Patients treated with Carotid artery stenting for symptomatic or asymptomatic carotid arterial stenosis were consecutively enrolled. Residual stenosis was estimated from post-procedure angiography findings. The effects of residual stenosis on 30-day periprocedural outcome and times to restenosis and clinical outcome were analyzed using logistic regression models and Wei-Lin-Weissfeld models, respectively.
A total of 412 patients (age, 64.7 ± 17.0 years; male, 82.0%) were enrolled. The median baseline stenosis was 80% (interquartile range [IQR], 70-90%), which improved to 10% (0-30%) for residual stenosis. Residual stenosis was significantly associated with periprocedural outcome (adjusted odds ratio, 0.983; 95% confidence interval [CI], 0.965-0.999, P = 0.01) after adjustment for baseline stenosis, age, hypertension, symptomaticity, and statin use. Over the 5-year observation period, residual stenosis did not increase the global hazard for restenosis and clinical outcome (adjusted hazard ratio, 1.011; 95% CI, 0.997-1.025. In the event-specific model, residual stenosis increased the hazard for restenosis (adjusted hazard ratio, 1.041; 1.012-1.072) but not for clinical outcome (adjusted hazard ratio, 1.011; 0.997-1.025).
Residual stenosis after carotid artery stenting may be useful to predict periprocedural outcome and restenosis 1).
Sixty-seven consecutive procedures were performed for internal carotid artery stenosis with CAS at the hospital between November 2015 and February 2018. Procedures for emergency CAS for stroke in evolution or crescendo transient ischemic attack were excluded (n = 12). The embolic debris from remaining procedures (n = 55) was stained with hematoxylin-eosin and the red blood cells, white blood cells, and fibrin were quantified by color-based segmentation. Cholesterol crystals and calcification were examined histopathologically. Diffusion-weighted imaging (DWI) was performed 1-3 days after CAS, and the images were used to classify procedures according to the presence of new lesions.
Of the 55 CAS procedures, new DWI lesions were identified after 32. One patient had symptomatic cerebral embolism. Higher proportions of patients with cholesterol crystals in embolic debris (17 vs. 78%, p < 0.001) and higher proportion of white blood cells (mean 2.3 [0-9.9] vs. 4.2% [0-29.9%], p < 0.01) were observed in the embolic debris of procedures with and without new DWI lesions.
Cholesterol crystals were common in the embolic debris from patients with postoperative ischemic lesions after CAS. These results suggest that inflammatory destabilization of the intraplaque lipid component is related to postprocedural DWI lesions 2).
A clinical study included 43 patients with carotid artery stenting. Cervical computed tomography (CT) images obtained on a 320-slice scanner were reconstructed with AIDR 3D and FIRST. Five blinded observers visually graded the likelihood of neointimal formations on AIDR 3D and AIDR 3D plus FIRST images. Carotid ultrasound images were the reference standard.
Yokomachi et al., analysed results of visual grading by using a Jack-knife type receiver observer characteristics analysis software.
In the phantom study, the difference between the measured and the true diameter of the neointimal formations was smaller on FIRST than FBP or AIDR 3D images. In the clinical study, the sensitivity, specificity, positive predictive value, negative predictive value and accuracy of AIDR 3D were 58%, 88%, 83%, 67% and 73%, respectively. For AIDR 3D plus FIRST images they were 84%, 78%, 80%, 82% and 81%, respectively. The mean area under the curve was significantly higher on AIDR 3D plus FIRST than AIDR 3D images (0.82 vs 0.72; p < 0.01).
The model-based IR algorithm helped to improve diagnostic performance for the detection of neointimal formations after carotid artery stenting 3).
