- Email: [email protected]
Free splenic artery used in aortocoronary bypass
Free Splenic Artery Used in Aortocoronary Bypass Dale K. Mueller, MD, Bradford P. Blakeman, MD, and Jack Pickleman, MD Department of Thoracic and Cardiovascular Surgery, Loyola University Medical Center, Maywood, Illinois
Many alternative bypass conduits for coronary revascularization have been used since the introduction of the saphenous vein. The internal mammary artery has demonstrated superior long-term patency rates compared with vein grafts. Other arterial grafts previously investigated include the right gastroepiploic artery, inferior
epigastric artery, radial artery, and splenic artery. This case reports bypass using a free splenic artery and a pedicled right gastroepiploic artery, each with successful postoperative patency.
A
ortocoronary bypass grafts have extremely high patency rates with the use of the internal mammary artery (IMA). Use of the saphenous vein as an arterial conduit also provides for excellent revascularization. Because of the need for additional conduits, particularly in redo revascularization cases, alternative arterial grafts have been investigated including: (1)right gastroepiploic artery (RGEAJ, (2) inferior epigastric artery, (3) radial artery, and (4) splenic artery. The splenic artery has been used only as a pedicled graft, whereas the IMA and RGEA arteries have been used both as a free graft and as a pedicled graft [I, 21. The radial artery and inferior epigastric artery for obvious reasons have only been used as a free graft [>5]. Reported is a case in which the splenic artery as a free graft and an in-situ RGEA were used with successful postoperative patency.
been attempted with dismal results. Aortocoronary bypass grafting was performed using the RGEA anastomosed to the obtuse marginal artery and the free splenic artery to the left anterior descending artery. Excellent Doppler pulses were present for both grafts. The patient’s postoperative course was complicated by pneumonia, bacteremia, and a urinary tract infection. The patient at 7 months is asymptomatic and has demonstrated no clinical signs of ischemia. An adenosine thallium stress test was obtained postoperatively and demonstrated no areas of reversible ischemia. Because of severe peripheral vascular disease, it was decided not to repeat coronary angiography. In fact, since the operation the patient has required an axillo bifemoral artery bypass graft.
The patient was a 67-year-old woman who came to the emergency room complaining of chest pain, dyspnea, and orthopnea. Medical history revealed the patient had coronary artery bypass grafting four times-the two most recent with cadaver veins. Coronary angiography showed thrombosis of the recent cadaver vein grafts to the left anterior descending and the obtuse marginal arteries. During the angiography the patient complained of rest angina requiring intraaortic balloon pump insertion. Thrombolytic therapy was attempted without success. No infarction had occurred, and the left ventricular ejection fraction remained 0.28. The patient was taken to the operating room for revascularization of the left anterior descending artery and the obtuse marginal artery. During the previous four operations, all greater saphenous veins, lesser saphenous veins, cephalic veins, inferior epigastric arteries, and both IMAs had been used or determined to be unsuitable for use. Cadaver veins had been used for the two most recent bypass procedures. Also, the patient had no palpable radial pulses in either arm, thereby eliminating this vessel as a potential conduit. Multiple angioplasties had also
Since the origin of coronary revascularization, surgeons and cardiologists have searched for the optimal vascular conduit. The saphenous vein graft has been the primary graft used. However, more reliable grafts have been desired because patency rates for veins are 70% to 80% in men and approximately 10% to 15% lower in women [6]. Thus far the optimal bypass graft has been the IMA [6]. Although technically more difficult, the IMA provides superior patency compared with any other graft thus far investigated. The Cleveland Clinic has recommended that the IMA be the first choice for coronary revascularization. The RGEA has also been investigated, with two studies demonstrating excellent early patency of RGEA when used as a pedicled or free graft [7, 81. Experience with the inferior epigastric artery is also limited, and current literature concerning the free radial artery demonstrates approximately 33% patency [3, 41. Edwards and associates [l] in 1973 employed the splenic artery as an in-situ graft passing through the membranous portion of the diaphragm and anastomosed to the distal right coronary artery. The splenic artery was mobilized behind the pancreas at the junction of the body and tail with obligatory splenectomy. Two postoperative splenic artery angiograms demonstrated widely patent anastomosis. Potential disadvantages of using the splenic artery were noted to be its tortuous course and larger
Accepted for publication April 9, 1992. Address reprint requests to Dr Blakeman, 2160 S First Ave, Maywood, IL 60153.
