In the End, It All Comes Down to the Beginning!

Free-Cell Area Impact on Stroke Prevention in Asymptomatic Patients Undergoing Carotid Artery Stenting: The "Carotid Artery sTenting And CeLl-area Impact on Stroke and Major Adverse events" (CATACLISMA) Multicenter Registry

PURPOSE

The study investigated the association between cell-stent area and cerebrovascular events incidence in asymptomatic patients undergoing carotid artery stenting (CAS).

MATERIALS AND METHODS

This is an observational, retrospective, multicenter, cohort study. Between 2012 and 2022, all patients undergoing primary CAS for severe asymptomatic carotid artery stenosis were evaluated. Three groups were defined on the basis of the cell area (open cell, OC; closed cell, CC; double layer, DL). Periprocedural primary outcomes were 30-day stroke, mortality, myocardial infarction (MI), and major adverse event (MAE, stroke/mortality composite outcome) rates. Follow-up primary outcomes included overall survival, stroke-free survival (SFS), freedom from ipsilateral stroke (FFiS), and freedom from stroke-related mortality (FF-SRM). Data were analyzed at short-term (1 year) and mid-term (2.5 years) period.

RESULTS

A total of 1096 CAS were considered (787 men, 71.8%, median age = 74 years). Technical success was achieved in 99.5% procedures. Periprocedural 30-day stroke rate was 1.5% (OC: 1.1%, CC: 2.3%, DL: 1%, p=0.27), mortality was 0.7% (OC: 1.1%, CC: 0.3%, DL: 0.5%, p=0.35), and no MI was recorded. The MAE rate was 2.1% (OC: 2%, CC: 2.6%, DL: 1.5%, p=0.66). Median follow-up was 46 months. At 1 and 2.5 years, estimated overall survival was 96.1% and 91% (p=0.41), SFS was 99.1% and 98.2% (p=0.007, CC stroke rates 2.9% and 4.2% at timepoints), FFiS was 99.4% and 99% (p=0.014, CC FFiS rates 1.7% and 2.6% at timepoints) and FF-SRM was 99.5% and 99% (p=0.28). During follow-up, no stroke events occurred in DL group. CC design showed higher rates of any (4.2%) and ipsilateral stroke (2.6%) within 2.5 years.

CONCLUSION

In asymptomatic patients undergoing CAS, the contemporary overall stroke incidence is 1.5%. No statistical differences were observed in terms of 30-day stroke incidence among groups. The closed free-cell area showed higher rates of any and ipsilateral stroke within 2.5 years. The DL stents may offer the best available performances in terms of mid-term stroke prevention.

CLINICAL IMPACT

The study analyzed the contemporary results of carotid artery stenting (CAS) focusing on the impact of cell-stent area on peri- and post-operative cerebrovascular events in a multicenter real-world experience. In asymptomatic patients undergoing CAS the contemporary overall stroke incidence is 1.5%. No statistical differences were observed in terms of 30-day stroke incidence among groups. The closed free-cell area showed higher rates of any and ipsilateral stroke within 2.5 years. DL stents may offer the best available performances in terms of mid-term stroke prevention.

The ClearSight System for Postoperative Arterial Blood Pressure Monitoring After Carotid Endarterectomy: A Validation Study

BACKGROUND

The majority of postoperative events in patients undergoing carotid endarterectomy (CEA) are of hemodynamic origin, requiring preventive strict postoperative arterial blood pressure (BP) control. This study aimed to assess whether BP monitoring with noninvasive beat-to-beat ClearSight finger BP (BPCS) can replace invasive beat-to-beat radial artery BP (BPRAD) in the postoperative phase.

