Balloon Pulmonary Angioplasty in the Management of Chronic Thromboembolic Pulmonary Hypertension

Chronic thromboembolic pulmonary hypertension (CTEPH), which is classified as group 4 pulmonary hypertension (PH) in the 2015 European Society of Cardiology/European Respiratory Society guidelines for the diagnosis and treatment of PH, is regarded as a complication of pulmonary embolism and is caused by the transformation of incompletely resolved thrombi into fibrous tissue that occludes the pulmonary arteries. The current established reference standard curative therapy for CTEPH is pulmonary endarterectomy (PEA), which provides good long-term outcomes with a low mortality rate. For patients with inoperable disease with inaccessible lesions and risk factors for surgery or patients who are diagnosed with residual or recurrent PH after PEA, medical therapy with riociguat is recommended. Balloon pulmonary angioplasty (BPA) is an emerging alternative treatment option for patients with inoperable disease or those with residual or recurrent PH after PEA. BPA has been reported to improve hemodynamics, cardiac function, exercise capacity, and symptoms, as well as PEA. A detailed assessment of thromboembolic lesions in pulmonary arteries by using multiple imaging techniques and treatment strategies with multiple staged procedures based on the patient's condition is important for safe and effective BPA. However, this new technique may still induce life-threatening complications, such as reperfusion pulmonary edema, wire perforation, vessel dissection, and vessel rupture. Meticulous attention to technique is mandatory to minimize serious complications owing to the nature of the anatomic territory involved. The authors summarize the current roles, goals, and complications of BPA in patients with CTEPH and demonstrate ways to formulate an effective and safe treatment strategy. The future perspective of BPA is also discussed.