0 1993 by The Society of Thoraac Surgeons
(Ann Thorac Surg 1993;55:162-3)
Comment
Ann Thorac Surg 1993:55:162-3
diameter as compared with the right coronary artery. Edwards and associates [l]did not find these to be major problems. A free splenic artery bypass graft to the left anterior descending and a pedicled RGEA bypass graft to the obtuse marginal artery were performed in our patient. The midsternotomy incision was extended to the umbilicus. After the right gastroepiploic artery pedicle was freed, the lesser sac was entered. The splenic artery was identified along the upper border of the pancreas. Beginning at the middle of the artery, the dissection proceeded medially to its origin from the celiac axis. Multiple small branches pass from the splenic artery to the pancreas, and each was carefully ligated. Also, great care was taken to avoid any injury to the pancreas. Next the dissection proceeded laterally. Once the tail of the pancreas was reached the spleen was freed from its lateral attachments. The short gastrics were divided, and the artery was divided after branching occurred. An obligatory splenectomy was performed. The original intent was to use the splenic artery as an in-situ bypass graft for the obtuse marginal artery; however, the length was inadequate. It was therefore divided at the celiac axis and used as a free graft to the anterior descending vessel. Four technical aspects of using this vessel merit mention. First, the majority of the tortuosity can be straightened by dividing the surrounding tissue. Second, the intima was extremely friable near the splenic hilum, necessitating meticulous suturing. Third, the splenic artery possessed diffuse calcification, which made the anastomosis more difficult, but possible. Finally it must be emphasized that meticulous dissection should be performed at the upper surface of the
CASE REPORT MUELLER ET AL REVASCULARIZATION BY SPLENIC ARTERY
163
pancreas to avoid any injury of this organ and potential pancreatitis. In conclusion, this patient represents an increasing number of complex redo revascularizations that all surgeons will face. The splenic artery is offered as a potential conduit in an extremely desperate situation. Short length of the splenic artery will limit its use to the posterior descending vessel as an in-situ graft and to the anterior descending vessel or diagonal branch as a free graft. The IMA and saphenous vein graft remain the conduits of choice for most patients.
References 1. Edwards WS, Lewis CE, Blakeley WR, Napolitano L. Coronary artery bypass with internal mammary and splenic artery grafts. Ann Thorac Surg 1973;15:35-9. 2. Edwards WS, Blakeley WR, Lewis CE. Technique of coronary bypass with autogenous arteries. J Thoracic Cardiovasc Surg 1973;65:272-5. 3. Vincent JG, van Son JA, Shotnicki SH. Inferior epigastric artery as a conduit in myocardial revascularization: the alternative free arterial graft. Ann Thorac Surg 1990;49:322-5. 4. Curtis JJ, Stone WS, Alford WC Jr, Burrus RB, Thomas CS. Intimal hyperplasia: a cause of radial artery graft aortocoronary bypass graft failure. Ann Thorac Surg 1975;20:62%35. 5. Fisk RL, Brooks CM, Collaghan JC, Dvorkin J. Experience with the radial artery graft for coronary artery bypass. Ann Thorac Surg 1976;21:513-8. 6. Irarrazaval MJ. Use of the internal mammary artery for myocardial revascularization. Cleve Clin Q 1976;43:109-12. 7. Mills NL, Everson CT. Right gastroepiploic artery: a third arterial conduit for coronary artery bypass. Ann Thorac Surg 1989;47706-11. 8. Lytle BW, Cosgrove DM, Ratliff NB, Loop FD. Coronary artery bypass grafting with the right gastroepiploic artery. J Thorac Cardiovasc Surg 1989;97:826-31.
