ATS
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

This Article
Right arrow Abstract Freely available
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to Personal Folders
Right arrow Download to citation manager
Right arrow Author home page(s):
Akihiko Usui
Yuichi Ueda
Right arrow Permission Requests
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Hagiwara, H.
Right arrow Articles by Ueda, Y.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Hagiwara, H.
Right arrow Articles by Ueda, Y.
Related Collections
Right arrow Coronary disease

Ann Thorac Surg 2004;77:805-810
© 2004 The Society of Thoracic Surgeons

Original article: cardiovascular

Mid-term structural change in the radial artery grafts after coronary artery bypass grafting

Hiroaki Hagiwara, MDa*, Toshiaki Ito, MDb, Haruo Kamiya, MDc, Toshiaki Akita, MDa, Akihiko Usui, MDa, Yuichi Ueda, MDa

a Nagoya University Graduate School of Medicine, Department of Cardiothoracic Surgery, Japanese Red Cross Nagoya First Hospital, Aichi, Japan
b Department of Cardiovascular Surgery, 3-35 Michishita-cho, Nakamura-ku, Nagoya-shi, Aichi, Japan
c Cardiovascular Medicine, Aichi, Japan

Accepted for publication September 8, 2003.

* Address reprint requests to Dr Hagiwara, Nagoya University Graduate School of Medicine, Department of Cardiothoracic Surgery, 65 Tsurumai-cho, Showa-ku, Nagoya-shi, Aichi, 466-8550 Japan
e-mail: hiroakih{at}med.nagoya-u.ac.jp


   Abstract
Top
 Abstract
Introduction
 Patients and methods
 Results
 Comment
 Acknowledgments
 References
 
BACKGROUND: Currently, excellent patency rates of radial artery grafts for coronary artery bypass grafting in the early period have been reported. However, the long-term result of radial artery grafts remains unclear. We investigated the midterm structural change in radial artery grafts using intravascular ultrasound imaging (IVUS).

METHODS: IVUS studies were performed on 15 radial artery grafts in the early phase and 11 in the midterm phase (20.3 ± 13.7 days and 37.6 ± 7.2 months after surgery, respectively). The radial artery grafts were observed throughout the entire length and 10 cross-sectional images were selected from each graft for measurement of the thickness of the intima (IN) and intima-plus-media (IN + MD). Grafts having palpable arteriosclerosis at the time of harvesting were excluded. IN and IN + MD were compared between the early and midterm phases using repeated measures analysis of variance. The coefficient of variation of IN and IN + MD was calculated as an index of irregularity and compared between the phases.

RESULTS: IVUS revealed uniform and thin intima and media in the early and midterm groups and IVUS images were similar between the groups. There was no significant difference in both IN and IN + MD between the groups (IN, p = 0.83; IN + MD, p = 0.55). The median of coefficient of variation of IN and IN + MD was 8.5% and 8.1% in the early group and 8.7% and 9.3% in the midterm group. Again, there was no significant difference between the groups (IN, p = 0.87; IN + MD, p = 0.27).

CONCLUSIONS: The present study suggested that structural changes rarely developed in radial artery grafts over several years after surgery.


   Introduction
Top
 Abstract
 Introduction
Patients and methods
 Results
 Comment
 Acknowledgments
 References
 
Early results of coronary artery bypass grafting (CABG) using radial artery grafts are excellent [1–3], but it is still controversial whether radial artery grafts are superior to saphenous vein grafts (SVGs) in the late phase.

It has been reported that saphenous veins used as aortocoronary conduits are apt to develop intimal hyperplasia, followed by atheromatous change. This characteristic has been proved histologically and is responsible for the poor long-term results [4]. Kalan and colleagues [5] reported that most SVGs had developed narrowing of cross-sectional area caused by plaque when investigated histologically more than 1 year after CABG.

Radial artery grafts have recently been reappraised as alternatives to SVGs. These grafts have a high propensity to demonstrate string sign when anastomosed to the coronary arteries with subcritical stenosis [6, 7]. This characteristic led surgeons to use radial artery grafts to revascularize vessels with severe stenosis. With this strategy, the patency rate of radial artery grafts is satisfying in the early period [8]. But it has not been clarified whether radial artery grafts maintain their original structure in the long-term period after implantation.

The purpose of this study was to determine whether radial artery grafts developed structural change in the wall in the midterm phase after surgery. We investigated radial artery grafts with intravascular ultrasound imaging (IVUS) in the early and the midterm patients and compared the wall structure.


   Patients and methods
Top
 Abstract
 Introduction
 Patients and methods
Results
 Comment
 Acknowledgments
 References
 
Two hundred forty-nine patients received CABG with radial artery grafts by a single surgeon (T.I.) in our institute from August 1997 to April 2002. Radial arteries have been applied for revascularization of coronary arteries with severe stenosis to avoid competitive flow. Radial artery grafts were used in patients without positive Allen's test or renal failure. The patency rate of the radial artery grafts was 97.2% in angiographic studies performed in the early period.

Intravascular ultrasound imaging study was performed on patients who met the following criteria, after obtaining their written informed consent: (1) the radial artery graft was anastomosed directly to the ascending aorta; and (2) angiographic study revealed patency of the radial artery graft in the early phase after surgery.

