Postprocedural hypotension after carotid artery stent placement: predictors and short- and long-term clinical outcomes

Evaluation of the self-expanding effect of carotid stents in the early postoperative period

PURPOSE

To evaluate the expansion effect of self-expandable stents during the first week after carotid artery stenting (CAS) procedure and to examine the variation of the effect according to the carotid plaque type.

METHODS

Seventy stenotic carotid arteries of 69 patients were stented by using self-expanding Wallstents with diameters of 7 and 9 mm, after detection of stenosis and plaque type by Doppler ultrasonography. Post-stent aggressive ballooning was avoided and residual stenosis rates were measured with digital subtraction angiography. After the stenting procedure, the caudal, narrowest, and cranial diameters of stents were measured with ultrasonography at 30 min, first day and first week. Stent diameter increase and change according to plaque type were evaluated. Two-way repeated measure ANOVA test was used for statistical analysis.

RESULTS

A significant increase was observed in the mean stent diameter in the three stent regions (caudal, narrow, and cranial) from the 30th minute to the first and seventh days (p < 0.001). The most prominent stent expansion occurred in the cranial and narrow segments within the first day. In the narrow stent region; Stent diameter increase between 30th minute-first day, 30th minute-first week, and first day-first week were all significant (p < 0.001). At 30 min, first day, and first week, no significant difference was detected between plaque type and stent expansion in caudal, narrow, and cranial regions (p = 0.286).

CONCLUSION

We think that keeping the lumen patency limited to 30% residual stenosis after CAS procedure by applying minimal post-stenting balloon dilatation and leaving the remaining lumen expansion to the self-expanding feature of the Wallstent might be a sensible approach in order to avoid embolic events and excessive carotid sinus reactions (CSR).

Patients with Prior Exposure to a Combination of Statins & Angiotensin-Converting Enzyme Inhibitors (ACE-Is)/Angiotensin Receptor Blockers (ARBs) Have Better Outcomes after Carotid Revascularization than Patients with Prior Exposure to Statins Alone: A MultiCenter Analysis

BACKGROUND

Statin use has been studied and confirmed to have a beneficial impact on perioperative carotid endarterectomy (CEA) and carotid artery stenting (CAS) outcomes. The benefits of Angiotensin-converting enzyme inhibitors (ACE-I) in hypertension, ischemic heart disease, heart failure, diabetes mellitus, and renal disease are well-known; however, the impact of continuing or withholding ACE-Is/angiotensin receptor blockers (ARBs) on CEA and CAS outcomes is not addressed well in the literature. This study aimed to evaluate the impact of preoperative statin use combined with ACE-Is/ARBs in patients undergoing CEA or CAS on mortality and morbidity using a multi-institutional database.

METHODS

Using the data of all patients who underwent carotid artery revascularization, including CEA, transcarotid artery revascularization, and transfemoral carotid artery stenting from 2016 to 2021 in the Vascular Quality Initiative data, we determined as our primary outcome 30-day mortality/stroke after carotid revascularization based on periop exposure to statins alone, or the combination of statins and ACE-Is/ARBs. Secondary outcomes were postop myocardial infarction and postop congestive heart failure. Poisson regression with robust variance was used to determine postop outcomes comparing the combination of statin and ACE-Is/ARBs group with statins alone group.

RESULTS

A total of 131,285 patients were included in the study, with 59,860 (46%) patients receiving statin only, and 71,425 (54%) receiving both statin and ACE-Is/ARBs preoperatively. Both patient groups differed significantly in preop clinical and demographic characteristics. After adjusting for potential confounders, the statins plus ACE-I/ARB group had a 12% lower risk of postop mortality/stroke (Incident Rate Ratio comparing Statin/ACE group to Statins Only group [IRR] 0.88, 95% confidence interval 0.81-0.95, P = 0.001), 18% lower risk of postop congestive heart failure (IRR 0.82, 95% CI 0.68-0.98, P = 0.029), and similar risk of postop myocardial infarction (IRR 1.05 95% confidence interval 0.91-1.20, P = 0.54) compared to the statin-only group.

CONCLUSION

Statins combined with ACE-Is/ARBs perioperatively offer better protection compared to statins alone in patients undergoing carotid revascularization surgery. We recommend the continuation of ACE-Is/ARBs use in patients undergoing carotid revascularization, especially if they have concurrent hypertension. Further prospective studies are needed to evaluate the benefit of adding ACE-Is/ARBs.

Peri-procedural variables and outcomes of long-period hemodynamic instability after carotid artery angioplasty and stenting

OBJECTIVES

The aim of this study is to identify the peri-procedural risk factors and outcomes of hemodynamic instability (HI) after carotid artery stenting (CAS).

METHODS

A single-center, retrospective study was performed in 168 patients who underwent CAS procedure between September 2017 and September 2020. The presence of HI, as defined by hypertension (systolic blood pressure >160 mmHg), hypotension (systolic blood pressure <90 mmHg), and/or bradycardia (heart rate <60 bpm), was recorded. Long-period HI was defined as persistent HI lasting more than 24 h. Patient demographics, comorbidities, peri-procedural variables, and risk factors were recorded. Clinical outcomes including cerebral hyperperfusion syndrome, hemorrhage, transient ischemic attack (TIA), stroke, myocardial infarction, and mortality within 30 days of the procedure were evaluated. Logistic regression was used to analyze the independent risk factors of long-period HI following CAS.

RESULTS

Among 168 patients (mean age, 68.2 ± 8.3 years; 81.5% male), the frequency of post-procedural long-period HI was noted in 42 patients (25.0%). Male was prone to experience HI (odds ratio, 9.156, p = 0.021). Aggressive inflation pressure (>7 atm) and 5 mm balloon for pre-dilatation were risk factors of long-period HI (OR, 7.372, p = 0.035; OR, 3.527, p = 0.023). Intraoperative peak blood pressure and larger-sized stents remained independent predictors for the development of HI (OR, 1.043, p = 0.027, and OR, 1.973, p = 0.015). Patients with prolonged HI were more likely to suffer TIA and stroke compared to other patients and significant difference was found in the occurrence of TIA (p < 0.05). Non-significance was found in mortality rate and other outcomes.

CONCLUSIONS

CAS-induced HI occurs in a considerable percentage while several peri-procedural variables are determined as independent predictors to develop long-period HI. Patients with prolonged HI are associated with increased risk of neurologic events and thus standardized intervention as well as management of long-period HI are of critical importance during clinical process.

Predictors of hemodynamic instability during and persistent after carotid artery stenting

OBJECTIVES

The risk factors for post-carotid artery stenting severe hemodynamic instability remain elusive. This study aimed to identify the predictors of severe hemodynamic instability during and persisted after carotid artery stenting.

MATERIALS AND METHODS

Consecutive patients who underwent carotid artery stenting for extracranial carotid artery stenosis at a single-center between September 2018 and July 2021 were retrospectively assessed. The predictive factors of severe hemodynamic instability intraoperation and post-operation were analyzed.

