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Page 2 of 11 Raja. Vessel Plus 2019;3:23 I http://dx.doi.org/10.20517/2574-1209.2019.05
[1]
importance for patients with coronary artery disease . The choice of the graft conduit for CABG has
significant impact both on the short- and long-term outcomes. The patency of a coronary conduit is
fundamentally related with a smooth postoperative course, improved long-term patient survival and
[2]
enhanced freedom from re-intervention . Long saphenous vein has been the most commonly used conduit
in CABG. However, progressive saphenous vein graft (SVG) failure remains a major impediment to the
[3]
long-term success of CABG . Total arterial coronary grafting also known as total arterial revascularization
(TAR) is a logical solution to deal with late vein graft atherosclerosis, and occlusion.

RATIONALE
Arterial coronary grafts are relatively resistant to atheromatous changes and have better patency rates,
resulting in less recurrent angina, fewer myocardial infarctions and reoperations and better survival
[4]
than with SVGs . Hence it is logical to use arterial grafts instead of SVGs. Multiple large studies have
[5-7]
documented better long-term outcomes for CABG with two internal mammary arteries (IMAs) over one .
Arterial grafts (unlike SVGs) also synthesize and release nitric oxide and other favorable vasoactive agents
[8]
that protect the coronary artery downstream from development of further atheromatous changes .

CURRENT UTILIZATION RATES
Utilization rates of TAR are variable. It is estimated that about 20% CABG procedures in Europe utilize
TAR while utilization rates are up to 80% at some centers in Australia. On the other hand, in North
America almost 5% of patients undergoing CABG receive TAR [9-11] . This large variation in practice can
be partially attributed to the paucity of evidence from adequately powered randomized controlled trials
(RCTs) with long-term follow-up. Furthermore, increasingly complex patient profiles and enhanced
scrutiny facing the cardiac surgeons in an era of public reporting of surgeon-specific mortality data may
also impact adoption rates of TAR.

CONFIGURATIONS
The deployment of arterial grafts and their configuration is generally dictated by the availability of
conduits, the degree of stenosis in the native coronary arteries and the technical expertise of the surgeon.
There are numerous potential configurations that can be achieved during TAR highlighting the fact that
that there is no single operation that is suitable for every patient - it is not a case of “one size fits all” as
[12]
would be the scenario for the use of a single internal mammary artery and supplemental vein grafts .

Bilateral internal mammary arteries
Several configurations have been used to accomplish TAR of left-sided coronary system with bilateral
[13]
internal mammary arteries (BIMA) only . These include in situ right internal mammary artery (RIMA)
to the left anterior descending (LAD) artery and the left internal mammary artery (LIMA) to circumflex
[14]
marginal branches [Figure 1], routing the RIMA through the transverse sinus in a retroaortic course [15]
[Figure 2], and free RIMA grafts anastomosed proximally either to the LIMA [Figure 3] or to the
[16]
[17]
ascending aorta . Table 1 summarizes the pros and cons of these configurations.
Radial artery
The radial artery can be combined with BIMA to achieve TAR. The radial artery from the aorta to the
posterior descending artery (PDA) is an attractive approach in the presence of 80% or more stenosis in
the right coronary artery (RCA) or ideally if the RCA is completely blocked thereby reducing competitive
flow [Figure 4]. An alternative strategy, especially if a no touch aortic technique is indicated, is to use
the main body of the RIMA to construct a composite left-sided graft while anastomosing the radial
[12]
artery to the proximal in situ RIMA . The RIMA will frequently fail to reach the PDA even after full