An exploratory panel of biomarkers for risk prediction in pulmonary hypertension: emerging role of CT-proET-1.

Background: Pulmonary arterial hypertension (PAH) is a rare, deadly condition. Although risk stratification is extremely important for assessment of prognosis and to guide therapy, there is lack of evidence concerning the role of novel biomarkers. In a pivotal study, we sought to comparatively investigate the predictive power of several new biomarkers in PAH.

Methods: Patients with prevalent PAH were enrolled in the study protocol, which included clinical, functional and echocardiographic assessment. Blood samples were collected at baseline for determination of NT-proBNP, CT-proET-1, MR-proANP, MR-proADM, copeptin and troponin I. Patients were clinically followed-up up to 12 months for first occurrence of hospital admission due to PAH-related clinical worsening, heart/lung transplantation or all-cause mortality.

Results: Among the 28 included patients the pre-specified end-point occurred in 8 (29% event rate). There were higher baseline levels of CT-proET-1, copeptin, MR-proANP, NT-proBNP and troponin I in patients who reached the composite end-point. They also had larger right atria. In multivariate Cox regression, CT-proET-1 was the only biomarker associated with increased hazard of reaching the primary composite end-point (hazard ratio per tertile increase = 10.1; 95% CI 2.0 to 50.6).

Conclusions: CT-proET-1 provided prognostic information independent of other biomarkers. Importantly, we have provided the first evidence that CT-proET-1 may be superior to commonly used biomarkers.