Ann Thorac Surg 1999;67:629-631
© 1999 The Society of Thoracic Surgeons
Original Articles
Inverted T graft: novel technique using composite radial and internal thoracic arteries
Tadashi Tashiro, MDa,
Katsuhiko Nakamura, MDa,
Akio Iwakuma, MDa,
Ryuzi Zaitu, MDa,
Hidehiko Iwahashi, MDa,
Akira Murai, MDa,
Michio Kimura, MDa
a Department of Cardiovascular Surgery, University of Fukuoka School of Medicine, Fukuoka, Japan
Accepted for publication July 28, 1998.
Address reprint requests to Dr Tashiro, Department of Cardiovascular Surgery, University of Fukuoka School of Medicine, 7-45-1 Nanakuma, Jonanku, Fukuoka 814-80, Japan
e-mail: tashirot{at}msat.fukuoka-u.ac.jp
 |
Abstract
|
|---|
Background. Multiple arterial revascularization is feasible because of the excellent long-term patency of the arterial grafts compared with venous grafts. We present a new operative technique for multiple arterial revascularization using composite radial and internal thoracic arterial grafts.
Methods. Between January and September 1997, 12 patients had coronary artery bypass grafting with inverted T graft. The indications for inverted T graft were aortic calcification in 4 patients, repeat coronary artery bypass grafting in 1 patient, and total arterial revascularization in 7 young patients. The inverted T graft was constructed by interconnecting the coronary arteries and radial artery with end-to-side and side-to-side anastomoses, and by anastomosing the internal thoracic artery to the side of radial artery.
Results. Overall, 38 distal anastomoses (average number per patient, 3.2) were made with an inverted T graft. There were no deaths or perioperative myocardial infarctions. Postoperative angiography disclosed that all of the anastomoses were patent.
Conclusion. This technique allows multiple arterial revascularizations without technical difficulty. It is useful in patients with aortic calcification, repeat coronary artery bypass grafting patients, and young patients who are candidates for total arterial revascularization.
|
Introduction
|
|---|
The superior long-term patency rate of the grafted internal thoracic artery (ITA) is widely documented [1–4]. For this reason, arterial conduits are believed to be superior to the saphenous vein for coronary artery bypass grafting (CABG), and several new arterial conduits have been tested. One of them, the radial artery (RA), has been used in CABG with satisfactory results [5–8]. The use of the RA as a bypass graft presents several technical advantages [5–10]. The increased wall thickness, greater luminal diameter, and longer conduit length compared with other arterial conduits facilitates sequential coronary anastomoses. For these reasons, we extended the sequential RA grafting to inverted T grafting (Fig 1).
|
Material and methods
|
|---|
Between January and September 1997, 12 patients had CABG with inverted T graft. These patients, 2 women and 10 men with a mean age of 57.7 years (range, 30 to 75 years), accounted for 14% of the total number of patients who had CABG during that period. The indication for inverted T graft was aortic calcification in 4 patients, repeat CABG in 1 patient, and total arterial revascularization in 7 young patients (Table 1).
All operations were performed through a median sternotomy. The ITA was harvested as a semiskeletonized graft [11]. The RA was harvested by a method previously reported [5, 8]. All patients received intravenous diltiazem, started intraoperatively and continued in the intensive care unit at the dose rate of 1 µg/kg per minute. This medication was administered orally throughout the follow-up period (100 mg/day). After intravenous administration of heparin, the distal edge of the artery (ITA and RA) was cut. The arteries were cannulated with a 1-mm elastic needle through which 10 mL of a solution containing papaverine (1 mg/mL of normal saline solution) was injected gently. A hemostatic clip was applied distally to allow the artery to dilate under arterial pressure. The ascending aorta or aortic arch was cannulated. A two-stage venous cannula was introduced into the right atrium, and a coronary sinus catheter was placed for retrograde perfusion during cardioplegia. A left ventricular venting line was placed through the right upper pulmonary vein. Cardiopulmonary bypass was carried out under normothermic conditions (34°C). The myocardium was protected with retrograde continuous tepid blood cardioplegia. All anastomoses were completed during the arrest period using a single cross-clamping technique. For the patients with aortic calcification, we used subclavian arterial cannulation, systemic hypothermia at a rectal temperature of 28°C, and ventricular fibrillation without aortic clamping. For these patients, the aortic no-touch technique [12] was possible.
