The predictive value of heart-type fatty acid-binding protein is independent from symptom duration in normotensive patients with pulmonary embolism.

BACKGROUND

Heart-type fatty acid-binding protein (H-FABP) is a useful biomarker for risk stratification of patients with pulmonary embolism (PE). In patients with acute myocardial infarction, H-FABP plasma concentrations rise after 30 minutes and return to normal within 20-24 hours. We tested whether the predictive value of H-FABP is affected by the duration of symptoms prior to diagnosis in patients with PE.

MATERIAL AND METHODS

We prospectively studied 257 consecutive normotensive patients with confirmed symptomatic PE.

RESULTS

Patients with acute (<24 hours; n=150) symptom onset presented more often with syncope (28.7% vs. 6.5%; p<0.001) compared to patients with symptoms ≥ 24 hours (n=107); other baseline characteristics, comorbidities, and risk factors were distributed equally. Patients with an adverse 30-day outcome (6.6%) had higher H-FABP levels (11.84 [3.57-19.62] ng/ml) compared to patients with a favorable course (3.42 [1.92-5.42] ng/ml; p<0.001). However, the proportion of patients with H-FABP levels ≥ 6 ng/ml did not differ among patients with acute symptom onset and late presentation (p=0.104). Only tachycardia and elevation of H-FABP were associated with an increased risk of an adverse 30-day outcome both in patients with acute symptom onset (H-FABP: OR, 5.8; 95% CI, 1.4-24.5; p=0.016; tachycardia: 7.0 [1.4-36.0]; p=0.018) and late presentation (H-FABP: 9.3 [2.0-43.2]; p=0.004 and tachycardia: 12.3 [1.5-103.6]; p=0.021). The prognostic value could further be improved by the use of a simple H-FABP-based clinical prediction score.

CONCLUSIONS

Our findings indicate that H-FABP is a useful biomarker for risk stratification of normotensive patients with PE regardless of symptom duration prior to diagnosis.