Soluble Neprilysin Not Linked to Prognosis in Pulmonary Hypertension

Among individuals with pulmonary hypertension, no associations have been found between circulating soluble neprilysin and prognosis, natriuretic peptide, or right heart catheterization parameters, according to study results recently published in ESC Heart Failure.

This prospective observational study included 79 individuals with pulmonary hypertension whose pulmonary arterial pressure was ≥25 mm Hg and whose pulmonary artery wedge pressure was ≤15 mm Hg.

Right heart catheterization was used to determine these values. The study sample’s mean pulmonary arterial pressure was 42.9±14.5 mm Hg. Associations were investigated between levels of soluble neprilysin and parameters of natriuretic peptide, right heart catheter, or echocardiography. Participants were followed for incidence of all-cause mortality.

To compare categorical variables, the chi-squared test was used. The Student’s t-test was used to compare parametric variables whereas the Mann–Whitney U test was used for nonparametric variables.

Soluble neprilysin was not correlated with B-type natriuretic peptide (P =.86), high-sensitivity troponin I (P =.11), N-terminal pro B-type natriuretic peptide (P =.87), right ventricular fractional area change (P =.06), left ventricular ejection fraction (P =.76), tricuspid valve pressure gradient (P =.77), or parameters related to the right heart catheter.

All-cause mortality did not differ significantly between patients with higher and patients with lower neprilysin levels (P =.53) and was not predicted by soluble neprilysin (P =.49).

Limitations to this study included a small cohort, use of exclusively hospitalization-related variables, and measurement of certain peptides but not others such as angiotensin II, endothelin-1, adrenomedullin, substance P, or bradykinin.

The study researchers concluded that “[soluble neprilysin] does not correlate with any parameters of [right heart catheterization], echocardiography, or laboratory data, including natriuretic peptides and troponin I, and is not associated with prognosis in [pulmonary hypertension] patients.”

Several authors reported associations with organizations supported by pharmaceutical companies. For a full list of author disclosures, see the reference.

Reference

Yoshihisa A, Yokokawa T, Misaka T, et al. Soluble neprilysin does not correlate with prognosis in pulmonary hypertension [published online January 25, 2019]. ESC Heart Fail. doi: 10.1002/ehf2.12404