Many alternative bypass conduits for coronary revascularization have been used since the introduction of the saphenous vein. The internal mammary artery has demonstrated superior long-term patency rates compared with vein grafts. Other arterial grafts previously investigated include the right gastroepiploic artery, inferior
epigastric artery, radial artery, and splenic artery. This case reports bypass using a free splenic artery and a pedicled right gastroepiploic artery, each with successful postoperative patency.
A
ortocoronary bypass grafts have extremely high patency rates with the use of the internal mammary artery (IMA). Use of the saphenous vein as an arterial conduit also provides for excellent revascularization. Because of the need for additional conduits, particularly in redo revascularization cases, alternative arterial grafts have been investigated including: (1)right gastroepiploic artery (RGEAJ, (2) inferior epigastric artery, (3) radial artery, and (4) splenic artery. The splenic artery has been used only as a pedicled graft, whereas the IMA and RGEA arteries have been used both as a free graft and as a pedicled graft [I, 21. The radial artery and inferior epigastric artery for obvious reasons have only been used as a free graft [>5]. Reported is a case in which the splenic artery as a free graft and an in-situ RGEA were used with successful postoperative patency.
been attempted with dismal results. Aortocoronary bypass grafting was performed using the RGEA anastomosed to the obtuse marginal artery and the free splenic artery to the left anterior descending artery. Excellent Doppler pulses were present for both grafts. The patient’s postoperative course was complicated by pneumonia, bacteremia, and a urinary tract infection. The patient at 7 months is asymptomatic and has demonstrated no clinical signs of ischemia. An adenosine thallium stress test was obtained postoperatively and demonstrated no areas of reversible ischemia. Because of severe peripheral vascular disease, it was decided not to repeat coronary angiography. In fact, since the operation the patient has required an axillo bifemoral artery bypass graft.
The patient was a 67-year-old woman who came to the emergency room complaining of chest pain, dyspnea, and orthopnea. Medical history revealed the patient had coronary artery bypass grafting four times-the two most recent with cadaver veins. Coronary angiography showed thrombosis of the recent cadaver vein grafts to the left anterior descending and the obtuse marginal arteries. During the angiography the patient complained of rest angina requiring intraaortic balloon pump insertion. Thrombolytic therapy was attempted without success. No infarction had occurred, and the left ventricular ejection fraction remained 0.28. The patient was taken to the operating room for revascularization of the left anterior descending artery and the obtuse marginal artery. During the previous four operations, all greater saphenous veins, lesser saphenous veins, cephalic veins, inferior epigastric arteries, and both IMAs had been used or determined to be unsuitable for use. Cadaver veins had been used for the two most recent bypass procedures. Also, the patient had no palpable radial pulses in either arm, thereby eliminating this vessel as a potential conduit. Multiple angioplasties had also
Since the origin of coronary revascularization, surgeons and cardiologists have searched for the optimal vascular conduit. The saphenous vein graft has been the primary graft used. However, more reliable grafts have been desired because patency rates for veins are 70% to 80% in men and approximately 10% to 15% lower in women [6]. Thus far the optimal bypass graft has been the IMA [6]. Although technically more difficult, the IMA provides superior patency compared with any other graft thus far investigated. The Cleveland Clinic has recommended that the IMA be the first choice for coronary revascularization. The RGEA has also been investigated, with two studies demonstrating excellent early patency of RGEA when used as a pedicled or free graft [7, 81. Experience with the inferior epigastric artery is also limited, and current literature concerning the free radial artery demonstrates approximately 33% patency [3, 41. Edwards and associates [l] in 1973 employed the splenic artery as an in-situ graft passing through the membranous portion of the diaphragm and anastomosed to the distal right coronary artery. The splenic artery was mobilized behind the pancreas at the junction of the body and tail with obligatory splenectomy. Two postoperative splenic artery angiograms demonstrated widely patent anastomosis. Potential disadvantages of using the splenic artery were noted to be its tortuous course and larger
Accepted for publication April 9, 1992. Address reprint requests to Dr Blakeman, 2160 S First Ave, Maywood, IL 60153.
