Which symptom is a key sign of heart failure?

Dyspnea, or shortness of breath, is a key symptom of heart failure due to the heart's inability to effectively pump blood, which can lead to fluid buildup in the lungs. This fluid accumulation occurs because when the heart is compromised, it fails to manage the blood flow efficiently, resulting in increased pressure in the pulmonary circulation. This pressure causes fluid to leak into the lung tissue, leading to difficulty breathing, especially during physical activity or while lying flat.

While chest pain can occur in heart failure, it is not as definitive as dyspnea in identifying the condition. Severe fatigue can be a symptom as well, but it is more generalized and can be associated with many other conditions. Fever is not typically a direct symptom of heart failure, although it could occur in cases where an underlying infection or another acute issue is present. Thus, dyspnea serves as a hallmark symptom of heart failure, often prompting further evaluation and management of the condition.