Operative Techniques and Revascularization Strategies
The basic surgical procedures and strategies of OPCAB and harvesting
technique of the SV have been previously described [5]. Saphenous
vein harvest was performed using an open technique. The SV from a lower
leg was chosen as opposed to the upper leg SV to decrease the
possibility of size mismatch with native coronary arteries or ITA. Prior
to October 2013, the NT SV was harvested without surrounding pedicle
tissue, in which the manipulation and tension of the SV were minimized
during harvest and manual intraluminal dilatation was avoided. The vein
was gently separated from the bed using scissors, leaving small amount
of perivascular adipose tissue in place. After October 2013, the NT SV
was harvested with surrounding pedicle tissue, whereby the SV pedicle
was harvested along with an approximately 3- to 5-mm wide margin of
adjacent adipose tissues on both sides of the SV and thin layers of
adherent connective tissues posteriorly, in addition to minimized
manipulation and avoidance of manual intraluminal dilatation of the SV.
Immediately after the harvest, the reversed SV was anastomosed to the
side of the left ITA to construct a Y-composite graft or to the distal
end of the left ITA to construct an I-composite graft. After the
Y-composite graft was constructed, the left anterior descending coronary
artery (LAD) territory commonly was revascularized first by using the
left ITA while the distal end of the SV conduit was dilated
spontaneously by the native flow and pressure of the left ITA. By using
the SV as a composite graft, the left circumflex coronary artery (LCX)
territory was then revascularized, followed by the right coronary artery
(RCA) territory. A sequential anastomotic technique was used for
complete revascularization when more than two coronary arterial
anastomoses were needed. All the diseased left coronary territories that
had had ≥70% diameter stenosis and the right coronary territories that
had had ≥90% stenosis were considered for revascularization using SV
composite grafts based on the left ITA.
We examined the anastomosis status with transit-time flow measurement
(TTFM; Medi-Stim AS, Oslo, Norway) after performing each anastomosis and
just before pericardial closure, and revised it if there was any
abnormal finding in TTFM [6]. All patients received aspirin therapy
(100mg daily) until the day of surgery and resumed it as soon as
possible after surgery, usually 1 day postoperatively. Clopidogrel (75mg
daily) was added simultaneously to aspirin for 1 year postoperatively.
If the patient had a high blood level of low-density lipoprotein
cholesterol (>70mg/dL), a statin therapy was initiated and
maintained postoperatively.