INTRODUCTION
Coronary artery disease (CAD) is nowadays considered one of the leading causes of death in the developed & underdeveloped countries. Revascularization of stenotic coronary arteries greatly contributes to the treatment of CAD (53).
Currently, two well-established revascularization techniques are practiced. One is Coronary Artery Bypass graft (CABG) surgery in which autologous arteries and/or veins are used to supply blood to the coronary artery downstream to the stenotic lesion, and the other is percutaneous transluminal coronary angioplasty (PTCA) in which catheter-borne devices, including balloon, stent, atherectomy cutter, and LASER, are used to open stenosis from within the coronary artery (53).
The clinical and prognostic benefits of coronary artery bypass grafting (CABG) for certain anatomical patterns of coronary artery disease are well accepted. Most patients undergoing CABG require three or four bypass grafts and the "standard" operation uses a single left internal mammary artery (LIMA) to the left anterior descending coronary artery, and supplemental saphenous vein (SVGs) and/or radial artery grfts to the other coronary vessels (140).
The excellent early results of CABG are limited in the long term by vein graft failure. Ten years after CABG three quarters of vein conduits are blocked or severely diseased, whereas more than 90% of IMA grafts are patent and disease free. Vein graft failure leads to reduced survival, recurrent angina, late myocardial infarction, and the need for further intervention (53).
It was noticed that by 10-15 years after the initial operation up to 40% of patients may require redo CABG at increased risk and cost. Recently, total arterial revascularization (TACR), is the procedure of choice in young adults and those having porcelain aorta, bilateral saphenectomy, etc. TACR, is possible with maximum grafts using bilateral IMAs in situ or as free grafts (27) .
The main reason cited against arterial revascularization using BIMA are inadequate evidence of benefit and that it increases perioperative mortality and/or morbidity. There are several large studies that have recently reported that multiple IMA grafts offer survival advantages (decreased death reoperation & PTCA) over a single IMA graft (91).
Internal thoracic artery grafting is particularly important for patients with diabetes because survival is significantly higher in patients with diabetes after CABG compared with percutaneous transluminal angioplasty (122).
Furthermore, the higher survival in the patients with diabetes after CABG was limited to patients who received ITA grafts. Patients with diabetes represent a subgroup of those who could potentially derive the greatest benefit from bilateral ITA grafting. Unfortunately this technique is limited by the increased risk of deep sternal wound infection associated with conventional pedicled ITA harvesting.Indeed, diabetes is a well-recognized risk factor for sternal infection even in patients receiving a single ITA graft (139).
Pedicled harvesting of both ITA grafts may impair sternal wound healing by decreasing sternal blood flow, resulting in an increased risk of sternal wound infection and dehiscence (139).
The skeletonization procedure, first described by Keeley11 in 1987, involves the harvest of only the ITA without any surrounding tissue, whereas the traditional ITA harvesting technique involves the dissection of a rim of tissue (1 to 2 cm) around the ITA (89).
Skeletonization involves meticulous dissection of the ITA conduit away from the chest wall with preservation of the collateral sternal blood supply and the internal thoracic veins (45).
On the other hand, when skeletonized, the vessel loses its “milieu,” which theoretically may adversely affect its long-term resistance to arteriosclerosis (27).
This coupled with the lack of long-term patency studies of the skeletonized ITA and meticulous follow-up and confirmation by angiography raises concerns about whether this technique sacrifices the superior longevity of the conduit (45).
In this review we evaluate the available evidence on the advantages and disadvantages of skeletonization of internal thoracic artery.
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