Total Occlusion of Right Main Pulmonary Artery in a Patient with Takayasu's Arteritis and Severe Pulmonary Hypertension
A 52-year-old woman was referred to the outpatient clinic of rheumatology department with a 6-month history of dyspnea on exertion [New York Heart Association (NYHA) functional class II to III]. About 20 years ago, she visited a local clinic for non-healing toe wound and had a tentative diagnosis of TA. She had a previous history of vascular surgery for left carotid artery. Ten years later, she visited another local clinic with a complaint of dyspnea on exertion (NYHA functional class II). At that time, echocardiographic examination showed severe pulmonary hypertension with severe tricuspid regurgitation, based on which the attending physician prescribed diuretics and digoxin with a diagnosis of idiopathic pulmonary arterial hypertension. Despite the medications, however, she could not feel any improvement with regard to exertional dyspnea and she was advised to undergo surgery for severe tricuspid regurgitation. During preoperative work-ups, complete occlusion of right main pulmonary artery was incidentally detected. For further evaluation, she was referred to our hospital.\nOn physical examination, her blood pressure was 78/39 mmHg at right arm and 99/70 mmHg at left arm. Her chest radiography showed a prominent left hilar opacity and right atrial enlargement (). Her electrocardiogram showed right atrial enlargement and right ventricular hypertrophy. Laboratory parameters included increases in erythrocyte sedimentation rate (77 mm/hr) and C-reactive protein (2.14 mg/dL).\nOn echocardiography, right ventricle (RV) was severely dilated, its wall thickness was increased, and RV systolic function was decreased. Severe tricuspid regurgitation and severe pulmonary hypertension with maximal pressure gradient of 131 mmHg were noted, as well. On basal parasternal short axis view, the blood ejected from the RV to the main pulmonary artery appeared not to cross the right pulmonary artery. When we carefully traced the proximal right pulmonary artery, we could not clearly delineate its opening (). Lung perfusion scan showed the total absence of perfusion in the right lung with partial perfusion defects in the left lung (), but no pulmonary thromboembolism was clearly demonstrated on computed tomographic pulmonary angiography. The occlusion of right main pulmonary artery and left main pulmonary artery stenosis at the entrance were also clearly demonstrated on computed tomographic angiography (). According to the result of cardiac catheterization performed elsewhere, the mean right atrial pressure was severely elevated (18.4 mmHg), and catheter was impossible to go into the right pulmonary artery. Coronary angiography demonstrated a huge left circumflex coronary artery to right pulmonary artery fistula (). Arch aortography revealed total occlusion of the left subclavian and left common carotid artery in their proximities. Right subclavian artery showed near-total occlusion, as well (). The diagnosis of TA was established based on the criteria of American college of Rheumatology for classification of TA; age at diagnosis (less than 40 years), difference in systolic blood pressure between arms (exceed 10 mmHg), arteriogram abnormality.\nThe patient was treated with corticosteroid, methotrexate, bosentan and symptomatic medications for right-sided heart failure. She is now being followed in the rheumatology clinic on a regular basis and her symptoms showed slight improvement with these medications.