Use of the left internal mammary artery (LIMA) in coronary artery bypass (CABG) procedures has led to 10 year patency rates approaching 90%, far surpassing rates for other graft types or for stents implanted percutaneously.  Anastomosed to the left anterior descending artery, the LIMA provides reassuring protection in this critical territory, however it generally involves thoracotomy.  The patency rates of non-LIMA grafts – such as the commonly used saphenous vein – are also far less and not dissimilar to stent patency rates.  Hybrid procedures with minimally invasive LIMA grafting and stenting of other diseased vessels therefore presents an attractive option for patients and physicians alike attempting to attain the ‘best of both worlds’.

Although minimally invasive surgery has often been performed though a mini-thoracotomy, in this study Bonaros et al describe their experience in 130 patients using robotically assisted endoscopic approaches for harvest and anastomosis of the LIMA in a closed chest approach that avoids median sternotomy, minimizes periprocedural pain, and allows rapid rehabilitation.  Requiring careful selection of patients devoid of severe lung disease and with well preserved ventricular function, this case series demonstrates impressive procedural success rates of 90% with an operative mortality of <1%, and rates of survival and freedom from angina of 99% and 90% respectively at 2 years.  In the vast majority of cases PCI was carried out after the surgical procedure, although in a few cases PCI occurred before surgery and surgery was completed on dual antiplatelet therapy.  About 25% of the cohort became asymptomatic after surgery and PCI was deferred.  In-patient hospital stay was not obviously reduced at a median of 6 days.

Conclusions

With the advent of robotically assisted surgery, true closed chest bypass procedures using the LIMA are possible and make hybrid revascularisation combining CABG and PCI a much more attractive prospect.  Further studies and long term comparison data will be important in further development of this approach.

• Bonaros N, Schachner T, Wiedemann D et al. Closed chest hybrid coronary revascularization for multivessel disease – current concepts and techniques from a two-center experience. Eur J Cardiothorac Surg 2011 Oct;40(4):783-7.