The natural history of patients with ischemic heart disease varies widely depending upon the anatomic lesion and extent of left ventricular dysfunction. Several clinical variables may also be used to help determine the likelihood of long-term survival. Individuals with high-grade isolated disease of the left anterior descending coronary artery, without significant impairment of ventricular function, have little morbidity and mortality for the 2-year period after arteriography. At the other end of the spectrum, medically treated patients with stenosis of the left main coronary artery or three-vessel disease without such involvement have a reduced life expectancy compared with patients treated surgically. Global judgments on long-term results of the medical treatment of coronary artery disease are meaningless. Efforts should be made to delineate optimal treatment for various subgroups of patients under the broad rubric of ischemic heart disease.