.Pulmonary thromboendarterectomy (PTE) is the treatment of choice for patients with chronic thromboembolic pulmonary hypertension (CTEPH) as it can remove the chronic, fibrotic, flow-limiting organized thrombi within the pulmonary arterial bed, addressing the primum movens of the disease (1). Despite significant improvement in all haemodynamic parameters, residual pulmonary hypertension (PH) is frequent after PTE, ranging from 17% to 31% (2,3). There is no clear definition of residual PH after PTE, and the actual incidence of this condition has been difficult to quantify. Usually, moderate residual PH is well tolerated by patients and, as shown by data from the United Kingdom cohort, clinically relevant residual PH after PTE mainly occur when the mean pulmonary arterial pressure (mPAP) is greater than 30–35 mmHg (3). The risk of persistent/recurrent PH in the long-term underlines the importance of a systematic patient follow-up, even after PTE. Balloon pulmonary angioplasty (BPA) has been developed as a compassionate procedure for symptomatic patients with CTEPH who are ineligible for surgery or with persistent/recurrent PH after PTE. BPA is not able to remove clots as PTE, but it is able to restore the flow by fragmenting the thrombotic and fibrotic material, resulting in hemodynamic and clinical improvement. Selection of good candidates for BPA, especially after PTE, includes a complete re-assessment of the patient with persistent symptomatic PH after PTE at least four to six months after surgery using high quality imaging techniques such as computed tomography pulmonary angiography (CTPA), selective pulmonary angiography (to provide fine details) and right heart catheterization (RHC) to assess the hemodynamic impairment. However, these imaging techniques are not widely available and require expertise.