Asian Cardiovasc Thorac Ann 2004;12:236-238
© 2004 Asia Publishing EXchange Ltd
Early Results and Problems with St. Jude Medical Symmetry Bypass System in Japan
Hideki Kitamura, MD,
Hitoshi Okabayashi, PhD,
Michiya Hanyu, PhD,
Jota Nakano, MD,
Satoshi Kono, PhD,
Takuya Nomoto, PhD,
Atsushi Nagasawa, MD,
Hisashi Sakaguchi, MD,
Hiroyuki Johno, MD,
Takehiko Matsuo, MD
Cardiovascular Surgery, Kokura Memorial Hospital, Fukuoka, Japan
For reprint information contact: Hideki Kitamura, MD Tel: 81 93 921 2231 Fax: 81 93 921 8497 Email: k-hideki{at}sc4.so-net.ne.jp Cardiovascular Surgery, Kokura Memorial Hospital, Kifunemachi 1-1, Kokurakitaku, Kitakyusyu City, Fukuoka 802–8555, Japan.
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ABSTRACT
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The early results of coronary artery grafting with an aortic connector system were assessed in Japanese patients. From May 2002 through April 2003, 24 consecutive patients underwent off-pump coronary artery bypass using an aortic connector system. Another patient was excluded because the saphenous vein was insufficient for the smallest available aortic connector system. Saphenous veins were harvested from the thigh in 17 (70.8%) patients, and from the lower leg in 7. The size of the aortic connector system was 4.5–5.0 mm in 19 (79.2%) patients. Intraoperative epiaortic echo indicated that a side-clamp was contraindicated in 15 cases. Hemostasis was instantaneous in all patients. There were no hospital deaths and no neurologic morbidity. Pre-discharge angiography revealed 100% patency of the anastomoses. Use of the aortic connector system demonstrated excellent early results with low neurologic morbidity even when employed in the context of an atheromatous ascending aorta. However, smaller sizes of the device are required for some Japanese patients.
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INTRODUCTION
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With advances in surgical procedures, including off-pump coronary artery bypass (OPCAB), the operative indications for ischemic heart disease have grown more diverse. However, complications of these procedures persist. In our institution, we employ OPCAB as the standard technique for achieving complete arterial revascularization. When the use of arterial grafts is inadequate for complete revascularization, vein grafts are required. Proximal anastomosis of a saphenous vein graft (SVG) is performed with a partial occlusion clamp which may generate emboli if aortic atheroma or calcification is present. The St. Jude Medical Symmetry (St. Jude Medical, Inc., Minneapolis, MN, USA) aortic connector system (ACS) is an alternative method of securing proximal anastomosis of the SVG, thereby avoiding aortic side-clamping and its complications. This retrospective study describes the early results of OPCAB using the ACS in Japanese patients.
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PATIENTS AND METHODS
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From May 2002 through April 2003, 311 patients underwent isolated coronary artery bypass grafting in our institution. Of these, 24 consecutive patients who underwent OPCAB by one surgeon, using saphenous vein grafting and proximal anastomosis with the ACS, were evaluated. The ACS was used for 24 of 25 proximal anastomoses. In one case, the SVG was anastomosed to the descending aorta, but in all others, the SVG was anastomosed to the ascending aorta. One patient was excluded because the saphenous vein was of insufficient size to support the ACS. Preoperative variables are summarized in Table 1
. Intraoperative blood flow was assessed in all grafts using a flowmeter (CardioMed; Medi-Stim, Oslo, Norway) based on the transit-time principle. Angiographic evaluation of graft patency was performed prior to hospital discharge (from postoperative day 7 to 25) in all patients.
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RESULTS
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Operative details are given in Table 2. In 15 cases, intraoperative epiaortic echo indicated the presence of atheroma or patchy calcification in the ascending aorta, to a degree that precluded the use of a side-clamp. In those patients, an appropriate site for the proximal vein graft anastomoses was selected by epiaortic echo. Before anastomoses, systemic heparinization (100 U·kg–1) was carried out. Hemostasis was instantaneous in all cases, no anastomosis leaked, and no additional stitches were required. The SVG was fixed to the epicardium with suture or fibrin glue to maintain an appropriate angle of the ACS and to prevent graft kinking when the pericardium was closed. In 21 cases, heparinization was half-neutralized with protamine sulfate following anastomoses.
