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Machiraju. Vessel Plus 2019;3:25 I http://dx.doi.org/10.20517/2574-1209.2019.008 Page 5 of 8

of bypassing all the blood vessels both in the back and on the lateral wall of the heart with-out much
hemodynamic compromise. Avoiding the heart lung machine eliminated the complications related to
it, and also decreased the cost of the procedure which in turn contributed to the exponential growth of
CABG surgery in the third world countries. In the hands of less skilled surgeons the procedure instead
of becoming a “beating heart surgery” became a “beat the heart” surgery. Intra operative conversion
from off-pump to on-pump surgery showed increased perioperative morbidity and mortality. Off-pump
surgery became an accepted approach when the ascending aorta appeared calcified and the chances of
[7]
[12]
atherosclerotic emboli to the brain from the aorta are considered high . Benedetto et al. reviewed CABG
patients that had surgery at Bristol Heart Institute, in England both off-pump 7427 pts and on-pump 7128
pts and showed that patients who had multiple bypass grafts lived longer when compared to the patients
[13]
that had fewer number of grafts. Afilalo et al. published meta-analysis and meta-regression of 8961
patients and found that there is 30% stroke reduction in off-pump coronary artery bypass while mortality
and myocardial infarction rates are the same in both groups. The decrease in stroke rate is attributed to
avoidance of aortic manipulation. The benefit is apparent when aorta is not at all touched, but if the aorta
is partially occluded to perform proximal anastomosis the risk of stroke is reintroduced whether the
procedure performed is on-pump or off-pump. Because of the improvements in myocardial protection,
now most procedures are performed on cardiopulmonary bypass with single aortic cross clamping.

The ROOBY trial studied 2203 patients randomized to either off or on pump CABG from 2002-2007. The
5-year mortality was 11.9% in on-pump vs. 15.2% in the off-pump group . The on-pump patients required
[14]
fewer coronary interventions in the subsequent years. Now off-pump CABG is falling out of favor for triple
vessel disease and can still be used for isolated one or two vessel disease involving anterior targets.

Minimally invasive procedures such as mini-thoracotomy along with endoscopic and robot assisted CABG
procedures evolved but could not gain popularity as the cost and time involved to learn the required
minimal skills is high and protracted.

SURGERY VS. PCI
In randomized studies comparing PCI vs. surgery, patients who underwent complete revascularization
performed better when compared to patients with incomplete revascularization. When PCI is guided
by the fractional flow reserve (FFR) evaluation, there may be fewer number of stent placements when
compared to the angiographic observation of stenosis in the coronary arteries. It is still considered as CR
as there is substantial evidence that FFR above 0.8 can be treated medically and does not need therapeutic
[15]
intervention . Tackling the culprit vessel fared well when patient came to the hospital with acute ST
segment elevation myocardial infarction. While some cardiologists performed multiple vessel PCI at the
same time, majority preferred multiple staged procedures requiring repeated interventions and hospital
admissions. In arterial revascularization therapy study 1143 patients that were randomized for either
surgery or angioplasty, the patients that had complete revascularization performed better when compared
[16]
to the patient that had incomplete revascularization with angioplasty .

BYPASS CONDUITS
Saphenous vein quality is influenced by patient’s age, sex, past history of phlebitis, pregnancy, and
occupation. The technique of saphenous vein harvest also undergone several surgical modifications starting
from one large skin incision from groin to the ankle to multiple skip incisions and finally endoscopic
removal. There is no uniform standard for vein preservation solution. Perioperative use of antiplatelet
agents and statin therapy have increased the vein graft patency as well the longevity. Endoscopic removal
of the saphenous vein has become the standard practice for both cosmetic reasons as well as avoiding
wound healing complications in the leg with open surgical removal. Saphenous vein is more adoptable and