[Clinical characteristics and CT angiography manifestations of central pulmonary artery pseudoaneurysm]

Objective: To investigate the clinical characteristics and pulmonary artery CT angiography (CTA) manifestations of central pulmonary artery pseudoaneurysms (PAPA), aiming to improve diagnostic accuracy. Methods: Twenty-three patients with complete clinical data of hemoptysis due to central PAPA admitted to Liangzhou Hospital of Wuwei City and the First Hospital of Lanzhou University from April 2019 to August 2024 were retrospectively included. There were 10 males and 13 females, with a mean age of 68 years (49-78 years). The patients were analyzed for underlying disease, CTA manifestations of the pulmonary artery of PAPA, single maximum hemoptysis and outcomes. Results: Pulmonary tuberculosis was identified as the primary etiology in 95.7% (22/23) of cases. PAPAs were located in the left inferior pulmonary artery (PA) trunk (9 cases), right inferior PA trunk (6 cases), left lower lobe basal segment PA trunk (2 cases), right lower lobe basal segment PA trunk (4 cases), left upper lobe PA trunk (1 case), and left lingular segment PA trunk (1 case). All PAPAs were solitary lesions with morphological variations: finger-like (9 cases, 39.1%, 9/23), sac-like (6 cases, 26.1%, 6/23), nodular (4 cases, 17.4%, 4/23), beak-like (2 cases, 8.7%, 2/23), and umbrella-like (2 cases, 8.7%, 2/23). Adjacent lung tissues exhibited patchy opacities, nodules, flocculent shadows, or consolidation, with 56.5% (13/23) of PAPAs originating from cavitary walls. The mean maximum single-episode hemoptysis volume was 570 ml (range: 150-2000 ml). Thirteen patients without endovascular treatment survived for a mean of 68.5 days, whereas 10 patients with endovascular intervention survived for 709.4 days on average. Thirteen patients died of asphyxia due to massive hemoptysis and 3 died of non-hemoptysis-related causes. Conclusions: Pulmonary tuberculosis is the most common cause of central PAPAs, especially in patients with hilar-adjacent cavities. After rupture of central pulmonary artery pseudoaneurysms (PAPAs), patients experience significantly larger single-episode hemoptysis volumes, leading to high risk of asphyxia-related death. Early pulmonary artery endovascular treatment can improve prognosis and prolong survival time. Pseudoaneurysms are easily missed on axial CT images when: (1) the lesion and its parent artery are not in the same imaging plane, or (2) the lesion has a nodular or beak-like morphology.