Cost-effectiveness of Intraoperative Imaging in Carotid Endarterectomy

Impact of Routine Intracerebral Completion Angiography on Outcomes After TransCarotid Artery Revascularization

OBJECTIVES

Completion intracerebral angiography (CIA) following transcarotid artery revascularization (TCAR) aims to identify distal embolization after stenting and serve as a measure of intraoperative quality control. Nevertheless, there is no general evidence regarding the benefit of performing routine CIA. The aim of this study was to evaluate the potential risk and benefit of routine CIA.

METHODS

We retrospectively reviewed the Vascular Quality Initiative (VQI) database for transcarotid artery revascularization between 2016-2021. Patients were divided into two groups: patients with no CIA performed and those with completion angiography performed. The primary outcome was in-hospital stroke or death. Secondary outcomes included stroke, death, myocardial infarction (MI) and return to the operating room (RTOR). Clinically relevant and statistically significantly variables on univariable analysis were added to a logistic regression model clustered by center identifier.

RESULTS

A total of 18,155 patients who underwent TCAR were identified, 63.7% of them had routine CIA performed. Patients who had routine CIA were more likely to have contralateral carotid occlusion and general anesthesia. After adjusting for potential confounders, we found no difference in the risk of stroke or death (aOR): 1.03, 95%CI (0.8-1.3), P=.820), stroke/TIA (aOR, 1, 95%CI (0.8-1.3), P=.998), stroke (aOR: 1.1, 95%CI (0.8-1.4), P=.452), death (aOR: 0.98, 95%CI (0.6-1.6), P=.953), MI (aOR: 0.78, 95%CI (0.5-1.2), P=.240), or RTOR (aOR: 1.5, 95%CI (0.6-3.8), P=.412) between patients who had CIA compared to those who did not. A sub-analysis of patients who had new occlusion detected on CIA (69 patients, 0.6%; 19 not treated and 50 treated) indicated higher risk of stroke or death in patients with treated new occlusions (OR: 7.1, 95%CI (2.9-17.3), P<.001) and stroke/TIA (aOR, 5.8, 95%CI (2.3-14.7), P<.001) compared to patients who had no CIA. However, no difference in stroke/death (OR: 3.3, 95%CI (0.37-29.5), P=.283) or stroke/TIA (aOR, 3.1, 95%CI (0.3-29.4), P=.327) was found in patients with non-treated new occlusions compared to patients who had no CIA.

CONCLUSIONS

In this retrospective study, routine performance of completion cerebral angiography was not beneficial with no significant differences in in-hospital stroke or death detected. Detection of new lesions on completion cerebral angiography was rare. Moreover, identifying new occlusions following intracranial angiography was associated with higher odds of stroke or death when these new lesions are treated. Further studies are needed to define the etiology of worse outcomes in patients undergoing intervention for lesions discovered on completion cerebral angiogram and delineate optimal timing for further imaging and intervention.

Practice patterns in the use of completion imaging after carotid endarterectomy

BACKGROUND

The use of intraoperative completion imaging (completion carotid duplex ultrasound or angiography) to confirm the technical adequacy of carotid endarterectomy (CEA) remains a matter of controversy. The purpose of this study was to describe vascular surgeons' practice patterns in the use of completion imaging after CEA and to study the association between completion imaging and postoperative stroke/death and high-grade restenosis (>70%).

METHODS

Patients who underwent CEA without concomitant procedures in the Vascular Quality Initiative database between 2003 and 2018 were included. Surgeons' practice patterns were defined on the basis of the distribution of completion imaging use among annual CEA cases per surgeon. Multivariable and Cox proportional hazards models were used to study the association between different practice patterns of completion imaging and perioperative and 1-year outcomes after CEA.

RESULTS

Of 98,055 CEA cases, 26,716 (27.3%) were performed with completion imaging. Compared with cases in which completion imaging was not performed, completion imaging was associated with increased rates of immediate re-exploration (3.5% vs 0.9%; odds ratio [OR], 3.84; 95% confidence interval [CI], 2.74-5.38; P < .001), overall return to the operating room (RTOR; 1.6% vs 1.2%; OR, 1.24; 95% CI, 1.08-1.42; P < .01), and longer operative time (median [interquartile range], 105 minutes [82-132] vs 119 minutes [92-148]; P < .001). Of 1920 surgeons in our cohort, 45% never performed completion imaging, whereas 26% rarely performed completion imaging (for ≤20% of annual CEA cases), 9.5% performed it selectively (21%-79% of annual CEAs), and 19.6% used completion imaging routinely (≥80% of annual CEAs). Rarely performing completion imaging had higher rates of immediate re-exploration (6.5% vs 0.9%; OR, 7.2; 95% CI, 5.7-9.2; P < .001), in-hospital stroke (4.0% vs 1.1%; adjusted OR [aOR], 3.4; 95% CI, 2.6-4.6; P < .001), RTOR for bleeding (1.9% vs 0.9%; aOR, 2.1; 95% CI, 1.5-2.9; P < .001), and neurologic events (1.5% vs 0.4%; aOR, 3.6; 95% CI, 2.2-5.9; P < .001) compared with not performing completion imaging. It was also associated with increased stroke/death and repeated revascularization at 30 days and significant restenosis at 1 year. On the other hand, performance of selective and routine completion imaging was associated with increased immediate re-exploration (selective: aOR, 3.2 [95% CI, 1.9-5.5; P < .001]; routine: aOR, 3.7 [95% CI, 2.5-5.6; P < .001]) without any increase in in-hospital, 30-day, and 1-year adverse outcomes compared with cases performed without completion imaging.

