Preoperative plasma N-terminal pro-brain natriuretic peptide as a marker of cardiac risk in patients undergoing elective non-cardiac surgery.

Abstract

Plasma N-terminal pro-brain natriuretic peptide (NTproBNP) is a sensitive marker for heart failure. This study tested whether the preoperative plasma level of NTproBNP could predict cardiac complications in patients undergoing non-cardiac surgery. A total of 190 consecutive patients who underwent elective non-cardiac surgery that required general anaesthesia were studied. In addition to routine preoperative evaluation, a blood sample was taken for estimation of plasma NTproBNP concentration. Postoperative cardiac complications were defined as cardiac death, acute coronary syndrome, heart failure and haemodynamic compromise from cardiac arrhythmias. Fifteen of the 190 patients had a cardiac complication: four had acute coronary syndrome and 13 had congestive heart failure. NTproBNP concentration was significantly higher in patients with a cardiac complication; a level greater than 450 ng/l was predictive of cardiac complications with a sensitivity of 100 per cent and a specificity of 82.9 per cent. Other factors associated with cardiac complications were a higher American Society of Anesthesiologists grade, age and clinical cardiac impairment, but in a multivariate analysis NTproBNP level was the only independent factor. Preoperative plasma NTproBNP concentration may be an independent predictor of cardiac complications in patients undergoing non-cardiac surgery.