Operative technique:
OPCAB is the default technique used by the author for isolated coronary revascularization, including emergency referrals. Surgical access was obtained through standard median sternotomy. The revascularization strategy for the SIMA group included LIMA-LAD and saphenous vein grafts (SVG) for the other targets. In the BIMA group, a LIMA-RIMA T graft was used in the majority of cases (88%) for the left-sided lesions; a free RIMA was used only in 12% of the cases. A radial artery (RA) was used as a third arterial conduit in 67 patients (20%), most commonly for the right-sided lesions, but in 16 cases was used for obtuse marginal territories.
The choice of conduits was decided upon patient baseline characteristics and anatomy and severity of the lesions. In general, BIMA is offered to young individuals (< 65 years old) with no more than 2 comorbidities out of diabetes, COPD and obesity.
LIMA was harvested following the semi-skeletonized technique whereas a fully skeletonized RIMA was preferred due to its optimized length and also to preserve some vascularization of the sternum. SVG was harvested either open or endoscopically, depending on availability of the appropriate trained personnel and resources.
OPCAB strategy included routine opening of the right pleura to allow mobilization of the heart during the lateral wall exposure, placement of a deep pericardial string to facilitate the mobilization of the heart and use of a stabilizer (Maquet Acrobat® or Medtronic Octopus®). Distal anastomoses were performed with temporary proximal vessel occlusion was undertaken to facilitate arteriotomy and intracoronary shunt insertion, following which vessel flow was restored and the distal anastomosis performed, with a bloodless field facilitated with a CO2 blower (Maquet AXIUS Blower Mister®).
Proximal anastomoses, where necessary, were performed using either a partial occlusion aortic clamp or Heartstring Proximal Seal System (Maquet®) where avoidance of aortic clamping was indicated.
The standard sequence of anastomoses consisted of distal anastomoses on the anterior wall (LAD, Diagonal), distal anastomoses on the inferior wall (RCA, PDA, LV branch), followed by proximal anastomoses (if applicable) and finally, anastomoses on the lateral wall (Intermediate, OM). If BIMA was used, the T-graft between LIMA-RIMA was constructed first and patency of the anastomosis tested.