Abstract
BACKGROUND: Chronic thromboembolic pulmonary hypertension (CTEPH) is a severe complication of acute pulmonary embolism (PE) in which delayed diagnosis significantly affects patient health outcomes. This case-control study aimed to identify a set of microRNAs (miRNAs) in plasma with diagnostic potential to differentiate patients with CTEPH from those with PE. METHODS: Two groups were analysed: 22 patients with confirmed CTEPH and 13 patients with PE, followed by validation in an independent cohort of 48 CTEPH and 37 PE patients. RESULTS: Using real-time PCR, eight miRNAs were identified as significantly different between the groups: miR-574-3p, miR-146b-5p, miR-193a-5p, miR-885-5p, miR-122-5p, miR-365a-3p, miR-142-3p and miR-192-5p. These miRNAs target key biological pathways, including vascular smooth muscle contraction, apoptosis and VEGF signalling, underlying the pathophysiology of CTEPH. The miRNA panel demonstrated strong diagnostic accuracy with an area under the curve of 0.843 in the validation cohort. CONCLUSIONS: The results highlight the potential of miRNA biomarkers as a diagnostic tool for early detection of CTEPH, representing a paradigm shift in its management, but further validation in larger cohorts is necessary to confirm their applicability. These insights could pave the way for improved clinical outcomes through timely diagnosis and targeted interventions.