The anastomoses of the RA to the coronary artery were made by continuous suturing with single 7-0 polypropylene suture in end-to-side and side-to-side fashion with the diamond-shaped technique [13]. An end-to-side anastomosis of the RA to the coronary artery was done first, followed by side-to-side anastomoses and end-to-side anastomosis. Thereafter, the distal end of the ITA (in situ or free) as an inflow conduit was anastomosed to the side of the RA (Fig 1). When a free ITA was used, the proximal anastomosis of the free ITA to the aorta, punched out with a 3-mm aortic punch, was made with continuous suturing with single 6-0 polypropylene suture. For dissection, preparation, and anastomoses, 2.5x magnification was used.
|
Results
|
|---|
Overall, 47 distal anastomoses were made (average number per patient, 3.9; range, 3 to 5), of which 38 were with inverted T grafts (average number, 3.2; range, 2 to 4) and nine were with a single attached ITA. The mean aortic cross-clamp time and duration of cardiopulmonary bypass were 90 minutes (range, 80 to 100 minutes) and 130 minutes (range, 81 to 170 minutes), respectively. All 12 patients are alive and well. There was no perioperative myocardial infarction or stroke. Angiography performed in the early postoperative period in all patients showed that all anastomoses were patent (Fig 2). All patients were asymptomatic and had negative results of stress test. Postoperative angiography and the stress test were performed during the same hospitalization as a routine examination.
View larger version (47K):
[in this window]
[in a new window]
|
Fig 2. (A) Diagram of the operative method and (B) angiography by injection of contrast into the free right internal thoracic artery, in the right anterior oblique view. The radial artery (RA) was sequentially grafted to the diagonal branch (Dx), obtuse marginal branch (OM), and right posterior lateral branch (RPL). The free right internal thoracic artery (RITA) was anastomosed to RA to join the RA to the ascending aorta. The left internal thoracic artery (LITA) was anastomosed to the left anterior descending artery (LAD).
|
|
|
Comment
|
|---|
The long-term results for myocardial revascularization improved after introduction of one or both ITA [1–4]. Consequently, the ITA is used increasingly in primary or repeat operations. However, multiple or total arterial revascularization is not always feasible with both ITA. The advantage of the RA is particularly apparent when it is used as a sequential bypass conduit. We started using the RA for CABG in February 1996. To date we have used 35 RA, 22 of which for sequential grafts. Based on our experience, we extended the sequential RA grafting to inverted T graft technique for total or multiple arterial myocardial revascularization.
Several techniques have been reported to provide wider arterial myocardial revascularization. Tector and colleagues [14] reported a T graft technique with composite ITA conduits. Calafiore and associates [6] reported several intricate methods using composite arterial conduits with a Y graft technique. In their technique, the free arterial conduit is anastomosed to the side of the attached left ITA. Sauvage and associates [15] reported complete revascularization of the left ventricle with bilateral free ITA grafts. In their technique, one free ITA is interconnected with the coronary arteries, and the other ITA is anastomosed to the interconnected ITA to join this artery to the ascending aorta.
However, the end-to-side anastomosis in the Y graft technique could easily result in stenosis of the attached left ITA in a patient with small body build. In Japanese patients, the diameter of the ITA is small because of the small physique. If stenosis of the attached left ITA does occur, it will result in poor bypass flow to the left anterior descending artery or to the other coronary arteries. Whereas the small diameter of the ITA precludes its use for complex composite or sequential anastomoses, the greater diameter of the RA, even in Japanese patients, makes it feasible for use in complex sequential anastomoses. In the inverted T graft technique, sequential anastomoses are made using the RA and the ITA anastomosed to the side of the RA, but no anastomosis is made to the side of the ITA. Because of the greater diameter of the RA, the risk of stenosis at the anastomosis is reduced.
