Reduced relative harmonic power of diastolic cardiovascular impulses in Alzheimer’s disease

Motivation: Alzheimer's disease (AD) links to altered cerebrovascular brain impulse properties. Understanding these changes provides insights into AD's impact on brain physiology. Goal(s): This study aims to develop a frequency domain relative harmonic power (MREGRHP) method to analyze the variability of diastolic effects such as aortic notch on brain pulsations unaffected by MR signal intensity or impulse amplitude itself. Approach: We optimized detection of cardiac waveforms using fast fMRI to boost cerebrovascular signal-to-noise ratio. Results: MREGRHP showed reduced harmonic power in frontoparietal areas of AD patients, suggesting altered diastolic impulse patterns and increased propagation speed in brain regions usually affected by AD. Impact: This study introduces new method, a frequency-based approach to assess cardiovascular brain impulses in Alzheimer's disease (AD) patients. Findings reveal altered impulse patterns in regions usually affected by AD, offering potential biomarkers for understanding AD's impact on brain hydrodynamics.