Influence of Stent Type on Hemodynamic Depression after Carotid Artery Stent Placement

Persistent Hemodynamic Depression After Carotid Artery Stenting: A Review and Update

According to the American Heart Association, ischemic stroke is the second leading cause of death globally and is responsible for approximately 11% of deaths. Carotid endarterectomy (CEA) is the standard treatment for moderate or severe extracranial internal carotid artery (ICA) stenoses. With the development of materials and technology in neurointervention, the Centers for Medicare and Medicaid Services (CMS) have proposed that carotid artery stenting (CAS) can serve as an alternative treatment for CEA. As CAS is widely used worldwide, comorbidities, especially persistent hemodynamic depression (PHD) and stroke, have attracted public attention. In this review, we summarized the current advances in PHD after CAS. A better understanding of CAS-related PHD may inspire the design of potential prognostic and therapeutic tools.

Hemodynamic depression after carotid surgery: Incidence, risk factors and outcomes

INTRODUCTION

Hemodynamic Depression (HD) characterized by hypotension and bradycardia is a complication of carotid surgery due to direct autonomic stimulation in the carotid sinus. The authors believe the incidence of HD is high and possibly related to major cardiac complications.

METHODS

Analysis of patient records during admissions for carotid surgery between January 2014 and December 2018 in two hospitals. HD was defined as bradycardia or hypotension in the first 24 postoperative hours. Bradycardia was defined as heart rate < 50bpm; hypotension as systolic blood pressure < 90 mmHg, continuous use of vasopressors, or a drop in SBP > 20% compared to preoperative values. Myocardial infarction, stroke, and cardiovascular death were defined as adverse events.

RESULTS

Overall, 237 carotid surgeries (178 endarterectomies, 59 angioplasties) were studied, and the global incidence of HD was 54.4% (hypotension in 50.2%, bradycardia in 11.0%, and hypotension and bradycardia in 6.8%). The independent predictors of HD were asymptomatic carotid stenosis (OR = 1.824; 95% CI 1.014-3.280; p = 0.045), endovascular surgery (OR = 3.319; 95% CI 1.675-6.576; p = 0.001) and intraoperative hypotension or bradycardia (OR = 2.144; 95% CI 1.222-3.762; p = 0.008). Hypotension requiring continuous vasopressor infusion was the only factor independently associated with adverse cardiovascular events (OR = 5.504; 95% CI 1.729-17.529; p = 0.004).

DISCUSSION/CONCLUSION

Incidence of Hemodynamic Depression after carotid surgery is high and independently associated with surgical technique, symptomatic repercussion of the carotid stenosis, and intraoperative hypotension or bradycardia. Hypotension requiring the continuous infusion of vasopressors was independently associated with the occurrence of MACE.

Predisposing Factors and Management of Hemodynamic Depression Following Carotid Artery Stenting

Carotid artery stenting (CAS) involves dilatation of carotid bulb which can trigger a series of neuronal responses resulting in hemodynamic depression that might influence the outcome of the procedure. This is a frequent but underdiagnosed complication of CAS. Although it is mild, transient and self-limiting in majority of cases, it can result in significant morbidity and mortality if persistent. Neurologists should be aware of the predisposing factors and management of this common complication. In patients who present with stroke following carotid stenting, neurologists should be aware of hypoperfusion secondary to hemodynamic depression as a cause of stroke apart from the stent thrombosis and occlusion.

Incidence and predictors of prolonged hemodynamic depression after carotid artery stenting: Yet another benefit of statins?

OBJECTIVES

We aimed to assess the incidence and predictors of prolonged hemodynamic depression (PHD) after carotid artery stenting (CAS).

METHODS

We retrospectively analyzed data from 216 CAS procedures performed in 207 patients (156 male; median and interquartile range (IQR) of age 68 (62-73) yr) between July 2012 and October 2020. PHD was defined as hypotension (systolic blood pressure ≤ 90 mmHg) and/or bradycardia (heart rate < 60 bpm) lasting >1 h.

