Which symptom, when combined with shortness of breath, suggests congestive heart failure?

Bilateral leg swelling is a critical symptom when combined with shortness of breath that suggests congestive heart failure (CHF). CHF occurs when the heart cannot pump blood effectively, leading to fluid buildup in the lungs and peripheral tissues. This fluid overload can result in swelling in both legs due to the increased pressure in the venous system, which is indicative of heart failure.

When patients present with both shortness of breath and bilateral leg swelling, it raises the suspicion of fluid retention due to the heart's inability to manage blood volume effectively. This is a hallmark of heart failure, as the heart's compromised function prevents proper circulation and leads to an onset of symptoms like dyspnea and edema.

The other symptoms listed—unilateral leg swelling, hemoptysis, and wheezing—do not have the same direct association with congestive heart failure. Unilateral leg swelling can indicate other conditions like deep vein thrombosis, hemoptysis often points to pulmonary or vascular issues, and wheezing can be related to conditions like asthma or COPD. While these symptoms may occur in various cardiopulmonary conditions, bilateral leg swelling in conjunction with shortness of breath is a more classic presentation of congestive heart failure.