Diagnosis of Right Ventricular Dysfunction in Acute Pulmonary Embolism with N-terminal Probrain Natriuretic Peptide (NT-proBNP)

Lee, Young Ju

Abstract

BACKGROUND
Patients with pulmonary embolism are at high risk of death because of right ventricular dysfunction (RVD) and mortality rate increases with worsening right ventricular dysfuction. The utility of N-terminal probrain natriuretic peptide (NT-proBNP) testing in the emergency department for diagnosing right ventricular dysfunction with pulmonary embolism and optimal cut-off points for its uses are not well established.
METHODS
Forty-nine consecutive patients with confirmed pulmonary embolism, who visited our emergency medical center from March 2005 to September 2006, were recruited. Patients with congestive heart failure and chronic renal failure were excluded from study enrollment. The diagnosis of right ventricular dysfunction was based on echocardiographic evidence of right ventricular dysfunction.
RESULTS
The mean age was 68+/-11 yr, and 71% of the patients were women. The median NT-proBNP level among 29 patients (59%) who had RVD was 1296 versus 250 pg/ml for those 20 patients (41%) who did not have RVD (p=0.01). The area under the receiver operating characteristic curve was 0.94 (95% CI of 0.89~0.98). At a cutoff of 400 pg/ml, NT-proBNP had a sensitivity of 97%, a specificity of 75%, and an overall accuracy of 88% for RVD (p=0.01). An NT-proBNP level <400 pg/ml was optimal for ruling out RVD, which was a negative predictive value of 94%. Increased NT- proBNP was the strong independent predictor of RVD (odds ratio 13, 95% CI 4.3-39.0, p=0.01).
CONCLUSIONS
NT-proBNP levels are frequently increased in patients with pulmonary embolism who have RVD than who did not have RVD. In acute pulmonary embolism, NT-proBNP elevation is highly predictive of RVD.