RESULTS

The incidence of PHD was 25.9%. At multivariate analysis, asymptomatic lesions (OR: 2.43, 95% CI (1.16-5.06), p: 0.018), the stenosis proximity (<10 mm) to bifurcation (OR: 2.94, 95% CI (1.34-6.43), p: 0.007) and implantation of a Protege stent (OR: 2.93, 95% CI (1.14-7.53), p: 0.025) were independent risk factors, while statin usage (OR: 0.48, 95% CI (0.24-0.95), p: 0.036) was an independent protective factor for PHD after CAS.

CONCLUSIONS

Patients with asymptomatic lesions and stenosis close to the bifurcation are more prone to PHD. The type of the stent selected significantly influences the risk of PHD. Further prospective randomized studies are warranted to investigate the possible protective role of statins against PHD after CAS.

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.

A meta-analysis of the effect of stent design on clinical and radiologic outcomes of carotid artery stenting

OBJECTIVE

Procedural characteristics, including stent design, may influence the outcome of carotid artery stenting (CAS). A thorough comparison of the effect of stent design on outcome of CAS is thus warranted to allow for optimal evidence-based clinical decision making. This study sought to evaluate the effect of stent design on clinical and radiologic outcomes of CAS.

METHODS

A systematic search was conducted in MEDLINE, Embase, and Cochrane databases in May 2018. Included were articles reporting on the occurrence of clinical short- and intermediate-term major adverse events (MAEs; any stroke or death) or radiologic adverse events (new ischemic lesions on postprocedural magnetic resonance diffusion-weighted imaging [MR-DWI], restenosis, or stent fracture) in different stent designs used to treat carotid artery stenosis. Random effects models were used to calculate combined overall effect sizes. Metaregression was performed to identify the effect of specific stents on MAE rates.

RESULTS

From 2654 unique identified articles, two randomized, controlled trials and 66 cohort studies were eligible for analysis (including 46,728 procedures). Short-term clinical MAE rates were similar for patients treated with open cell vs closed cell or hybrid stents. Use of an Acculink stent was associated with a higher risk of short-term MAE compared with a Wallstent (risk ratio [RR], 1.51; P = .03), as was true for use of Precise stent vs Xact stent (RR, 1.55; P < .001). Intermediate-term clinical MAE rates were similar for open vs closed cell stents. Use of open cell stents predisposed to a 25% higher chance (RR, 1.25; P = .03) of developing postprocedural new ischemic lesions on MR-DWI. No differences were observed in the incidence of restenosis, stent fracture, or intraprocedural hemodynamic depression with respect to different stent design.

CONCLUSIONS

Stent design is not associated with short- or intermediate-term clinical MAE rates in patients undergoing CAS. Furthermore, the division in open and closed cell stent design might conceal true differences in single stent efficacy. Nevertheless, open cell stenting resulted in a significantly higher number of subclinical postprocedural new ischemic lesions detected on MR-DWI compared with closed cell stenting. An individualized patient data meta-analysis, including future studies with prospective homogenous study design, is required to adequately correct for known risk factors and to provide definite conclusions with respect to carotid stent design for specific subgroups.

Multivariable Analysis of Patients With Severe Persistent Postprocedural Hypotension After Carotid Artery Stenting

Purpose: To assess the incidence and predictors of severe, persistent postprocedural hypotension (PPH) after carotid artery stenting (CAS). Materials and Methods: A total of 146 patients (mean age 72.8 years; 104 men) who underwent 160 CAS procedures using a standardized protocol at 3 vascular centers were retrospectively analyzed. The primary endpoint was postprocedural hypotension, defined as a reduction in systolic blood pressure (SBP) >40 mm Hg from baseline or an SBP of <90 mm Hg sustained for >1 hour after CAS. Potential prognostic factors for postprocedural hypotension were identified and subjected to logistic regression analyses; outcomes are presented as the odds ratios (ORs) with 95% confidence intervals (CIs). Results: PPH developed in 36 (24.7%) patients after 37 (23.1%) CAS procedures. These patients had significantly longer intensive care unit and hospital stays than those who did not develop hypotension (p<0.001). PPH was associated with severe lesion calcification (OR 6.28, 95% CI 1.81 to 21.98, p=0.004) and contrast volume (OR 1.02, 95% CI 1.01 to 1.02, p<0.001). A 4-fold increase in the risk of PPH (OR 4.22, 95% CI 1.38 to 13.33, p=0.012) was found between the embolic protection device most associated with PPH (Angioguard) and the device least associated with PPH (Emboshield NAV6). A similar trend was also observed for the Precise vs Xact stents (OR 6, 95% CI 2.08 to 17.6, p=0.001). Bootstrapped multivariable modeling identified the Precise stent and contrast volume as significant predictors of persistent postprocedural hypotension. Further investigation of the contrast volume revealed associations with sex, severe calcification, arch type, previous coronary artery bypass surgery, and primary stenting, suggesting that the contrast volume reflects the complexity of the procedure. Conclusion: The complexity of the procedure and type of stent may play a role in the development of postprocedural hypotension after CAS.

