Identification of Epigenetic Risk Factors for Ischemic Complication During the TAVR Procedure in the Elderly

The neurological lesions detected on cerebral MRI caused by these endovascular procedures are frequent with an incidence of about 30-70%. These events, although subclinical, have an impact on morbidity and mortality and especially on long-term cognitive decline.

TAVR is the reference treatment for symptomatic elderly patients with stenosis of the aortic valve, considered by a multidisciplinary "Heart Team" as at high surgical risk due to comorbidities, age and high perioperative risk scores ( Euroscore 2 and STS scores). Despite the net clinical benefit, an increase of silent neurological events was detected on post-procedural cerebral MRI with an incidence of approximately 70%.

The epigenetic involvement in the occurrence of ischemic cerebral lesions is still largely unknown. Epigenetic mechanisms, such as DNA methylation, can be associated with aging processes and modulate the risk of developing cerebrovascular pathologies. They are likely to provide new biomarkers that predict the risk of brain damage.

Hypomethylation of leukocyte DNA is directly related to atherosclerosis in humans. This hypomethylation of DNA would represent an easily measurable marker reflecting the presence and progression of atherosclerosis. Because atherosclerotic lesions often precede the clinical manifestation of ischemic cardiovascular disease, such as ischemic heart disease and stroke, DNA hypomethylation could be used to identify individuals at risk for cerebrovascular events.

The investigator hypothesize that hypomethylation of leukocyte DNA can predict the risk of developing new ischemic brain lesions especially after a TAVI procedure.