Abstract
BACKGROUND: Chronic thromboembolic pulmonary hypertension (CTEPH) is a potentially curable cause of pulmonary hypertension, yet data from Central Asia, including Kazakhstan, remain scarce. We aimed to characterize real-world management strategies and outcomes of patients with CTEPH treated within a national referral program. METHODS: We conducted a retrospective analysis of consecutive adult patients diagnosed with CTEPH between 2018 and 2024 at the sole national CTEPH referral center in Kazakhstan. Clinical characteristics, imaging findings, and invasive hemodynamic data were compared between patients undergoing pulmonary endarterectomy (PEA) and those receiving medical therapy alone. Pre- and post-operative changes were assessed in a subgroup of surgical patients, and long-term survival was evaluated. RESULTS: A total of 110 patients were included (mean age 54 ± 12 years; 58% male), of whom 56 (50.9%) underwent PEA. The median delay from symptom onset to referral was 24 months. No significant differences in baseline hemodynamic parameters were observed between surgical and medical groups. Among patients with available paired data, PEA was associated with substantial improvements in pulmonary hemodynamics, right-heart function, exercise capacity, and biomarkers of cardiac stress. Over a median follow-up of 39 months, survival was numerically higher in the surgical group, although this difference did not reach statistical significance. The estimated nationally diagnosed catheter-confirmed CTEPH detection rate was low, whereas the annual number of PEA procedures increased over time. CONCLUSION: Outcomes of PEA in Kazakhstan fall within the ranges reported in international surgical series. These findings highlight the need for earlier diagnosis, structured post-pulmonary embolism surveillance, and centralized multidisciplinary care to improve access to curative treatment in emerging healthcare systems. The observed nationally diagnosed detection rates likely underestimate the true population burden of CTEPH.