METHODS

This study was a single-center clinical validation study using a prespecified study protocol. In 48 patients with symptomatic carotid artery stenosis, BPCS and BPRAD were monitored ipsilateral in a simultaneous manner during a 6-hour period on the recovery unit following CEA. Primary endpoints were accuracy and precision of BP derived by ClearSight (Edward Lifesciences, Irvine, CA) vs. the reference standard (Arbocath 20 G, Hospira, Lake Forest, IL) to investigate if BPCS is a reliable noninvasive alternative for BP monitoring postoperatively in CEA patients. Validation was guided by the standard set by the Association for Advancement of Medical Instrumentation (AAMI), considering a BP-monitor adequate when bias (precision) is <5 (8) mm Hg. Secondary endpoint was percentage under- and overtreatment, defined as exceedance of individual postoperative systolic BP threshold by BPRAD or BPCS in contrast to BPCS or BPRAD, respectively.

RESULTS

The bias (precision) of BPCS compared to BPRAD was -10 (13.6), 8 (7.2) and 4 (7.8) mm Hg for systolic, diastolic and mean arterial pressure (MAP), respectively. Based on BPCS, undertreatment was 5.6% and overtreatment was 2.4%; however, percentages of undertreatment quadrupled for lower systolic BP thresholds.

CONCLUSIONS

Noninvasive MAP, but not systolic and diastolic BP, was similar to invasive BPRAD during postoperative observation following CEA, based on AAMI criteria. However, as systolic BP is currently leading in postoperative monitoring to adjust BP therapy on, BPCS is not a reliable alternative for BPRAD.

Variation in perioperative cerebral and hemodynamic monitoring during carotid endarterectomy

BACKGROUND

Hemodynamic disturbances cause half of the perioperative strokes following carotid endarterectomy (CEA). Guidelines strongly recommend strict pre- and postoperative blood pressure (BP) monitoring in CEA patients, but do not provide firm practical recommendations. Although in the Netherlands 50 centres perform CEA, no national protocol on perioperative hemodynamic, and cerebral monitoring exists. To assess current monitoring policies of all Dutch CEA-centres, a national survey was conducted.

METHODS

Between May and July 2017 all 50 Dutch CEA-centres were invited to complete a 42-question survey addressing perioperative hemodynamic and cerebral monitoring during CEA. Nonresponders received a reminder after 1 and 2 months. By November 2017 the survey was completed by all centres.

RESULTS

Preoperative baseline BP was based on a single bilateral BP-measurement at the outpatient-clinic in the majority of centres (n = 28). In 43 centres (86%) pre-operative monitoring (transcranial Doppler (TCD, n = 6), electroencephalography (EEG, n = 11), or TCD + EEG (n = 26)) was performed as a baseline reference. Intraoperatively, large diversity for type of anaesthesia (general: 45 vs. local [LA]:5) and target systolic BP (>100 mm hg - 160 mm hg [n = 12], based on preoperative outpatient-clinic or admission BP [n = 18], other [n = 20]) was reported. Intraoperative cerebral monitoring included EEG + TCD (n = 28), EEG alone (n = 13), clinical neurological examination with LA (n = 5), near-infrared spectroscopy with stump pressure (n = 1), and none due to standard shunting (n = 3). Postoperatively, significant variation was reported in standard duration of admission at a recovery or high-care unit (range 3-48 hr, mean:12 hr), maximum accepted systolic BP (range >100 mm hg - 180 mm Hg [n = 32]), postoperative cerebral monitoring (standard TCD [n = 16], TCD on indication [n = 5] or none [n = 24]) and in timing of postoperative cerebral monitoring (range directly postoperative - 24 hr postoperative; median 3 hr).

CONCLUSIONS

In Dutch centres performing CEA the perioperative hemodynamic and cerebral monitoring policies are widely diverse. Diverse policies may theoretically lead to over- or under treatment. The results of this national audit may serve as the baseline dataset for development of a standardized and detailed (inter)national protocol on perioperative hemodynamic and cerebral monitoring during CEA.

