B-type natriuretic peptide and C-terminal-pro-endothelin-1 for the prediction of severely impaired peak oxygen consumption

OBJECTIVE

To assess the utility of B-type natriuretic peptide (BNP) and C-terminal-pro-endothelin-1 (CT-proET-1) to predict a severely impaired peak oxygen consumption (peak VO(2), < 14 mL kg(-1) min(-1)) in patients referred for cardiopulmonary exercise testing.

DESIGN

Cross-sectional study.

SETTING

Tertiary care center.

METHODS

Peak VO(2), BNP and CT-proET-1 were assessed in 141 consecutive patients referred for cardiopulmonary exercise testing.

RESULTS

B-type natriuretic peptide [median (interquartile range) 48 (38-319) vs. 33 (15-86) pg mL(-1); P = 0.002] and CT-proET-1 [87 (76-95) vs. 60 (52-74) pmol L(-1); P < 0.001] were higher in patients with a peak VO(2) < 14 mL kg(-1) min(-1) (n = 30) than in those with a peak VO(2) > or = 14 mL kg(-1) min(-1) (n = 111). CT-pro-ET-1 had a higher area under the receiver-operator-characteristics curve (AUC) to predict a peak VO(2) < 14 mL kg(-1) min(-1) than BNP (0.79 vs. 0.68; P = 0.04). The optimal BNP cut-off of 37.2 pg mL(-1) had a sensitivity of 80% and a specificity of 56%. The optimal CT-proET-1 cut-off of 74.4 pmol L(-1) had a sensitivity of 80% and specificity of 76%. A five-item score composed of body mass index, diabetes, forced expiratory volume within the first second, alveolo-arterial oxygen pressure difference, and BNP had an AUC of 0.88 to predict a peak VO(2) < 14 mL kg(-1) min(-1). Adding CT-proET-1 to the score resulted in an AUC of 0.92.

CONCLUSIONS

C-terminal-pro-endothelin-1 is superior to BNP for the prediction of a peak VO(2) < 14 mL kg(-1) min(-1) in patients referred for CPET. A score incorporating body mass index, diabetes status, spirometry, blood gases, BNP and CT-proET-1 improves the prediction of a peak VO(2) < 14 mL kg(-1) min(-1) based on single biomarkers.

Long-term prognostic value of B-type natriuretic peptide in cardiac and non-cardiac causes of acute dyspnoea

BACKGROUND

B-type natriuretic peptide (BNP) levels significantly predict increased risk of death in heart failure. The predictive role of BNP levels in patients with non-cardiac causes of acute dyspnoea presenting to the emergency department is not well characterized.

MATERIALS AND METHODS

The B-type natriuretic peptide for Acute Shortness of Breath EvaLuation (BASEL) study enrolled consecutive patients with acute dyspnoea.

RESULTS

Cumulative mortality was 14.8%, 33.1% and 51.9% in 452 patients (age: 19-97 years; 58% male) within low (< 100 pg mL(-1)), intermediate (100-500 pg mL(-1)) and high (> 500 pg mL(-1)) BNP plasma levels at 18 months of follow-up. BNP classes (point estimate: 1.55, 95%CI: 1.19-2.03, P = 0.001) in addition to age, increased heart rate and diuretic use emerged as significant predictors for long-term mortality in multivariable Cox regression analyses. The BNP concentration alone had an area under the receiver operating characteristic curve of 0.71 (95%CI: 0.66-0.76; P < 0.001) for predicting 18 months mortality. BNP plasma levels independently predicted long-term risk of death in patients with non-cardiac (point estimate: 1.72, 95%CI: 1.16-2.56; P = 0.007) and with cardiac causes of acute dyspnoea (point estimate: 2.21, 95%CI: 1.34-3.64; P = 0.002).

CONCLUSIONS

BNP levels are strong and independent predictors for long-term mortality in unselected dyspnoeic patients presenting to the emergency department independent from the cause of dyspnoea.

Decortication in chronic pleural empyema. Investigation of lung function based on perfusion scintigraphy

The study presents measurements in spirometry and scintigraphic lung perfusion, before and after decortication, in 9 patients treated for chronic pleural empyema with special emphasis on measuring changes by perfusion scintigraphy. Preoperatively, the average vital capacity (VC) was 60% and the average FEV1 was 65% of the predicted. Perfusion of the affected side showed an average reduction to 22%. After decortication all functional data showed an improvement (average VC 78.5%, average FEV1 79.5%) the percentage of lung perfusion having increased to a mean of 37.8%.