Which sign is a component of Beck's Triad?

• A. Hyperkalemia
• B. Muffled heart tones
• C. Cough
• D. Headache

Answer: (B)

Beck's Triad points to cardiac tamponade, where fluid around the heart restricts filling during diastole. This causes a drop in stroke volume and blood pressure (hypotension), backup of blood in the veins leading to distended neck veins, and muffled heart sounds because the surrounding fluid dampens the noises from the heart. The sign described here, muffled heart tones, fits this triad best because it reflects the physical effect of the pericardial effusion on auscultation. Hyperkalemia is an electrolyte issue that can affect rhythm, not a hallmark of tamponade. Cough and headache are nonspecific symptoms and do not indicate the muffled heart sounds caused by pericardial fluid. In practice, not all patients show all three signs, but muffled heart sounds are a classic clue to tamponade physiology.