Results of carotid endarterectomy with the use of temporary shunts with reduced retrograde pressure in the internal carotid artery - analysis of the multicenter Russian register

Aim

The aim of the study was to assess the role of a temporary carotid shunt in patients undergoing carotid endarterectomy.

Materials and methods

This was a retrospective, multicentric (n = 159) study carried out between January 2005 and October 2020. The study included 3114 patients undergoing carotid endarterectomy who had a reduced retrograde internal carotid artery pressure (<60% of systolic blood pressure). A temporary carotid shunt was used in 1328 patients and 1786 patients underwent carotid endarterectomy without a shunt.

Results

The in-hospital outcomes were comparable in terms of the incidence of deaths, myocardial infarctions, and stroke between the two groups. However, asymptomatic strokes (confirmed on computed tomography) occurred more frequently in the group where the temporary shunt was used (34 (2.5%) vs. 10 (0.55%), p < 0.0001). The composite endpoints of adverse events were also higher in the group where a temporary shunt was used (44 (3.3%) vs. 28 (1.5%), p = 0.002). The risk of symptomatic stroke (both fatal and non-fatal) was higher in the group where a temporary shunt was not used, though this was statistically not significant. Logistic regression analysis identified diabetes mellitus and stenosis (81-90%) of the contralateral internal carotid artery to be important predictors for stroke.

Conclusion

Temporary carotid shunts during carotid endarterectomy were associated with increased rates of asymptomatic stroke. There were no statistically significant differences in the incidence of non-fatal or fatal stroke, myocardial infarction, and mortality.

Update in Carotid Disease

This review of the literature analyzes publications over the past five years on various problems associated with carotid endarterectomy: 1. Is the eversion or classical technique of surgery with plastic repair of the reconstruction area with a patch more effective? 2. Carotid endarterectomy or carotid angioplasty with stenting is more optimal? 3. When should brain revascularization be performed after the development of ischemic stroke? 4. Should a temporary shunt be used to protect the brain during carotid endarterectomy? 5. How to prevent and treat different types of intraoperative ischemic strokes? 6. What tactics of treatment of patients with combined lesions of the carotid and coronary arteries is more effective? 7. What are the causes and methods of elimination of restenosis of the internal carotid artery known? 8. Is carotid endarterectomy safe in old age?

Early outcomes of routine delayed shunting in carotid endarterectomy for symptomatic patients

BACKGROUND

The role of shunting during carotid endarterectomy (CEA) in symptomatic patients is unclear. The aim was to evaluate early outcomes of CEA with routine "delayed" shunt insertion, for patients with symptomatic carotid stenosis.

METHODS

we conducted a single-center retrospective review of symptomatic patients undergoing CEA (2009-2020). All CEAs were performed under general anesthesia using a standardized technique, based on delayed routine shunt insertion after plaque removal. Primary endpoints were 30-days mortality and stroke. A logistic regression was performed to identify clinical and procedural factors predictors of post-operative stroke. A literature systematic review was conducted using the terms "carotid endarterectomy" "stroke", "transient ischemic attack", "symptomatic carotid stenosis", and "shunt".

RESULTS

two-hundred-sixty-three CEAs were performed for TIA (n=178, 47%) or acute ischemic stroke (n=85, 32%). Mean delay of surgery was 6±19 days, and early CEA (<48 hours) was performed in 98 cases (37%). Conventional CEA was performed in 171 patients (67%), eversion CEA in 83 (33%). Early (30-days) mortality was 0.3%. Stroke/death rate was 2.3%. Female sex (OR 5.14, 95%CI 1.32-24.93; P=.023), use of anticoagulants (OR 10.57, 95%CI 2.67-51.86; P=.001), preoperative stroke (OR 5.34, 95%CI 1.62-69.21; P=.006), and the presence of preoperative CT/MRI cerebral ischemic lesions (OR 5.96, 95%CI 1.52-28.59; P=.013) were associated with early neurological complications. Statin medication (OR 0.18, 95%CI 0.04-0.71; P=.019) and CEA timing <2 days (OR 0.14, 95%CI 0.03-0.55; P=.005) were protective from postoperative stroke. CEA outcomes were independent from time period (P=.201) and operator's volume (P=.768). Four studies described the CEA outcomes with routine shunting in symptomatic patients, with a large variability in the selection of patients, surgical technique, and description of the results.

CONCLUSIONS

Routine delayed shunting after plaque removal seems to be a safe and effective technique, that contributed to maintain a low complication rate in neurologically symptomatic patients. Statin use and expedited timing were associated with improved outcomes using this technique.