A study from Shchanitsyn et al., was aimed at comparative analysis of the transradial versus transfemoral approach used in carotid stenting. They retrospectively analysed the results of transradial and transfemoral stenting of carotid artery in a total of 168 patients. The operations had been performed in two centres over the period from 2012 to 2017. They evaluated the clinical and angiographic data, technical aspects of the operations, as well as the outcomes and complications. In particular, they compared such complications as stroke, transient ischemic attack, myocardial infarction and local complications of the approach. They carried out a univariate analysis of the risk for the development of complications depending on the method of the approach. Stenting of carotid arteries had been performed in 75 patients through the radial artery approach and in 93 patients via the femoral one. Comparing the two groups, the main clinical and angiographic data appeared to have no statistically significant differences. Various techniques of catheterization had been used depending upon anatomical peculiarities. The success of the procedure was achieved in 100% of cases, with the frequency of conversion amounting to 4% for the radial approach and to 1% for the femoral one (p=0.087). Amongst complications encountered, disabling stroke was revealed in two (1.2%) patients and minor stroke in four (2.4%). The groups did not differ by the incidence of neurological complications. Within 30 postoperative days neither lethal outcomes nor myocardial infarction were registered. Neither were there haemorrhagic events or other approach-related complications, however in the transradial-approach group, seven (9.3%) patients were found to have developed asymptomatic occlusions of the radial artery. The duration of the operation, the radiation load, and the length of hospital stay had no statistically significant differences depending on the approach used. Hence, the transradial approach is an effective and safe method in stenting of carotid arteries. In patients with high risk of haemorrhagic complications from the side of the vascular approach and with difficult anatomy of the aortic arch and its branches, hampering catheterization of the carotid artery via the femoral approach, the radial artery may be considered as an advantageous site of access 4).
Four patients (5 stenotic lesions) with stenosis of the common carotid artery (CCA) origin underwent transfemoral stenting with a balloon protection device (PercuSurge GuardWire; Medtronic, Santa Rosa, California). These 5 stenotic lesions of the CCA origin included 1 on the right side and 4 on the left side. Two of the stenoses were symptomatic, and 3 were asymptomatic. A balloon-expandable stent (Express LD stent; Boston Scientific, Natick, Massachusetts) was used in all patients.
All stenoses were successfully dilated. With the balloon protection device as an anchor in all patients, the guiding catheter was highly stable during the procedure. There were no intraprocedural or periprocedural ischemic complications in any patients. None of the patients developed a stroke during a mean follow-up period of 8.4 months.
The anchoring technique using a balloon protection device is useful for transfemoral stenting of stenoses at the CCA origin 5).
For a period of 28 months, 31 patients with carotid artery stenosis , most of whom were considered at high risk for carotid endarterectomy (CEA) (87%), underwent treatment with CAS in conjunction with either the PercuSurge GuardWire (n = 19; Medtronic, Minneapolis, Minn), the Cordis Angioguard filter (n = 7; Cordis, Warren, NJ), or the ArteriA Parodi Anti-embolization catheter (n = 4; ArteriA, San Francisco, Calif) with US Food and Drug Administration-approved investigational device exemptions. Factors that made CEA high risk included restenosis after CEA (n = 6), hostile neck (n = 6), high or low lesions (n = 4), and severe comorbid medical conditions (n = 11). Preoperative neurologic symptoms were present in 58%, and the mean stenosis was 85% +/- 12%. Data were prospectively recorded and analyzed on an intent-to-treat basis. Neurologic evaluation was performed before and after carotid artery stenting CAS by a protocol neurologist.
CAS was performed with local anesthesia with the Wallstent (n = 23; Boston Scientific Corp, Natick, Mass) or the PRECISE carotid stent (n = 7; Cordis) in conjunction with one of the protection devices in an operating room with a mobile C-arm. Each patient received dual antiplatelet therapy before surgery. The overall technical success rate was 97% (30/31). In one patient, the lesion could not be crossed with a guidewire because of a severely stenosed and tortuous lesion. This patient was not a candidate for CEA and was treated conservatively. In the remaining 30 cases, CAS had a good angiographic result (residual stenosis, <10%). All patients tolerated the protection device well, and no intraprocedural neurologic complications occurred. Macroscopic embolic particles were recovered from each case. One patient (3%) with a severely tortuous vessel had a major stroke immediately after CAS, and no deaths occurred. The combined 30 day stroke/death rate was 3%. During a mean follow-up period of 17 months, one subacute occlusion of the stent occurred but did not result in a stroke. Three other patients had duplex scan-proven in-stent restenosis, and two underwent treatment with repeat percutaneous transluminal angioplasty with a good result. No patient had a stroke during the follow-up period.
CAS with cerebral protection devices can be performed safely with a high technical success rate. Although many patients who underwent treatment with CAS were at high risk, the neurologic complication rate was low and CAS appears to be an acceptable treatment option for select patients at high risk for CEA. Tight lesions and tortuous anatomy may make the use of distal protection devices difficult. Further study is warranted 6).