TRAnscranial Doppler CErebral Blood Flow and Cognitive IMPAIRment in Heart Failure

Circumstantial evidence suggests that cognitive dysfunction may occur in HF patients as often undiagnosed comorbidity. Cognitive dysfunction may aggravate HF symptoms and influence prognosis. Cognitive dysfunction may be a reason for inadequate self-care and poor symptom control (e.g., weight gain monitoring). In addition, it may affect medication compliance, leading to hospital readmissions and increased mortality. Brain tissue hypoxia, microemboli, silent strokes, and co-existing anemia have been implicated in contributing to cognitive dysfunction in HF. However, the role of cerebral flow impairment in these patients remains unclear. This uncertainty is mainly because previous studies included small patient groups, diverse imaging techniques, and neuropsychological tests. Furthermore, these studies were primarily conducted in the elderly, a potentially important confounder due to the effect of age on cognitive dysfunction. Particularly little data is available for younger patients (< 60 years).

This study aims to investigate the association of HF, carotid and cerebral flow, and cognitive impairment. Consecutive patients with HF with mildly reduced (HFmrEF) and reduced ejection fraction (HFrEF) will be included in the study. Echocardiography with routine measurements such as ejection fraction and stroke volume will be performed in each patient. The carotid and cerebral flow will be assessed on Doppler ultrasonography. Each patient will undergo cognitive function assessment using Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA). The results in the index group (isolated HF) will be compared with those in a group of patients with HF and flow-limiting carotid stenosis (CS) against a control group (no HF, no CS).

Inclusion criteria

• Clinically stable patients (NYHA I-III symptoms) with HF (for at least 6 months) either of ischemic or inflammatory etiology as well as genetic cardiomyopathies
• Signed informed consent form
• Consent to imaging studies: echocardiography, carotid and transcranial Doppler sonography and neuropsychological tests (MMSE and MoCA).

Exclusion criteria

• Co-existing, severe, irreversible disease (e.g. advanced cancer)
• Previously diagnosed dementia (including severe dementia - MMSE and MoCA score <10)
• Psychiatric condition which may influence cognitive function
• Acute, decompensated HF
• Reversible cause of HF - tachyarrhytmic, peripartum or toxic cardiomyopathy, acute myocarditis, acute myocardial infarction
• Aortic stenosis
• Cerebral stroke in the preceding 3 months
• Lack of transcranial Doppler acoustic window
• Echocardiographic projections precluding adequate measurements
• Anemia with Hemoglobin < 8 g/dl
• Alcohol or psychoactive agents abuse