patients. Risk factors for cerebral hyperperfusion syndrome were included in the binary logistic regression model. Incomplete Circle of Willis morphology on 3D TOF magnetic resonance image (p = 0.002), Breath holding index below the 0.69 cut-off (p = 0.006), positive criteria for insufficient collateral flow through circle of Willis registered by TCD (p = 0.03), and poorly controlled hypertension (p = 0.023) showed statistically significant independent predictive value for cerebral hyperperfusion syndrome. The model was statistically significant (p = 0.012) and correctly classified 90.3 % of patients.

CONCLUSIONS

Incomplete circle of Willis and insufficient collateral flow, low cerebrovascular reserve, and poorly regulated hypertension are significant predictors of post- carotid endarterectomy hyperperfusion development.

Perioperative baseline -blockers: An independent protective factor for post-carotid endarterectomy hypertension

OBJECTIVE

Post-carotid endarterectomy hypertension is a well-recognized phenomenon closely related to surgical complications. This study aimed to determine whether different kinds of perioperative antihypertensive drugs had a protective effect on post-carotid endarterectomy hypertension and influence on intraoperative hemodynamics.

METHOD

We retrospectively investigated 102 carotid stenosis patients who underwent conventional endarterectomy with a perioperative baseline antihypertensive regimen. Post-carotid endarterectomy hypertension was defined as a postoperative peak systolic blood pressure ≥160 mmHg and/or a requirement for any additional antihypertensive therapies. We compared the clinical characteristics and types of baseline perioperative antihypertensive drugs between patients with and without post-carotid endarterectomy hypertension and then determined the significant independent effect of antihypertensive drugs on post-carotid endarterectomy hypertension through multivariate regression and detected their influence on intraoperative hypertension (induction-related systolic blood pressure and vasodilators consumption) and hemodynamic depression (intra-arterial systolic blood pressure ≤100 mmHg and/or heart rate ≤50 beats/min). We also investigated adverse events such as stroke, death, myocardial infarction, and cerebral hyperperfusion syndrome during the postoperative hospitalization.

RESULTS

A total of 52/102 (51.0%) patients were defined as having post-carotid endarterectomy hypertension during the first three days postoperative, including eight patients with a postoperative systolic blood pressure that exceeded 160 mmHg at least once, 31 patients requiring postoperative antihypertensive treatment in addition to their baseline regimen, and 13 patients with both. The incidence of stroke/death/myocardial infarction and cerebral hyperperfusion syndrome after conventional endarterectomy during hospitalization were both 1.9%. A significantly increased risk of composite postoperative complications (including cerebral hyperperfusion syndrome, hyperperfusion-related symptoms, transient ischemic attacks, stroke, death, and cardiac complications) was observed in patients with post-carotid endarterectomy hypertension than without (15.4% versus 2.0%, p = 0.032). Patients free of post-carotid endarterectomy hypertension had a higher incidence of perioperative baseline β-blocker use than patients who suffered from post-carotid endarterectomy hypertension (46.0% versus 21%, p = 0.008). In multivariate analysis, β-blocker use was a significant independent protective factor for post-carotid endarterectomy hypertension (OR = 0.356, 95% CI: 0.146-0.886, p = 0.028). Patients taking β-blockers had a lower postoperative peak systolic blood pressure than the β-blocker-naïve population (137.1 ± 12.1 mmHg versus 145.0 ± 11.2 mmHg, p = 0.008), but the postoperative mean systolic blood pressure showed no intergroup difference. However, the incidence of hemodynamic depression during conventional endarterectomy was higher in patients with perioperative β-blocker use than in those without (44.1% versus 25.0%, p = 0.050). The difference in intraoperative hemodynamic depression became more prominent between the β-blocker and non-β-blocker groups (81.8% versus 33.3%, p = 0.014) for whose preoperative baseline heart rate was equal to or lower than 70 beats/min.

