2008 Stroke Council Award and Lecture—Brain and Heart: The Good, the Bad, and the Different
The brain and the heart are unique and essential organs, with autoregulated blood supplies and sophisticated electrical systems, functioning with harmonious complementarity in health; however, disease of one organ can threaten the other. Cardiac valvular disease, atrial fibrillation, and acute myocardial infarction carry a risk of stroke, and both ischemic and hemorrhagic strokes can lead to cardiac abnormalities and sudden death.
Heart disease and stroke share most of the same risk factors, but not to the same degree, nor necessarily with the same consequences. For example, hypertension represents the single most powerful risk factor for stroke and can result in a major intracerebral hemorrhage, a condition without equivalent in any other organ. Despite the superficial resemblance between angina and transient ischemic attack, the mechanisms differ. Angina can be brought on by exercise, but no amount of mental exercise will lead to “brain angina.” Most cardiac patients can maintain a reasonable quality of life on half of their cardiac output. No meaningful quality of life is likely with half of brain output. Stroke recovery is complex. The brain is the only organ with which one can communicate directly and whose feelings have to be considered in recovery. Although stroke and heart disease prevention have much in common, puzzling differences remain. In primary prevention, aspirin prevents heart attacks in men but not in women, and strokes in women but not in men.
Given the great commonalities and interrelationships between vascular brain and heart disease, it has been sensible and successful to have one organization encompassing cerebrovascular and cardiovascular health and diseases. To continue to progress at an accelerated pace, we need to become more familiar with the mutual relationship between cerebrovascular and cardiovascular disease, work together where we can, and separately where we must, but with the common aim of vanquishing both.