INVOLVEMENT OF THE PULMONARY ARTERIES IN PATIENTS WITH TAKAYASU ARTERITIS

Background: Takayasu arteritis (TA) is a chronic, granulomatous large-vessel vasculitis. It involves the aorta and its main branches predominantly, and leads to vascular thickness, stenosis and occlusion [1]. Besides the aorta and its branches, pulmonary arteries (PAs) are involved in TA. PAs have been reported to be involved in 6.9% to 80% of TA patients from different populations [2-3]. Objectives: We investigated the clinical characteristics, pulmonary parenchymal features and cardiac functions in TA patients with PA involvement by combining multiple imaging modalities (MRA, CTA, PET-CT, lung VQ scan, echocardiography and high-resolution computed tomography (HRCT)). Our aim was to elicit better understanding of TA patients with PA involvement to aid rational treatment for these patients and improve their prognosis. Methods: We enrolled 216 patients with TA from a large prospective cohort. PAI was assessed in each patient based on data from magnetic resonance angiography/computed tomography angiography. Pulmonary hypertension, cardiac function, and pulmonary parenchymal abnormalities were evaluated further in patients with PAI based on echocardiography, New York Heart Association Functional Classification and pulmonary computed tomography, respectively. These abnormalities related to PAI were followed up to evaluate treatment effects. Results: PAI was detected in 56/216 (25.93%) patients, which involved the pulmonary trunk, main PAs and small vessels in the lungs. Among patients with PAI, 28 (50%) patients were accompanied by pulmonary hypertension, which was graded as ‘severe’ in 9 (16.07%), ‘moderate’ in 10 (17.86%) and mild in 9 (16.07%). Forty (71.43%) patients had cardiac insufficiency (IV: 6, 10.71%; III: 20, 35.71%; II: 14, 25.00%). Furthermore, 21 (37.50%) patients presented with abnormal parenchymal features in the area corresponding to PAI (e.g., the mosaic sign, infarction, bronchiectasis). During follow-up, two patients died due to abrupt pulmonary thrombosis. In the remaining patients, the abnormalities mentioned above improved partially after routine treatment. Conclusion: PA involvement is very common in TA patients. Physicians should be alerted to PA involvement even if obvious pulmonary symptoms are absent because they can cause PH, cardiac insufficiency as well as pulmonary parenchymal lesions, which will worsen the prognosis. References: [1]M.L.F. Zaldivar Villon, J.A.L. de la Rocha, L.R. Espinoza. Takayasu Arteritis: Recent Developments. Curr Rheumatol Rep 2019; 21: 45. [2]N. Matsunaga, K. Hayashi, I. Sakamoto, et al. Takayasu arteritis: protean radiologic manifestations and diagnosis. Radiographics 1997; 17: 579-594. [3]M. Bicakcigil, K. Aksu, S. Kamali, et al. Takayasu’s arteritis in Turkey - clinical and angiographic features of 248 patients. Clin Exp Rheumatol 2009; 27: S59-64. Acknowledgments: None Disclosure of Interests: None declared