That the brain may be involved in cardiovascular regulation has been acknowledged for over a century. That cardiac arrhythmias may result from cortical derangement has been less well recognized. That cortical cardiac representation may be lateralized is even more controversial. Recent evidence implicates several cortical structures, especially the insula, in cardiac rate and rhythm control. Experimental models indicate that insular lesions may be arrhythmogenic. Accumulating data show similar lesion effects in humans. In the rat, monkey and man sympathetic cardiovascular control is generally represented in the right insula, although pronounced insulo-insular connectivity has been demonstrated. Proarrhythmic shifts in cardiac sympathovagal balance occur after human stroke, including left insular lesions. This evidence implicates the cortex in the promotion and even generation of cardiovascular dysfunction under appropriate circumstances.