NPPB and hydrops fetalis: Observational studies by Ribeiro et al. (2014) [25], Koskinas et al. (2015) [26], Seoudy et al. (2019) [27], and Kaneko et al. (2019) [28] indicate that elevated pre-TAVR levels of NT-proBNP and BNP are associated with a worse 2-year prognosis in terms of overall survival and HF admission.