Abstract 831: Heart-Type Fatty Acid-Binding Protein Predicts Outcome In Normotensive Patients With Pulmonary Embolism
The identification of normotensive patients with pulmonary embolism (PE) who may be at increased risk for death or major complications remains challenging. We and others recently reported that Heart-type Fatty Acid-Binding Protein (H-FABP) is a useful novel biomarker for risk stratification of patients with PE. However, these studies included both hemodynamically unstable and normotensive patients. We now compared the predictive value of H-FABP with that of cardiac troponin T (cTnT) and NT-proBNP in 127 consecutive patients with acute PE who were normotensive on admission. H-FABP ranged from 0.4 to 86.1 ng/mL (mean, 5.5±9.4), cTnT from 0.005 to 0.6 ng/mL (0.05±0.1), and NT-proBNP from 10 to 67,631 pg/mL (3,151±7,248). H-FABP values were above the cut-off value of 6 ng/mL in 28 patients. Three of them suffered major complications within the first 30 days and 7 died during 6-month follow-up. In contrast, only 1 of 99 patients with normal H-FABP values suffered complications (P=0.033 vs. patients with elevated H-FABP), and 6 died within 6 months (P=0.008). Normal H-FABP on admission reliably predicted an uncomplicated 30-day course (NPV, 0.99; 95% CI, 0.95–0.99) and 6-month survival (NPV, 0.94; 95% CI, 0.87–0.98). Conversely, the relative risk for in-hospital complications was 10.6 (95% CI, 1.15–98.10), and for death at 6-month follow-up 4.13 (95% CI, 1.51–11.29) if H-FABP was elevated on admission. In accordance with these data, the probability of 6-month survival according to Kaplan-Meier analysis was significantly higher in patients with normal compared to elevated H-FABP on admission (P=0.0019 by the log-rank test). The combination with echocardiographic findings did not add further prognostic information compared to H-FABP alone. In contrast to H-FABP, the occurrence of complications or death was not significantly different in normotensive patients with normal (n=91) vs. elevated (>0.04 ng/mL) cTnT (n=36; P=0.32 and 0.35 for complications and death, respectively), and those with low (n=63) vs. elevated (>1000 pg/mL) NT-proBNP (n=64; P=0.62 and 1.0, respectively). In conclusion, H-FABP may prove useful for identification of normotensive patients with PE and an increased risk for complications, who might benefit from early aggressive therapy.