Red blood cell distribution width is associated with hypoperfusion in carotid endarterectomy under regional anesthesia

BACKGROUND

A subset of patients submitted to carotid endarterectomy under regional anesthesia develop intraoperative neurologic deficit during carotid artery crossclamping related to critical cerebral perfusion, which may be owing to low flow or embolic phenomena. This subgroup is deemed prone to worse outcomes, which highlights its clinical relevance. The main aim of this study was to identify clinical and hematological predictors for intraoperative neurologic deficit. The secondary aim was to evaluate the perioperative prognostic value of postcarotid artery crossclamping manifestations of cerebral ischemia.

METHODS

Between January 2012 to January 2020, patients submitted to carotid endarterectomy under regional anesthesia in a tertiary referral center who presented intraoperative neurologic deficit were prospectively and consecutively included. This group constituted 8% of the total carotid endarterectomy performed in the center during this timeframe. The control group of patients was the subsequent patient submitted to carotid endarterectomy without intraoperative neurologic deficit in a 1:1 ratio. Blood samples were collected before surgery (<2 weeks). Propensity score matching was used to identify well-matched pairs of patients.

RESULTS

A total of 180 patients were included, with 90 (50% of the cohort and 8% of total carotid endarterectomies) presenting intraoperative neurologic deficit associated to clamping. Mean age was 71.4 ± 9.27 years in the study group and 68.8 ± 8.36 years in the control group. The clinical variables presenting significance after multivariate analysis include: age (adjusted odds ratio: 1.04, 5-95% confidence interval, [1.003-1.078]; P = .034), obesity (adjusted odds ratio: 3.537 [1.445-8.658]; P = .006), lower ipsilateral carotid stenosis grade (adjusted odds ratio: 0.725 [0.525-0.997]; P = .049), and higher contralateral carotid stenosis grade (adjusted odds ratio: 1.266 [1.057-1.516]; P = .010). Red cell distribution width coefficient of variation demonstrated statistical significance in predicting intraoperative neurologic deficit with an adjusted odds ratio of 1.394 (1.076-1.805); P = .012. The 30-day stroke rate was significantly higher in the intraoperative neurologic deficit group, with an adjusted odds ratio of 5.13 (5-95% confidence interval [1.058-24.87]; P = .042) after propensity score matching. Postoperative complications (Clavien-Dindo ≥2) were also associated with intraoperative neurologic deficit (after propensity score matching adjusted odds ratio of 2.748 [5-95% confidence interval, 0.976-7.741]; P = .051).

CONCLUSION

In this study, increased red cell distribution width coefficient of variation demonstrated value to predict intraoperative neurologic deficit. Additionally, age, obesity, a lower degree of ipsilateral carotid stenosis, and a higher degree of contralateral carotid stenosis also demonstrated ability to predict intraoperative neurologic deficit. Moreover, intraoperative neurologic deficit was an independent risk factor for 30-day stroke and postoperative complications Clavien-Dindo ≥2.

Surgical Pitfalls in Carotid Endarterectomy: A New Step-By-Step Approach

Carotid endarterectomy (CEA) is a surgical intervention that may prevent stroke in asymptomatic and symptomatic patients. Our aim was to examine the microsurgical anatomy of carotid artery and other related neurovascular structures to summarize the CEA that is currently applied in ideal conditions. The upper necks of 2 adult cadavers (4 sides) were dissected using ×3 to ×40 magnification. The common carotid artery, external carotid artery (ECA), and internal carotid artery were exposed and examined. The surgical steps of CEA were described using 3-D cadaveric photos and computed tomography angiographic pictures obtained with help of OsiriX imaging software program. Segregating certain neurovascular and muscular structures in the course of CEA significantly increased the exposure. The division of facial vein allowed for internal jugular vein to be mobilized more laterally and dividing the posterior belly of digastric muscle resulted in an additional dorsal exposure of almost 2 cm. Isolating the ansa cervicalis that pulls hypoglossal nerve inferiorly allowed hypoglossal nerve to be released safely medially. The locations of the ECA branches alter depending on their anatomical variations. The hypoglossal nerve, glossopharyngeal nerve, and accessory nerve pierce the fascia of the upper part of the carotid sheath and they are vulnerable to injury because of their distinct courses along the surgical route. Surgical exposure in CEA requires meticulous dissection and detailed knowledge of microsurgical anatomy of the neck region to avoid neurovascular injuries and to determine the necessary surgical maneuvers in cases with neurovascular variations.