B-TYPE NATRIURETIC PEPTIDE

Chronic heart failure (CHF) is the most frequent cause of hospitalisation for people over 65 and is one of the leading causes of mortality. Heart failure occurs in approximately 1 in 10, becoming more prevalent with advancing age. Congestive heart failure (CHF) occurs when the heart cannot deliver a sufficient supply of blood to the body.

The clinical diagnosis of moderate to severe heart failure is no real challenge for the clinician, but diagnosis of CHF is much more difficult in the early or asymptomatic stages, and relies on non-specific symptoms (e.g. breathlessness) and imaging technology. Measurement of B-Type Natriuretic Peptide (BNP) presents itself as a diagnostic aid, as well as a monitoring tool for therapy.

BNP is a cardiac hormone produced predominantly by the heart ventricles and its release is directly proportional to ventricular volume expansion and pressure overload. It provides a reliable marker for heart failure, with 98% diagnostic accuracy versus other clinical findings in patients with or without disease history. It will help differentiate chronic obstructive pulmonary disease from CHF. Early diagnosis and therapy delays disease progression and improves patients` outcome. BNP can detect both systolic and diastolic dysfunction and correlates closely with The New York Heart Association (NYHA) classification.

The New York Heart Association developed a functional classification system for CHF consisting of four stages based on the severity of the symptoms. BNP can be used as an aid in the diagnosis of all degrees of CHF severity, including asymptomatic patients.

Stage 1: cardiac disease, but ordinary physical activity does not produce undue fatigue or pain
Stage 2: comfortable at rest, but symptomatic during ordinary physical activity
Stage 3: comfortable at rest, but symptomatic upon minimal physical activity
Stage 4: discomfort with ANY physical activity with respiratory distress

Circulating BNP concentrations increase with the severity of CHF based on this classification, and also provide an independent assessment of ventricular function without the use of other invasive or expensive diagnostic tests.

In Summary: Mild heart failure patients can be identified by measuring BNP with very acceptable diagnostic accuracy and this test is helpful in selecting patients who need further cardiological investigation and management, and helps to reduce much more costly echocardiographic screening.