The prognostic significance of 50% coronary stenosis in medically treated patients with coronary artery disease.

In this study we determined the prognostic significance of 50% coronary stenosis in 1183 medically treated patients with coronary artery disease. Clinical outcome was measured by survival and eventfree (freedom from death and infarction) rates. Significant disease was first defined as 75% or greater narrowing. In 225 patients with less than 75% narrowing of all vessels, including 68 patients with 50% stenosis of at least one vessel, the 3-year survival rate was 100%. Patients with one, two or three significantly (75% or greater) stenosed vessels with additional 50% stenosed vessels had the same outcome as patients with one, two or three diseased vessels without additional 50% stenosed vessels. Significant disease was then defined as 50%