Nakanishi N, et al. - Balloon pulmonary angioplasty (BPA) has been recently reported to be effective for treating patients with chronic thromboembolic pulmonary hypertension (CTEPH) considered inoperable, but potentially life-threatening vascular complications are concerning, so researchers investigated whether morphological evaluation of organized thrombus and vascular injury by BPA can improve the efficacy and safety of BPA. They found that visualization of various forms of organized thrombi such as ‘Mesh’, ‘Slit’, ‘Flap’ and ‘Mass’ was possible with angioscopy, and it enabled a detailed assessment of organized thrombus that would have been difficult by conventional contrast angiography. Also, a hemorrhage as a result of vessel wall injury caused by wiring and/or ballooning was discovered by angioscopy following balloon dilation for BPA. Overall, treatment could be improved via assessment of organized thrombus and vascular injury by angioscopy.