Cerebral Hemodynamic Variations in the Early Stage after Carotid Artery Stenting in Patients with and without Near Occlusion

BACKGROUND

To evaluate the unclear cerebral hemodynamic variations in patients with and without near occlusion (NO) in hours after carotid artery stenting (CAS) by transcranial Doppler (TCD).

METHODS

Data of 56 patients (11 patients with carotid artery NO and 45 patients with severe stenosis without NO) who underwent unilateral CAS were analyzed. All patients underwent TCD or transcranial color-code Doppler monitoring before CAS and again at one and three hours after the procedure. We compared bilateral middle cerebral artery peak systolic velocity (MCA-PSV), pulsatility index (PI), and blood pressure (BP) data between the two groups.

RESULTS

Ipsilateral MCA-PSV increased relative to baseline in the stenosis group at one hour (97 ± 30 vs. 84 ± 23 cm/s, 16%, P < 0.001) and three hours (96 ± 28 vs. 84 ± 23 cm/s, 15%, P < 0.001) after CAS. Corresponding increases were distinctly higher in the NO group than in the stenosis group at one hour (116 ± 37 vs. 80 ± 29 cm/s, 51%, P < 0.001) and three hours (113 ± 39 vs. 80 ± 29 cm/s, 46%, P = 0.001) after CAS, whereas BP decreased similarly between the two groups. The ipsilateral PI increased postsurgically in both groups, whereas contralateral MCA-PSV was unaltered.

CONCLUSIONS

CAS can induce a significant increase in PSV and PI in ipsilateral MCA within three hours in patients with NO or severe stenosis but absent NO. The increment of ipsilateral MCA-PSV was greater in patients with NO. TCD can facilitate BP control in the early stage after CAS in patients with NO.

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.

Effect of Open- vs Closed-Cell Stent Design on Periprocedural Outcomes and Restenosis After Carotid Artery Stenting: A Systematic Review and Comprehensive Meta-analysis

Purpose:To compare periprocedural complications and in-stent restenosis rates associated with open- vs closed-cell stent designs used in carotid artery stenting (CAS). Methods: A systematic search was conducted to identify all randomized and observational studies published in English up to October 31, 2017, that compared open- vs closed-cell stent designs in CAS. Identified studies were included if they reported the following outcomes: stroke, transient ischemic attack (TIA), myocardial infarction (MI), hemodynamic depression, new ischemic lesions detected on imaging, and death within 30 days, as well as the incidence of in-stent restenosis. A random-effects model meta-analysis was employed. Model results are reported as the odds ratio (OR) and 95% confidence interval (CI). The I2 statistic was used to assess heterogeneity. Results: Thirty-three studies (2 randomized trials) comprising 20, 291 patients (mean age 71.3±3.0 years; 74.6% men) were included. Patients in the open-cell stent group had a statistically significant lower risk of restenosis ⩾40% (OR 0.42, 95% CI 0.19 to 0.92; I2=0%) and ⩾70% (OR 0.23, 95% CI 0.10 to 0.52; I2=0%) at a mean follow-up of 24 months. No statistically significant differences were identified for periprocedural stroke, TIA, new ischemic lesions, MI, hemodynamic depression, or death within 30 days after CAS. Sensitivity analysis of the 2 randomized controlled trials only did not point to any significant differences either. Conclusion: Use of open-cell stent design in CAS is associated with a decreased risk for restenosis when compared to the closed-cell stent, without significant differences in periprocedural outcomes.

