Risk factors for cerebral embolization after carotid artery stenting with embolic protection: a diffusion-weighted magnetic resonance imaging study in 837 consecutive patients.

BACKGROUND: Meta-analyses of randomized trials have shown an increased risk of periprocedural stroke after carotid artery stenting (CAS) compared with carotid endarterectomy, which may differ in specific patient subgroups. Knowledge of risk factors for cerebral embolic lesions during CAS may impact treatment decisions for the individual patient, but these factors have not been extensively studied. We aimed to identify factors predictive for cerebral ischemic lesions during embolic protected CAS. METHODS AND RESULTS: Preprocedural and postprocedural diffusion-weighted magnetic resonance imaging was performed for evaluation of new cerebral ischemic lesions in 728 (86.9%) of 837 consecutive patients undergoing CAS with cerebral embolic protection. Multivariable logistic regression analyses were performed to identify factors predictive for embolic lesions. New ischemic lesions were found in 32.8% of patients. Age, hypertension, lesion length, lesion eccentricity, and aortic arch type III were significantly associated with new ischemic lesions; calcified lesions were negatively associated. In 25% of these patients embolic lesions were also found in the contralateral hemisphere. Predictive factors for contralateral lesions were age, >50% stenosis of the contralateral internal carotid artery, and an aortic arch type II, with a trend for aortic arch type III. CONCLUSIONS: Age, hypertension, lesion morphology, and aortic arch type were predictive for procedural-related cerebral embolic lesions during embolic protected CAS. Age, significant contralateral carotid stenosis, and complex aortic arch type were predictive for bilateral ischemic lesions. The clinical implications of ischemic lesions are not yet fully understood.

Impact of asymptomatic cerebral lesions in diffusion-weighted magnetic resonance imaging after carotid artery stenting.

OBJECTIVES: This study sought to analyze the impact of new asymptomatic cerebral ischemic lesions, found in diffusion-weighted magnetic resonance imaging (DW-MRI) after carotid artery stenting (CAS) in relation to other risk factors for major adverse cerebral and cardiovascular events (MACCE) defined as death, stroke, and myocardial infarction. BACKGROUND: After CAS, new cerebral lesions have been reported in up to 70% of patients. The impact of asymptomatic lesions on prognosis after CAS has not been studied. METHODS: Eight hundred thirty-seven consecutive patients underwent CAS with cerebral embolic protection. In 728 patients (86.9%), a pre- and post-procedural DW-MRI was available; these patients were included in the analyses. Multivariate Cox regression analysis and Kaplan-Meier estimates were performed to identify independent risk factors for MACCE at follow-up. Clinical, procedural, and lesion characteristics and DW-MRI findings were included in the analyses. RESULTS: Post-procedure new cerebral ischemic lesions were detected in 32.8% (n = 241) of patients. Fifteen patients (1.79%) had a periprocedural MACCE and were therefore excluded from the analysis. At a mean follow-up of 766.8 ± 513.4 days (range 30 to 2,577 days), MACCE occurred in 45 patients (6.2%). Cox regression analysis and Kaplan-Meier estimates both identified diabetes as the only significant independent risk factor of MACCE. Asymptomatic cerebral lesions after CAS were not associated with MACCE. CONCLUSIONS: Beyond 30 days, diabetes is the only risk factor of MACCE at follow-up. Asymptomatic cerebral embolic events after CAS had no prognostic impact.

The PROFI study (Prevention of Cerebral Embolization by Proximal Balloon Occlusion Compared to Filter Protection During Carotid Artery Stenting): a prospective randomized trial.

