Cerebral Embolism : A Silent Iatrogenic Complication of TAVR That Needs Voiced Consideration

Transcatheter aortic valve replacement (TAVR) has rapidly and definitely changed the way patients with aortic stenosis are treated. Both the number of procedures and the indications have increased worldwide, allowing the inoperable patient to be treated, the high risk patient to be treated less invasively, and the intermediate risk patient to have the choice of an alternative to surgery. Clinical stroke or transient ischemic attack is not uncommon after aortic stenosis treatment, ranging in the randomized studies from 5% to 6% at 30 days to 8% to 10% at 1 year—one-half of them being major/disabling strokes. Current registry data report a 3.5% stroke rate at 30 days, which represents almost a 50% decrease as compared to early experience with TAVR. In addition, stroke related to TAVR appears to be less frequent than stroke with surgical aortic replacement. However, clinical stroke is only the emerging part of the iceberg. Silent cerebral embolism (CE) following TAVR is the hidden part of this iceberg occurring in three-quarters of the cases, regardless of the device or vascular access used. If the prognosis impact of clinical stroke is well established, the potential long-term deleterious impact of silent CE remains unknown. Whereas silent brain infarctions are known to be associated with cognitive decline and dementia, long-term cognitive performance appears to be preserved in >90% of TAVR patients despite a high intrinsic risk for cognitive deterioration. However, poor information and the absence of long-term controlled evaluation keep the problem mostly invisible as TAVR indications now reach lower-risk and/or younger patients. Better understanding, detection, and identification of preventive measures of TAVR-related CE are needed.