CONCLUSION

The perioperative use of β-blockers is a protective factor for post-carotid endarterectomy hypertension and contributes to stabilizing the postoperative peak systolic blood pressure three days after conventional endarterectomy. However, β-blockers might also lead to intraoperative hemodynamic depression, especially for patients with a low baseline heart rate.

Hemodynamic changes between different anatomically designed stents after carotid stenting: a prospective multicenter study

BACKGROUND

The aim of this study was to investigate differences in the dynamic changes and risk factors of hemodynamic depression (HD) between straight and tapered carotid stenting (SCS and TCS, respectively).

METHODS

A total of 148 and 167 patients were included in TCS and SCS groups in this study, respectively. All clinical data were collected and analyzed for differences in HD and primary endpoint events at 12 months.

RESULTS

The SCS procedure had a lower predilation rate and a higher incidence of intra- and postprocedure HD; furthermore, the decline in heart rate in the SCS procedure was higher in patients with intra- and postprocedure HD (P < 0.05). Right stenosis [odds ratio (OR) 1.67] and stent type (ev3) (OR 2.31) were confirmed as risk factors, and older age (> 70 years) was accompanied by a lower risk (OR 0.58; P < 0.05). The SCS procedure had a higher incidence of bradycardia and hypotension after 24 h and a longer duration of hypotension (P < 0.05). Stenosis (> 80%) (OR 1.68), the SCS procedure (OR 1.72), and alcohol intake (OR 2.38) were defined as risk factors. There was no difference in the complications or clinical endpoint events in either procedure, and the restenosis rate was lower in the TCS procedure (1.35% vs 5.42%).

CONCLUSION

Our results reveal that TCS has a lower incidence of HD and that intra- and postprocedure HD have different manifestations and risk factors.

Simultaneous internal carotid artery stenosis and ipsilateral anterior communicating artery saccular aneurysm treatment: a case report

The presence of ipsilateral aneurysm in the stenosis of the internal carotid artery is determined by computed tomography angiography in 1.8%-3.2% of cases. The literature describes the most varied options for treating this pathology: isolated or alternate, and now the method of simultaneous endovascular treatment - carotid stenting and endovascular embolization of aneurysm - is gaining popularity. We presented a clinical case of treatment of 61 women with critical stenosis (90%) and tortuosity of the internal carotid artery in combination with ipsilateral saccular aneurysm of the anterior connecting artery. The uniqueness of this case lies in the fact that a hybrid approach has been applied in the treatment of pathology, not previously described in the literature. The case is highlighting the potential complexity of concomitant vascular cervical and cerebral pathology and the necessity of surgical and endovascular team interactions to choose the appropriate methods of treatment.

Update on cerebral hyperperfusion syndrome

Cerebral hyperperfusion syndrome (CHS) is a clinical syndrome following a revascularization procedure. In the past decade, neurointerventional surgery has become a standard procedure to treat stenotic or occluded cerebral vessels in both acute and chronic settings, as well as endovascular thrombectomy in acute ischemic stroke. This review aims to summarize relevant recent studies regarding the epidemiology, diagnosis, and management of CHS as well as to highlight areas of uncertainty. Extracranial and intracranial cerebrovascular diseases in acute and chronic conditions are considered. The definition and diagnostic criteria of CHS are diverse. Although impaired cerebrovascular autoregulation plays a major role in the pathophysiology of CHS, the underlying mechanism is still not fully understood. Its clinical characteristics vary in different patients. The current findings on clinical and radiological presentation, pathophysiology, incidence, and risk factors are based predominantly on carotid angioplasty and stenting studies. Hemodynamic assessment using imaging modalities is the main form of diagnosis although the criteria are distinct, but it is helpful for patient selection before an elective revascularization procedure is conducted. After endovascular thrombectomy, a diagnosis of CHS is even more complex, and physicians should consider concomitant reperfusion injury. Management and preventative measures, including intensive blood pressure control before, during, and after revascularization procedures and staged angioplasty, are discussed in detail.

Perioperative Stroke

PURPOSE OF REVIEW

This review overviews perioperative stroke as it pertains to specific surgical procedures.