RESULTS

Among the 139 patients included, 63 experienced severe hemodynamic instability, with 45 and 18 cases occurring intra and postoperatively, respectively. Persistent was observed in 21 patients. Smoke exposure (odds ratio [OR], 2.38; p=0.039), carotid bifurcation stenosis (OR, 0.91; p=0.018), and large-diameter balloon (>4 mm) dilatation (OR, 11.95; p<0.001) were identified as independent risk factors for hemodynamic instability at any stage of carotid artery stenting. Intraoperatively, large-diameter balloon (>4 mm) dilatation was associated with an increased risk of hemodynamic instability occurrence (OR, 4.67; p=0.01), whereas general anesthesia (OR, 0.19; p=0.001) and a longer distance from the stenosis to the carotid bifurcation (OR, 0.89; p=0.01) were negatively associated with hemodynamic instability. Furthermore, smoking exposure (OR, 3.73; p=0.03), large diameter balloon dilatation (OR, 6.12; p=0.032), distance from stenosis to bifurcation (OR, 0.85; p=0.047) and long-stent (40 mm) implantation (OR, 0.84 [95% confidence interval, 0.74-0.95]; p=0.007) could independently predict persistent hemodynamic instability.

CONCLUSION

Patients with a smoking history, lesions near the carotid bulb, or dilatation using a large-diameter balloon were most likely to suffer severe hemodynamic instability. General anesthesia can protect against severe hemodynamic instability only intraoperatively. Long-term stent implantation may reduce persistent hemodynamic instability.

Low left atrial volume is an independent predictor of persistent hypotension after carotid artery stenting

BACKGROUND

Persistent hypotension (PH) after carotid artery stenting (CAS) is a relatively common complication; however, it is unclear which patients are more likely to experience this phenomenon. Recently, lower left atrial (LA) volume was associated with vasovagal syncope, which has a similar neurological mechanism to hypotension after CAS. This study aimed to investigate whether LA volume can predict PH after CAS.

METHODS

This single center retrospective analysis used data from 316 patients who had undergone CAS between March 2013 and February 2021. After the exclusion of urgent CAS, 212 procedures (202 patients) with transthoracic echocardiograms were included. The procedures were divided among two groups according to the presence or absence of PH for more than 1 hour after CAS.

RESULTS

The mean age of the patients was 73.0±7.5 years. PH was observed during 52 (24.5%) procedures. The PH group exhibited a lower LA volume index (LAVI) than the no-PH group (29.7±9.1 vs 37.7±12.5 mL/m2, respectively; p<0.001). The area under the receiver operating characteristic curve was 0.716. The optimal cut-off value was 33.5 mL/m2 (sensitivity 0.750, specificity 0.625). Multiple logistic regression analysis showed that LAVI <33.5 mL/m2 was an independent predictor for PH after CAS (OR 4.950, 95% CI 2.190 to 11.200; p<0.001). Preoperative hydration was negatively associated with PH (OR 0.235, 95% CI, 0.070 to 0.794; p=0.020).

CONCLUSIONS

A lower LA volume can predict PH after CAS, and preoperative hydration may prevent PH after CAS.

Hemodynamic Instability Predicts In-Hospital and One-Year Mortality After TransCarotid Artery Revascularization and TransFemoral Carotid Stenting

OBJECTIVES

Blood pressure fluctuations are a common hemodynamic alteration following carotid artery stenting either with transfemoral (TFCAS) or transcarotid (TCAR) approach and are thought to be related to alteration in baroreceptor function due to angioplasty and stent expansion. These fluctuations are particularly worrisome in the high-risk patient population referred for CAS. This study aims to evaluate the outcomes of patients who required the administration of intravenous blood pressure medication (IVBPmed) for hypotension or hypertension after CAS.

METHODS

All patients undergoing carotid revascularization in the Vascular Quality Initiative (VQI) database between 2016-2021 were included. we compared outcomes of patients who required postoperative IVBPmed to treat hyper- or hypotension with normotensive patients. In-hospital outcomes were compared using multivariable logistic regression. One-year outcomes were assessed using Kaplan-Meier survival and multivariable Cox proportional hazard regression analyses.

RESULTS

We identified 38,510 patients undergoing CAS (57.7% TCAR and 42.3% TFCAS), of which, 30% received IVBPmed for treatment of either postoperative hypertension (12.6%) or hypotension (16.4%). In multivariable analysis, postoperative hypotension was associated with a higher risk of stroke, death, or MI (OR: 3.1, 95%CI (2.6-3.6), P<.001), stroke or death (OR: 2.9, 95%CI (2.4-3.5), P<.001), stroke (OR: 2.6, 95%CI (2.1-3.2), P<.001), death (OR: 3.5, 95%CI (2.6-4.8), P<.001), MI (OR: 4.7, 95%CI (3.3-6.7), P<.001), and bleeding (OR: 1.96, 95%CI (1.4-2.7), P<.001) compared to normotensive patients. Postoperative hypertension was associated with a higher risk of stroke, death, or MI (3.6, 95%CI (3-4.4), P<.001), stroke or death (OR: 3.3, 95%CI (2.7-4.1), P<.001), stroke (OR: 3.7, 95%CI (3-4.7), P<.001), death (OR: 2.7, 95%CI (1.9-3.9), P<.001), MI (OR: 5.7, 95%CI (3.9-8.3), P<.001), and bleeding (OR: 1.9, 95%CI (1.4-2.7), P<.001) compared to normotensive patients.

CONCLUSIONS

Postoperative hypertension or hypotension requiring IVBPmed after CAS is associated with an increased risk of in-hospital stroke, death, MI, and bleeding. Postoperative hypertension is associated with worse survival at one year. This study indicates that the need for IVBPmed after CAS is not benign, therefore, these patients necessitate aggressive perioperative medical management and safe techniques to avoid hypo and hypertension. Close follow-up and continue medical management is needed to maximize these patients' survival.

Treatment results of carotid artery stenting in a developing country

OBJECTIVE

The purpose of this study was to investigate the details of minor complications of carotid artery stenting in a developing country.

METHODS

This was a retrospective, single-center study conducted on the target group consisting of 65 symptomatic patients who underwent carotid artery stenting. We assessed technical success rate, periprocedural complication within 30 days (hypotension, bradycardia, acute kidney injury, vasospasm, a transient ischemic attack, stroke, myocardial infarction, and death), and the differences between groups with and without complications.

RESULTS

Minor periprocedural complications occurred in 15 patients. In all, 8 (12.3%) had transient hypotension, 6 (9.2%) had bradycardia, 7 (10.7%) had acute kidney injury, 2 (3.1%) had vasospasm, and 1 (1.5%) had transient ischemic attack. A greater rate of minor complications was observed in women (p=0.051).

CONCLUSION

The results of the carotid artery stenting procedures performed in a developing country were acceptable.

