ON THE urging of his attentive spouse, a 45-year-old man who was previously healthy and entirely asymptomatic reluctantly agrees to undergo a "heart screening" at the local YMCA. This program, supervised by a local cardiologist in the community, consists of risk factor screening and a treadmill exercise test. Within 6 minutes of brisk walking on the treadmill, the man is stopped when the physician overseeing the test notes "an abnormality on the electrocardiogram." He is told that there may be "several heart vessel blockages," that further testing is in order, and that he should schedule an appointment with his own physician immediately. Because the man has not seen a physician since his discharge from military service 15 years earlier, he opts to be examined by the physician supervising the treadmill study.
On the following day, the man undergoes a physical examination; the findings are unremarkable, blood pressure is normal, and