NT-proBNP in the mitral valve surgery.

Background: Prognosis and severity of mitral valve disease in patients are reflected in their natriuretic peptide levels. Patients in the upper margin of this range with severe mitral valve dysfunction also present with a range of myocardial dysfunction and symptomatic progression. We investigated whether serial pre- and immediate postoperative measurements of N-terminal probrain natriuretic peptide (NT-proBNP) can serve as surrogate markers of these surgical patients' severity status and predictors of their immediate postoperative progress.

Methods: Clinical characteristics, echocardiographic indices, and preoperative and postoperative day 1, 5, 7 values of NT-proBNP were retrospectively recorded in a cohort of 75 patients who underwent mitral valve surgery. They were analyzed as a whole and separately for those suffering from severe mitral regurgitation. Correlations, multiple linear regression, logistic regression, and nonparametric receiver operating characteristic curve analyses were implemented.

Results: The patients' preoperative New York Heart Association class, presence of atrial fibrillation, and left ventricular function were strongly correlated with the preoperative NT-proBNP level. Specifically for those with severe mitral regurgitation, preoperative NT-proBNP was also correlated to their left ventricular end-diastolic diameter. NT-proBNP values increased respectively postoperatively in all patients and were related to the preoperative values, the patients' preoperative characteristics, and the operative times. Logistic regression analysis identified preoperative NT-proBNP as a predictor of postoperative optimal clinical outcome (P < 0.001).

Conclusions: NT-proBNP is a valuable biomarker of the clinical presentation and immediate postoperative outcome in patients undergoing mitral valve surgery. The preoperative measurement of NT-proBNP can be used to predict an optimal postoperative clinical outcome.