Analysis of Hemodynamic Changes in Early Stage after Carotid Stenting by Transcranial Doppler-A Preliminary Study

BACKGROUND

Cerebral hyperperfusion syndrome or hemodynamic instability, caused by the hemodynamic changes, often occur within 6 hr after carotid artery stenting (CAS) The postprocedure cerebral hemodynamic change in the early phase, <6 hr after CAS, is largely unknown. In this study, we evaluated the cerebral hemodynamic changes in patients after CAS using transcranial Doppler (TCD).

METHODS

From January 2013 to July 2014, medical records of 61 patients who underwent CAS were reviewed retrospectively. Among them, 44 patients had TCD examination before CAS, 1-2 and 3-4 hr after CAS. In the TCD examination, middle cerebral artery (MCA) peak systolic velocity (PSV) and pulsatility index (PI) on the ipsilateral and contralateral sides were measured. Blood pressure, MCA PSV, and PI data were collected and analyzed from the 44 patients who had valid TCD examinations.

RESULTS

Blood pressure was 148.4 ± 14.5 mm Hg before CAS: 124.5 ± 13.8 mm Hg 1-2 hr after CAS, and 121.6 ± 12.6 mm Hg 3-4 hr after CAS. On the ipsilateral side, the MCA PSV increased from 85.7 ± 22.8 cm/s before CAS to 101.1 ± 27.1 cm/s (19.9%, P < 0.001) 1-2 hr after CAS, and 99.7 ± 27.0 cm/s (18.2%, P < 0.001) 3-4 hr after CAS. There was no significant difference in MCA PSV between 1-2 and 3-4 hr after CAS (P = 0.200). The PI increased from 0.871 ± 0.167 before CAS to 0.941 ± 0.205 (P = 0.022) 1-2 hr after CAS, and 0.954 ± 0.218 (P = 0.010) 3-4 hr after CAS. On the contralateral side, there was no statistically significant PSV increase in the MCA following CAS.

CONCLUSIONS

CAS may induce a significant increase in PSV and PI in the ipsilateral MCA within 4 hr. The MCA PSV increased significantly higher than that on the contralateral side. The PSV had no significant change between 1-2 and 3-4 hr after CAS.

Selective-versus-Standard Poststent Dilation for Carotid Artery Disease: A Systematic Review and Meta-Analysis

BACKROUND

The safety and efficacy of standard poststent angioplasty in patients undergoing carotid artery stent placement have not been well-established.

PURPOSE

We conducted a systematic review of the literature to evaluate the safety and efficacy of carotid artery stent placement and analyzed outcomes of standard-versus-selective poststent angioplasty.

DATA SOURCES

A systematic search of MEDLINE, EMBASE, Scopus, and the Web of Science was performed for studies published between January 2000 and January 2015.

STUDY SELECTION

We included studies with >30 patients describing standard or selective poststent angioplasty during carotid artery stent placement.

DATA ANALYSIS

A random-effects meta-analysis was used to pool the following outcomes: periprocedural stroke/TIA, procedure-related neurologic/cardiovascular morbidity/mortality, bradycardia/hypotension, long-term stroke at last follow-up, long-term primary patency, and technical success.

DATA SYNTHESIS

We included 87 studies with 19,684 patients with 20,378 carotid artery stenoses. There was no difference in clinical (P = .49) or angiographic outcomes (P = .93) in carotid artery stent placement treatment with selective or standard poststent balloon angioplasty. Both selective and standard poststent angioplasty groups had a very high technical success of >98% and a low procedure-related mortality of 0.9%. There were no significant differences between both groups in the incidence of restenosis (P = .93) or procedure-related complications (P = .37).

LIMITATIONS

No comparison to a patient group without poststent dilation could be performed.

CONCLUSIONS

Our meta-analysis demonstrated no significant difference in angiographic and clinical outcomes among series that performed standard poststent angioplasty and those that performed poststent angioplasty in only select patients.

