Acute right insular ischaemic lesions and poststroke left ventricular dysfunction

Figure 1. Process of lesion delineation and spatial normalisation. (A) DWI or FLAIR-weighted MR images in original space. (B) The DWI or FLAIR-weighted axial image was used to define the area of ischaemic lesions shown as a red contour and below the red lesion shape. (C) The ischaemic lesion shape and the T1-weighted MRI scans were then transformed into stereotaxic space which generated the normalised map. The normalised lesion map was also applied to the normalised T1-weighted brain to qualitatively demonstrate the accuracy of image normalisation. DWI, diffusion-weighted imaging; FLAIR, fluid-attenuated inversion recovery.

Figure 2. Overlap and distribution of ischaemic stroke lesions of all 231 patients thresholded to include only voxels that were lesioned in at least 5% of the patients. The number of overlapping lesions is illustrated by different colours coding increasing frequencies from dark red to yellow. Regions with higher lesion overlap counts are found in the insular and adjacent opercular regions. Montreal Neurological Institute) coordinates of axial, coronal and sagittal sections are given. L, left hemisphere; N, number of individuals with a lesion in a given voxel; R, right hemisphere.

Figure 3. Results of the voxelwise univariate and multivariate logistic regression analysis showing lesion sites associated with impaired LVEF after stroke. (A) Results of the voxelwise t-test statistics comparing the continuous LVEF parameter between patients who had a stroke with and without lesions in a given voxel. Lesioned voxels in the right insula, amygdala and hippocampus were most prominently associated with decreased LVEF after stroke. An FDR correction of q<0.01 was applied (z-score=3.7). (B) Results of the voxelwise logistic regression analysis comparing LVEF as a categorical parameter adjusted between patients who had a stroke with and without lesions in a given voxel (adjusted for lesion volume and atrial fibrillation). Lesioned voxels in the right insula, adjacent amygdala and hippocampus remained associated with LVEF deterioration after stroke. The independent variable of interest, LVEF, was categorised as normal (>50%), mild impairment (between 35% and 50%), moderate (between 34% and 25%) and severe (<25%). The regressors were ischaemic lesion volume and whether the patient had atrial fibrillation or not. An FDR correction of q<0.05 was applied (z-score=3.3). Only voxels…