An Integrated Multimodal Approach to Evaluate Autonomic Control, Cerebral Autoregulation and Cognitive Function in Patients Undergoing Surgical Aortic Valve Replacement during a 3-Months Follow-up

Abstract

Surgical aortic valve replacement (SAVR) can have an impact on cardiovascular (CV) and cerebrovascular (CBV) controls and their impairment could be related to the occurrence of post-surgery CBV adverse events such as stroke. This study proposes a multimodal approach to evaluate the impact of SAVR on different physiological districts. CV and CBV control markers in time, frequency and information domains were computed from the variability of heart period, systolic and mean arterial pressure, and mean cerebral blood flow velocity. Recordings were performed during active standing before (PRE) surgery, within one week from surgery (POST) and after a 3-month follow-up (POST3) in 56 patients (age: $65 \pm 13$ yrs, 38 males) undergoing SAVR. Cognitive function was evaluated via psychological tests at every time point, while the presence of ischemic lesions was evaluated at POST via diffusion-weighted magnetic resonance imaging (DW-MRI). Findings showed that CV control indexes were affected in POST and recovered at POST3. DW-MRI indicated the presence of recent ischemic lesions in a high percentage of patients but their cognitive function as well as CBV control was preserved at all time points. A multimodal approach integrating time series analysis, psychological tests and classical imaging techniques could provide an accurate monitoring of postoperative recovery and the identification of patients at risk of developing post-surgery CBV adverse events.