Abstract 3218: Serum Brain Natriuretic Peptide Predicts Adverse Clinical Events in Adults with Eisenmenger’s Syndrome
Background: BNP is an important prognostic marker in patients with congestive heart failure (CHF). BNP is elevated in patients with Eisenmenger’s syndrome (ES). The clinical significance of BNP in ES patients is unclear.
Hypothesis: Elevated serum BNP is a predictor of adverse clinical events in patients with ES.
Methods: Adult outpatients with various uncorrected congenital heart defects resulting in ES were retrospectively identified at the Ahmanson/UCLA Adult Congenital Heart Disease Center. BNP, six-minute walk distance (6MWD), and cardiopulmonary exercise echocardiography (CPX) were performed. Patients were subsequently followed for occurrence of adverse clinical events. The primary endpoint was CHF admission or death. The secondary endpoints were occurrence of supraventricular (SVT) or ventricular (VT) arrhythmia.
Results: Twenty patients (mean age 43, +/− 9 yrs) were included. Congenital defects included: VSD (n=13), Truncus Arteriosus (n=2), ASD (n=2), total anomalous pulmonary venous return (n=1), and single ventricle (n=2). Tests performed included: Serum BNP (n=18), 6MWD (n=14), and CPX (n=13). Mean BNP level was 352 pg/ml (+/− 408), 6 MWD was 253 meters (+/− 126), and maximum oxygen consumption (VO2max) was 11.8 ml/kg/min (+/− 3.8). Seven patients (35 %) met the primary endpoint (CHF=4, death=4) a mean of 31 days (range 5–95) after serum BNP determination. Cause of death was sepsis in 1 patient and presumed arrhythmia in 3 patients (all with VSD). Mean BNP in patients meeting the primary endpoint was 664 pg/ml (+/− 362) versus 154 pg/ml (+/− 303) in patients without CHF or death (p=0.009). A BNP cut-off of 250 pg/ml had 100 % sensitivity, 91% specificity, 87.5% PPV, and 100% NPV for predicting the primary outcome. SVT occurred in 10 patients (50%) and VT (on telemetry monitoring) occurred in 3 patients (15%). BNP was not predictive of SVT or VT. BNP correlated inversely with VO2max (r= −0.714, p=0.014) and 6MWD (r= −0.65, p=0.022). BNP did not correlate with visually estimated right or left ventricular ejection fractions (EF). EF was not predictive of death/CHF admission, SVT, or VT.
Conclusions: Elevated serum BNP is predictive of CHF admission or death in patients with ES. BNP levels are inversely correlated with VO2max and 6MWD.