RECENT FINDINGS

As awareness of perioperative stroke increases, so does the opportunity to potentially improve outcomes for these patients by early stroke recognition and intervention. Perioperative stroke is defined to be any stroke that occurs within 30 days of the initial surgical procedure. The incidence of perioperative stroke varies and is dependent on the specific type of surgery performed. This chapter overviews the risks, mechanisms, and acute evaluation and management of perioperative stroke in four surgical populations: cardiac surgery, carotid endarterectomy, neurosurgery, and non-cardiac/non-carotid/non-neurological surgeries.

Fatal Subarachnoid Hemorrhage From Ruptured Intracerebral Aneurysm After Carotid Endarterectomy

Concomitant carotid stenosis with cerebral aneurysm is a rare entity with an incidence reported to be about 1.9-3.2%. The effect of carotid revascularization on pre-existing cerebral aneurysm, along with risk factors for aneurysmal rupture, is not fully understood. We report a 61-year-old man who underwent carotid endarterectomy (CEA) for symptomatic carotid stenosis, and 6 days post-operatively the patient suffered a fatal subarachnoid hemorrhage from the rupture of a known basilar artery aneurysm. This rare but potentially fatal complication of a ruptured cerebral aneurysm after CEA warrants a discussion on the management of concomitant pathology.

Neurologic complications in patients with carotid artery stenting

Objective

Carotid artery stenting is helpful in patients with carotid artery stenosis and is a common method of treatment. However, data on the neurological consequences that might arise from, especially Asian patients after CAS is not enough. The purpose of this study was to investigate the outcome and prognostic factors affecting CAS patients.

Methods

From January 2013 to June 2018 it was enrolled 97 patients who underwent CAS with severe carotid artery stenosis in a single institution. We retrospectively reviewed neurologic complications such as restenosis, ipsilateral or contralateral stroke, and hyperperfusion during the 6-month follow-up period.

Results

There were no complication occured during the procedure in all 97 patients. Neurologic complications occurred in 30 patients (30.9%) after the procedure, and ipsilateral stroke 6 (6.2%), contralateral stroke 9 (9.4%), restenosis 2 (2.1%) and hyperperfusion 13 respectively. One of them had died (1.0%), of which the rest were discharged after symptoms improve. On univariate analysis, DM and pre-op NIHSS score was associated with the risk of CAS complication, exclusively. On the binary logistic regression for risk factors, DM (OR 0.144, 95% CI [0.029-0.718]), history of radiotheraphy (OR 36.103, 95% CI [1.009-1291.789]) and preoperative NIHSS (OR 1.266, 95% CI [1.059-1.513]) showed independent risk factors associated with post procedural neurological complications, statistically.

Conclusion

Carotid artery stenting is a relatively safe and reliable long-term outcome for patients with carotid artery stenosis. However, careful observation should be taken after procedure immediately for any possible complications.

Posterior Reversible Encephalopathy Syndrome and Reversible Cerebral Vasoconstriction Syndrome: Distinct Clinical Entities with Overlapping Pathophysiology

The clinical and radiologic manifestations of posterior reversible encephalopathy syndrome and reversible cerebral vasoconstriction syndrome are reviewed. The relationship between these entities is discussed. A hypothesis of a common underlying pathophysiology is proposed and substantiated based on the current medical literature.

[Cerebral hyper perfusion syndrome after carotid artery stenting]

OBJECTIVE

To explore the risk factors, clinical characteristics, precaution and treatment of hyper perfusion syndrome (HPS) after carotid artery stenting (CAS).

METHODS

From September 2014 to March 2018, the clinical data of 226 patients with severe carotid stenosis (70%-99%) treated with carotid artery stenting (CAS)at Department of Interventional Radiology and Vascular Surgery, Peking University Third Hospital, were analyzed retrospectively．Five of them developed HPS after CAS．The relationship between the clinical baseline data, imaging characteristics, perioperative management and HPS were assessed.

