Higher LV Mass Index Associated With Compromised White Matter Microstructure

In older adults with symptoms of dementia, an increased left ventricular (LV) mass index may be associated with compromised white matter microstructure, indicating an association between LV remodeling and vulnerability of cerebral white matter microstructure in these individuals, according to a study published in the Journal of the American Heart Association.

Participants from the Vanderbilt Memory & Aging Project who were free of dementia, clinical stroke, and heart failure were enrolled (n=318). Participants underwent brain magnetic resonance imaging, cardiac magnetic resonance, and neuropsychological evaluations. The neuropsychological assessment evaluated language, executive function, episodic memory, and visuospatial skills. Investigators also collected data on systolic and diastolic blood pressure, antihypertensive medication use, diabetes mellitus, age, sex, Framingham Stroke Risk Profile, and apolipoprotein E-e4 status.

There was a negative correlation between LV mass index and fractional anisotropy in the superior frontal gyrus (P <.049) and a positive association between LV mass index and mean diffusivity in the anterior corona radiata (corrected P =.003). There was no association between LV mass index and cognitive diagnosis on any diffusion tensor imaging measure (corrected P >.3); however, the investigators did observe an association between LV mass index and neuropsychological performance.

Specifically, there was an observed association between LV mass index and worse visuospatial memory performance (P =.036), even after excluding atrial fibrillation, cardiovascular disease, and LV hypertrophy. An increased LV mass index was also associated with alterations in the white matter microstructure (P <.05). Associations were found between the LV mass index and diffusion tensor imaging in participants with mild cognitive impairment (P <.05).

The cross-sectional nature of the study limited the researchers’ ability to determine causality.

According to the study investigators, understanding the observed associations “between subclinical cardiac structural changes and early alterations in white matter may allow for early detection and prevention of white matter damage, particularly among those with cognitive decline, in whom existing pathology may exacerbate these changes.”

Reference

Moore EE, Liu D, Pechman KR, et al. Increased left ventricular mass index is associated with compromised white matter microstructure among older adults. J Am Heart Assoc. 2018;7(13). doi:10.1161/JAHA.118.009041