The prognostic value of pre-operative and post-operative B-type natriuretic peptides in patients undergoing noncardiac surgery: B-type natriuretic peptide and N-terminal fragment of pro-B-type natriuretic peptide: a systematic review and individual patient data meta-analysis.

OBJECTIVES: The objective of this study was to determine whether measuring post-operative B-type natriuretic peptides (NPs) (i.e., B-type natriuretic peptide [BNP] and N-terminal fragment of proBNP [NT-proBNP]) enhances risk stratification in adult patients undergoing noncardiac surgery, in whom a pre-operative NP has been measured. BACKGROUND: Pre-operative NP concentrations are powerful independent predictors of perioperative cardiovascular complications, but recent studies have reported that elevated post-operative NP concentrations are independently associated with these complications. It is not clear whether there is value in measuring post-operative NP when a pre-operative measurement has been done. METHODS: We conducted a systematic review and individual patient data meta-analysis to determine whether the addition of post-operative NP levels enhanced the prediction of the composite of death and nonfatal myocardial infarction at 30 and ≥180 days after surgery. RESULTS: Eighteen eligible studies provided individual patient data (n = 2,179). Adding post-operative NP to a risk prediction model containing pre-operative NP improved model fit and risk classification at both 30 days (corrected quasi-likelihood under the independence model criterion: 1,280 to 1,204; net reclassification index: 20%; p < 0.001) and ≥180 days (corrected quasi-likelihood under the independence model criterion: 1,320 to 1,300; net reclassification index: 11%; p = 0.003). Elevated post-operative NP was the strongest independent predictor of the primary outcome at 30 days (odds ratio: 3.7; 95% confidence interval: 2.2 to 6.2; p < 0.001) and ≥180 days (odds ratio: 2.2; 95% confidence interval: 1.9 to 2.7; p < 0.001) after surgery. CONCLUSIONS: Additional post-operative NP measurement enhanced risk stratification for the composite outcomes of death or nonfatal myocardial infarction at 30 days and ≥180 days after noncardiac surgery compared with a pre-operative NP measurement alone.

Postoperative B-type natriuretic peptide for prediction of major cardiac events in patients undergoing noncardiac surgery: systematic review and individual patient meta-analysis.

BACKGROUND: It is unclear whether postoperative B-type natriuretic peptides (i.e., BNP and N-terminal proBNP) can predict cardiovascular complications in noncardiac surgery. METHODS: The authors undertook a systematic review and individual patient data meta-analysis to determine whether postoperative BNPs predict postoperative cardiovascular complications at 30 and 180 days or more. RESULTS: The authors identified 18 eligible studies (n = 2,051). For the primary outcome of 30-day mortality or nonfatal myocardial infarction, BNP of 245 pg/ml had an area under the curve of 0.71 (95% CI, 0.64-0.78), and N-terminal proBNP of 718 pg/ml had an area under the curve of 0.80 (95% CI, 0.77-0.84). These thresholds independently predicted 30-day mortality or nonfatal myocardial infarction (adjusted odds ratio [AOR] 4.5; 95% CI, 2.74-7.4; P < 0.001), mortality (AOR, 4.2; 95% CI, 2.29-7.69; P < 0.001), cardiac mortality (AOR, 9.4; 95% CI, 0.32-254.34; P < 0.001), and cardiac failure (AOR, 18.5; 95% CI, 4.55-75.29; P < 0.001). For greater than or equal to 180-day outcomes, natriuretic peptides independently predicted mortality or nonfatal myocardial infarction (AOR, 3.3; 95% CI, 2.58-4.3; P < 0.001), mortality (AOR, 2.2; 95% CI, 1.67-86; P < 0.001), cardiac mortality (AOR, 2.1; 95% CI, 0.05-1,385.17; P < 0.001), and cardiac failure (AOR, 3.5; 95% CI, 1.0-9.34; P = 0.022). Patients with BNP values of 0-250, greater than 250-400, and greater than 400 pg/ml suffered the primary outcome at a rate of 6.6, 15.7, and 29.5%, respectively. Patients with N-terminal proBNP values of 0-300, greater than 300-900, and greater than 900 pg/ml suffered the primary outcome at a rate of 1.8, 8.7, and 27%, respectively. CONCLUSIONS: Increased postoperative BNPs are independently associated with adverse cardiac events after noncardiac surgery.

The predictive ability of pre-operative B-type natriuretic peptide in vascular patients for major adverse cardiac events: an individual patient data meta-analysis.

OBJECTIVES: The aims of this study were to perform an individual patient data meta-analysis of studies using B-type natriuretic peptides (BNPs) to predict the primary composite endpoint of cardiac death and nonfatal myocardial infarction (MI) within 30 days of vascular surgery and to determine: 1) the cut points for a natriuretic peptide (NP) diagnostic, optimal, and screening test; and 2) if pre-operative NPs improve the predictive accuracy of the revised cardiac risk index (RCRI). BACKGROUND: NPs are independent predictors of cardiovascular events in noncardiac and vascular surgery. Their addition to clinical risk indexes may improve pre-operative risk stratification. METHODS: Studies reporting the association of pre-operative NP concentrations and the primary study endpoint, post-operative major adverse cardiovascular events (defined as cardiovascular death and nonfatal MI) in vascular surgery, were identified by electronic database search. Secondary study endpoints included all-cause mortality, cardiac death, and nonfatal MI. RESULTS: Six data sets were obtained, 5 for BNP (n = 632) and 1 for N-terminal pro-BNP (n = 218). An NP level higher than the optimal cut point was an independent predictor for the primary composite endpoint (odds ratio: 7.9; 95% confidence interval: 4.7 to 13.3). BNP cut points were 30 pg/ml for screening (95% sensitivity, 44% specificity), 116 pg/ml for optimal (highest accuracy point; 66% sensitivity, 82% specificity), and 372 pg/ml for diagnostic (32% sensitivity, 95% specificity). Subsequent to revised cardiac risk index stratification, reclassification using the optimal cut point significantly improved risk prediction in all groups (net reclassification improvement 58%, p < 0.000001), particularly in the intermediate-risk group (net reclassification improvement 84%, p < 0.001). CONCLUSIONS: Pre-operative NP levels can be used to independently predict cardiovascular events in the first 30 days after vascular surgery and to significantly improve the predictive performance of the revised cardiac risk index.