Results of carotid artery stenting. Lessons learned in a Belgian 'real world' practice

OBJECTIVE/BACKGROUND

Carotid artery stenting (CAS) is a valuable solution for the treatment of carotid artery stenosis in a high-risk patient population for carotid endarterectomy (CEA). In literature however, there are concerns about the death and stroke rates of CAS in the 'real world' practice. Since Belgium is a small country with a broad offer of medical care, and there is no reimbursement for CAS, only small numbers of patients can be treated per vascular department.

METHODS

In our department 45 CAS were performed from January 2006 until May 2018. Patient characteristics, indication for treatment and choice of treatment, minor stroke, major stroke and death rates were analyzed retrospectively.

RESULTS

Of these patients 8/45 (18%) had a symptomatic carotid artery stenosis and 37/45 (82%) had an asymptomatic stenosis. A total minor stroke rate of 3/45 (6.6%) was recorded, but no major stroke (0%) or death (0%). Of the 37 patients who were asymptomatic at the start, 1 suffered a minor stroke (1/37, 2.7%) peri-operatively.

CONCLUSION

Real world data from a low volume center show that CAS performed in patients with high risk for CEA yields acceptable outcome that is comparable to the literature. Since CAS is a delicate procedure we advice to centralize the procedure to an dedicated experienced interventionalist and to perform rigorous quality control of your 'real world' data.

In vitro performance of echoPIV for assessment of laminar flow profiles in a carotid artery stent

Purpose: Detailed blood flow studies may contribute to improvements in carotid artery stenting. High-frame-rate contrast-enhanced ultrasound followed by particle image velocimetry (PIV), also called echoPIV, is a technique to study blood flow patterns in detail. The performance of echoPIV in presence of a stent has not yet been studied extensively. We compared the performance of echoPIV in stented and nonstented regions in an in vitro flow setup.

Approach: A carotid artery stent was deployed in a vessel-mimicking phantom. High-frame-rate contrast-enhanced ultrasound images were acquired with various settings. Signal intensities of the contrast agent, velocity values, and flow profiles were calculated.

Results: The results showed decreased signal intensities and correlation coefficients inside the stent, however, PIV analysis in the stent still resulted in plausible flow vectors.

Conclusions: Velocity values and laminar flow profiles can be measured in vitro in stented arteries using echoPIV.

[Carotid endarterectomy in a patient with bilateral restenosis of stents in internal carotid arteries]

The article deals with the results of surgical treatment of a male patient presenting with bilateral restenosis of stents in the internal carotid arteries 11 years after carotid angioplasty with stenting. Described herein are literature reports reflecting the state of the art of the problem, scarcity of studies, as well as some important issues still unresolved. Defined are the main indications for and contraindications to performing this type of reconstruction. The main stages of the operation are demonstrated. This is followed by describing a method of intraoperative protection of the brain, including invasive measurement of retrograde pressure. Besides, the most optimal terms of carrying out the second stage of treatment were determined, eventually demonstrating efficacy and safety of carotid endarterectomy for correction of this condition.

Short-Term Double Layer Mesh Stent Patency for Emergent or Elective Carotid Artery Stenting

Background and Purpose—

Novel double layer micromesh stents have recently been introduced for treatment of patients with significant carotid stenosis. Strict evaluation of safety and patency of such novel devices is required both in elective and in emergency interventions. We report a single center experience with double layer mesh stents for carotid artery revascularization.

Methods—

Consecutive patients who underwent carotid artery stenting with a double layer mesh stent between June 2015 and September 2018 in our tertiary vascular referral center were included. Treatment indications were emergent carotid artery stenting for intracranial or extracranial carotid stenosis in patients undergoing intraarterial thrombectomy for acute ischemic stroke in the anterior circulation, or elective carotid artery stenting for significant symptomatic or asymptomatic stenosis. End points were postprocedural thrombotic stent occlusion and procedural stroke or death.

