What is a common sign of left heart failure?

Crackles in the lungs, also known as "rales," are a common sign of left heart failure. This occurs because the left side of the heart is unable to effectively pump blood out to the body, leading to a backlog of blood in the pulmonary circulation. This congestion causes fluid to leak into the alveoli (air sacs) in the lungs, resulting in the characteristic crackling sounds when air passes through these fluid-filled areas during breathing.

In left heart failure, patients often experience symptoms related to pulmonary congestion, including difficulty breathing, especially during exertion or when lying flat, which can also lead to orthopnea. While jugular venous distention and peripheral edema are associated with right heart failure, they are less indicative of left heart failure specifically. Thus, the presence of crackles in the lungs serves as a direct reflection of the pulmonary congestion indicative of left heart failure.