Carotid artery stenosis concomitant with severe aortic stenosis treated by combination of staged angioplasty and transcatheter aortic valve implantation: A case report

Background:

When severe aortic stenosis (AS) is concomitant with carotid stenosis, carotid artery stenting (CAS) will become a high-risk procedure because baroreceptor reflex-induced bradycardia and hypotension may cause irreversible circulatory collapse. When carotid stenosis-related misery perfusion is present, the risk of cerebral hyperperfusion syndrome increases after carotid revascularization. We report a case of severe carotid disease concomitant with severe AS successfully treated by a combination of staged angioplasty (SAP) and transcatheter aortic valve implantation (TAVI).

Case Description:

An 86-year-old man presented with transient deterioration of mental status and sluggish responsiveness continuous from the previous day. Magnetic resonance imaging of the brain revealed a right putaminal infarction, occlusion of the right internal carotid artery (ICA), and severe stenosis of the left ICA. Severe AS was diagnosed and single-photon emission computed tomography showed misery perfusion at the bilateral ICA territories. We performed a staged treatment consisting of SAP for the left carotid stenosis and TAVI. A first-stage carotid angioplasty was performed, followed by TAVI 2 weeks later and second-stage CAS 1 week after that. There were no apparent periprocedural complications throughout the clinical course.

Conclusion:

Combining SAP and TAVI may be an effective treatment option for severe carotid stenosis with misery perfusion concomitant with severe AS.

Role of Renin-Angiotensin-Aldosterone System Inhibition in Patients Undergoing Carotid Revascularization

Background

Previous data suggest that using renin‐angiotensin‐aldosterone system inhibitors (RAASIs) improves survival in patients with cardiovascular diseases. We sought to investigate the association of different patterns of use of RAASIs on perioperative and 1‐year outcomes following carotid revascularization.

Methods and Results

We investigated patients undergoing carotid revascularization, either with carotid endarterectomy or transfemoral carotid artery stenting, in the VQI (Vascular Quality Initiative) VISION (Vascular Implant Surveillance and Interventional Outcomes Network) data set between 2003 and 2018. We divided our cohort into 3 groups: (1) no history of RAASI intake, (2) preoperative intake only, and (3) continuous pre‐ and postoperative intake. The final cohort included 73 174 patients; 44.4% had no intake, 50% had continuous intake, and 5.6% had only preoperative intake. Compared with continuous intake, preoperative and no intake were associated with higher odds of postoperative stroke (odds ratio [OR], 1.7 [95% CI, 1.5–1.9]; P<0.001; OR, 1.1 [95% CI, 1.03–1.2]; P=0.010); death (OR, 4.8 [95% CI, 3.8–6.1]; P<0.001; OR, 1.9 [95% CI, 1.6–2.2]; P<0.001); and stroke/death (OR, 2.05 [95% CI, 1.8–2.3]; P<0.001; OR, 1.2 [95% CI, 1.1–1.3]; P<0.001), respectively. At 1 year, preoperative and no intake were associated with higher odds of stroke (hazard ratio [HR], 1.4 [95% CI, 1.3–1.6]; P<0.001; HR, 1.15, [95% CI, 1.08–1.2]; P<0.001); death (HR, 1.7 [95% CI, 1.5–1.9]; P<0.001; HR, 1.3 [95% CI, 1.2–1.4]; P<0.001); and stroke/death (HR, 1.5 [95% CI, 1.4–1.7]; P<0.001; HR, 1.2 [95% CI, 1.17–1.3]; P<0.001), respectively.

Conclusions

Compared with subjects discontinuing or never starting RAASIs, use of RAASIs before and after carotid revascularization was associated with a short‐term stroke and mortality benefit. Future clinical trials examining prescribing patterns of RAASIs should aim to clarify the timing and potential to maximize the protective effects of RAASIs in high‐risk vascular patients.

Relationship between annular calcification of plaques in the carotid sinus and perioperative hemodynamic disorder in carotid angioplasty and stenting

OBJECTIVE

To investigate the correlation between annular plaque calcification in the carotid sinus and perioperative hemodynamic disorder (HD) in carotid angioplasty and stenting (CAS).

METHODS

The clinical data of 49 patients undergoing CAS due to narrowing of the carotid sinus were retrospectively analyzed. All patients had preoperative carotid computed tomography angiography (CTA) and were divided into HD and non-HD groups based on the occurrence of HD in the perioperative period of CAS. HD was defined as persistent bradycardia (heart rate < 60 beats per min) or persistent hypotension (systolic blood pressure < 90 mmHg) in the perioperative period and lasting for at least 1 h. The baseline data, including the degree of carotid artery stenosis, plaque length, plaque thickness, calcified plaque morphologies (i.e., plaque circumferential angle: < 90° defined as dotted calcification; 90°-180° defined as arcuate calcification; > 180° defined as annular calcification), contralateral carotid artery conditions, balloon diameter, and stent types, were compared between the two groups. Binary logistic regression was used to analyze the risk factors for the occurrence of HD.

RESULTS

Among the 49 patients undergoing CAS, 14 (28.57%) developed perioperative HD, and 35 did not. Annular calcification was more common in the patients in the HD group than in the non-HD group. No significant differences in the probabilities of dotted and arcuate calcifications were found between the two groups (p > 0.05). The duration of continuous dopamine consumption in the HD group was 9-71 h. The average hospital stay of the HD group (10.14 ± 4.17 days) was significantly longer than that of the non-HD group (6.57 ± 1.9 days; p < 0.001). Patients in the HD group had significantly more pronounced lumen stenosis (p = 0.033) and longer plaque length (p = 0.034) than those in the non-HD group. After adjusting for age and sex, multivariate regression analysis showed that the presence of annular plaque calcification was an independent predictor of HD (odds ratio: 7.68, 95% confidence interval: 1.46-40.37, p = 0.016).

CONCLUSIONS

The occurrence of annular plaque calcification in the carotid sinus was an independent risk factor for perioperative HD in CAS. Preoperative carotid CTA assists with the early identification of high-risk patients who may develop HD.

Blood Pressure Variability Can Predict Carotid Sinus Reaction After Carotid Stenting

BACKGROUND

Carotid stenting has become an important treatment for carotid disease. Carotid sinus reaction (CSR), a complication which is not uncommon and affects the outcome of carotid stenting. We investigated the predictors of CSR, including blood pressure variability and heart rate variability (BPV and HRV, respectively).

METHODS

We enrolled patients who underwent carotid stenting. CSR was defined as any episode of systolic blood pressure (SBP) <90 mm Hg or heart rate (HR) <60 beats/min after stent deployment or balloon inflation. BPV and HRV were measured before stent insertion and were represented by coefficient of variation (CoV) and SD. Multivariable logistic regression was performed to predict CSR.

RESULTS

Among the 176 patients, 61 (34.7%) patients showed CSR. Blood pressure and HR were measured 14 times before carotid stenting on average. The risk of CSR was independently associated with the use of longer stent (odds ratio: 1.08, 95% confidence interval: 1.00-1.16, P = 0.042) and increased SBP SD (1.07 [1.00-1.14], P = 0.048). Moreover, when the SBP parameter changed to SBP CoV, total stent length (1.08 [1.00-1.16], P = 0.042) and SBP CoV (1.12 [1.02-1.23], P = 0.023) were associated with the occurrence of CSR.

