Introduction: The predictive value of brain natriuretic peptide in heart failure is well-known, but its importance as an outcome predictor after a left ventricular assist device ( LVAD ) implantation remains unaddressed. This research aims to examine the significance of brain natriuretic peptide (BNP) as an indicator of treatment outcomes during different post-implantation periods. Methods: A retrospective cohort study included the analysis of medical records of 87 patients in whom LVAD was implanted at the University Clinical Center of Serbia in the period 2014-2020. The correlation of BNP levels with treatment outcomes after operation was evaluated. Results: The average preoperative BNP for all patients was 1244 pg/ mL. The average ejection fraction (EF) was 15% (median), endsystolic diameter (ESD) was 6.80 cm and endiastolic diameter (EDD) was 7.70 cm. Eighty-one patients were NYHA class 4, and 6 patients were NYHA 3. Compared to the preoperative BNP level below or above 1000 pg/mL, there was no significant difference in overall survival of patients after operation (Log Rank [Mantel-Cox] test, p=0.838). BNP levels postoperatively decreased from 358 pg/mL at 3 months upon surgery to 136 pg/mL 5 years upon surgery (Friedman test, p<0.001). BNP levels show strong negative correlation with EF (decrease in BNP level and increase in EF value), and strongly positive correlation with EDD, ESD, and NYHA class (a decrease in BNP and a decrease in EDD, ESD, and NYHA). Conclusion: Preoperative BNP level may not be an adequate predictor of the outcome after LVAD implantation, but the post-implantation decrease in BNP levels is highly correlated with parameters that indicate an improvement in the clinical status and positive changes in the myocardium and long-term survival.