大動脈縮窄症と破裂脳動脈瘤の合併—例報告と文献的考察

RUPTURED CEREBRAL ANEURYSM ASSOCIATED WITH COARCTATION OF THE AORTA

　症例は33歳の女性で，右中大脳動脈瘤破裂によるくも膜下出血と脳内血腫をきたし来院した。入院時検査で大動脈縮窄症が認められ，緊急に動脈瘤頸部クリッピングと脳内血腫除去術を行い，約3カ月後に大動脈縮窄症の手術を施行し良好な結果を得た。

　大動脈縮窄症は多発性嚢胞腎とともに脳動脈瘤を高率に合併する疾患の代表とされ，脳動脈癖の発生病態に先天的要因の関与を裏付けるものとして重要視されてきた。しかし，過去の報告を総合した結果，左動脈縮窄症に脳動脈瘤を合併する頻度は必ずしも高くないこと，合併した場合は破裂（発症）しやすいこと，および若年で発症しやすいことが判明した。これは，た動脈縮窄症に伴う高血圧と動脈壁の退行性変化が脳動脈瘤の成長・破裂に重要な役割を果たしていることを示唆した。治療については，まず破裂動脈瘤に対して通常の破裂脳動脈瘤と同じ適応にて手術を行い，次に縮窄症の手術を行うべきであると考えられた。

We present a 33-year-old female who had a ruptured aneurysm at the trifurcation of the right middle cerebral artery accompanied by coarctation of the aorta. The aneurysm was successfully clip-ped 15 hours after the attack of subarachnoid hemorrhage and approximately 3 months later the coarctation was surgically treated.

Many authors reported that the incidence of cerebral aneurysm was higher in the patients with coarctation than the general population. Our re-view of the literatures, however, revealed that the incidence of cerebral aneurysm was the same in the population with or without coarctation. The incidence of rupture was higher when the aneu-rysms was accompanied by coarctation. The av-erage age of the patients at the aneurysmal rup-ture was younger in the patients with coarctation than the patients without coarctation. These find-ings suggested that the growth and rupture of aneurysm in the patient with coarctation are re-lated to the hypertension and atherosclerosis.

Treatment of the patients with intracranial rup-tured aneurysm accompanied by coarctation should begin with the clipping of the aneurysm, and then the coarctation surgically repaired. If the aneurysm is unruptured coarctation should be repaired first, and then the aneurysm clipped.