Symptoms of congestive heart failure : Fatigue, breathlessness, swelling of feet and abdomen due to excess fluid. Fatigue is due to low cardiac output, while breathlessness is due to pulmonary congestion. Generalized fluid retention can cause anasarca, a condition in which all the serous cavities of the body are filled with fluid. Urine output also comes down in congestive heart failure due to deceased renal perfusion. This further adds on to the fluid retention.