Importance of hemodynamic response to therapy in predicting survival with ejection fraction less than or equal to 20% secondary to ischemic or nonischemic dilated cardiomyopathy. To identify patients with left ventricular ejection fractions less than 20% who are likely to survive on tailored medical therapy after referral to transplantation, this study of 152 patients addressed the hypotheses that (1) severely elevated filling pressures initially measured at referral would not necessarily predict poor outcome, (2) survival would be best when low pulmonary wedge pressures could be achieved with therapy tailored for hemodynamic goals, and (3) coronary artery disease would be an independent risk factor for early mortality. Despite an average initial ejection fraction of 0.15, cardiac index of 2.0 liters/min/m2 and pulmonary artery wedge pressure of 28 mm Hg, the actuarial survival with tailored therapy was 63% at 1 year, with 34 of 41 (83%) deaths occurring suddenly. Survival was not related to initial filling pressure elevation, but was best predicted by the pulmonary artery wedge pressures during therapy; patients achieving pressure of less than or equal to 16 mm Hg had 1-year survival of 83 vs 38% (p = 0.0001). The other independent predictors were serum sodium and coronary artery disease. Patients with high filling pressures during therapy and coronary artery disease had 21% survival at 1 year. Survival after referral to transplantation with an ejection fraction less than or equal to 20% is better than previously described. Patients in whom left ventricular filling pressures cannot be adequately reduced by tailored therapy, particularly if coronary artery disease is present, should be considered for early transplantation. 