This inverted T graft technique allows total arterial revascularization without technical difficulty. If the in situ ITA is used as an inflow conduit, the aortic no-touch technique [12] is possible. This technique is useful in patients with aortic calcification, patients scheduled to have repeat CABG, and young patients who are candidates for total arterial revascularization.
|
References
|
|---|
-
Lytle B.W., Loop F.D., Cosgrove D.M., Ratliff N.B., Easley K., Taylor P.C. Long-term (5 to 12 years) serial studies of internal mammary artery and saphenous vein coronary bypass grafts. J Thorac Cardiovasc Surg 1985;89:248-258.[Abstract]
-
Bourassa M.G., Fisher L.D., Campeau L., Gillespie M.J., McConney M., Lesperance J. Long-term fate of bypass grafts: the Coronary Artery Surgery Study (CASS) and Montreal Heart Institute experience. Circulation 1985;72(Suppl 5):71-77.
-
Fiore A.C., Naunheim K.S., Dean P., et al. Result of internal thoracic artery grafting over 15 years: single versus double grafts. Ann Thorac Surg 1990;49:202-209.[Abstract]
-
Galbut D.L., Traad E.A., Dorman M.J., et al. Seventeen-year experience with bilateral internal mammary grafts. Ann Thorac Surg 1990;49:195-201.[Abstract]
-
Acar C., Jebara V.A., Portoghese M., et al. Revival of radial artery for coronary artery bypass grafting. Ann Thorac Surg 1992;54:652-660.[Abstract]
-
Calafiore A.M., Giammarco G.D., Teodori G., et al. Radial artery and inferior epigastric artery in composite grafts: improved midterm angiographic results. Ann Thorac Surg 1995;60:617-624.
-
Manasse E., Sperti G., Suma H., et al. Use of the radial artery for myocardial revascularization. Ann Thorac Surg 1996;62:1076-1083.[Abstract/Free Full Text]
-
Reyes A.T., Frame R., Brodman R.F. Technique for harvesting the radial artery as a coronary artery bypass graft. Ann Thorac Surg 1995;59:118-126.[Abstract/Free Full Text]
-
Van Son J.A.M., Smedts J., Vincent G.J., Van Lier H.J.J. Comparative anatomic studies of various arterial conduits for myocardial revascularization. J Thorac Cardiovasc Surg 1990;99:703-707.[Abstract]
-
Acar C., Jebara V.A., Portoghese M., et al. Comparative anatomy and histology of the radial artery and the internal thoracic artery: implication for coronary artery bypass. Surg Radiol Anat 1991;13:283-288.[Medline]
-
Horii T., Suma H. Semiskeletonization of internal thoracic artery: alternative harvesting technique. Ann Thorac Surg 1997;63:867-868.[Abstract/Free Full Text]
-
Suma H. Coronary artery bypass grafting in patients with calcified ascending aorta: aortic no-touch technique. Ann Thorac Surg 1989;48:728-730.[Abstract]
-
Rakin J.S., Newman G.E., Bashore T.M., et al. Clinical and angiographic assessment of complex mammary artery bypass grafting. J Thorac Cardiovasc Surg 1986;92:832-846.[Abstract]
-
Tector A.J., Amundsen S., Schmahl T.M., Kress D.C., Peter M. Total revascularization with T grafts. Ann Thorac Surg 1994;57:33-39.[Abstract]
-
Sauvage L.R., Wu H.D., Kowalsky T.E., et al. Healing basis and surgical techniques for complete revascularization of the left ventricle using only the internal mammary arteries. Ann Thorac Surg 1986;42:449-465.[Abstract]
This article has been cited by other articles:
|
|
|
|
 
C. F. Chong
Reply to the Editor:
J. Thorac. Cardiovasc. Surg.,
March 1, 2009;
137(3):
785 - 786.
[Full Text]
[PDF]
|
|
|
|
|
|
|
Y. J. Woo and T. J. Gardner
Myocardial Revascularization with Cardiopulmonary Bypass
Card. Surg. Adult,
January 1, 2003;
2(2003):
581 - 607.
[Full Text]
|
|
|
|
|
|
|
T.-P. Tsai
Using saphenous vein segments to extend internal mammary conduits during MIDCAB when arterial interposition grafts are contraindicated: intermediate term results
Ann. Thorac. Surg.,
October 1, 2000;
70(4):
1446 - 1446.
[Full Text]
[PDF]
|
|
|
|
|
|
|
C. F. Chong
New method of myocardial revascularization with the radial artery
Ann. Thorac. Surg.,
January 1, 2000;
69(1):
318 - 318.
[Full Text]
[PDF]
|
|
|
Top
Abstract
Introduction
