後天性三尖弁膜症に対する外科治療と問題点について—弁輪縫縮術（DeVega法）の評価と弁置換術との比較検討

Surgical management of aquired tricuspid valve disease:The effects and comparison of tricuspid annuloplasty (DeVega) and tricuspid valve replacement

　後天性弁膜症において，三尖弁閉鎖不全（以下TR）を合併する症例は重症例が多く，他臓器障害を伴い術後に多くの問題点を残している。本症は僧帽弁膜症の22〜35％に合併し^1,2），この発生機序は，持続性肺高血圧に対応し，右室の拡大と弁輪部拡大を伴って生ずる機能的変化に基因するとされている^3,4）。本症に対する治療法として，僧帽弁病変の修復で右室機能が改善されれば，TRは放置しても改善するとの考え^3），また，外科治療として弁輪縫縮術^5），三尖弁の二尖弁化^6），リング使用弁輪形成術^7），三尖弁置換術（TVR）^8,9）等の術式が施行されているが，その治療方針はいまだ確立されていない^10,11）。

　今回，著者らは，僧帽弁単独ないし大動脈弁膜症を合併した後天性弁膜症92例について，手術術式別成績，DeVega法の術後評価を心エコー図と血行動態から検討し，あわせて弁置換症例と比較し，本症に対するDeVega法の有用性について知見を得たので報告する。

A total of 92 patients with tricuspid valvular disease (TR) had surgical repair of DeVega's an-nuloplasty in 80 patients (87%) and of valve replace-ment in 12 patients (13%) from January, 1978, to March, 1988. All of those patients were diagnosed by cardiac catheterization and angiogram, clinicalfindings and in recent cases, pulsed and color Dop-pler echocardiography were applied. Eighty-nine of 92 patients (97%) were in NYHA class or IV before operation.

There were 7 early death (8.5%) with DeVega procedure and one death (8.3%) in TVR and late deaths were noted in 3 patients (3.6%) (DeVega's procedure) and one (8.3%) in TVR. Two patients after DeVega procedure at 5 and 6 years were required re-operation of TVR because of recurrent mitral valvular disease. Seventy-seven of 80 survivors were in NYHA class I or If postoperatively. Twenty-seven randomized selected patients after DeVega's annuloplasty were investigated by pulsed and color Doppler echocardiography, 17 of them (63%) had no regurgitation and the remaining 10 patient had mild to moderate regurgitation. This study suggests that DeVega's annuloplasty has a simple and reliable procedure in patients with functional TR and results in excellent hemodynamic and functional effects postoperatively.