0 1993 by The Society of Thoraac Surgeons
(Ann Thorac Surg 1993;55:162-3)
Comment
Ann Thorac Surg 1993:55:162-3
diameter as compared with the right coronary artery. Edwards and associates [l]did not find these to be major problems. A free splenic artery bypass graft to the left anterior descending and a pedicled RGEA bypass graft to the obtuse marginal artery were performed in our patient. The midsternotomy incision was extended to the umbilicus. After the right gastroepiploic artery pedicle was freed, the lesser sac was entered. The splenic artery was identified along the upper border of the pancreas. Beginning at the middle of the artery, the dissection proceeded medially to its origin from the celiac axis. Multiple small branches pass from the splenic artery to the pancreas, and each was carefully ligated. Also, great care was taken to avoid any injury to the pancreas. Next the dissection proceeded laterally. Once the tail of the pancreas was reached the spleen was freed from its lateral attachments. The short gastrics were divided, and the artery was divided after branching occurred. An obligatory splenectomy was performed. The original intent was to use the splenic artery as an in-situ bypass graft for the obtuse marginal artery; however, the length was inadequate. It was therefore divided at the celiac axis and used as a free graft to the anterior descending vessel. Four technical aspects of using this vessel merit mention. First, the majority of the tortuosity can be straightened by dividing the surrounding tissue. Second, the intima was extremely friable near the splenic hilum, necessitating meticulous suturing. Third, the splenic artery possessed diffuse calcification, which made the anastomosis more difficult, but possible. Finally it must be emphasized that meticulous dissection should be performed at the upper surface of the
CASE REPORT MUELLER ET AL REVASCULARIZATION BY SPLENIC ARTERY
163
pancreas to avoid any injury of this organ and potential pancreatitis. In conclusion, this patient represents an increasing number of complex redo revascularizations that all surgeons will face. The splenic artery is offered as a potential conduit in an extremely desperate situation. Short length of the splenic artery will limit its use to the posterior descending vessel as an in-situ graft and to the anterior descending vessel or diagonal branch as a free graft. The IMA and saphenous vein graft remain the conduits of choice for most patients.
References 1. Edwards WS, Lewis CE, Blakeley WR, Napolitano L. Coronary artery bypass with internal mammary and splenic artery grafts. Ann Thorac Surg 1973;15:35-9. 2. Edwards WS, Blakeley WR, Lewis CE. Technique of coronary bypass with autogenous arteries. J Thoracic Cardiovasc Surg 1973;65:272-5. 3. Vincent JG, van Son JA, Shotnicki SH. Inferior epigastric artery as a conduit in myocardial revascularization: the alternative free arterial graft. Ann Thorac Surg 1990;49:322-5. 4. Curtis JJ, Stone WS, Alford WC Jr, Burrus RB, Thomas CS. Intimal hyperplasia: a cause of radial artery graft aortocoronary bypass graft failure. Ann Thorac Surg 1975;20:62%35. 5. Fisk RL, Brooks CM, Collaghan JC, Dvorkin J. Experience with the radial artery graft for coronary artery bypass. Ann Thorac Surg 1976;21:513-8. 6. Irarrazaval MJ. Use of the internal mammary artery for myocardial revascularization. Cleve Clin Q 1976;43:109-12. 7. Mills NL, Everson CT. Right gastroepiploic artery: a third arterial conduit for coronary artery bypass. Ann Thorac Surg 1989;47706-11. 8. Lytle BW, Cosgrove DM, Ratliff NB, Loop FD. Coronary artery bypass grafting with the right gastroepiploic artery. J Thorac Cardiovasc Surg 1989;97:826-31.