Immediately postoperative B-type natriuretic peptide and its predictive value

Major vascular surgery involves a high risk of major cardiovascular morbidity and mortality. A method of predicting perioperative myocardial events is required. Preoperative B-type natriuretic peptide (BNP) has been evaluated for this purpose. The aims of this study were to determine the postoperative course of BNP levels and correlate these levels with the outcome.

The present study included 45 patients undergoing major vascular surgery. These patients further underwent serial venous blood sampling for troponin-T and BNP and serial electrocardiograms, pre- and postoperatively (immediately postoperatively and at days 1 through 4).

Of the 45 patients, seven suffered myocardial damage, as defined by troponin-T. An immediate postoperative BNP (cutoff, 171 pg/mL) was better able to predict cardiac damage (p = 0.027) than BNP levels preoperatively (cutoff, 281 pg/mL, p = 0.042) and on day 1 postoperatively (cutoff, 182 pg/mL, p = 0.032). Only the preoperative BNP levels showed an effect on survival. Patients with a preoperative BNP >281 pg/mL had a mean survival of 12.7 months, as compared with 17.6 months for patients with a BNP <281 pg/mL, p = 0.044.

Preoperative BNP is an accurate determinant of postoperative cardiac morbidity and all cause survival, with BNP in the immediate postoperative period being an even more accurate predictor of cardiac events. An immediate postoperative BNP might help risk stratify patients for the next 72 hours in the perioperative period (and maybe longer).