Early detection of life-threatening heart disorders, stroke and other diseases is possible through the use of vascular testing procedures performed within hospitals, outpatient centers and physicians' offices. Cardiovascular diseases are the No. 1 cause of death in the United States. On average, one American dies every 39 seconds of cardiovascular disease - disorders of the heart and blood vessels. Stroke, a disorder of the blood supply to the brain, is the third leading cause of death and the leading cause of disability in the country, with nearly 800,000 new strokes occurring annually.