Results—

Fifty-four patients were included; 27 were treated for acute stroke with intracranial and extracranial (tandem) lesions and 27 for elective stenting. Follow-up imaging was available for 9/27 (33%) patients with acute stroke, and 19/27 (70%) electively treated patients. Five stent occlusions occurred, of which 2 were symptomatic with clinical deterioration within one day. Another patient deteriorated on postprocedural day one, but imaging of the carotids was not performed, and the stent turned out occluded on the 30-day duplex. All stent occlusions occurred in patients treated for acute stroke.

Conclusions—

This study suggests that occlusion of novel double layer mesh stents occurs in a considerable proportion of carotid artery stenting procedures performed in the emergency setting for acute stroke, with occlusion-related symptoms in half the cases. Future prospective studies should clarify the role of double layer mesh stents in this high-risk patient population.

Carotid artery stenting: Current state of evidence and future directions

Both carotid endarterectomy (CEA) and carotid artery stenting (CAS) are common treatments for carotid artery stenosis. Several randomized controlled trials (RCTs) have compared CEA to CAS in the treatment of carotid artery stenosis. These studies have suggested that CAS is more strongly associated with periprocedural stroke; however, CEA is more strongly associated with myocardial infarction. Published long-term outcomes report that CAS and CEA are similar. A reduction in complications associated with CAS has also been demonstrated over time. The symptomatic status of the patient and history of previous CEA or cervical radiotherapy are significant factors when deciding between CEA or CAS. Numerous carotid artery stents are available, varying in material, shape and design but with minimal evidence comparing stent types. The role of cerebral protection devices is unclear. Dual antiplatelet therapy is typically prescribed to prevent in-stent thrombosis, and however, evidence comparing periprocedural and postprocedural antiplatelet therapy is scarce, resulting in inconsistent guidelines. Several RCTs are underway that will aim to clarify some of these uncertainties. In this review, we summarize the development of varying techniques of CAS and studies comparing CAS to CEA as treatment options for carotid artery stenosis.

Long-term outcomes of stenting and endarterectomy for symptomatic carotid stenosis: a preplanned pooled analysis of individual patient data

BACKGROUND

The risk of periprocedural stroke or death is higher after carotid artery stenting (CAS) than carotid endarterectomy (CEA) for the treatment of symptomatic carotid stenosis. However, long-term outcomes have not been sufficiently assessed. We sought to combine individual patient-level data from the four major randomised controlled trials of CAS versus CEA for the treatment of symptomatic carotid stenosis to assess long-term outcomes.

METHODS

We did a pooled analysis of individual patient-level data, acquired from the four largest randomised controlled trials assessing the relative efficacy of CAS and CEA for treatment of symptomatic carotid stenosis (Endarterectomy versus Angioplasty in Patients with Symptomatic Severe Carotid Stenosis trial, Stent-Protected Percutaneous Angioplasty of the Carotid Artery versus Endarterectomy trial, International Carotid Stenting Study, and Carotid Revascularization Endarterectomy versus Stenting Trial). The risk of ipsilateral stroke was assessed between 121 days and 1, 3, 5, 7, 9, and 10 years after randomisation. The primary outcome was the composite risk of stroke or death within 120 days after randomisation (periprocedural risk) or subsequent ipsilateral stroke up to 10 years after randomisation (postprocedural risk). Analyses were intention-to-treat, with the risk of events calculated using Kaplan-Meier methods and Cox proportional hazards analysis with adjustment for trial.

FINDINGS

In the four trials included, 4775 patients were randomly assigned, of whom a total of 4754 (99·6%) patients were followed up for a maximum of 12·4 years. 21 (0·4%) patients immediately withdrew consent after randomisation and were excluded. Median length of follow-up across the studies ranged from 2·0 to 6·9 years. 129 periprocedural and 55 postprocedural outcome events occurred in patients allocated CEA, and 206 and 57 for those allocated CAS. After the periprocedural period, the annual rates of ipsilateral stroke per person-year were similar for the two treatments: 0·60% (95% CI 0·46-0·79) for CEA and 0·64% (0·49-0·83) for CAS. Nonetheless, the periprocedural and postprocedural risks combined favoured CEA, with treatment differences at 1, 3, 5, 7, and 9 years all ranging between 2·8% (1·1-4·4) and 4·1% (2·0-6·3).

