Nonpenetrating stapling: A valuable alternative for coronary anastomoses?

Background. The safe development of minimally invasive coronary artery bypa ss operations might require alternatives to conventional suture-based anast omotic techniques. In this setting, nonpenetrating stapling is an attractiv e option because of its simplicity of use and potential for improved endoth elial preservation. Methods cmd Results. In the experimental part of this study, porcine intern al mammary arteries were anastomosed to left anterior descending coronary a rteries using either an 8-0 polypropylene running suture or nonpenetrating microclips (7 anastomoses in each group). The endothelium-dependent relaxat ions to bradykinin of the arterial rings bearing the anastomosis and of non instrumented rings were compared in organ chamber experiments. There were n o significant differences in maximal relaxations (mean +/- SEM) between the microclipped and sutured anastomoses (81% +/- 7% versus 74% +/- 10%), whic h were both significantly lower than those of control coronary rings (98% /- 2%, p = 0.001 versus the two anastomosed groups). Histologic examination showed a comparable preservation of the coronary and graft endothelium wit h both techniques. The clinical part of the study comprised 7 patients in w hom the left internal mammary artery was conventionary sutured to the left anterior descending whereas 13 saphenous vein grafts were anastomosed to th eir target vessels by nonpenetrating staples. There were no clip-related co mplications. An angiographic assessment of the venous grafts was performed within 10 days postoperatively in all patients. One graft is presumably occ luded. The 12 remaining conduits were patent with stapled anastomoses featu ring a widely open "shark-mouth" configuration. Conclusions. These preliminary data suggest that nonpenetrating stapling is an easy-to-use technique that competes well with conventional suturing, at least in terms of immediate results. Further studies are warranted to bett er define its potential place within the armamentarium of minimally invasiv e coronary artery bypass techniques. (C) 1998 by The Society of Thoracic Su rgeons.