End-to-Side Anastomosis to the Internal Mammary Artery in Free Flap Breast Reconstruction: Preserving the Internal Mammary Artery for Coronary Artery Bypass Grafting

Sir: Myocardial revascularization has become an indispensable tool in the management of ischemic heart disease over the past four decades. Because of its long-term patency as compared with venous grafts,1,2 the left internal mammary artery–to–left anterior descending artery graft has been the standard of care in bypass surgery since the mid-1980s.3 In addition, the internal mammary artery’s location, patency, and favorable diameter have also led to its routine use by plastic surgeons.1,4 Unfortunately, when the internal mammary arteries are used as the recipient vessels in microvascular breast reconstruction and anastomosed in an end-to-end fashion, they are rendered too short to reach the coronary artery, making them unavailable for future myocardial revascularization. This loss of the internal mammary artery as a potential conduit for myocardial revascularization could adversely affect some patients should they develop coronary artery disease requiring coronary artery bypass grafting. Fortunately, by anastomosing the flap’s vascular pedicle to its internal mammary recipient vessels in an end-to-side fashion, we can preserve the internal mammary artery in its distal course for future myocardial revascularization. We have performed five deep inferior epigastric perforator flap reconstructions to date using an end-to-side arterial anastomosis. All five patients have recovered without significant morbidity (Fig. 1). Our recommended surgical technique is as follows. Exposure of the internal mammary vessels is made by excising the cartilaginous portion of the third rib to create a window. We then perform the typical end-to-end venovenous anastomosis between the internal mammary vein and inferior epigastric vein with a venous coupler device or 8-0 nylon. For arterial anastomosis, a double approximating microvascular clamp for proximal and distal control of the internal mammary artery is used. Next, a circular arteriotomy with the Banis ASSI arteriotomy forceps allows for an end-to-side anastomosis between the inferior epigastric artery and the internal mammary artery by means of an interrupted 8-0 nylon suture (Fig. 2).Fig. 1.: View of a patient at 10 weeks after bilateral deep inferior epigastric perforator flap breast reconstruction.Fig. 2.: End-to-side arterial anastomosis (arrow) and end-to-end venovenous anastomosis (arrowhead) of pedicle (p) to internal mammary vessels.We know that the sternum and internal mammary artery have an extensive collateral blood supply.5 In addition, experience has shown that cutaneous perforator flaps develop rich collateral blood supplies that sustain them after their vascular pedicles are disrupted in the setting of debulking and recontouring. Considering this, should the need arise for coronary artery revascularization in one of our patients, the deep inferior epigastric pedicle can be safely divided without compromising the viability of the reconstructed breast (deep inferior epigastric perforator flap). It is entirely foreseeable that patients who have undergone the standard end-to-end anastomosis in free flap breast reconstructions may require future coronary artery revascularizations. In that event, heart surgeons and patients will face an unpleasant realization that the use of their internal mammary artery as a conduit is no longer a possibility. Because of this, the preservation of the internal mammary artery as a bypass conduit in the manner described is an option that should be widely considered in the context of free flap breast reconstruction. Admittedly, our patient population reflects the infancy of this new approach, but we will continue to use this method of vascularization with the intention of comparing our long-term results with those of the traditional end-to-end anastomoses. We would also like to explore the outcomes of myocardial revascularization using the internal mammary arteries of these patients. Amani F. Hemphill, M.D. Ramon A. de Jesus, M.D. Nathaniel McElhaney, M.D. Jonathan P. Ferrari, B.S. Department of Surgery Union Memorial Hospital Baltimore, Md.