INDIPENDENT PROGNOSTIC VALUE OF SOLUBLE–SUPRESSION OF TUMORIGENICITY (S–ST2) IN PATIENTS AFFECTED BY PULMONARY HYPERTENSION

According to ESC 2022 guidelines, pulmonary hypertension (PH) is a hemodynamic condition characterized by mean pulmonary arterial pressure>20 mmHg. Pulmonary arterial hypertension (PAH) represents 5% of the PH, with an unfavorable prognosis primarily because of late diagnosis and treatment. In PAH, it is important to evaluate the individual patient mortality risk through a multiparametric approach: a three–layer model at diagnosis and a four–layer model based on WHO–FC, 6MWD and NT–proBNP at follow up, which allows better discrimination within the intermediate risk group helping therapeutic decision making. The only biomarker included in risk stratification is NT–proBNP; however, in previous studies soluble–Supression of Tumorigenicity 2(s–ST2), a marker of myocardial stress, resulted a strong predictor of death in heart failure and acute coronary syndromes.

The aim of this study is to analyze the prognostic value of s–ST2 in patients with pulmonary hypertension.

This is a prospective study conducted on 45 PH patients (75% PAH), which were followed for survival. They underwent echocardiography, venous sampling to measure s–ST2 levels, right heart catheterization. All the patients were followed for survival.

During an average 18–month follow–up, 17 patients died, 76% of whom had pulmonary arterial hypertension (PAH). They showed significantly higher values of s–ST2. sST2>78 ng/ml represents a numerical value with the highest association with mortality in our study population: at 6–12 months the patients with sST2>78 ng/ml showed statistically significant early higher mortality in comparison with sST2 <78 ng/ml patients (Fig. 1). At multivariate analysis s–ST2>78 ng/ml is confirmed to be a statistically significant predictor of mortality, regardless of WHO functional class III–IV, PAPs and NT–proBNP. Furthermore, s–ST2 appears a better early mortality predictor than NT–proBNP, at the limit of statistical significance (Fig. 2).

In a population of patients with pulmonary hypertension (predominantly PAH) we define a numerical value of sST2>78 ng/ml, which is a prognostic discriminator, independent and incremental to NT–proBNP at short–term follow–up. It allows the clinician the appropriate planning of therapeutic strategies in a condition in which the earliness of therapy affects prognosis.