CONCLUSIONS

The performance of selective or routine completion imaging during CEA is safe and is not associated with increased adverse events compared with not using intraoperative completion imaging. However, rarely performing completion imaging is associated with a significant increase in the odds of perioperative stroke/death and RTOR, possibly because of unnecessary re-exploration for minor defects. The operator's experience and establishing a criterion for fixing residual defects are important to avoid unnecessary re-exploration.

Extracranial carotid stenosis: evidence based review

Extracranial cerebrovascular disease is one of the most important causes of death and disability worldwide and its treatment is based on clinical and surgical strategies, the latter being performed by conventional or endovascular techniques. The management of stenosis of the carotid bifurcation is mainly aimed at preventing stroke and has been the subject of extensive investigation. The role of clinical treatment has been re-emphasized, but carotid endarterectomy remains the first-line treatment for symptomatic patients with 50% to 99% stenosis and for asymptomatic patients with 60% to 99% stenosis. Stent angioplasty is reserved for symptomatic patients with stenosis of 50% to 99% and at high risk for open surgery due to anatomical or clinical reasons. Currently, the endovascular procedure is not recommended for asymptomatic patients who are able to undergo conventional surgical treatment. Brazil presents a trend similar to that of other countries in North America and Europe, keeping endarterectomy as the main indication for the treatment of carotid stenosis and reserving the endovascular procedure for cases in which there are contraindications for the first intervention. However, we must improve our results by reducing complications, notably the overall mortality rate.

Intraoperative sonography during carotid endarterectomy: normal appearance and spectrum of complications

Carotid endarterectomy is a commonly performed procedure for prevention of stroke related to carotid stenosis. Intraoperative sonography is used to identify potentially correctable technical defects during carotid endarterectomy. The main risk of endarterectomy is perioperative stroke, and great effort has been put into trying to reduce this risk through various surgical techniques and evaluation of the surgical bed. Postoperative carotid thrombosis, or thombo-embolization from the arterectomy site, remains a common cause of perioperative stroke and is often related to technical defects in the arterial reconstruction procedure. Re-exploration and repair of any imperfections have the potential to improve outcomes. Intraoperative imaging can identify potentially occult lesions, provide the option for correction, and thus reduce chance of stroke. Familiarity with the spectrum of intraoperative sonographic findings helps correctly identify residual intimal dissection flaps, plaque, thrombi, and stenosis, which may require immediate surgical revision. Our objective is to illustrate the spectrum of intraoperative findings and their importance.

Use of intraoperative duplex ultrasonography for identification and patch repair of kinking stenosis after carotid endarterectomy: a single-surgeon retrospective experience

OBJECTIVE

To provide an incidence and descriptive evaluation of kinking of the internal carotid artery (ICA) after carotid endarterectomy (CEA) in a consecutive CEA series that included the use of intraoperative duplex ultrasonography (IDUS) monitoring and to determine the effect of kink patch repair on long-term postoperative ICA restenosis.

METHODS

The electronic medical records and IDUS recordings of all CEA cases performed over a 10-year period (March 2000 to October 2010) by a single neurosurgeon were retrospectively reviewed to assess cases of kinking after CEA.

RESULTS

IDUS assisted in the identification of 27 of 285 cases (9.5%) of kinking after CEA. Kinked vessels with hemodynamically significant peak systolic velocities of ≥ 120 cm/second on IDUS (11 of 285 cases; 3.9%) were repaired using a synthetic patch. During follow-up, there were no neurologic symptoms, stroke, or death related to a cerebrovascular accident associated with kinking. The total incidence of postoperative stroke in this CEA series was 3 of 285 cases (1.1%).

CONCLUSIONS

ICA kinking stenosis after CEA was a common finding in this CEA series. Because of their unique anatomic and hemodynamic properties, the identification and assessment of kinks after CEA required the use of IDUS monitoring. A selective patch closure method for kinked vessels with peak systolic velocities of ≥ 120 cm/second identified by IDUS was effective in resolving hemodynamically significant stenosis and minimizing long-term postoperative restenosis.

