Appraisal of the double two-step exercise test. A long-term follow-up study of 3,325 men

We made an evaulation of the double two-step exercise test in the diagnosis and prognosis of coronary artery disease, on the basis of the findings among 3,325 male applicants for life insurance who were given the test and observed for an average of nine years. The results suggest that (1) ischemic ST segment depression of any amount after exercise is pathognomonic of coronary insufficiency, for all practical purposes; (2) the amount of ischemic depression is related to the severity of the coronary insufficiency and the prognosis; (3) ischemic depression in multiple leads denotes widespread coronary insufficiency; (4) a nonischemic response practically excludes coronary disease of a type that will cause premature death; and (5) the exercise test is more reliable than the medical history in the diagnosis of silent coronary disease.