Identification of new instances of white matter hyperintensities in patients following TAVI (from the CAPITA study)

Abstract A third of patients diagnosed with symptomatic severe aortic valve stenosis and scheduled for transcatheter aortic valve implantation (TAVI) exhibit some level of cognitive impairment. The prospective CAPITA study aimed to systematically evaluate the impact of TAVI on cerebral and cognitive outcomes in patients undergoing the procedure. In this report, we focus on the identification of new incidence of white matter hyperintensities (WMH) and the correlation with changes in cognitive functioning. The CAPITA (CArdiac OutPut, Cerebral Blood Flow and Cognition In Patients With Severe Aortic Valve Stenosis Undergoing Transcatheter Aortic Valve Implantation) study is a prospective study of cerebral and cognitive outcomes following TAVI. Patients underwent magnetic resonance imaging (MRI) and extensive neuropsychological testing at baseline and three month follow-up. New cerebral infarcts were defined according to NeuroARC criteria. We examined the incidence of new WMH in terms of volume (Δ mL) and number on FLAIR MRI, and explored the correlation between new WMH and cognitive functioning. A total of 148 patients were included who underwent TAVI between August 2020 and October 2022. Mean age was 80.5±5.7 years, of whom 43% female with a median STS-PROM of 2.0% (IQR 1.4%-2.9%). Median baseline WMH comprised 127 (IQR 32-216) lesions, with a total volume of 13.1 (IQR 7.0-24.6) mL. At 3 months follow-up, the number of lesions increased to 164 (IQR 121-301) lesions, with a total volume of 13.3 (IQR 5.8-21.5) mL. Median WMH volume increase was 0.1 (IQR 0.0-0.3) ml (p=0.02). A total of 9 patients (9.5%) had an increase of 1 mL of WMH or more. At follow-up, 12% of patients exhibited cognitive decline of >0.5SD. These patient tended to have a greater increase in white matter hyperintensity volume (1.26±2.96 ml), compared to the 53% of patients with stable cognition (0.29±0.45 ml) and the 36% of patients with improved cognition (0.31±0.91 ml), (p=0.06). WMH lesions did not exhibit distribution patterns across various locations within the groups characterized by declined, stable, or improved cognition (Figure 1). WMH volumes were higher in patients who experienced postprocedural delirium than in patients without delirium (27.1±14.0 vs 15.0±12.5 mL, p<0.001). In this study, patients with severe symptomatic aortic valve stenosis undergoing TAVI, there was an overall increase of white matter hyperintensity volume between baseline and 3-month follow-up. Up to 12% of patients had cognitive decline, which was associated with new white matter hyperintensities on MRI.