Cardiopulmonary exercise test has been raised through recent decades as a brilliant prognostic tool in a wide field of diseases and clinical conditions which makes it valuable to be used in prognostic assessment during the current study among chronic heart failure (CHF) patients. This study recruited 71 patients with severe CHF who were candidates for heart transplantation. Bicycle-protocol Cardiopulmonary Exercise Test was done, and several parameters were measured and compared between four groups of patients based on their VO2/kg to show four grades of the disease from G1 to G4. Total 71 CHF subjects from 18 to 46 year of age enrolled in the study. Statistically significant correlations were determined between HRR, VE/VCO2, VE/VO2, BR and the severity of CHF. VO2max, HRR, VE/VO2, VE/VCO2, BR, and AT were the most prominent factors of CPET which showed their validity and reliability in terms of prognosis of CHF. It seems that combination of CPET and other cardiac prognostic tools like echocardiography and measurement of the pressure in cardiac chambers can improve the prognosis in CHF
