Which lab result confirms heart failure?

Which lab result confirms heart failure?

• A. K+ 5.6
• B. BNP 820
• C. BUN 9
• D. Troponin <0.02

Answer: (B)

The main idea is that BNP rises when the heart muscle is stretched from volume overload, which happens in heart failure. A BNP level of 820 is markedly elevated, which strongly supports a diagnosis of heart failure and correlates with the presence of ventricular strain and fluid overload. The other labs don’t confirm heart failure on their own. A potassium of 5.6 can occur for reasons unrelated to HF and doesn’t diagnose it. A BUN of 9 is normal-ish and renal function alone doesn’t establish HF. A troponin level below 0.02 suggests no acute myocardial injury, which helps rule out a heart attack but doesn’t confirm heart failure by itself. So the elevated BNP is the best lab finding to confirm heart failure.

The main idea is that BNP rises when the heart muscle is stretched from volume overload, which happens in heart failure. A BNP level of 820 is markedly elevated, which strongly supports a diagnosis of heart failure and correlates with the presence of ventricular strain and fluid overload.

The other labs don’t confirm heart failure on their own. A potassium of 5.6 can occur for reasons unrelated to HF and doesn’t diagnose it. A BUN of 9 is normal-ish and renal function alone doesn’t establish HF. A troponin level below 0.02 suggests no acute myocardial injury, which helps rule out a heart attack but doesn’t confirm heart failure by itself. So the elevated BNP is the best lab finding to confirm heart failure.