Stenting versus Endarterectomy for Treatment of Carotid-Artery Stenosis

Perioperative Outcomes in Transcarotid Artery Revascularization Versus Carotid Endarterectomy or Stenting Nationwide

BACKGROUND AND OBJECTIVES

Transcarotid artery revascularization (TCAR) is a newer treatment for carotid stenosis where the carotid artery is accessed directly in the neck for stenting. It is less invasive than carotid endarterectomy (CEA) and has less embolic potential than carotid artery stenting (CAS), but population-level utilization of TCAR and outcomes are currently unknown. Our study compares outcomes of TCAR with those of CEA and CAS.

METHODS

The National Inpatient Database was used for years 2015 to 2019. A multivariate logistic regression model was used to compare CEA, CAS, and TCAR outcomes with age, sex, race, hospital teaching status, symptomatic carotid disease status, side of procedure, intraoperative monitoring, and the weighted Elixhauser comorbidity score as covariates.

RESULTS

TCAR comprised 0.69% of these procedures in 2016, rising to 1.35% in 2019. The inpatient rates of death, stroke, and myocardial infarction for TCAR were 0.63% (95% confidence interval: 0.36%, 1.06%), 0.42% (0.21%, 0.80%), and 1.46% (1.04%, 2.05%), respectively. Compared with CEA, TCAR had statistically insignificant difference odds of death, odds ratio (95% CI) for stroke was 0.47 (0.25, 0.87), and for myocardial infarction, it was 0.66 (0.37, 0.94). Compared with CAS, for TCAR, the odds ratio for death was 0.41 (0.24, 0.71), and for stroke, it was 0.48 (0.26, 0.91).

CONCLUSION

TCAR is underutilized relative to other revascularization techniques yet has favorable outcomes compared with CEA and CAS. TCAR may be preferred to CAS in patients not surgical candidates for CEA and has a less invasive possibility for those eligible for CEA.

Stratification of risk of atherosclerotic plaque using Hu’s moment invariants of segmented ultrasonic images

Myocardial infarction is one of the major life-threatening diseases. The cause is atherosclerosis i.e. the occlusion of the coronary artery by deposition of plaque on its walls. The severity of plaque deposition in the artery depends on the characteristics of the plaque. Hence, the classification of the type of plaque is crucial for assessing the risk of atherosclerosis and predicting the chances of myocardial infarction. This paper proposes prediction of atherosclerotic risk by non-invasive ultrasound image segmentation and textural feature extraction. The intima-media complex is segmented using a snakes-based segmentation algorithm on the arterial wall in the ultrasound images. Then, the plaque is extracted from the segmented intima-media complex. The features of the plaque are obtained by computing Hu’s moment invariants. Visual pattern recognition independent of position, size, orientation and parallel projection could be done using these moment invariants. For the classification of the features of the plaque, an SVM classifier is used. The performance shows improvement in accuracy using lesser number of features than previous works. The reduction in feature size is achieved by incorporating segmentation in the pre-processing stage. Tenfold cross-validation protocol is used for training and testing the classifier. An accuracy of 97.9% is obtained with only two features. This proposed technique could work as an adjunct tool in quick decision-making for cardiologists and radiologists. The segmentation step introduced in the preprocessing stage improved the feature extraction technique. An improvement in performance is achieved with much less number of features.

Surgical therapy for chronic internal carotid artery occlusion: a systematic review and meta-analysis

