Prognostic Implications of Preoperative N-Terminal Pro-B-Type Natriuretic Peptide Dynamics in Patients Undergoing Cardiac Surgery

BACKGROUND: High levels of N-terminal prohormone of brain natriuretic peptide (NT-proBNP) reflect poor cardiac status in heart failure patients. OBJECTIVES: This study analyzed the association of preoperative NT-proBNP dynamics with 30-day and 5-year mortality after cardiac surgery. METHODS: A consecutive cohort of 6,938 patients undergoing cardiac surgery was analyzed. The relationship between preoperative NT-proBNP levels and 30-day and 5-year mortality (median follow up time: 4.53 [2.00-5.00] years) adjusted for EuroSCORE II was explored with a Cox proportional hazards model. The dynamics of preoperative NT-proBNP levels were analyzed by comparing the values at diagnosis or assignment to surgery with the values on the day before surgery (n = 4,739). Results were validated in an external cohort from the SWEDEHEART registry (n = 3,117). RESULTS: Median preoperative NT-proBNP concentration was 552 (208-1,591) ng/L. Death within 30 days occurred in 2.1% (149/6,938) of the population. High preoperative NT-proBNP levels were associated with higher 30-day and 5-year mortality. Initial high NT-proBNP at diagnosis, with subsequent decrease in preoperative NT-proBNP below 3,000 ng/L, was associated with more favorable perioperative outcomes after adjustment for EuroSCORE II shorter stays in intensive care unit (OR: 0.60, 95% CI: 0.44-0.82), less use of ultrafiltration (OR: 0.48, 95% CI: 0.33-0.70), or extracorporeal membrane oxygenation (OR: 0.26, 95% CI: 0.12-0.57; all P < 0.001) and lower 30-day mortality (HR: 0.21, 95% CI: 0.07-0.61; P = 0.004). Five-year survival was improved in patients with decreases in preoperative NT-proBNP levels (log-rank: P < 0.001, HR: 0.44, 95% CI: 0.30-0.65). CONCLUSIONS: Reductions in NT-proBNP levels before surgery were associated with lower 30-day and 5-year mortality after cardiac surgery. Patients with high NT-proBNP concentrations may benefit from preoperative optimization to lower NT-proBNP.