急性大動脈弁逆流を来たした高安動脈炎の1例

Acute aortic regurgitation due to Takayasu arteritis

　高安動脈炎は大動脈および基幹動脈の原因不明の動脈炎により発現する疾患であるが，病変の分布は多様であり，ほぼ全身の動脈に波及しうる。本症の動脈病変の主たる変化は，著明な結合織の増生を伴う肉芽腫炎あるいは，びまん性増殖炎と要約でき，終局的に動脈壁全体の肥厚および内腔狭窄をもたらす。一方，拡張性病変がその主病変である場合も多いことが本症の集積とともに明らかにされ^1〜3），特に上行大動脈の拡張性病変は，本症の最も多い死因である心不全の原因となる大動脈弁逆流（AR）を合併するため，臨床的には大きな問題である。本症に伴うARは一般に慢性に経過することが多く，急性ARを来たすことは少ないとされるが，詳細は不明な点が多い。

　今回，急性ARにて肺水種を来たし，手術的治療を行った本症の一例を経験したので若干の文献的考察を含めて報告する。

We experienced a 16 year old female with acute aortic regurgitation due to annulo-aortic ectasia caused by Takayasu's arteritis. The patient was well until 3 weeks p.t.d. when she developed fever (37.5c), produ-ctive cough and slight back pain, she was hospitalized because of orthopnea. Examination on admission, blood pressure was 104/40mmHg, heart rate 96/min. and grade 3/6 systolic murmur and diastolic murmur was heared. Serologic test was negative for syphilis, tuber-culosis, antinuclear body or viral titer. Chest X-ray revealed pulmonary edema and EKG showed nonspecific ST change. Echocardiogram showed marked dilatation of aortic root with sinus of Valsalva and also early closure of mitral leaflet. Aortogram confirmed the presence of aortic regurgitaion due to annulo-aortic ectasia, but not associated with involvement of other arterial branches. Histologic study disclosed fibrous thickening of intima and adventitia, and inflammatory cells, granuloma with giant cells and destruction of smooth muscle were pre-sent in media. Clinical and histlogical features suggest Takayasu's arteritis. It is rare that acute aortic regurgita-tion due to annuloaortic ectasia without other occulu-sive change in Takayasu's arteritis.