An investigation of changes in regional gray matter volume in cardiovascular disease patients, pre and post cardiovascular rehabilitation

Abstract

Cognitive function decline secondary to cardiovascular disease has been reported. However, little is known about the impact of coronary artery disease (CAD) on the aging brain macrostructure or whether exercise training, in the context of cardiovascular rehabilitation, can affect brain structure following a coronary event. This study employed voxel-based morphometry of high resolution structural MRI images to investigate; 1) changes in regional gray matter volume (GMV) in CAD patients compared to age-matched controls, and 2) the effects of a six-month exercise-based cardiovascular rehabilitation program on CAD-related GMV decline. Compared to controls, significant decreases in regional GMV were found in the superior, medial and inferior frontal gyrus; superior and inferior parietal gyrus; middle and superior temporal gyrus and in the posterior cerebellum of CAD patients. Cardiovascular rehabilitation was associated with the recovery of regional GMV in the superior frontal gyrus, superior temporal gyrus and posterior cerebellum of the CAD patients as well as the increase in GMV in the supplementary motor area. Total and regional GMV correlated with fitness level, defined by the maximal oxygen consumption (VO2max), at baseline but not after cardiovascular rehabilitation. This study demonstrates that cardiovascular disease can adversely affect age-related decline in GMV; and that these disease-related effects could be mitigated by moderate levels of exercise training as part of cardiovascular rehabilitation.

Keywords: CAD, Coronary artery disease; CR, Cardiovascular rehabilitation; Coronary artery disease; Exercise training; GMV, gray matter volume; METs, metabolic equivalents; MoCA, Montreal Cognitive Assessment; Neuroplasticity; Regional brain atrophy; VBM, voxel-based morphometry; VO2max, maximal oxygen consumption; Voxel-based morphometry.

Fig. 1

Differences in GMV between CAD patients and age-matched controls measured at baseline. t-Statistics displayed on a rendered model of a single subject brain. The red blobs on coronal, sagittal and transverse planes indicate areas of decreased GMV in the CAD patient group.

Fig. 2

GMV changes over time in CAD patient pre and post CR. t-Static displayed on a rendered model of a single subject brain. Red blobs on coronal, sagittal and transverse planes indicate areas of increased GMV in the CAD group after 6 months of CR.