Limited economic evidence of carotid artery stenosis diagnosis and treatment: a systematic review

The objective of this article is to assess the availability and validity of economic evaluations of carotid artery stenosis (CS) diagnosis and treatment.

DESIGN

Systematic review of economic evaluations of the diagnosis and treatment of CS.

METHODS

Systematic review of full economic evaluations published in Medline and Google Scholar up until 28 February 2012. Based on economic checklists (Evers and Philips), the identified studies were classified as high, medium, or low quality.

RESULTS

Twenty-three evaluations were identified. The study quality ranged from 26% to 84% of all achievable points (Evers). Seven studies were of high, eight of medium and eight of low quality. No comparison was made between carotid angioplasty and stenting (CAS) and best medical treatment (BMT). For subjects with severe stenosis, comparisons of carotid endarterectomy (CEA) and BMT were also missing. Three of five studies dealing with pre-operative imaging found that duplex Doppler ultrasound (US) was cost-effective compared with carotid angiogram (AG).

CONCLUSIONS

There is a huge lack of high-quality studies and of studies that confirm published results. Also, for a given study quality, the most cost-effective treatment strategy is still unknown in some cases ('CAS' vs. 'BMT', 'US combined with magnetic resonance angiography supplemented with AG' vs. 'US combined with computer tomography angiography').

Early acute hemispheric stroke after carotid endarterectomy. Pathogenesis and management

PURPOSE

A major stroke after carotid endareterectomy (CEA) is an event that should be managed according to a planned strategy. Literature data on this issue are not definitive. We reviewed our series in the attempt to define an algorithm of treatment if this complication occurs.

METHODS

A consecutive series of 413 CEAs in 390 patients was considered. All operations were performed under general anaesthesia and EEG monitoring. An indwelling shunt was inserted only according to EEG changes. Direct closure of the arteriotomy was performed in all cases. Intraoperative ultrasound was not routinely employed before 2004. Patients who suffered from the new onset of an ischaemic hemispheric deficit or the worsening of a pre-existing deficit within 72 h after surgery were included in the present study.

RESULTS

Sixteen patients (3.9%) suffered from perioperative stroke. Seven patients presented neurological deficits that rapidly and spontaneously resolved. In nine cases (2.2%) a major stroke occurred. Acute occlusion of the internal carotid artery (ICA), with or without embolic blocking of the omolateral M1 segment, occurred in eight cases; in one case a patent ICA was associated with the occlusion of two frontal branches of the omolateral middle cerebral artery. Seven cases were reoperated on. The ICA was reopened in all these cases except one. Among these seven cases, three (42%) had a good outcome.

CONCLUSIONS

A major stroke after CEA is caused, in most of cases, by the acute ICA occlusion with or without intracerebral embolic occlusion. Reopening of the occluded ICA gives good results when intracerebral vessels are patent and when the occluded ICA is satisfactorily reopened. An algorithm of planned reactions in case of perioperative stroke is finally proposed.

Accuracy and Cost Comparison of Ultrasound Versus Alternative Imaging Modalities, Including CT, MR, PET, and Angiography

Ultrasound (US) has become widely used in clinical medicine for the diagnosis of a variety of disease processes. The unique ability of US to provide accurate information through an efficacious, painless, portable, and nonionizing method has expanded its role and application in diverse medical settings. Given the current economic environment and the related interest in creating the greatest value for health care expenditures, US has been evaluated to compare its clinical accuracy/efficacy and cost-effectiveness versus other imaging modalities. The following literature review reports the results of research studies aimed at comparing the accuracy/efficacy and cost of US versus alternative imaging modalities, including magnetic resonance imaging, computed tomography, contrast angiography, and single-photon emission computed tomography.

Bow hunter's syndrome caused by accessory cervical ossification: posterolateral decompression and the use of intraoperative Doppler ultrasonography

BACKGROUND

Bow hunter's syndrome refers to symptomatic vertebrobasilar insufficiency provoked by physiologic head rotation.

CASE DESCRIPTION

We report a unique case of bow hunter's syndrome caused by an accessory cervical ossification and the first use of intraoperative Doppler ultrasonography directly upon the vertebral artery during the surgical repair. After a traumatic motor-vehicle collision, the patient developed recurrent syncopal episodes when he turned his head abruptly to the right. Transcranial Doppler studies and vertebral angiography with the patient's neck rotated into the symptomatic position revealed marked reduction of vertebral artery flow, and fine-cut CT of the upper cervical spine demonstrated the compressive accessory ossicle. Intraoperative Doppler ultrasound performed with the head in neutral and rotated positions, before and after surgical decompression, demonstrated restoration of blood flow in the vertebral artery. We discuss the mechanisms of bow hunter's syndrome and the advantages of intraoperative Doppler ultrasonography.

CONCLUSION

This case describes the first use of intraoperative Doppler ultrasonography directly upon the vertebral artery to provide an unrestricted real-time assessment of the surgical decompression for bow hunter's syndrome.