B-type natriuretic peptide predicts cardiac morbidity and mortality after major surgery.
BACKGROUND
The objective of this study was to determine whether measurement of B-type natriuretic peptide (BNP) concentration before operation could be used to predict perioperative cardiac morbidity.


METHODS
A prospective derivation study was performed in high-risk patients undergoing major non-cardiac surgery, with a subsequent validation study. A venous blood sample was taken the day before surgery for measurement of plasma BNP concentration. Screening for cardiac events (non-fatal myocardial infarction and cardiac death) was performed using clinical criteria, cardiac troponin I analysis and serial electrocardiography.


RESULTS
Forty-one patients were recruited to the derivation cohort and 149 to the validation cohort. In the derivation cohort, the median (interquartile range) BNP concentration in the 11 patients who had a postoperative cardiac event was 210 (165-380) pg/ml, compared with 34.5 (14-70) pg/ml in those with no cardiac complications (P < 0.001). In the validation cohort, the median BNP concentration in the 15 patients who had a cardiac event was 351 (127-1034) pg/ml, compared with 30.5 (11-79.5) pg/ml in the remainder (P < 0.001). BNP concentration remained a significant outcome predictor in multivariable analysis (P < 0.001). Using receiver-operator curve analysis it was calculated that a BNP concentration of 108.5 pg/ml best predicted the likelihood of cardiac events, with a sensitivity and specificity of 87 per cent each.


CONCLUSIONS
Preoperative serum BNP concentration predicted postoperative cardiac events in patients undergoing major non-cardiac surgery independently of other risk factors.
Gibson
S C
SC
Department of General and Vascular Surgery, Gartnavel General Hospital, Glasgow, UK. simoncgibson@hotmail.com
Payne
C J
CJ
Byrne
D S
DS
Berry
C
C
Dargie
H J
HJ
Kingsmore
D B
DB
D000368:Aged; D015331:Cohort Studies; D005260:Female; D006331:Heart Diseases / Q000097:blood / Q000401:mortality*; D006801:Humans; D008297:Male; D020097:Natriuretic Peptide, Brain / Q000378:metabolism*; D011183:Postoperative Complications / Q000097:blood / Q000401:mortality*; D011237:Predictive Value of Tests; D011300:Preoperative Care; D011446:Prospective Studies; D019210:Troponin I / Q000097:blood
D019210:Troponin I; D020097:Natriuretic Peptide, Brain