Heart failure can be ongoing (chronic), or your condition may start suddenly (acute). Heart failure signs and symptoms may include: 1  Shortness of breath (dyspnea) when you exert yourself or when you lie down. 2  Fatigue and weakness. 3  Swelling (edema) in your legs, ankles and feet. 4  Rapid or irregular heartbeat. 5  Reduced ability to exercise. 6  Persistent cough or wheezing with white or pink blood-tinged phlegm.