Hemodynamic changes and baroreflex sensitivity associated with carotid endarterectomy and carotid artery stenting

Atherosclerotic carotid lesion is a major cause of stroke which accounts for up to 20% of ischemic stroke. Aggressive treatment of carotid stenosis may prevent stroke. Currently, carotid endarterectomy (CEA) and carotid artery stenting (CAS) are the first-line treatments for severe carotid stenosis. CEA is superior to medical therapy in preventing stroke and cardiovascular death. CAS has emerged as an alternative to CEA in recent years due to its less invasive nature. However, both CEA and CAS may be associated with adverse hemodynamic changes as well as a variation of carotid baroreflex sensitivity. There is no consensus on which of these two methods is more advantageous concerning the procedure-related hemodynamic changes. This article reviews the hemodynamic changes and baroreflex sensitivity after CEA and CAS.

Role of Stent Selection in the Incidence of Persisting Hemodynamic Depression After Carotid Artery Stenting

Purpose: To investigate the possible role of stent selection and procedure-related vessel diameter changes in the development of persisting hemodynamic depression (PHD) and to demonstrate the effectiveness and safety of permanent pacemaker implantation in patients with refractory PHD. Methods: Data from 584 procedures performed in 542 patients (398 men; mean age 67.3 years) between 2008 and 2011 using Wallstent, Precise, and Xact stents in a nonrandomized fashion were analyzed retrospectively. Cardiovascular risk factors and lesion, stent, and balloon characteristics were collected, and the pre- and postprocedure diameters of the common carotid artery (CCA) and internal carotid artery were measured. PHD was defined as any episode of hypotension (systolic blood pressure <90 mm Hg) and/or bradycardia (heart rate <60/min) lasting >6 hours. Risk factors for PHD were sought using logistic regression analyses; the results are presented as the odds ratio (OR) and 95% confidence interval (CI). Results: The incidence of PHD was 37.0% (216/584). Refractory PHD was encountered in 9 patients; among these, 6 were successfully treated with pacemaker implantation. A history of prior ipsilateral carotid endarterectomy (OR 0.44, 95% CI 0.22 to 0.87, p=0.019) and the presence of a contralateral high-grade stenosis (OR 0.12, 95% CI 0.02 to 0.95, p=0.045) were independent protective factors, while calcification (OR 1.5, 95% CI 1.03 to 2.18, p=0.034), involvement of the carotid bulb (OR 2.56, 95% 1.62 to 4.03, p<0.001), and implantation of a nitinol stent (adjusted OR 1.62, 95% CI 1.12 to 2.34, p=0.011) were independent risk factors for developing PHD after carotid artery stenting. The ratio of the post-/preprocedure CCA diameter (p=0.002), the stent to CCA diameter ratio (p=0.009), and the presence of residual stenosis (p=0.009) were significantly higher in the PHD group. Conclusion: Stent selection and procedure-related changes in vessel diameter may have an influence on the development of PHD. Permanent pacemaker implantation is an effective treatment option in patients with refractory PHD.

Incidence of hemodynamic depression after carotid artery stenting using different self-expandable stent types

The rates of hemodynamic depression (HD) and thromboembolism were compared in 95 carotid artery stenting (CAS) procedures performed in 87 patients with severe carotid artery stenosis using self-expandable braided Elgiloy stents (Wallstent) in 52 and slotted-tube Nitinol stents (Precise) in 43 procedures. The blood pressure, pulse rate, and neurological signs were recorded at short intervals during and after CAS. All patients underwent diffusion-weighted magnetic resonance imaging within 5 days after the procedure. The incidences of hypotension, bradycardia, and both were 17.9%, 3.2%, and 11.6%, respectively. The rate of postprocedural HD was 23.1% with Wallstent and 44.2% with Precise; the difference was significant (p = 0.025). No patient manifested major cardiovascular disease after CAS. Diffusion-weighted magnetic resonance imaging revealed thromboembolism after 26.9% and 34.9% of Wallstent and Precise stent placement procedures, respectively; the difference was not significant. The type of self-expandable stent placed may affect the risk of procedural HD in patients undergoing CAS. Postprocedural HD was resolved successfully by the administration of vasopressors and by withholding antihypertensive agents.