Effect of the transmural extent of myocardial scar on left ventricular systolic wall thickening during intravenous dobutamine administration.

Using magnetic resonance imaging, the extent of scar tissue due to chronic infarction and quantification of dobutamine systolic wall thickening (SWT) can be measured simultaneously in human subjects. To determine whether the transmural extent of scar tissue determines dobutamine SWT in chronic ischemic heart disease, we assessed the transmural extent of hyperenhancement and dobutamine SWT with magnetic resonance imaging in 16 patients. The transmural extent of hyperenhancement correlated inversely with dobutamine SWT (r = -0.7, p <0.001). All segments with dobutamine SWT >/=2 mm showed a transmural extent of hyperenhancement of <50%.