CONCLUSIONS

The use of a longer stent and increased SBP variability before carotid stent insertion were associated with the risk of CSR after carotid stenting. Underlying autonomic dysregulation may increase the risk of CSR during carotid stenting. SBP variability before carotid stenting might be considered a predictor of CSR.

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.

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.

Carotid revascularization improves cognitive function in patients with asymptomatic carotid artery stenosis

OBJECTIVE

To investigate cognitive changes after carotid revascularization in elderly patients with asymptomatic carotid artery stenosis. We also compared cognitive outcomes of carotid endarterectomy with stenting in asymptomatic patients.

METHODS

From April 2019 to December 2019, patients with ≥70% asymptomatic carotid stenosis who were treated with CEA or CAS were recruited for this study. The Montreal cognitive assessment (MoCA) instrument was used to evaluate cognitive function preoperatively and postoperatively at 3, 6, and 12 months. The incidence of ipsilateral ischemic cerebrovascular events and restenosis were analyzed within 12 months.

RESULTS

In 50 patients treated with CEA or CAS, baseline cognitive function was not different between CEA and CAS groups (P > 0.05). There was no difference in the incidence of ipsilateral ischemic cerebrovascular events and restenosis within the first 12 months between the two groups. There was a significant improvement in the total MoCA score, scores of attention, and delayed recall at 3, 6 and 12 months after revascularization compared with scores at baseline (all p<0.001). At 12 months, scores of cube copying and clock drawing were significantly improved (P=0.014, P=0.020). The clock drawing score was improved at 12 months after CAS compared with CEA (P=0.040).

CONCLUSIONS

Carotid revascularization has a beneficial effect on cognition in asymptomatic patients within 12 months of the procedure. Compared with CEA, CAS show improved test scores of executive functioning by 1 year.

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.

Is there any relationship between carotid bifurcation geometry and hemodynamic depression after carotid stenting and angioplasty?

BACKGROUND

Hemodynamic depression (HD) is a condition that can be encountered after carotid stenting (CAS) and carotid angioplasty (CAP) due to manipulation of the carotid sinus. The aim of this study was to evaluate whether the carotid bifurcation geometry and angles, or changes in angles, were associated with this HD in patients undergoing CAS and CAP.

METHODS

Sixty-two patients with a mean age of 71.1±7.4 years, who underwent CAS and CAP for carotid stenosis were included in the study. HD was defined as periprocedural hypotension (systolic blood pressure <90 mmHg) or bradycardia (heart rate <60 bpm). The effect of carotid bifurcation geometry, plaque morphology and risk factors on subsequent development of HD was analyzed with binary logistic regression models. ICA-CCA angle was measured from digital subtraction angiographies (DSA) before and after stent deployment by two radiologists. Interobserver agreement was calculated.

RESULTS

Periprocedural HD was seen in 22 (35.5%) patients. Extension of carotid lesion to bulbus, preoperative internal carotid artery (ICA) angle, postoperative angular changes, pre-op systolic blood pressure, balloon-to-artery ratio and HD were significantly correlated. A significant difference was observed between the angle of ICA before and after the procedure between the patients with HD and those without HD.

CONCLUSIONS

Carotid anatomy and geometry may enhance the risk of HD independent of other factors and may be of help in very early identification of patients at high risk of developing HD after CAS and CAP.

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.

Safety of simultaneous bilateral carotid artery stenting for bilateral carotid artery stenosis

BACKGROUND

Bilateral carotid artery stenting (BCAS) is often performed in two stages (staged BCAS) but it is also an option to be performed in one stage (simultaneous BCAS). To confirm the safety of simultaneous BCAS, we retrospectively analyzed perioperative and postoperative course of simultaneous BCAS compared with staged BCAS.

MATERIALS AND METHODS

Patients with symptomatic stenosis of ≥50% or asymptomatic stenosis of ≥80% of bilateral carotid arteries underwent BCAS. Procedure time, symptomatic ischemic complications, presence/absence of high-intensity spots on postoperative diffusion-weighted image, duration of postoperative hospital stays and 30 days outcome of patients performed with simultaneous BCAS (group A, 8 patients with 16 stenotic lesions (8 procedures)) were compared with those of staged BCAS (group B, 4 patients with 8 stenotic lesions (8 procedures)).

RESULTS

In groups A and B, procedure time was 146.0 ± 53.8 and 103.5 ± 39.4 min; intraoperative hypotension was observed in 62.5% and 50.0%; postoperative hypotension occurred in 37.5% and 50.0%; diffusion-weighted image showed high-intensity spots in 37.5% and 12.5%; and duration of postoperative hospital stays was 5.1 ± 1.8 and 5.3 ± 2.3 days. No patients suffered symptomatic ischemic complications. In simultaneous BCAS, there was a tendency that procedure time was longer and high-intensity spots on postoperative diffusion-weighted image was more frequent, but there was no increase in symptomatic ischemic complications and duration of hospital stays compared to staged BCAS.

CONCLUSIONS

Safety of simultaneous BCAS may not be inferior to staged BCAS. In terms of duration of hospital stays, simultaneous BCAS can be superior to staged BCAS for patients with bilateral carotid artery stenosis.

Bradycardia and Asystole in Patients Undergoing Symptomatic Chronically Occluded Internal Carotid Artery Recanalization

BACKGROUND

Reports have emerged describing the successful endovascular recanalization of the chronically occluded internal carotid artery (COICA). The impact this restoration of flow has on the sensitive carotid sinus baroreceptors has not been previously described. In this manuscript, we present the largest COICA surgical series to date, with a specific focus on perioperative heart rate abnormalities.

METHODS

Patient demographics were obtained, and the COICAs were radiographically classified based on the anatomic distribution of the stenosis and collateral flow. Thirty-six patients had a total of 37 COICA revascularization procedures.

RESULTS

A total of 23 patients had intraprocedural bradycardia during balloon angioplasty. Three patients went into transient asystole during the procedure, and 2 of these patients had symptomatic bradycardia with ischemic cerebral changes, 1 of which required permanent pacemaking. All other patients had immediate resolution of their bradycardia, asystole, and neurologic symptoms immediately following balloon deflation and pharmaceutical management. There was a statistically significant difference in the observed proportion of bradycardic patients among COICA classifications (P = 0.014). There was no statistically significant difference in mean age between patients with bradycardia and those without (aged 63.36 vs. 67.71 years, P = 0.2265).

CONCLUSIONS

Bradycardia associated with angioplasty of the carotid bulb was observed in the majority of patients receiving COICA revascularization. A small percentage of these patients were symptomatic. Our results suggest that carotid sinus baroreceptors remain active while residing in a complete arterial occlusion, and close monitoring is necessary during balloon angioplasty of the proximal COICA.

