The 5-year survival rate with 3-vessel disease plus .95% proximal LAD stenosis was reported to be 59%, as compared with a rate of 79% for 3-vessel disease without LAD stenosis (Table 13). With the use of data accumulated in the 1980s, a nomogram was developed to predict 5-year survival rate on the basis of clinical history, physical examination, coronary angiography, and LVEF (Figure 12). The importance of considering clinical factors and especially LV function in estimating the risk of a given coronary angiographic finding is illustrated by comparing the predicted 5-year survival rate of a 65-year-old man with stable angina, 3-vessel disease, and normal ventricular function with that of a 65-year-old man with stable angina, 3-vessel disease, heart failure, and an EF of 30%. The 5-year survival rate for the former was estimated to be 93%, whereas patients with the same characteristics but with heart failure and reduced EF had a predicted survival rate of only 58%. Because of advances Table 13. CAD Prognostic Index Extent of CAD Prognostic Weight Survival Rate (%)* *Assuming medical treatment only. CAD indicates coronary artery disease; LAD, left anterior descending. Reproduced from Califf et al.55 in treatment, it is almost certain that the survival rate has improved since these studies were conducted, but the relative differences in survival likely persist. The development of symptomatic LV failure in a patient with SIHD is often an indication of severe, obstructive CAD and demands expeditious evaluation for the presence of active ischemia. Depending on the acuity and severity of symptoms, angiography or evaluation for ischemia with noninvasive testing is warranted. 