Wallach's Interpretation of Diagnostic Tests: Pathways to Arriving at a Clinical Diagnosis (755 page)

   Reading >130 pg/mL = 19% chance of sudden death.

   Reading <130 pg/mL = 1% chance of sudden death.

   Differential diagnosis of dyspnea: Readings <100 pg/mL rule out CHF as cause of dyspnea, and readings >400 pg/mL indicate a 95% likelihood of CHF. Readings between 100 and 400 pg/mL warrant further workup.

   Determination of severity of CHF: Higher values correlate with increasing New York Heart Association classes I–IV. BNP is a prognostic tool for classes III and IV.

   Diagnosis of left ventricular dysfunction: Routine testing is not recommended for screening asymptomatic patient populations for left ventricular dysfunction. Increase in BNP in right heart failure is less than in left ventricular dysfunction.

   At appropriate cutoff values, BNP and NT-proBNP have similar S/S = 70%/70% and NPV = 80%.

   Greater increases predict worse adverse outcomes in patients with CHF.

   Increased values after acute myocardial infarction predict poorer prognosis.

   BNP increases with arrhythmias that are less marked.

   BNP and NT-proBNP can be increased in renal failure, especially if dialysis is needed.

   Abnormal echocardiogram without symptoms: mean value = 300 pg/mL.

   Interpretation

Increased In

   Heart failure