The following conditions may cause symptoms similar to those of heart failure.

Other conditions that may cause shortness of breath include:

• Lung diseases (emphysema, asthma, or a blood clot in the lung) or lower respiratory infections (pneumonia).
• Low levels of the oxygen-carrying component in red blood cells in the blood (anemia).
• Anxiety or panic attacks.
• Hyperventilation.
• Poor physical conditioning.

Other conditions that can cause fluid buildup (edema), especially in the legs and feet, include:

• Insufficient return of blood to the heart from the legs (venous insufficiency).
• Kidney disorders or kidney failure.
• A blood clot in the deep leg veins.
• Low protein levels in the blood vessels system, which lead to leakage of fluid from blood into the body tissues (hypoalbuminemia).
• Overactive thyroid gland (hyperthyroidism).
• Liver disease.
• Inflammation of the heart or the sac (pericardium) around the heart (pericarditis), which may be associated with rheumatic fever.
• Use of steroids (corticosteroids, such as prednisone or cortisone).
• Excessive salt intake.
• In women, accumulation of fluid in the lower legs, especially during hot weather. This often has no clear cause and usually does not indicate a problem.

The individual symptoms of heart failure (such as fluid accumulation in the tissues, difficulty breathing, abdominal swelling or pain, and fatigue) can have many other causes that are not listed here.