Brain natriuretic peptide is a reliable indicator of ventilatory abnormalities during cardiopulmonary exercise test in heart failure patients.

Background: Whether brain natriuretic peptide (BNP), a neurohormone marker of ventricular dysfunction, correlates with an enhanced ventilatory response (EVR) during cardiopulmonary exercise test, a well-known predictor of prognosis, in systolic heart failure (HF) is currently unknown. Material/Methods: Resting BNP was measured in 134 consecutive stable outpatients aged 69±11 years with mild to moderate HF and LV ejection fraction (LVEF) <40% who performed a maximal exercise test. EVR was assessed as the slope of the relation between minute ventilation and carbon dioxide production (VE/VCO 2 slope) ≥35. Results: LVEF averaged 33±7%, BNP 350±396 pg/ml, and the VE/VCO 2 slope 36±8. Fifty-six of 123 patients (45%) had EVR. BNP correlated with VE/VCO 2 slope (r=0.453; p<0.01). By multivariate logistic regression, plasma BNP was the only independent predictor of EVR (RR 1.004 per unit increment, 95%CI: 1.002-1.006, p<0.0001). A BNP ≥160 pg/ml had 86% sensitivity, 67% specificity, and 76% overall accuracy for the prediction of EVR (chi square: 37.4, RR 12.2, 95% CI: 4.96-30.3, p<0.0001, AUC 0.815 (95%CI: 0.738-0.892)). Conclusions: In systolic HF, plasma BNP is related to an enhanced ventilatory response to exercise and offers a simple and reliable alternative to the cardiopulmonary exercise test in patients with inability or contraindications to exercise.