Failure of the left side of the heart (left-sided failure) is most common. It leads to increased pressure in the pulmonary veins in the lungs, which forces fluid into the surrounding microscopic air sacs (alveoli) that transfer oxygen to the bloodstream. As the alveoli fill with fluid, they no longer work properly, which limits the amount of oxygen available to the body and produces the most characteristic symptoms of congestive heart failure: fatigue and shortness of breath. In right-sided failure, the increased pressure in the veins returning blood from the rest of the body combined with the compensatory retention of sodium and water leads to fluid accumulation and swelling in the abdomen, liver and legs. Often, both left-and right-sided heart failure occur together.
CHF symptoms include:
Shortness of breath and wheezing after limited physical exertion. In advanced cases shortness of breath occurs even at rest, and attacks of severe breathlessness disturb sleep (left-sided failure). Severe fatigue and weakness. Dry cough or cough that produces frothy or bloody sputum (left-sided failure). Frequent urination during the night (right-sided failure). Swelling of the ankles and feet, or swelling in the lower back if the patient is bedridden (right-sided failure). Rapid weight gain due to fluid retention (right-sided failure). Abdominal pain and a feeling of fullness (right-sided failure). Swollen neck veins (right-sided failure). Loss of appetite (anorexia); nausea and/or vomiting. Irregular or rapid heartbeat. Anxiety; in severe cases irritability, restlessness, and mental confusion may occur.