Technical improvements in carotid revascularization based on the mechanism of procedural stroke

The benefit of carotid revascularization in patients with severe carotid artery stenosis is hampered by the risk of stroke due to the intervention itself. The risk of periprocedural strokes is higher for carotid artery stenting (CAS) as compared to carotid endarterectomy (CEA). Over the past years, the pathophysiological mechanism responsible for periprocedural stroke seems to unfold step by step. Initially, all procedural strokes were thought to be the result of technical errors during surgical repair: cerebral ischemia due to clamping time of the carotid artery, cerebral embolization of atherosclerotic debris due to manipulation of the atheroma or thrombosis of the artery. Following improvements in surgical techniques, technical skills, new intraoperative monitoring technologies such as angioscopy, and the results of the first large clinical randomized controlled trials (RCT) it was believed that most periprocedural strokes were of thromboembolic nature, while a large part of these caused by technical error. Nowadays, analyses of underlying pathophysiological mechanisms of procedural stroke make a clinically relevant distinction between intra-procedural and postprocedural strokes. Intra-procedural stroke is defined as hypoperfusion due to clamping (CEA) or dilatation (CAS) and embolization from the carotid plaque (both CEA and CAS). Postprocedural stroke can be caused by thrombo-embolisation but seems to have a primarily hemodynamic origin. Besides thrombotic occlusion of the carotid artery, cerebral hyperperfusion syndrome (CHS) due to extensively increased cerebral revascularization is the most reported pathophysiological mechanism of postprocedural stroke. Multiple technical improvements have attempted to lower the risk of periprocedural stroke. The introduction of antiplatelet therapy (APT) has significantly reduced the risk of thromboembolic events in patients with carotid stenosis. Over the years, recommendations regarding APT changed. While for a long time APT was discontinued prior to surgery because of a fear of increased bleeding risk, nowadays continuation of APT during carotid intervention (aspirin monotherapy or even dual APT including clopidogrel) is found to be safe and effective. In CAS patients, dual APT up to three months' postprocedural is considered best. Stent design and cerebral protection devices (CPD) for CAS procedure are continuously under development. Trials have suggested a benefit of closed-cell stent design over open-cell stent design in order to reduce procedural stroke, while the benefit of CPD during stenting is still a matter of debate. Although CPD reduce the risk of procedural stroke, a higher number of new ischemic brain lesions detected on diffusion weighted imaging was found in patients treated with CPD. In patients undergoing CEA under general anesthesia, adequate use of cerebral monitoring (EEG and transcranial Doppler [TCD]) has reduced the number of intraoperative stroke by detecting embolization and thereby guiding the surgeon to adjust his technique or to selectively shunt the carotid artery. In addition, TCD is able to adequately identify and exclude patients at risk for CHS. For CAS, the additional value of periprocedural cerebral monitoring to prevent strokes needs urgent attention. In conclusion, this review provides an overview of the pathophysiological mechanism of stroke following carotid revascularization (both CAS and CEA) and of the technical improvements that have contributed to reducing this stroke risk.

Long-Term Hemodynamic Effects After Carotid Artery Revascularization

Objective:

The baroreceptor at the carotid body plays an important role in hemodynamic autoregulation. Manipulation of the baroreceptor during carotid endarterectomy (CEA) or radial force from carotid artery angioplasty and/or stenting (CAS) may cause both intraoperative and postoperative hemodynamic instability. The purpose of this study is to evaluate the long-term effects of CEA and CAS on blood pressure (BP), heart rate (HR), and subsequent changes on antihypertensive medications.

Methods:

A retrospective chart review was performed to identify patients who underwent CEA or CAS between 2009 and 2015 at a single tertiary care institution. Baseline demographics and comorbidities were recorded. Operative details of the carotid artery endarterectomy and the use of balloon angioplasty during the CAS were analyzed. Hemodynamic parameters such as BP, HR, and antihypertensive medication requirement were evaluated at 3, 6, 12, 24, and 36 months.

Results:

A total of 289 patients were identified. The average age was 70.6 years old, and males constituted 64.0%. All patients had moderate (>50%) to severe (>70%) carotid stenosis. Of those, 111 (40.5%) patients were symptomatic. Systolic BP (mm Hg) of CAS and CEA were similar over the entire follow-up period. Heart rate (beats/min) remained stable postoperatively. A reduced number of antihypertensive medications was observed in the CAS cohort during the first postoperative year when compared to the preoperative baseline: 2.03 at preop, 1.77 ( P < .01) at 3 months, 1.78 ( P = .02) at 6 months, 1.77 ( P = .02) at 12 months, 1.86 ( P = .09) at 24 months, and 2.03 ( P = =.50) at 36 months. Logistic regression analysis identified that CAS (odds ratio [OR]: 2.52, confidence interval [CI]: 1.09-5.83) and multiple (>2) antihypertensive medication use at baseline (OR: 5.89, CI: 2.62-13.26) were predictors for a reduction in the number of antihypertensive medications following carotid revascularization.

Conclusion:

Surgical intervention for carotid stenosis poses a risk of postoperative hemodynamic dysregulation. Although postoperative BP and HR remained relatively stable after both CAS and CEA, the number of postoperative antihypertensive medications was reduced in the CAS cohort for the first postoperative year when compared to baseline. Patients with multiple antihypertensive agents undergoing CAS should have close postoperative BP monitoring and should be monitored for a possible reduction in their antihypertensive medication regimen.

Carotid Endarterectomy with Autoarterial Remodeling of Bifurcation of the Common Carotid Artery and Carotid Endarterectomy with Patch Closure: Comparison of Methods

BACKGROUND

The objectives of our research were to identify whether the new method of carotid endarterectomy (CEA) with autoarterial remodeling of bifurcation of the common carotid artery (ARBCCA) influences daily parameters of blood pressure and heart rate (HR) while monitoring them on a daily basis and to assess the efficacy of the suggested method.

MATERIALS AND METHODS

It is a prospective randomized comparative study. The first group (n = 100) included patients that underwent ARBCCA, the second group (n = 100) included patients that underwent "classic" CEA with xenopericardial patch closure. Diurnal Holter recording of blood pressure and (HR) was performed before and after the surgical treatment in both groups.

RESULTS

Surgical treatment in both groups leads to an increase of HR, arterial hypertension time index by systolic blood pressure, and arterial hypertension time index by diastolic arterial blood pressure. The damage of carotid artery bulb increases sympathetic innervation and causes dysregulation of the baroreceptor mechanism.

CONCLUSIONS

In our study, we did not reveal a significant difference in the incidence of postoperative hypertension and the dependence of HR on the choice of surgical technique. Thus, the proposed ARBCCA method does not lead to an increased risk of pre-existing arterial hypertension development. A significant difference is found out on the parameter of the clamping time of carotid arteries in favor to ARBCCA group. Another advantage of the suggested technique is the number of restenosis greater than 50% during the 2-year follow-up (4 [4%] cases (ARBCCA group) versus 12 [12%] cases ["classic" CEA], respectively, P = .037).