RESULTS

In this group, 5 patients of them (2.21%, 5/226) developed HPS after CAS, and 2 patients of them (0.88%, 2/226) were hyper perfusion induced intracranial hemorrhage (HICH). The 5 patients consisted of 4 men and 1 woman whose age ranged from 58 to 74 years. The symptoms of HPS occurred within 4 hours to 3 days after CAS. Among the 5 cases, the clinical manifestations were that 2 cases with headache, 1 case with delirium,1 case with hemiparesis of left limbs, and 1 case with coma(died ultimately).The main manifestations of case 1 and case 2 were headache in the frontal parietal temporal region of the operative side, accompanied by nausea and vomiting. The symptoms were relieved after blood pressure lowering treatment and mannitol dehydration. The main manifestations of case 3 were excitement and delirium. The symptoms were relieved by a small dose of sedatives, also with blood pressure lowering treatment and mannitol dehydration. The initial symptoms of case 4 were excitement and delirium, accompanied by mild headache of the operative side, and hemiplegia of the contralateral limb occurred within a short time. The main manifestation of case 5 was severe headache and went into deep coma within a short time. This patient died of massive cerebral hemorrhage ultimately.

CONCLUSION

HPS is an uncommon but serious complication after CAS. Improving our understanding and heightening vigilance of HPS is necessary. The earlier diagnosis, the earlier treatment.

Comparison of the effect of sevoflurane or propofol anesthesia on the regional cerebral oxygen saturation in patients undergoing carotid endarterectomy: a prospective, randomized controlled study

Background

The monitoring of regional cerebral oxygen saturation (SrO₂) using near-infrared spectroscopy is useful method to detect cerebral ischemia during. Sevoflurane and propofol decrease cerebral metabolic rate (CMRO₂) in a similar manner, but the effects on the cerebral blood flow (CBF) are different. We hypothesized that the effects of sevoflurane and propofol on SrO₂ were different in patients with deficits of CBF. This study compared the effect of sevoflurane and propofol on SrO₂ of patients undergoing cerebral endarterectomy (CEA).

Method

Patients undergoing CEA were randomly assigned to the sevoflurane or propofol group (n = 74). The experiment was preceded in 2 stages based on carotid artery clamping. The first stage was from induction of anaesthesia to immediately before clamping of the carotid artery, and the second stage was until the end of the operation after clamping of the carotid artery. Oxygen saturation (SrO₂, SpO₂), haemodynamic variables (blood pressure, heart rate), respiratory parameters (end-tidal carbon dioxide tension, inspired oxygen tension), concentration of anesthetics, and anesthesia depth (bispectral index score) were recorded.

Results

During stage 1 period (before carotid artery clamping), the mean value of the relative changes in SrO₂ was higher (P = 0.033) and the maximal decrease in SrO₂ was lower in the sevoflurane group compared with the propofol group (P = 0.019) in the contralateral (normal) site. However, there is no difference in ipsilateral site (affected site). SrO₂ decreased after carotid artery clamping and increased after declamping, but the difference was not significant between two groups. Changes in mean arterial blood pressure was lower in sevoflurane group than propofol group after the carotid artery declamping (P = 0.048).

Conclusion

Propofol-remifentanil anesthesia was comparable with sevoflurane-remifentanil anesthesia in an aspect of preserving the SrO₂ in patients undergoing carotid endarterectomy.

Trial registration

Clinical Trials.gov identifier: NCT02609087, retrospectively registered on November 18, 2015.

