One hundred and ninety consecutive patients discharged with congestive heart failure were examined with clinical evaluation, blood chemistry, 24 h Holter monitoring, exercise test and radionuclide angiography. Median left ventricular ejection fraction was 0.30, 46% were in New York Heart Association class II and 44% in III. Total mortality after 1 year was 21%, after 2 years 32%. Of 60 deaths, 33% were sudden and 49% due to pump failure. Multivariate analyses identified totally different risk factors for sudden death: ventricular tachycardia, s-sodium≤137 mmol/l, s-magnesium≤0.80 mmol/l, s-creatinine>121 μmol/l, and maximal change in heart rate during exercise≤35 min - 1 , and for death from progressive pump failure: New York Heart Association class III+IV, Δheart rate over 24 h≤50 min - 1 , low ejection fraction, high resting p-noradrenaline, s-urea>7.6 mmol/l, s-potassium<3,5 mmol/l, and maximal exercise duration≤4 min. In conclusion, this study demonstrated different risk factors for sudden death and for death from progressive pump failure.