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.