Avulsion of an H graft during closed-chest cardiopulmonary resuscitation after minimally invasive coronary artery bypass graft surgery

Abstract

SINCE ITS FIRST DESCRIPTION by Cohn et al1 in 1998, minimally invasive coronary artery bypass graft (CABG) surgery with revascularization of the left anterior descending coronary artery (LAD) using the H graft technique has been proposed as an alternative to conventional coronary revascularization for isolated LAD occlusive disease. This approach involves access through a left anterior small thoracotomy (LAST), followed by limited dissection of the left internal mammary artery (LIMA), exposure and stabilization of the LAD, and interposition of a segment of saphenous vein or other suitable conduit between the LIMA and the LAD, without cardiopulmonary bypass. Considerable advantages of this technique include avoidance of a median sternotomy and extracorporeal circulation and dissection of only a short segment of LIMA; in contrast, the standard LAST procedure requires dissection of a longer segment of LIMA for direct anastomosis to the LAD.2 Limiting dissection of the internal mammary artery facilitates the procedure considerably and minimizes traction on the chest wall, reducing postoperative pain. Potential disadvantages of the H graft technique include a greater risk of graft kinking and the potential for a steal phenomenon, with blood flow being diverted away from the coronary system into the systemic circulation by intercostal arteries and other branches of the internal mammary artery.3 The H graft technique introduces a second anastomosis along with the interposition of an additional conduit which, as in the case of the saphenous vein, may adversely affect long-term patency rates. As a result of its location and configuration as a bridge between the LIMA and the LAD, the newly constructed H graft may become susceptible to injury in the presence of mechanical forces that alter the geometry of the thorax, such as in the case of vigorous external cardiac massage or during emergent chest re-entry. A patient in whom avulsion of a saphenous vein H graft from the LIMA occurred as a result of closed chest cardiopulmonary resuscitation (CPB) followed by emergent median sternotomy, which ultimately led to a fatal outcome, is reported.