OBJECTIVES: The objective of this study was to compare the cerebral embolic load of filter-protected versus proximal balloon-protected carotid artery stenting (CAS). BACKGROUND: Randomized trials comparing filter-protected CAS with carotid endarterectomy revealed a higher periprocedural stroke rate after CAS. Proximal balloon occlusion may be more effective in preventing cerebral embolization during CAS than filters. METHODS: Patients undergoing CAS with cerebral embolic protection for internal carotid artery stenosis were randomly assigned to proximal balloon occlusion or filter protection. The primary endpoint was the incidence of new cerebral ischemic lesions assessed by diffusion-weighted magnetic resonance imaging. Secondary endpoints were the number and volume of new ischemic lesions and major adverse cardiovascular and cerebral events (MACCE). RESULTS: Sixty-two consecutive patients (mean age: 71.7 years, 76.4% male) were randomized. Compared with filter protection (n = 31), proximal balloon occlusion (n = 31) resulted in a significant reduction in the incidence of new cerebral ischemic lesions (45.2% vs. 87.1%, p = 0.001). The number (median [range]: 2 [0 to 13] vs. 0 [0 to 4], p = 0.0001) and the volume (0.47 [0 to 2.4] cm(3) vs. 0 [0 to 0.84] cm(3), p = 0.0001) of new cerebral ischemic lesions were significantly reduced by proximal balloon occlusion. Lesions in the contralateral hemisphere were found in 29.0% and 6.5% of patients (filter vs. balloon occlusion, respectively, p = 0.047). The 30-day MACCE rate was 3.2% and 0% for filter versus balloon occlusion, respectively (p = NS). CONCLUSIONS: In this randomized trial of patients undergoing CAS, proximal balloon occlusion as compared with filter protection significantly reduced the embolic load to the brain.

Midterm stability and hemodynamic performance of a transfemorally implantable nonmetallic, retrievable, and repositionable aortic valve in patients with severe aortic stenosis. Up to 2-year follow-up of the direct-flow medical valve: a pilot study.

BACKGROUND: Misplacement during percutaneous aortic valve implantation can be associated with severe complications. The direct flow medical (DFM) valve is repositionable and retrievable; however, the nonmetallic inflatable and conformable design of the valve results in less radial force, which may have an impact on stability and valve function over time. We, therefore, analyzed the midterm stability of the position, shape, and hemodynamic performance of the DFM percutaneous aortic valve. METHODS AND RESULTS: Sixteen symptomatic high-risk for surgery patients with aortic stenosis and a logistic EuroSCORE >20 underwent implantation and were the subject of this analysis. Clinical, echocardiographic, and dual-source multislice computed tomography data were obtained during 2-year follow-up. The 1- and 2-year survival rates were 81% and 69%, respectively. The dual-source multislice computed tomography follow-up indicated no changes in position, diameter, and orifice area of the DFM valve over time. Echocardiography revealed a significant decrease of the mean gradient from baseline (50.1±11.3 mm Hg) to 30 days (19.6±5.7 mm Hg, P<0.001), which remained stable over 2 years. The aortic valve area increased from 0.57±0.15 cm(2) at baseline to 1.47±0.35 cm(2) at 30 days (P<0.001) and did not significantly change during 2-year follow-up. Of the patients, 73% had no aortic regurgitation (AR) and 27% had minimal AR. CONCLUSIONS: In this preliminary series, the 2-year follow-up data of patients, in whom the nonmetallic, repositionable, and retrievable DFM valve was successfully implanted, show stability of the position, shape, and hemodynamic performance, with no AR in most patients.

Carotid artery stenting, what can be learned after more than 1,000 patients: a single centre single operator experience.

AIMS: The aim of the present study was to evaluate the outcome of carotid artery stenting (CAS) in a single, high-volume centre of a single operator and to analyse the circumstances under which complications occur. Recent trials comparing CAS with carotid endarterectomy demonstrated controversial results. The low experience of interventionists in performing CAS was a major limitation of these studies. The number of procedures needed to achieve optimal skills is unknown. METHODS AND RESULTS: From May 1997 until April 2010, 1,004 patients with symptomatic or asymptomatic carotid artery stenosis underwent CAS by a single operator. A cerebral protection device was in mandatory use since 2000. In-hospital complication rates were defined as the cumulative rate of death, myocardial infarction or stroke. Procedural success was achieved in 97.77% of patients. The perioperative complication rate was 1.69% including 0.2% deaths, 1.1% patients with minor stroke, 0.4% patients with major stroke. In 88% (15 out of 17) of the patients with complications, unfavourable anatomical or procedural factors could be identified. After the first 100 CAS performed,the complication rate was at 3% and significantly decreased to 1% after more than 500 procedures. Patients ≥80 years had a significantly higher complication rate. CONCLUSIONS: In a high-volume experienced centre, the in-hospital complication rate is low. Complications occurred almost exclusively in patients with unfavourable anatomical or procedural characteristics and seem to be avoidable in most patients. A learning curve was observed up to 500 procedures. Elderly patients have a higher complication rate.