僧帽弁形成術・maze術後に巨大左房内血栓を呈した1例

Huge Left Thrombosis after Mitral Valvuloplasty and Maze Procedure；Report of a Case

一般的に僧帽弁閉鎖不全症および心房細動の患者に対して僧帽弁形成術およびmaze手術を施行し，洞調律が維持されている状態であれば抗凝固薬は必ずしも必要ないとされている．われわれは，僧帽弁形成術後に洞調律が維持されていたにもかかわらず，左房内に巨大な血栓を認めた症例を経験したので報告する．

Generally, anticoagulation therapy is not essential for patients who maintain sinus rhythm after mitral valvuloplasty. A 66-year-old woman who had undergone mitral valvuloplasty and maze procedure for treatment of mitral valve regurgitation and atrial fibrillation 4 years ago was diagnosed as having left atrial thrombosis despite maintenance of sinus rhythm on electrocardiography. Echocardiography showed narrow mitral valvular area（1.5 cm2）, loss of A wave and a huge left atrium. Repeat surgery was performed to replace the mitral valve and to remove the thrombus. The thrombus attached to the posterior wall of the left atrium with a wide basis, and was unrelated to the ablation line of maze procedure. Careful follow-up and anticoagulation therapy should be considered for patients who have a large left atrium and/or rheumatic mitral valve after valvuloplasty even though sinus rhythm is maintained.