Prolonged hypotension after carotid artery stenting: incidence, predictors and consequences

BACKGROUND

Hemodynamic changes frequently occur after carotid artery stenting (CAS), and in some patients these changes, particularly hypotension, may be prolonged. There are discrepant results for predicting patients at high risk for these prolonged hemodynamic changes and identifying the effect on clinical outcome. In this study, we aimed to determine the frequency, predictors and consequences associated with prolonged hypotension (PH) after CAS in our center.

METHODS

We retrospectively analyzed the demographics, risk factors, nature of carotid disease, degree of stenosis of both internal carotid arteries, stent diameter and site of dilatation during stenting in 137 CAS procedures. After CAS, duration of hospital stay, complications during hospital stay and major vascular events or death in a 3-month period were evaluated. PH was defined as a systolic blood pressure <90 mmHg lasting more than 1 h despite adequate treatment after CAS.

RESULTS

PH occured in 23 (16.8%) patients. The presence of contralateral stenosis ≥70% and absence of diabetes mellitus were significantly associated with PH. Duration of hospital stay was significantly longer in patients with PH. No patients with PH had a periprocedural complication or major vascular events in the follow-up period.

CONCLUSION

PH was more prevalent in patients with contralateral high-degree carotid stenosis and patients without diabetes mellitus after CAS. PH did not cause any post-procedural complications or major vascular events at follow-up, but it resulted longer hospital stays. Further studies are needed to better define the pathophysiologic mechanisms underlying these hemodynamic alterations.

Complications and Predictors of Hypotension Requiring Vasopressor after Carotid Artery Stenting

A significant controversy exists regarding the clinical impact of hemodynamic depression on major adverse events after carotid artery stenting (CAS). The purpose of this study was to evaluate the incidence, predictors, and clinical significance of hypotension after CAS. A total of 118 cases of carotid artery stenosis were treated with CAS. Hypotension was defined as sustained systolic blood pressure <80 mmHg and requiring intravenous administration of vasopressor to maintain adequate systolic blood pressure after the procedure. Baseline characteristics, procedural characteristics, and periprocedural major adverse events were retrospectively compared between postprocedural hypotension group and non-hypotension group. Morphological and procedural characteristics were not significantly different between the two groups. Periprocedural major adverse events, presence of new ischemic lesions, and number of new ischemic lesions were not significantly different between the two groups (P = 1, P = 0.36, P = 0.68). Hypertension was an independent protective factor (P = 0.037), and use of proximal protection and the distance from carotid bifurcation to maximum stenotic lesion ≤ 10 mm were independent risk factors for developing hypotension after CAS (P = 0.034, P = 0.027). There was no significant relationship between hypotension after CAS and major adverse events in this study. Maintenance of periprocedural adequate cerebral perfusion is thought to be important to prevent ischemic complications due to hypotension after CAS, especially in these cases.

Beneficial effects of prolonged blood pressure control after carotid artery stenting

Objectives

The main purpose of this study was to investigate whether carotid artery stenting (CAS) plus medicine in patients with severe carotid artery stenosis provide a better long-term blood pressure (BP) control compared to other medical treatments alone. The other aim was to explore the correlation between post-CAS hypotension within 6 h and long-term BP reductions after CAS.

Materials and methods

Patients with severe carotid stenosis were recruited either in the CAS group or in the medication group. BPs and the number of classes of antihypertensive agents were recorded at baseline, 6, and 12 months. Extra BP information was collected at 6 h, 3 days, and 1 month after CAS. Univariate and multivariate linear regressions were performed to test the relationship of BP changes among CAS and medication groups after 6 and 12 months of follow-up. Univariate linear regressions were also used to determine the correlations between the mean or maximal systolic BP (SBP) reductions at 6 h and 1 year post-CAS.

Results

In total, 72 members in the CAS group and 82 members in the medication group were recruited. Compared with the medication group, patients in the CAS group had greater BP reductions at 6 and 12 months of follow-up after adjusting for confounding factors (13.56 mmHg at 6 months, P=0.0002; 16.98 mmHg at 12 months, P<0.0001). This study also shows significant positive correlations between the mean or maximal SBP reductions 6 h post-CAS and SBP reductions 1 year post-CAS (β =0.20±0.07, P=0.0067 and β =0.47±0.10, P<0.0001, respectively).

Conclusion

As compared to medical treatment alone, CAS may provide significant beneficial effect on long-term BP control 1 year post-CAS. Furthermore, SBP reductions 6 h post-CAS may predict the SBP reductions 1 year post-CAS.

Prediction of Prolonged Hemodynamic Instability During Carotid Angioplasty and Stenting

Purpose

The aim of this study was to assess the risk factors of prolonged hemodynamic instability (HDI) after carotid angioplasty and stenting (CAS). Herein, a simplified predictive scoring system for prolonged HDI is proposed.

Materials and Methods

Sixty-six patients who had CAS from 2011 to 2016 at a single institution were evaluated. Prolonged HDI was defined as systolic blood pressure >160 mm Hg or <90 mm Hg or heart rate <50 beats/min, lasting over 30 minutes despite medical treatments. For the study, clinical data and radiologic data, including plaque morphology and stenosis were analyzed.

Results

Prolonged HDI was observed in 21 patients (31.8%). Multivariable analysis revealed that calcification (OR, 6.726; p=0.006), eccentric stenosis (OR, 3.645; p=0.047) and extensive plaque distribution (OR, 7.169; p=0.006) were related to prolonged HDI. According to these results, a simplified scoring scale was proposed based on the summation of points: 2 points for calcified plaque, 2 points for extensive plaque distribution, and 1 point for eccentric stenosis. The percentages of prolonged HDI according to the total score were as follows: score 0, 8.7%; score 1, 20.0%; score 2, 38.5%; score 3, 72.7%; score 4, 66.7%; score 5, 100%. From the analysis, the total score in patients with prolonged HDI was significantly higher than those without prolonged HDI (p<0.001).

Conclusion

Prolonged HDI can be associated with calcification of plaque, eccentric stenosis and extensive plaque distribution, and a simplified scoring system enables prediction of prolonged HDI according to our cohort.

