In a patient with heart failure, what is a common symptom that may indicate worsening fluid overload?

Shortness of breath is a classic symptom indicating worsening fluid overload in patients with heart failure. This occurs due to congestion in the lungs caused by excess fluid accumulation, often leading to pulmonary edema. As the heart becomes less effective at pumping blood, fluid can back up in the pulmonary circulation, resulting in difficulties with breathing, especially during physical activities or while lying down.

In contrast, increased energy levels, weight loss, and improved exercise tolerance would not be expected in the context of worsening heart failure; instead, they would suggest stability or improvement in the patient's condition. These symptoms reflect a more favorable state of health, whereas shortness of breath directly correlates with the adverse effects of fluid retention and decreased cardiac output. This makes shortness of breath a key indicator for healthcare providers to assess the patient's status and determine the need for intervention.