大動脈炎症候群に伴うValsalva洞動脈瘤により進行性の房室ブロックを呈した1例

A case of advanced A-V block caused by Valsalva aneurysm in aortitis syndrome

　大動脈炎症候群では大動脈・主幹動脈・肺動脈の非特異的炎症と瘢痕線維化により，二次的に大動脈弁閉鎖不全症・狭窄性変化などの臨床症状を呈することがある。

　一方，後天性Valsalva洞動脈瘤の原因疾患としては，細菌感染・梅毒・結核等が知られているが，大動脈炎症候群に伴うものは稀である。また，Valsalva洞動脈瘤により伝導障害を呈したという報告もきわめて少ない^9〜11）。

A case of advanced A-V block, which was recovered after the operation of Valsalva aneurysm was presented. A 54-year-old female, beeing suffering from aortitis syndrome for 13 years, was admitted to the Department of Cardiovascular Medicine, Hokkaido University School of Medicine, because of palpitation and shortness of breath on exertion. On the following day of admission, she developed severe dizziness due to advanced A-V block which was firstly detected by ECG. The attachment of temporary pacemaker was effective. Echocardiography and aortography revealed a large Valsalva aneurysm at the noncoronary sinus, protruding into the atrial septum. After the operation of aortic valve replacement, her ECG turned into the 1st degree A-V block. Histological examination of the resected valve and ascending aorta disclosed the fibrosis of the media and adventitia with inflammatory cell infiltration, consistent with aortitis. Thus, it can be suggested that the cause of A-V block could be ascribed to the compression of the conduction system by a protruded Valsalva aneurysm associated with Aortitis syndrome.