Chronic internal carotid artery occlusion (CICAO) significantly increases the risk of recurrent stroke. Given unfavorable outcomes, revascularization procedures are not generally recommended for CICAO. In the last several years, loads of studies reported successful surgical revascularization for CICAO with promising success rate and favorable short-term outcomes. Meanwhile, due to the lack of high-quality evidence, the safety and efficacy of revascularization procedures remain debatable. This systematic review aims to scrutinize current evidence for the applicability of revascularization for CICAO. We also investigated potential predictors of postoperative prognosis. We searched clinical studies on surgical treatment of CICAO on the Medline, Cochrane library, and Embase databases, published from Jan 1990 to Jan 2021. Surgical operation was restricted to bypass surgery, endarterectomy, endovascular therapy, and hybrid surgery. Controlled clinical studies were included for clinical outcomes. Large-sample single-arm studies were supplemented to assess complications and success rate. Co-primary endpoints were technical success rate and neurological function; secondary endpoints were recurrent stroke/cerebrovascular events, complications, and deaths within follow-up. This systematic review has been registered in PROSPERO (CRD42020181250). One RCT and 5 cohort studies with a total of 465 patients were included in this review. Seven single-arm studies were supplemented for assessing success rate and complications. Bypass surgery presented the highest graft patency of 96% and a low incidence of complications, but no benefits on neurological function, recurrent stroke, or deaths. Endovascular therapy (carotid stenting) was characterized by a relatively lower technical success rate, significant neurological function recovery, and nonsignificant reduction of cerebrovascular events and deaths. Hybrid surgery was considered as a potential treatment for CICAO because of a high technical success rate and significant neurological improvement. Endarterectomy is only suitable for short-segment occlusion. Prospective clinical trials should focus on carotid stenting and hybrid surgery for their significant capacity of improving neurologic function and potential capacity of reducing deaths and cerebrovascular events.

A clinical study on the effect of open chronic total occlusion on hemodynamics of collateral circulation donor

OBJECTIVE

This study applied pressure measurement to measure the hemodynamic changes in right coronary artery (RCA) donor vessels before and after the opening of the vessel in patients with left anterior descending chronic total occlusion (LAD-CTO) interventional therapy.

METHODS

A total of 45 patients with LAD-CTO were divided into two groups of percutaneous coronary intervention (PCI) to observe the hemodynamic changes (fractional flow reserve [FFR] and instantaneous wave-free ratio [iFR]) before and after opening the chronic total occlusion (CTO), in order to provide collateral circulating donor vessels to the CTO, and observe the changes in iFR and FFR. The results of these two measures were compared to determine the significance of the donor vascular function.

RESULTS

A total of 45 patients with LAD-CTO successfully underwent LAD-CTO interventional therapy, and were immediately measured for FFR and iFR of the donor vessels. The FFR changes before right coronary artery flow reserve (RCAFR) was 0.73±0.083, and after the operation, this was 0.77±0.073. The iFR changes before RCAFR was 0.90±0.048, and after the operation, this was 0.93±0.034. Before and after the opening of the RCA, the FFR change (ΔFFR) and iFR change (ΔiFR) were also correlated with r = 0.033 (0.041-0.568: P < 0.05). A total of 19 cases had a FFR value of <0.75 before the operation, and the average FFR before and after the PCI was 0.65±0.048 and 0.72±0.057, respectively. Furthermore, the ΔFFR was 0.076±0.057 (n = 19), and FFR was >0.75 in 26 cases. The ΔFFR was 0.017±0.0088 (n = 26). These two groups were compared, P = 0.0032 (P < 0.05).

CONCLUSION

The FFR and iFR results were the same in terms of RCA hemodynamic changes, after the LAD-CTO was opened. For the RCA with a preoperative FFR of <0.75, the increase in RCAFR after LAD-CTO PCI was more obvious.

Mastering transcarotid artery revascularization (TCAR) instrumentation efficiency

Transcarotid artery revascularization is a relatively new minimally invasive procedure used to treat patients with carotid atherosclerosis deemed high risk for open revascularization and is reported to have lowest stroke rate of any carotid intervention. The novel applicability of this technique creates new and additional considerations with regard to efficiency in the operating theater, most notably instrumentation and turnaround. This article discusses our unique challenges and the subsequent improvements implemented to optimize and maintain our operating room efficiency and case volume throughput while ultimately reducing costs and resource wastage.

[Changes in cerebral perfusion in patients undergoing revascularization of carotid artery stenosis]

Ischemic stroke is caused by atherosclerotic lesions in extra- and intracranial arteries in about 25% of cases. Revascularization surgery has been long and widely used for secondary prevention of ischemic stroke in patients with atherosclerotic lesions of the carotid arteries. However, currently the changes in cerebral perfusion in patients with atherosclerotic lesions of brachiocephalic arteries, who underwent surgical revascularization, are still not fully understood. This article highlights the issues of changes of cerebral hemodynamics in patients undergoing surgery on the carotid arteries.