Reevaluation of Temporary Transvenous Cardiac Pacemaker Usage During Carotid Angioplasty and Stenting: A Safe and Valuable Adjunct

Although many current series document the safety of carotid angioplasty and stenting procedures (CAS), several acknowledge clinically significant hemodynamic disturbances in 25–71% of patients. We report herein the safety and efficacy of prophylactic percutaneous temporary transvenous cardiac pacemaker insertion during CAS for the prevention of hemodynamic changes. At a community-based institution, 48 patients undergoing 51 attempted CAS procedures from March 1999 to August 2002 for carotid artery occlusive disease were retrospectively reviewed. Thirty-one percent of patients had procedures performed for either recurrent disease or a history of neck radiation; 62.5% had significant coronary disease. Temporary transvenous pacemakers were inserted as an adjunctive procedure in the authors’ CAS protocol. The pacers were set to capture a heart rate decrease below 60 beats per minute. Demographics, cardiac risk, and outcomes were analyzed. CAS was successfully performed in 96% (49 lesions). In the intent-to-treat group, the patients had a mean age of 71 ±9 years and angiographic stenoses of 88 ±8%, with 29% having symptomatic lesions. Significant bradycardia or asystole to trigger ventricular pacing occurred in 11 (22%) procedures, thus, triggering ventricular pacing. Pharmacologic support for concomitant hypotension was temporarily necessary in only 4 (8%) cases. No patient required prolonged pacing or medication therapy following CAS. Neither presence of carotid-related symptoms nor disease etiology was related to need for intraprocedural pacing. Furthermore, there was no occurrence of pacemaker failure or other complication secondary to venous catheterization. Hemodynamic changes may occur during mechanical dilation of the carotid artery and bulb, with reports in the literature of the need for prolonged pharmacologic support. In selected patients, the prophylactic placement of a transvenous pacemaker is a safe, feasible, and expeditious method to treat periprocedural hemodynamic changes with a decrease in additional pharmacologic support during CAS.

Hypotension and Bradycardia after Elective Carotid Stenting: Frequency and Risk Factors

Purpose:

To investigate the frequency of and risk factors for hypotension and bradycardia in response to elective carotid stenting and their association with neurological complications.

Methods:

A retrospective analysis was conducted of 471 patients (321 men; median age 72 years, interquartile range 64–77) who underwent elective carotid artery stenting without cerebral protection for high-grade (>70%) symptomatic (n = 147) or asymptomatic (n=324) internal carotid artery stenosis at a single center. Frequency and potential risk factors for severe hypotension (systolic blood pressure <80 mmHg) or bradycardia (heart rate <50 bpm) were studied.

Results:

Thirty-four (7%) patients had severe hypotension (n=23), bradycardia (n=2), or both (n=9) despite routine premedication with atropine and adequate fluid balance. Intravenous catecholamines (dopamine) were necessary in 8 patients with prolonged hypotension; none of the patients with bradycardia needed pacemaker support. Neurological complications (transient ischemic attack, minor stroke, major stroke, death) occurring in 33 (7%) patients were not significantly associated with hemodynamic instability (4/34 [12%] versus 29/437 [7%], p = 0.26). Age >77 years (fourth quartile; OR 6.40, 95% CI 1.80 to 22.78, p=0.004) and coronary artery disease (OR 2.81, 95% CI 1.29 to 6.14, p=0.010) were associated with an increased adjusted risk for hypotension or bradycardia.

Conclusions:

Hemodynamic instability due to hypotension and bradycardia in response to carotid artery stenting occurs in a relatively low proportion of patients. Elderly patients and those with coronary artery disease are at highest risk. Although the rate of neurological complications was not significantly increased in patients with hemodynamic instability, the higher frequencies of neurological complications in these patients admonish us to be careful.

Short and Long-Term Effect of Carotid Artery Stenting on Arterial Blood Pressure Measured through Ambulatory Blood Pressure Monitoring

BACKGROUND

The aim of this study was to assess the short and long-term effects of carotid artery stenting (CAS) procedure on blood pressure (BP) through ambulatory BP monitoring.

METHODS

One hundred fifty three patients who underwent CAS for primary or secondary protection from December 2010 to September 2013 were enrolled to our study. The BP levels of total of 123 patients were monitored for 1 year. Thereafter, the pre-procedure levels of BP were compared with BP levels at the 24-hour and the first year intervals after the procedure.

RESULTS

Systolic and diastolic BP levels at the 24-hour and the first year intervals after CAS were significantly lower than the pre-procedure BP levels. The mean 24-hour systolic BP was 113 ± 13 mmHg and diastolic BP was 63 ± 8 mmHg, both of which were significantly lower (p < 0.001 and p < 0.001 respectively), while the pre-procedure mean systolic BP was 133 ± 10 mmHg and the mean diastolic BP was 75 ± 9 mmHg. Moreover, the mean first-year systolic BP was 125 ± 10 mmHg with a decline of 8 ± 8 mmHg and mean diastolic BP was 71 ± 8 mmHg with a decline of 4 ± 7 mmHg, both of which were again significantly lower compared to the pre-procedure levels (p < 0.001 and p < 0.001 respectively).

CONCLUSIONS

The results of our study suggested that systolic and diastolic BP levels diminished after CAS. Additionally, BP reduction continued even 1 year after the CAS.

Beta-blocker use is associated with lower stroke and death after carotid artery stenting

BACKGROUND

Proper selection of patients for carotid artery stenting (CAS) remains controversial despite multiple controlled trials. This relates in part to differences in interpretation of the relative importance of myocardial vs stroke complications after the procedure by different specialties and a lack of granular clinical data to analyze outcomes outside the large clinical trials. The objective of this study was to assess the effect of preoperative medications, procedure parameters, and patient characteristics on outcomes of CAS performed in a multispecialty national database.

METHODS

We analyzed all patients who underwent CAS between 2005 and 2014 in the Vascular Quality Initiative. A multivariate logistic regression model was built to assess the effects of age, gender, comorbidities, smoking, preprocedure medications, procedure details, and hypotension or hypertension that required intravenous medication on 30-day death or stroke rates.

RESULTS

A total of 5263 patients underwent CAS (mean age, 70 years; 63% male). The 30-day stroke/death rate was 3.4% (1.5% minor stroke, 0.9% major stroke, and 1.2% death; 40% of patients who had major strokes died within 30 days), and the myocardial infarction rate was 0.8%. Postprocedural hypertension requiring treatment occurred in 519 cases (9.9%), and it was associated with a 3.4-fold increase in stroke/death (odds ratio, 3.39; 95% confidence interval, 2.30-5.00; P < .0001). Preprocedural beta-blocker use for >30 days was associated with a 34% reduction in the stroke/death risk (odds ratio, 0.66; 95% confidence interval, 0.46-0.95; P = .025) compared with nonuse. Beta-blocker use was not associated with postprocedural hypotension. Other predictors of postoperative stroke and death included age, symptomatic status, diabetes (type 1 or type 2), and postprocedural hypotension, whereas prior carotid endarterectomy and distal embolic protection use were protective.

CONCLUSIONS

Postprocedural hypertension and hypotension that require treatment are both strongly associated with periprocedural stroke/death after CAS. Beta blockers significantly reduce the stroke/death risk associated with carotid stenting and should be investigated prospectively for potential use during CAS.

Mechanism of Procedural Stroke Following Carotid Endarterectomy or Carotid Artery Stenting Within the International Carotid Stenting Study (ICSS) Randomised Trial

OBJECTIVE

To decrease the procedural risk of carotid revascularisation it is crucial to understand the mechanisms of procedural stroke. This study analysed the features of procedural strokes associated with carotid artery stenting (CAS) and carotid endarterectomy (CEA) within the International Carotid Stenting Study (ICSS) to identify the underlying pathophysiological mechanism.

