A 2016 prospective cohort study which used the E wave DT and B-type natriuretic peptide (BNP) levels to guide diuretic therapy in outpatient HF patients noted a lower incidence of death (hazard ratio [HR] 0.45, 95% CI: 0.30–0.67, p < 0.0001) and lower incidence of worsening renal function (HR 0.49, 95% CI 0.36–0.67, p < 0.0001) compared to the control group (Table 1) [8]. Here, NPPB is linked to hydrops fetalis.