Balloon Pulmonary Angioplasty for CTEPH: Emerging Evidence From China

Corresponding Author

Chronic thromboembolic pulmonary hypertension (CTEPH) is characterized by persistent organized thromboembolic obstruction of the pulmonary arteries and progressive vascular remodeling.^1,2 Although pulmonary endarterectomy remains the potentially curative treatment, approximately 20% to 40% of patients are deemed inoperable in clinical practice owing to distal disease distribution, advanced age, or complex comorbidities.^3,4 For this substantial patient population, balloon pulmonary angioplasty (BPA) has evolved over the past 2 decades from an exploratory intervention to a first-line, guideline-recommended therapy within the multimodal treatment strategy for CTEPH.⁵ High-quality randomized controlled trials such as RACE (RAte Control versus Electrical cardioversion) and MR-BPA (Balloon Pulmonary Angioplasty versus Riociguat in Inoperable Chronic Thromboembolic Pulmonary Hypertension) have demonstrated the superiority of BPA over medical therapy in improving hemodynamics and functional capacity, whereas data from Japanese and international CTEPH registries have further confirmed 3-year survival rates exceeding 90% in BPA-treated patients.^6,7 However, it should be acknowledged that existing long-term survival evidence derives predominantly from developed countries or high-volume referral centers with concentrated expertise and resources.^3,8 In real-world clinical practice, where disparities in health care resource allocation and patient affordability constrain treatment delivery, complete revascularization is not always achievable, leaving the long-term clinical value of partial BPA inadequately defined.⁴ Against this background, the multicenter cohort study by Zhou et al⁹ from China published in this issue of JACC: Asia, with a median follow-up of 6.0 years, timely addresses this gap and provides robust regional real-world data to inform the optimization of BPA strategies and long-term prognostic evaluation.

Follow-up data from this study showed a stepwise pattern in long-term survival benefit: patients who completed all planned sessions (full BPA) achieved the best long-term outcomes. Another particularly noteworthy finding concerns the partial BPA cohort, whose subsequent sessions were interrupted by economic or other real-world constraints. Nevertheless, these patients achieved an impressive 8-year survival rate of 70.0%, with a significantly lower risk of all-cause mortality than the conservatively treated non-BPA group.⁹ This observation, whereby “incomplete intervention” still confers meaningful prognostic benefit, can be explained by the distinctive physiological properties of the pulmonary circulation.^10,11 Clinical efficacy in the pulmonary circulation depends more on overall functional improvement than on local anatomical completeness. This may explain why partial BPA can still translate into durable survival benefit in real-world practice.

Importantly, emphasizing the benefit of partial BPA should not be interpreted as lowering the therapeutic goal for CTEPH. The data from this study continue to reinforce a central principle: patients who completed full BPA achieved the most favorable long-term outcomes, and maximal revascularization should remain the preferred strategy whenever feasible. Nevertheless, the survival profile observed in the partial BPA cohort offers a critical clinical insight: in the pulmonary circulation, meaningful clinical benefit may emerge before complete anatomical revascularization is achieved and does not necessarily depend on it.^5,12,13 This finding invites a reevaluation of the traditional endpoint criteria for BPA therapy. If clinical benefit does not necessarily require absolute anatomical patency, future studies should explore whether hemodynamic or functional thresholds, such as a defined reduction in pulmonary vascular resistance or an improvement in 6-minute walk distance, might serve as more clinically relevant interventional targets. In parallel, an individualized evaluation framework centered on pragmatic functional improvement, rather than anatomical completeness alone, may better balance procedural risk, long-term benefit, and health economic burden.

Another major strength of this study is its objective portrayal of real-world clinical challenges. Rather than reflecting an idealized and highly selected population, the study cohort provides a realistic snapshot of routine clinical practice in China. The data clearly show that socioeconomic status and financial burden substantially influence both treatment decisions and procedural completion: the proportion of patients with low socioeconomic status was significantly higher in the non-BPA group, and some patients who initiated intervention were unable to proceed beyond partial BPA because of financial constraints.⁹ These observations highlight that treatment selection in inoperable CTEPH extends beyond technical feasibility alone and is deeply shaped by affordability and access to care. Importantly, this challenge was not limited to intervention itself.

Pathophysiologically, CTEPH involves not only pulmonary large-vessel stenosis but also frequently concomitant distal pulmonary microvasculopathy.^14,15 Moreover, a substantial body of clinical evidence has already demonstrated the efficacy of riociguat in improving exercise capacity and clinical outcomes in patients with CTEPH.⁷ However, in the present study, riociguat was used in only 23% of patients. This finding underscores that the concept of comprehensive management integrating BPA with targeted medical therapy still warrants further emphasis.

In sum, this study not only provides robust real-world evidence for the long-term prognostic benefit of partial BPA, but also broadens the frame of CTEPH management beyond purely technical refinement to encompass the wider dimension of health care resource allocation. Looking ahead, the central challenge for the field will be to advance BPA techniques in parallel with reforming reimbursement policies and optimizing care pathways, ensuring that a broader patient population can access and complete guideline-directed therapy.

Funding Support and Author Disclosures

The authors have reported that they have no relationships relevant to the contents of this paper to disclose.