Management of De Novo Carotid Stenosis and Postintervention Restenosis-Carotid Endarterectomy Versus Carotid Artery Stenting-a Review of Literature

The current literature indicates carotid endarterectomy (CEA) as the preferred treatment for symptomatic, moderate to severe carotid artery stenosis. However, recommendations for the management of acute tandem stenosis and complete occlusion, as well as postintervention restenosis of the carotid artery, remain controversial. Here, we review the literature evaluating these conditions and provide suggestions for clinical decision-making. Acute tandem stenosis or occlusion of the common and internal carotid arteries may be treated with angioplasty alone, reserving carotid artery stenting (CAS) or CEA for severe and complex cases. Patients who underwent CEA and developed ipsilateral restenosis may be subjected to angioplasty followed by CAS, which carries a lower risk of cranial nerve injury and subsequent restenosis of the artery. For post-CAS restenosis, current evidence recommends angioplasty and CAS for the management of moderate stenosis and CEA for severe stenosis of the carotid artery. Given the lack of level 1 evidence for the management of these conditions, the abovementioned recommendations may assist clinical decision-making; however, each case and its unique risks and benefits need to be assessed individually. Future studies evaluating and defining the risks and benefits of specific treatment strategies, such as CEA and CAS, in patients with acute tandem stenosis, occlusion, and postintervention restenosis of the carotid artery need to be conducted.

[Hibrid intervention for internal carotid artery stenosis and ipsilateral aneurysm of anterior communicating artery]

The presence of an ipsilateral aneurysm in stenosis of the internal carotid artery is determined by the findings of CT angiography in 1.8-3.2% of cases. The available literature has described a wide variety of treatment for this pathology: isolated or alternate, with a method of simultaneous endovascular treatment, i. e., carotid stenting and endovascular embolization of an aneurysm, currently gaining popularity. The major difficulties associated with therapeutic decision-making in this cohort of patients include stage-wise nature, temporal parameters, the need for removal of an intracranial aneurysm, and assessment of perioperative complications. A clinical case report presented herein is an example of a method of a hybrid approach, i. e., simultaneously performing carotid endarterectomy and endovascular embolization of an aneurysm. In certain cases (anatomical variants, structure of an atherosclerotic plaque, individual peculiarities), this approach is more justified than popularity-gaining simultaneous endovascular treatment.

Tandem cervical carotid stenting for stenosis with flow diversion embolisation for the treatment of intracranial aneurysms

Background

An estimated 2%–3% of the population harbour an intracranial aneurysm. Concomitant atherosclerotic cervical carotid disease is not uncommon. The management of these two entities remains a challenge within the field.

Case presentation

We report a single case of concomitant carotid stenosis and two ipsilateral unruptured intracranial aneurysms treated with a single-staged cervical carotid stenting and cerebral aneurysm embolisation with the Pipeline embolisation device.

Discussion

No consensus currently exists to guide endovascular treatment of intracranial aneurysms associated with asymptomatic ipsilateral stenosis. Here, we present a case of asymptomatic moderate carotid stenosis with two ipsilateral intracranial aneurysms and suggest carotid artery stenting takes procedural priority over aneurysm embolisation in single-stage treatment. The rationale for the sequence of neurointerventions is based on the tracking a robust distal access system beyond a stenotic proximal carotid lesion and stabilisation of the ulcerated plaque to avoid thromboembolic complications associated with plaque irritation during aneurysm embolisation. Additional cases and longer follow-up will be needed to further assess the efficacy of this technique.

Short-term Outcome of Straight vs Tapered Carotid Stenting for Symptomatic Carotid Artery Stenosis: A Prospective Study

PURPOSE

To investigate the short-term outcomes and complications of straight vs tapered carotid stent placement for patients with symptomatic carotid stenosis.

METHODS

A prospective study was conducted to examine if tapered carotid stents (TCS) performed better than straight carotid stents (SCS) in terms of complications and outcomes in patients with a unilateral, symptomatic, internal carotid artery stenosis ⩾70%. Between January 2014 and January 2016, 236 patients were screened; 88 were excluded, leaving 148 patients for 1:1 randomization to carotid artery stenting with either SCS or TCS. The data were analyzed for differences between the groups in terms of complications (hemodynamic depression, cerebral hyperperfusion syndrome, puncture site sequelae) and endpoint events (stroke, myocardial infarction, and death) at 30 days and 6 months.

