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.