無症状で経過した右房流入型バルサルバ洞動脈瘤破裂の1例

Rupture of an Asymptomatic Aneurysm of the Sinus of Valsalva into the Right Atrium：Case report

要旨

　患者は31歳，男性．2001年7月10日，会社の検診にて心雑音を指摘された．経胸壁心エコー図上，大動脈右冠尖から右心房にかけてのシャントが考えられ，バルサルバ洞動脈瘤破裂の疑いで当科に入院した．経食道心エコー図上，右冠動脈洞から右心房へのシャントを認め，心臓カテーテル検査ではカテーテル先端が大動脈から逆行性に右心房に入り，右心房における酸素含量のステップアップを認めた．右房流入型バルサルバ洞動脈瘤破裂の診断のもとに同年8月16日直接縫合閉鎖術が施行された．一般に右房流入型バルサルバ洞動脈瘤破裂は症状がより出現しやすいとされているが，本症例は明らかな症状を伴わず，健康診断を契機に指摘された稀な症例と思われたので報告する．

Summary

　On July 10,2001,a cardiac murmur without subjective symptoms was discovered in a 31-year-old man during a company health examination. Transthoracic echocardiography showed shunt flow from the right coronary cusp to the right atrium. He was admitted to our department immediately,suspected as having a ruptured aneurysm of the sinus of Valsalva. Transesophageal echocardiography also revealed a shunt from the right coronary cusp to the right atrium. On cardiac catheterization,oximetry showed a large left-to-right shunt of 66.4% via the fistula. The pigtail catheter passed from the sinus of Valsalva into the right atrium,just at the time when the left ventriculography was being prepared.

　Under the diagnosis of a ruptured aneurysm of the sinus of Valsalva from the right coronary cusp into the right atrium,direct suture closure was performed on August 16,2001. Generally,a ruptured aneurysm of the sinus of Valsalva into the right atrium can be detected from its associated symptoms. This rare asymptomatic case,however,had been incidentally discovered during a physical examination as part of the health surveillance of a company. We speculated that,because the range of weak endocardial tissue was relatively small,the reason why this case occurred without any symptoms was due to the fact that the size of the fistula was small at the time of rupture.