In the non-heart-failure group (n = 25), the postoperative change in NTproBNP was also significant (p < 0.001), both between preoperative values and 24 h post-surgery (p = 0.001) and between preoperative values and 48 h post-surgery (p = 0.007), with no statistical significance in the dynamic changes between the first and second postoperative days. Here, NPPB is linked to heart failure.