Usefulness Of The Measurement Of The Plasma NT-ProBNP Level For The Prediction Of The Postoperative Cardiac Risk In Elderly Patients / 대한내과학회지

ABSTRACT

BACKGROUND: The prediction of the postoperative cardiac complications is important in the medical management of patients undergoing noncardiac surgery. Several indices have been developed to predict the outcome, but their usefulness has neither been evaluated nor been widely used. The purpose of this study was to assess the NT-proBNP as a prognostic factor for the prediction of the postoperative cardiac risk as compared with the existing cardiac indices in elderly patients undergoing orthopedic surgery. METHODS: From September 2003 to January 2004, we examined 50 patients older than 60 years, who were scheduled to undergo orthopedic surgery. The plasma NT-proBNP concentration, clinical cardiac indices and left ventricular ejection fraction were measured prior to the operation. The postoperative outcomes were followed and predictors for postoperative cardiac risk were identified. RESULTS: Cardiac complications occurred in 22% of the patients. A statistically significant increase in the cardiac complications was observed in the patients with higher plasma concentration of NT-proBNP (p<0.001), higher original cardiac index score (p<0.001), higher revised cardiac index score (p=0.004) and that fell into the major group of the American college of cardiology/American heart association guidelines (p=0.018). The NT-proBNP concentrations were positively correlated with the original cardiac index score (r=0.666, p<0.001), revised cardiac index score (r=0.429, p=0.002) and grouping by the ACC/AHA guidelines (r=0.497, p<0.001). The area under the receiver-operating characteristic curve for the plasma NT-proBNP (0.946, 95% CI) was superior to the other cardiac indices. The optimal cut-off point for the prediction of postoperative cardiac complications occurred at a plasma NT-proBNP, concentration of 539.3 pg/mL and provided a 90.9% sensitivity, 92.3% sensitivity, 79.9% positive predictive value and 97.3% negative predictive value. The independent predictors for postoperative adverse cardiac event were age and Goldman index. CONCLUSION: The plasma NT-proBNP level may be a useful parameter for the prediction of postoperative cardiac complications.