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Page 2 of 9 Dewantoro et al. Vessel Plus 2018;2:20 I http://dx.doi.org/10.20517/2574-1209.2018.50
[1]
million men and 3.4 million women died of CAD each year . Therefore, there is urgent need for prevention,
early recognition, and proper management of CAD in order to reduce mortality while also improving qual-
ity of life.

Percutaneous coronary intervention (PCI) provides a way for emergency intervention of CAD in the setting
of acute coronary syndromes and provides a less invasive intervention of CAD in stable patients. According
to an international, open-label, multicenter randomized trial that compared everolimus-eluting stents with
coronary artery bypass graft (CABG) for the management of patients with left main disease, the 3 years’ rate
of death from any cause, stroke, or myocardial infarction of PCI was higher than the CABG group at 15.4%
[2]
and 14.7% respectively. However, these differences did not seem to be very significant .
CABG is part of a routinely done revascularization intervention to manage CAD by using grafted vessels to
revascularize vessels distal from the blockage. Various grafts can be obtained from different sources, which
include veins (especially saphenous vein) and arteries (such as radial artery and internal mammary arter-
ies). This article is written to discuss the advantages and disadvantages of using each type of grafts based on
results provided by existing studies. This article is mainly aimed at comparing total arterial coronary artery
bypass graft (TACABG) with CABG that involves venous graft (VCABG) in term of benefits for patients who
suffered from CAD from the surgeon’s perspective. In common clinical practice, left anterior descending is
grafted with an arterial conduit, generally the left internal thoracic artery; other grafts could be performed
using arterial of venous conduits, with single grafts, sequential grafts or composite grafts. In TACABG, all
grafts are arterial and therefore no veins are used for revascularization, while in VCABG at least one graft
derives from a vein. In brief, differences between arterial and venous grafts will be discussed, in terms of
harvesting and complications, and then the results of the most significant clinical trials will be summarized.

DIFFERENCES IN HARVESTING BETWEEN VENOUS AND ARTERIAL GRAFTS
Grafts: complexity pre- operatively and peri-operatively
Complexity of each graft can be assessed by comparing the requirements for preparations of procedures,
time taken to do the surgery, and skills required to perform the surgery. When surgeons decided to choose
radial artery as a conduit, they need to make sure that the compensating ulnar artery is working properly,
thus, there is a need to do a modified Allen’s test. This is not the case for saphenous venous graft, which also
[3]
has the advantage of being longer and easier to handle .
During the operation, the standard procedure, according to a retrospective multicenter study, is for all pa-
tients to undergo median sternotomy for the open-heart surgery. Firstly, when internal thoracic arteries
(ITAs) (also known as internal mammary arteries, IMAs) are required, they are obtained in a skeletonized
or semi-skeletonized manner. Secondly, when radial arteries (RAs) are required, they are supposed to be
done through sharp dissection to provide open atraumatic entry and the arterial extraction would then be
supplemented by the use of low-power cautery or harmonic scalpel. Lastly, when saphenous vein grafts (SVGs)
[4,5]
are required, open entry technique in the lower leg is done while avoiding the thigh vein .

While trying to find out the average time taken to do each types of CABG, there was no studies that specifi-
cally show the total time taken for each procedure. However, operative time can be interpreted as the sum of
[6]
perfusion time (Cardio-pulmonary Bypass time) and cross clamp time . This information is available from
a retrospective study about the effectiveness of total arterial revascularization. In the study, the mean cross-
clamp time for total arterial revascularization and non- total arterial revascularization are 60.6 and 63.8 min
[4]
respectively; and the perfusion times for each groups are 80.2 and 90.7 respectively . Even though patients
are given prophylaxis antibiotics, it is logical that increased open surgery time is equal to increased risk of
infection.

Radial artery: between intrinsic limitations and clinical effectiveness
A few papers have summarized the important limitations of radial artery that need to be taken into consid-