A 10-year-old, spayed female Weimaraner was referred for an acute onset of generalized tremors, seizures, and obtundation. Neurological examination revealed severe obtundation and a right-sided menace response deficit. Neuroanatomical diagnosis was consistent with a left prosencephalic lesion. The serum cardiac troponin I level was high, indicative of acute myocardial necrosis. With magnetic resonance imaging, a mass was observed in the left olfactory bulb and tract, with extensive edema in the white matter of the left cerebrum. The hippocampus was hyperintense on T2-weighted and T2-weighted fluid-attenuated inversion recovery images. At necropsy, a meningioma of the left olfactory bulb and ischemic cell change in the neurons of the hippocampus were identified. In the heart, microscopic lesions consistent with myocardial necrosis were observed. This is the first case to document an elevated cardiac troponin I level in a dog with intracranial disease and myocardial necrosis.