The PROFI Study (Prevention of Cerebral Embolization by Proximal Balloon Occlusion Compared to Filter Protection During Carotid Artery Stenting): A Prospective Randomized Trial

Study Questions:

What is the comparative efficacy of filter-protected versus proximal balloon–protected carotid artery stenting (CAS) in reducing cerebral embolic load?


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 (DW-MRI). Secondary endpoints were the number and volume of new ischemic lesions and major adverse cardiovascular and cerebral events (MACCE). Continuous variables were presented as mean ± standard deviation, and Mann-Whitney and Student t tests were used, as appropriate. Categorical variables were compared using the Fisher exact test.


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 [0-13] vs. 0 [0-4], p = 0.0001) and the volume (0.47 [0-2.4] cm vs. 0 [0-0.84] cm3, 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).


The authors concluded that proximal balloon occlusion as compared with filter protection significantly reduced the embolic load to the brain.


This study suggests that in patients undergoing carotid artery stenting, proximal balloon occlusion significantly reduces the incidence of new cerebral ischemic lesions compared with filter protection, as assessed by DW-MRI, and reduced the incidence of new ischemic lesions by a factor of 1.9. If the findings of the present study translate to a lower clinical stroke rate in randomized trials, proximal occlusion would become the preferred emboli protection strategy. It should be noted that although imaging studies suggest less intracranial embolization with proximal balloon than filter protection, the overall risk of stroke is low with both techniques.

Clinical Topics: Invasive Cardiovascular Angiography and Intervention, Noninvasive Imaging, Vascular Medicine, Interventions and Imaging, Interventions and Vascular Medicine, Magnetic Resonance Imaging

Keywords: Students, Stroke, Endarterectomy, Carotid, Magnetic Resonance Imaging, Vascular Surgical Procedures, Stents, Incidence, Carotid Artery, Common, Filtration, Balloon Occlusion, Cardiology, Carotid Stenosis, Brain

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