RESULTS

Two patients in the TCS group underwent endarterectomy after allocation, leaving 72 patients (mean age 65.1±8.8 years; 59 men) in the TCS group for analysis vs 74 (mean age 65.0±7.9 years; 58 men) in the SCS group. The technical success was 100% in both groups. The incidence of hemodynamic depression (hypotension and bradycardia) after the procedures were higher in the SCS group (p=0.04), and the patients who underwent SCS procedures had longer hospital stays (p=0.01). There was no difference in the incidences of complications, myocardial infarction, mortality, or stroke at 30 days or 6 months between the SCS and TCS groups. The rates of restenosis (4% SCS vs 1% TCS) were similar (p=0.63); all restenoses were moderate (50%-70%).

CONCLUSION

When compared to straight stents, tapered carotid stents significantly decreased hemodynamic complications and hospital stay.

The middle-term outcome of carotid endarterectomy and stenting for treatment of ischemic stroke in Chinese patients

This study aims to investigate the complication and middle-term outcome of carotid endarterectomy (CEA) and carotid artery stenting (CAS) in Chinese patients, which was a retrospective case-control study and perioperative complications and 2-year end points were analyzed. Follow-up was done by a certified doctor, and restenosis was detected by ultrasound. Operation success rate were 100% in two groups. CAS showed the higher incidence rate of all stroke/TIA at 30days post-procedure (7.89% VS 1.85%, P = 0.038), odds ratio (OR) with 95% confidence interval, 4.54 (1.09–18.97), but there was no difference in the incidence rate of stroke subgroups, mortality and myocardial infarction between two groups. The higher incidence of hypertension with CEA (14.42% VS 5.26%, P = 0.012), OR: 2.90 (1.26–6.65) and hypotension with CAS (14.91% VS 1.85%, P = 0.001), OR: 0.11 (0.03–0.42). No difference in all stroke, ipsilateral stroke and mortality between two groups at 24 months post-procedures, however, the total incidence rate of stroke/death was higher in CAS (12.84% VS 4.72%, P = 0.036), OR: 2.98 (1.08,8.23). Higher restenosis rate of CAS was examined (13.76% VS 5.66%, P = 0.045), OR: 2.66 (1.02, 6.74). CAS and CEA showed a similar middle-term outcome, but CAS showed a higher incidence rate of stroke and restenosis after operation.

High Systolic Blood Pressure after Successful Endovascular Treatment Affects Early Functional Outcome in Acute Ischemic Stroke

BACKGROUND

Endovascular treatment (EVT) has been shown to significantly improve functional outcome in patients with acute large cerebral vessel occlusions. To date, no evidence-based recommendations on blood pressure management after successful EVT exist. Previous studies showed an association between high pre-EVT systolic blood pressure (SBP) and functional outcome, but do not answer the question on how to manage blood pressure after successful recanalization. The purpose of this study was to determine the role of blood pressure measurements as a predictor for early functional outcome in patients with successful EVT.

METHODS

Prospectively derived data from patients with acute large vessel occlusion within the anterior circulation and EVT was analyzed in this monocentric study. Mean systolic- and maximum SBP as well as SBP-peaks have been obtained for the first 24 h after successful EVT. Predictive value of SBP for discharge modified Rankin Scale (mRS) ≤2 has been investigated using logistic regression models.

RESULTS

From 168 patients with successful EVT, 74 (44%) had a favorable outcome with an mRS ≤2. Mean- (127 vs. 131 mm Hg, p = 0.035) and maximum SBP (157 vs. 169 mm Hg, p < 0.001) as well as the number of SBP-peaks (0 vs. 1.5, p = 0.004) were lower in patients with favorable outcomes. Multivariable logistic regression showed high mean- and maximum SBP to predict unfavorable outcomes. Cutoff mean SBP was 141 mm Hg and maximum SBP 159 mm Hg.

CONCLUSIONS

High SBP in the first 24 h after recanalization of acute anterior cerebral vessel occlusions is associated with unfavorable functional outcome. Interventional studies are needed to determine the role of SBP management as a modifiable parameter in the early phase after successful EVT.