the old technique with Sephanous vein (SV) had disadvantage of limited long term patency which coincides with recurrence of the ichemic events like angina and MI in patients even after CABG. Advance atherosclerotic desease is confirmed angiographically in SV graftin symtomatic patients with CABG. Arguably a graft from low pressure system shows accelerated desease process then graft from high pressure system.

As alternative is use of Left and Right Internal Mammary artery (LIMA and RIMA)(otherwise known as internal thoracic artery (ITA)), and subsequently improved long term survival benifit, leading to the rational of total arterial revascularisation. Presently standard procedure involves LIMA-LAD (Left anterior Descending artery) graft with other vessels grafted by either SV, RIMA or Radial.

Bilateral IMA had certain disadvantages like poor sternal healing etc. and not recommanded in very obese and diabetic patient to name few.

Radial artery provides alternative graft and harvested only in patient with intact superficial palmer arch, confirmed by modified Allen's test and colour dopler preoperatively and back bleeding intraoperatively.

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Cheers
Bhuvensh Shah