Which is a major symptom of heart failure?

Shortness of breath, also known as dyspnea, is a major symptom of heart failure. This occurs due to the heart's inability to pump blood effectively, leading to fluid buildup in the lungs (pulmonary congestion). As the heart's function declines, the lungs struggle to oxygenate the blood, causing patients to experience difficulty breathing, particularly during physical activity or when lying flat.

In heart failure, this symptom can become progressively worse and is often one of the first noticeable signs for patients. It highlights the importance of proper heart function in maintaining respiratory health, as the compromised circulation affects oxygen delivery throughout the body.

While fatigue can also be a symptom of heart failure due to reduced cardiac output and insufficient oxygen delivery to tissues, the specific and defining characteristic of shortness of breath directly relates to the typical complications of fluid overload in this condition. Other symptoms like weight loss can occur in some patients, particularly with chronic heart failure or in cases of cachexia, but are not as universally defining as shortness of breath. A persistent cough may also be present due to fluid in the lungs but is not a primary symptom attributed to heart failure in the same way that dyspnea is.