The early postoperative outcomes are summarized in Table 2
. Heparin (200 U·kg–1) was administered via continuous intravenous injection or hypodermic injection from the 1st to 4th postoperative day in all patients. No patient required reexploration. Postoperative medical therapy included acetylsalicylic acid (100 mg per day) in all patients. Other antiplatelet drugs or warfarin sodium were added in 7 patients because of coexisting arterial disease (arteriosclerosis obliterans, carotid artery stenting) or atrial fibrillation. There were no operative or postoperative deaths. No neurologic morbidity, including transient ischemic attack, was noted. Angiographic evaluation before discharge revealed one patient had 50% narrowing of the left thoracic artery-to-left anterior descending artery anastomotic site, and one patient had occlusion of the distal anastomotic site of a sequential SVG graft without occlusion or stenosis of the proximal sutureless SVG anastomosis site.
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DISCUSSION
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The widespread use of OPCAB has brought more attention to its potential complications, particularly in the context of aortic atheroma or calcification.1 Use of an aortic side-clamp requires aortic manipulation, thereby precluding the major advantage of OPCAB. The ACS allows anastomosis of the proximal SVG site without the need for side-clamping.2–5 In this study, the sutureless connector system for proximal anastomosis gave excellent graft patency with adequate hemostasis. There were 15 (62.5%) cases in which use of an aortic side-clamp was impossible, but no postoperative neurologic complications occurred. The combination of an ACS and intraoperative assessment of the aorta by epiaortic echo may reduce the incidence of neurologic complications. The body habitus and saphenous vein of the Japanese population are smaller than those of Western populations. Although the SVG was harvested from the thigh in 70% of cases, one patient had a saphenous vein that was insufficient to support the smallest size of ACS. Thus, development of smaller devices may be required for the Japanese population.
There are some reports of thrombotic occlusion of the aortic ostia of the SVG early after operations with an ACS.6–8 During this study, we were trying to evaluate whether routine heparin usage could eliminate late cerebral infarction, so we administered heparin not for the device but for another study, and there happened to be no occlusion. Causes of occlusion include poor run-off at the anastomosis and an inappropriate angle of the device, which may have been avoided by the use of heparin in the early postoperative course.7 Further investigation of the long term patency with an ACS and the optimal regimen of antiplatelet medications is required, but we speculate that early use of heparin may be beneficial.
It was concluded that use of an ACS demonstrated good hemostasis and excellent early patency. Furthermore, there was low neurologic morbidity in patients with atheromatous aortic disease. However, development of smaller sizes of ACS would be helpful for Japanese patients.
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REFERENCES
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- Tozzi P, Corno AF, von Segesser LK. Sutureless coronary anastomoses: revival of old concepts. Eur J Cardiothorac Surg
2002;22:565–70.[Abstract/Free Full Text]
- Eckstein FS, Bonilla LF, Englberger L, Immer FF, Berg TA, Schmidli J, et al. The St. Jude Medical symmetry aortic connector system for proximal vein graft anastomoses in coronary artery bypass grafting. J Thorac Cardiovasc Surg
2002;123:777–82.[Abstract/Free Full Text]
- Hornik L, Tenderich G, Minami K, Fassbender D, Schulz TO, Beinert B, et al. First experience with the St. Jude Medical, Inc, symmetry bypass system (aortic connector system). J Thorac Cardiovasc Surg
2003;125:414–7.[Free Full Text]
- Endo M, Benhameid O, Morin JF, Shennib H. Avoiding aortic clamping during coronary artery bypass using an automated anastomotic device. Ann Thorac Surg
2002;73:1000–1.[Abstract/Free Full Text]
- Eckstein FS, Bonilla LF, Englberger L, Stauffer E, Berg TA, Schmidli J, et al. Minimizing aortic manipulation during OPCAB using the symmetry aortic connector system for proximal vein graft anastomoses. Ann Thorac Surg
2001;72:S995–8.[Abstract/Free Full Text]
- Donsky AS, Schussler JM, Donsky MS, Roberts WC, Hamman BL. Thrombotic occlusion of the aortic ostia of saphenous venous grafts early after coronary artery bypass grafting by using the symmetry aortic connector system. J Thorac Cardiovasc Surg
2002;124:397–9.[Free Full Text]
- Antona C, Scrofani R, Lemma M, Vanelli P, Mangini A, Danna P, et al. Assessment of an aortosaphenous vein graft anastomotic device in coronary surgery: clinical experience and early angiographic results. Ann Thorac Surg
2002;74:2101–5.[Abstract/Free Full Text]
- Wiklund L, Bugge M, Berglin E. Angiographic results after the use of a sutureless aortic connector for proximal vein graft anastomoses. Ann Thorac Surg
2002;73:1993–4.[Abstract/Free Full Text]
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ABSTRACT
INTRODUCTION
