Lateral MIDCABを用いた再冠状動脈バイパス術 : Graft,inflow,およびgraft経路の選択における工夫

Abstract

冠状動脈バイパス術後遠隔期に回旋枝領域の虚血が出現した3症例に対し,左開胸心拍動下冠状動脈バイパス術(lateral MIDCAB)を用いて再冠状動脈バイパス術を行い良好な結果を得たので報告する.症例1)52歳男性,初回手術後11年目に狭心症が再発した.胸部下行大動脈をinflowとして肺門下経路を通した橈骨動脈(RA)を用いて,後側壁枝(PL)と鈍縁枝(OM)にsequential bypassを行った.症例2)67歳男性,初回手術後7年目に狭心症が再発した.RAでT-composite srraftを作製し,胸部下行大動脈をinflowとして肺門下経路を通してPLとOMの血行再建を行った.症例3)69歳男性,初回手術後10年目に狭心症が再発した.胸部下行大動脈に全長にわたる高度石灰化を認めたため,左腋窩動脈をinflowとして大伏在静脈(SVG)を肺門前経路を通し,開存していたSVG-PLバイパスヘ端側吻合した.回旋枝領域への再冠状動脈バイパス術を行う場合に,lateral MIDCABは非常に有用であるが,graftやgraft経路,inflowの選択には工夫を要すると考えられる.

We performed redo coronary artery bypass grafting (CABG) using lateral MIDCAB for 3 patients with severe symptomatic ischemia in the left circumflex system alone. When the descending thoracic aorta had no atherosclerotic lesions on chest CT, it was selected as the inflow of the bypass. According to the location of the target artery, we undertook sequential or T-composite off-pump bypass using the radial artery through a left lateral thoracotomy. On the other hand, when the descending aorta was diseased, the left axillary artery was chosen as the inflow of the bypass. We selected the saphenous vein as a conduit to obtain sufficient graft length. A proximal anastomosis was made through a left infraclavicular incision, and then a distal anastomosis was done through a left lateral thoracotomy without cardiopulmonary bypass. Moreover, care was taken not to kink the grafts. The postoperative course was uneventful in all patients. Lateral MIDCAB technique was useful for redo revascularization to the circumflex system. We believe that selection of bypass conduits, routes, and bypass inflow according to the individual patient is essential for the procedure.