Cognitive Outcome After Surgical and Transcatheter Aortic Valve Replacement

Aortic valve stenosis is one of the most common types of heart disease in the aging Western population. While surgical cardiac valve replacement (SAVR) is a standard therapy for patients with aortic stenosis, catheter-assisted aortic valve implantation (TAVI) has developed as an alternative to open-heart surgery, especially for high-risk patients. Recently, increased surgeon experience and improved transcatheter valve systems have led to a global trend to use TAVI in patients with low or intermediate risk. Although cognitive impairment after cardiac surgery is well known, the effect of TAVI on cognitive function has not yet been adequately investigated. The aim of this study is to compare the occurrence and progression of delirium, postoperative cognitive decline (POCD), cerebral infarction, and health-related quality of life (QOL) in patients with intermediate risk for catheter-assisted (TAVI) and surgical (SAVR) aortic valve replacement.

The present project is a substudy of the DEDICATE Trial (ID: NCT03112980). It is a randomized intervention study taking place at the Kerckhoff-Klink Bad Nauheim Germany (Campus Justus Liebig University Giessen) involving 100 patients undergoing aortic valve replacement (TAVI vs. SAVR) with a focus on cognitive outcome. A detailed assessment of psychological and health-related functions will be performed before intervention, during hospitalization and 3 months after intervention. During hospitalization, the occurrence and progression of delirium will be assessed with the Intensive Care Delirium Screening Checklist (ICDSC). Other cognitive data will be collected before and 3 months after surgery with a selected and comprehensive neuropsychological test battery, including the evaluation of attention, word fluency, executive functions and various functional areas of memory. In addition, parameters of health-related QOL will be collected before and 3 months after the intervention using the SF-36, and information on anxiety and depression will be collected using the Hospital Anxiety and Depression Scale (HADS). A few days after the intervention, magnetic resonance images of the brain will be acquired to assess cerebral infarction.

Eligibility Criteria:
Inclusion Criteria:

1. Heart team decision that both TAVI and SAVR are medically justified based on

   * Degenerative aortic valve stenosis:

     * Mean gradient \> 40 mmHg or
     * Jet velocity \> 40 m/s or
     * Surface of aortic valve \< 1.0 cm²
   * Patient shows symptoms of aortic stenosis

     * NYHA functional class ≥ II or
     * Angina pectoris or
     * Syncope
   * Low to intermediate surgical risk (STS: 2-6%)
   * A transfemoral or alternative access for TAVI can be implemented
2. Patient has agreed in writing to participate in the study
3. Patient is able to understand the patient information and sign it personally
4. Patient agrees to undergo SAVR if randomization into the control group occurs
5. Readiness for MRT examination and neuropsychological testing after 3 months
6. Patients aged 65 to 85 years.
7. Native German speaker (since a neuropsychological test is language dependent)

Exclusion Criteria:

1. Congenital aortic valve defects
2. Untreated clinically significant coronary artery disease or severe mitral or tricuspid insufficiency or mitral stenosis
3. Previous heart surgery
4. Percutaneous coronary intervention performed within one month prior to the study
5. Hemodynamic instability requiring inotropic support or mechanical circulatory support
6. Ischemic stroke or intracranial bleeding within the month before the start of the study
7. Severe ventricular dysfunction with left ventricular ejection fraction \< 20% as measured by echocardiogram
8. Hypertrophic obstructive cardiomyopathy or severe basal septum hypertrophy
9. Echocardiographic detection of intracardiac mass, thrombus, vegetation, or endocarditis
10. Any other atherosclerotic disease that is considered as a contraindication for isolated aortic valve surgery
11. Symptomatic carotid or vertebral artery disease
12. Existing neurological or psychiatric disease (particularly cerebral infarction, cranio- cerebral trauma, manifest depression or dementia) that may interfere with neuropsychological testing.
13. Contraindications for MRI examination (e.g. cardiac pacemaker, vena cava filter, claustrophobia)