MATERIALS AND METHODS

Patients with recently symptomatic carotid stenosis (1,713) were randomly allocated to CAS or CEA. Procedural strokes were classified by type (ischaemic or haemorrhagic), time of onset (intraprocedural or after the procedure), side (ipsilateral or contralateral), severity (disabling or non-disabling), and patency of the treated artery. Only patients in whom the allocated treatment was initiated were included. The most likely pathophysiological mechanism was determined using the following classification system: (1) carotid-embolic, (2) haemodynamic, (3) thrombosis or occlusion of the revascularised carotid artery, (4) hyperperfusion, (5) cardio-embolic, (6) multiple, and (7) undetermined.

RESULTS

Procedural stroke occurred within 30 days of revascularisation in 85 patients (CAS 58 out of 791 and CEA 27 out of 819). Strokes were predominately ischaemic (77; 56 CAS and 21 CEA), after the procedure (57; 37 CAS and 20 CEA), ipsilateral to the treated artery (77; 52 CAS and 25 CEA), and non-disabling (47; 36 CAS and 11 CEA). Mechanisms of stroke were carotid-embolic (14; 10 CAS and 4 CEA), haemodynamic (20; 15 CAS and 5 CEA), thrombosis or occlusion of the carotid artery (15; 11 CAS and 4 CEA), hyperperfusion (9; 3 CAS and 6 CEA), cardio-embolic (5; 2 CAS and 3 CEA) and multiple causes (3; 3 CAS). In 19 patients (14 CAS and 5 CEA) the cause of stroke remained undetermined.

CONCLUSION

Although the mechanism of procedural stroke in both CAS and CEA is diverse, haemodynamic disturbance is an important mechanism. Careful attention to blood pressure control could lower the incidence of procedural stroke.

Effects of Carotid Stenting on Nocturnal Nondipping Phenomenon

BACKGROUND

It is well known that nondipper blood pressure (BP) pattern is associated with an increased cardiovascular risk in hypertensive patients. The aim of this study is to observe whether carotid artery stent (CAS) procedure returns nondipper BP pattern to dipper pattern in hypertensive patients.

METHODS

Ambulatory BP monitorization (ABPM) was performed in 152 hypertensive patients who underwent CAS procedure 1 day before, and 1 day and 1 year after the procedure. BP monitorization of patients was classified as dipper and nondipper. BP parameters 1 year after CAS procedure were compared with preprocedure parameters.

RESULTS

According to baseline ambulatory BP follow-ups, a total of 152 hypertensive patients with 122 (80%) nondippers and 30 (20%) dippers were enrolled in this study. According to ABPM results 1 year after CAS procedure, 78 patients (64%) who had nondipper pattern at first transformed into dipper pattern and 44 patients (36%) remained to be nondippers. Moreover, 1 year after CAS procedure, 18 patients (60%) who had dipper pattern at first transformed into nondipper pattern and 12 patients (40%) remained as dippers. When BP follow-up values at 1 year after CAS procedure were compared with BP readings before the procedure, 78 patients (51%) who were nondipper before the procedure transformed into dipper pattern (P ≤ .01), whereas 44 patients (29%) with nondipper pattern remained to be nondippers (P = .01). Twelve patients (7.9%) who had dipper pattern remained to have dipper pattern (P = .768). Eighteen patients who had dipper pattern (12%) transformed into nondipper pattern after the procedure (P < .01). The total number of nondipper pattern patients before CAS procedure was 80.3% (122 patients), whereas this percentage dropped to 40.8% (62 patients) after the CAS procedure (P < .01).

CONCLUSIONS

During 1-year follow-up after CAS procedure, nondipper BP pattern transforms into dipper pattern. This result might be attributed to the contributory effect of CAS procedure to long-term cardiovascular protection.

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.

Dysautonomic responses during percutaneous carotid intervention: principles of physiology and management

Percutaneous carotid artery stenting (CAS) has emerged as a less invasive alternative to carotid endarterectomy for the treatment of carotid atherosclerotic disease. The main risk of CAS is the occurrence of neuro-vascular complications; however, carotid artery stenting-related dysautonomia (CAS-D) (hypertension, hypotension, and bradycardia) is the most frequently reported problem occurring in the periprocedural period. Alterations in autonomic homeostasis result from baroreceptor stimulation, which occurs particularly at the time of balloon inflation in the region of the carotid sinus. The response can be profound enough to induce asystole or even complete cessation of postganglionic sympathetic nerve activity. Frequency and factors predisposing a patient to CAS-D have been investigated in several studies; however, there are significant discrepancies in results among reports. Lack of consistent findings may arise from using different methods and definitions, as well as other factors discussed in detail in this review. Furthermore, a correlation of CAS-D with short and long-term outcomes has been investigated only in small and mostly retrospective studies, explaining why its prognostic significance remains uncertain. In this manuscript, we have focused on risk factors, pathophysiology and management of periprocedural autonomic dysfunction. As there is no standardized approach to the treatment of CAS-D, we present an algorithm for the periprocedural management of patients undergoing CAS. The proposed algorithm was developed based on our procedural experience as well as data from the available literature. The Yale Algorithm was successfully implemented at our institution and we are currently collecting data for short- and long-term safety. © 2014 Wiley Periodicals, Inc.

Incidence and timing of hypotension after transcervical carotid artery stenting: correlation with postoperative complications

OBJECTIVES

To assess the incidence and timing of hypotension after carotid artery stenting (CAS) and its correlation with postoperative complications.

BACKGROUND

CAS-associated postoperative hypotension has been linked to surgical morbidity and mortality, especially to stroke and cardiac complications.

METHODS

Ninety-seven consecutive patients undergoing transcervical CAS were monitored for at least 12 hr after operation. Hypotension was defined as systolic blood pressure < 90 mm Hg. Patients were divided into three groups: normal blood pressure and early (≤6 hr) and late (>6 hr) hypotension. Complications were recorded.

RESULTS

Hypotension occurred in 34% of the patients (early hypotension in 63% of them). Hypotension was recorded in 21.6% of patients during surgery and in 21.6%, 15.5%, and 1.0% at 6, 12, and 24 hr postoperatively. Bradycardia occurred in 26.8% during operation and in 25.8%, 13.4%, and 10.3% at 6, 12, and 24 hr after surgery. Intraoperative bradycardia (P = 0.01) and hypotension (P = 0.02) were predictors of postoperative hypotension. The overall rate of complications was 5% without differences between the study groups. The mean length of stay was 3, 3.6, and 2.8 days in the normotensive, early hypotension, and late hypotension groups, respectively.

CONCLUSIONS

Most postoperative hypotension episodes occurred within the first 6 hr, and more than one-third between the 6 and 12 hr post-procedure. All patients with late hypotension were asymptomatic. There was no difference in complications between the study groups. In patients undergoing ambulatory CAS, hemodynamic monitoring in the postoperative period is particularly important during the first 12 hr.