INTERPRETATION

Outcomes in the postprocedural period after CAS and CEA were similar, suggesting robust clinical durability for both treatments. Although long-term outcomes (periprocedural and postprocedural risks combined) continue to favour CEA, the similarity of the postprocedural rates suggest that improvements in the periprocedural safety of CAS could provide similar outcomes of the two procedures in the future.

FUNDING

None.

Meta-analysis of the costs of carotid artery stenting and carotid endarterectomy

BACKGROUND

Carotid artery stenting (CAS) is currently associated with an increased risk of 30-day stroke compared with carotid endarterectomy (CEA), whereas both interventions seem equally durable beyond the periprocedural period. Although the clinical outcomes continue to be scrutinized, there are few data summarizing the costs of both techniques.

METHODS

A systematic search was conducted in MEDLINE, Embase and Cochrane databases in August 2016 identifying articles comparing the costs or cost-effectiveness of CAS and CEA in patients with carotid artery stenosis. Combined overall effect sizes were calculated using random-effects models. The in-hospital costs were specified to gain insight into the main heads of expenditure associated with both procedures.

RESULTS

The literature search identified 617 unique articles, of which five RCTs and 12 cohort studies were eligible for analysis. Costs of the index hospital admission were similar for CAS and CEA. Costs of the procedure itself were 51 per cent higher for CAS, mainly driven by the higher costs of devices and supplies, but were balanced by higher postprocedural costs of CEA. Long-term cost analysis revealed no difference in costs or quality of life after 1 year of follow-up.

CONCLUSION

Hospitalization and long-term costs of CAS and CEA appear similar. Economic considerations should not influence the choice of stenting or surgery in patients with carotid artery stenosis being considered for revascularization.

Carotid endarterectomy for treatment of carotid in-stent restenosis: long-term follow-up results and surgery experiences from one single centre

Objective

Few studies have reported the surgical treatment of carotid in-stent restenosis (ISR), more data and longer follow-up are needed. We describe the surgical treatment of ISR by standard carotid endarterectomy (CEA) with stent removal, including long-term follow-up in 10 patients from our centre.

Methods

Ten patients from our centre who underwent CEA with stent removal for ISR were retrospectively analysed, including nine symptomatic and one asymptomatic ISR of at least 70% with mean age 67.3, the median time between carotid artery stenting and CEA was 17 months (range, 2–54 months).

Results

Standard CEA with stent removal was performed in all 10 patients without much technical difficulty (9 male and 1 female, mean age 67.3). Two cases were performed in hybrid operation room. There were a total of three complications that happened in three patients (30%) respectively. An asymptomatic dissecting aneurysm was formed on the petrous internal carotid artery in one patient who was followed up without intervention. In the second case, dissection occurred in the arterial wall distal to the site of the stent after stent removal revealed by intraoperative angiography, and another stent was implanted. The patient sustained temporary hypoglossal nerve dysfunction postoperatively. The third patient suffered cerebral hyperperfusion with complete recovery when discharged. No neurological complications occurred in other seven patients. After follow-up of 25 months (range, 11–54 months), one patient died of rectal cancer without ischaemic attack and restenosis 4 years postoperation; in one patient occurred recurrent symptomatic restenosis (90%) 1 year later; all other patients remained asymptomatic and without recurrent restenosis (>50%) by follow-up carotid ultrasound or CT angiography.

Conclusion

It seems that CEA with stent removal is a reasonable choice, by experienced hand, for symptomatic ISR with higher but acceptable complications. The indication of stent removal for asymptomatic ISR needs further observation.