If elevated, which laboratory test would support a diagnosis of congestive heart failure?

If elevated, which laboratory test would support a diagnosis of congestive heart failure?

• A. Homocysteine
• B. Troponin
• C. Albumin cobalt binding
• D. B-type natriuretic peptide

Answer: (D)

Ventricular stretch from volume or pressure overload in congestive heart failure stimulates the heart to release B-type natriuretic peptide (BNP). An elevated BNP level reflects this increased wall tension and volume overload, so it supports a diagnosis of heart failure and helps distinguish cardiac from non-cardiac causes of dyspnea. BNP (and its related NT-proBNP) also correlates with the severity and prognosis of heart failure, making it the most relevant lab test for this question. Homocysteine is a vascular risk marker and not specific for heart failure. Troponin indicates myocardial injury, such as from infarction, and while it can be elevated in some heart failure patients, it does not specifically diagnose CHF. Albumin cobalt binding relates to ischemia-modified albumin and is not used to diagnose heart failure.

Ventricular stretch from volume or pressure overload in congestive heart failure stimulates the heart to release B-type natriuretic peptide (BNP). An elevated BNP level reflects this increased wall tension and volume overload, so it supports a diagnosis of heart failure and helps distinguish cardiac from non-cardiac causes of dyspnea. BNP (and its related NT-proBNP) also correlates with the severity and prognosis of heart failure, making it the most relevant lab test for this question.

Homocysteine is a vascular risk marker and not specific for heart failure. Troponin indicates myocardial injury, such as from infarction, and while it can be elevated in some heart failure patients, it does not specifically diagnose CHF. Albumin cobalt binding relates to ischemia-modified albumin and is not used to diagnose heart failure.