Rationale: Cardiovascular disease and cognitive diseases are closely related. Cognitive impairment is common (21-39%) among patients with severe aortic valve stenosis. The proof-of-concept CP-TAVI study showed that increased cardiac output following transcatheter aortic valve implantation (TAVI) was associated with increased cerebral blood flow. It is hypothesized that increased cerebral blood flow (CBF) subsequently leads to improved cognitive functioning. Additionally, silent micro emboli caused by crushing of the calcified native valve during TAVI may cause cognitive deterioration. If it could be predicted which patients are at risk for TAVI induced cerebral micro emboli, these patients could benefit from cerebral protection devices, preventing cognitive decline.

Objective: The objectives of the CAPITA study are 1A) to identify whether an increase in cardiac output after TAVI is associated with an increase of global CBF; 1B) explore regional differences in CBF after TAVI; 1C) determine whether (global or regional) increased CBF is associated with improved cognitive functioning; 1D) identify patient and procedural characteristics associated with increased cardiac output, CBF and cognitive functioning; 2A) identify the incidence and volume of new white matter hyperintensities after TAVI; 2B) evaluate patient and procedural predictors for the increase in white matter hyperintensities volume, including baseline aortic valve calcification volume, measured with computed tomography; 2C) if aortic valve calcification volume predicts new white matter hyperintensities, define a cut-off value for high-risk patients; 2D) assess whether the increase in white matter hyperintensity volume is associated with deterioration of cognitive scores.

Study design: Prospective observational study, measuring cardiac output (echocardiography), cerebral blood flow (arterial spin labelling magnetic resonance imaging) and cognitive functioning (neuropsychological test battery) prior to TAVI (<24 hours to \

Inclusion Criteria:

• Severe aortic valve stenosis (aortic valve area <1cm2 and/or mean aortic valve gradient exceeds 50 mmHg) of a native valve
• Eligible for TAVI
• Able and willing to give informed consent
• Age > 18 years

Exclusion Criteria:

• Presence of MRI contra-indication; inability to lay flat for 30 minutes
• Weight > 130 kg
• Neurological disease
• Active malignant disease;
• Insufficient mastery of the Dutch language
• Inability to withdraw from alcohol use for 24 hours
• Non-atherosclerotic vascular disease (eg vasculitis)
• Planned surgery with general anesthesia within three months after TAVI.

N=142 patients with symptomatic severe aortic valve stenosis selected for transcatheter aortic valve implantation