Intravascular ultrasound imaging study was performed during the same hospitalization after surgery in 19 patients, but complete measurements were obtained in only 15 patients due to probe insertion difficulty or graft flexion. IVUS findings of these 15 patients were evaluated as the early-term findings (early group).

Intravascular ultrasound imaging study was also performed in another 15 patients who were followed for more than 2 years. Complete studies were achieved in only 11 of these patients due to technical difficulty. The average period from surgery to the IVUS studies was 37.6 ± 7.2 months, ranging from 27 to 46 months. The IVUS findings of these 11 patients were evaluated as the midterm findings (midterm group).

There were no significant differences between the groups in age, gender, risk factors, past myocardial infarction, left main trunk lesion, ejection fraction, or anastomosed sites of radial artery grafts (Table 1).


View this table:
[in this window]
[in a new window]
  		Table 1. Patient Characteristics

 
Surgical technique
Radial artery grafts were harvested from nondominant forearms. A straight incision was made over the course of the artery, and the fascia was incised and the artery was exposed. Branch arteries were clipped with metal clips. After heparinization, the distal end was divided and papaverine hydrochloride solution (1 mg/mL) was injected. The distal end was clamped and systemic pressure was applied to the graft until use. Distal anastomosis was performed in end to side fashion with 7-0 polypropylene running suture. Proximal anastomosis to the ascending aorta was done with 5-0 polypropylene running suture. Continuous intravenous infusion of diltiazem (0.5 µg · kg-1 · min-1) was given throughout the perioperative period and continued until replacement with oral medication of Ca channel blockers.

Angiographic and IVUS studies
Intravascular ultrasound imaging study was performed with an In-Vision (Jomed Inc, Rancho Cordova, CA) and a 20-MHz solid-state 64-element imaging catheter (Avanar F/X, Jomed Inc). The imaging catheter was automatically pulled back by an auto pullback device (Trak Back II, Jomed Inc), which provides accurate length measurement. The findings obtained with IVUS system were analyzed by an In-Vision Dicom Viewer (Jomed Inc).

After angiographic study, the radial artery grafts were observed with IVUS along the entire length from the distal to the proximal anastomosis. Ten cross-sectional images were obtained at regular intervals from each graft and the wall structure of grafts was observed. In almost all cross-sectional images, there was a characteristic three-layer appearance: an inner echodense layer, a middle echolucent layer, and an outer echodense layer. It is generally accepted that the inner echodense layer corresponds to the intima of the artery and the middle echolucent layer to the media [9–11]. The thickness of the inner layer (IN) and that of the inner-plus-middle layer (IN + MD) was measured at the farthest site of the ultrasound probe in each 10 cross-sectional image.

Comparison between the early group and mid-term group
Based on the operative findings, the radial arteries were classified into two types: nonsclerotic grafts and atherosclerotic grafts. When the radial artery had palpable atherosclerotic change at the time of harvesting, it was classified as an atherosclerotic graft and stenosis was ruled out with a 2-mm probe before use. There were 13 nonsclerotic grafts in the early group and 9 in the midterm group, and 2 atherosclerotic grafts in each of the groups.

To determine the structural difference between the early group and the midterm group, we compared the IVUS findings with the exclusion of the atherosclerotic grafts. IN and IN + MD were compared between the two groups, using repeated measures analyses of variance (ANOVA).

The irregularity of the wall thickness was evaluated as the intrapatient coefficient of variation of IN and IN + MD. These values were calculated with the following equation:

Statistical analysis
All statistical analyses were performed using SAS release 8.2 software (Cary, NC). Continuous data are presented as mean ± standard deviation (SD). Nominal data were analyzed by Fischer's exact test. The least squares means of IN and IN + MD were estimated using the MIXED procedure. The IN and IN + MD were presented as the least squares means ± standard error; IN and IN + MD were compared between the early group and the midterm group, respectively, using repeated measures ANOVA. The intrapatient coefficient of variation of IN and IN + MD were also compared between the two groups, respectively, using the Mann-Whitney U test. A p value less than 0.05 was considered significant.


   Results
Top
 Abstract
 Introduction
 Patients and methods
 Results
Comment
 Acknowledgments
 References
 
Good quality ultrasound images were obtained in all 15 grafts in the early group (13 nonsclerotic grafts and 2 atherosclerotic grafts), and in all 11 in the midterm group (9 nonsclerotic grafts and 2 atherosclerotic grafts).

Nonsclerotic grafts
The angiographic studies demonstrated the patency of all 13 grafts in the early group. Twelve of 13 grafts were perfectly patent but one radial artery graft showed narrowing due to graft kinking. IVUS revealed uniform and thin intima and media over the entire length in all grafts with the exception of the site of graft kinking. A representative cross-sectional image is demonstrated in Figure 1.



View larger version (132K):
[in this window]
[in a new window]
  		Fig 1. The IVUS imaging of a radial artery graft in the early phase. IVUS study was performed 17 days after coronary artery bypass grafting. IVUS demonstrated a characteristic three-layer appearance as follows: (A) the inner echodense layer corresponds to the arterial intima; (B) the middle echolucent layer to the media and the outer echodense layer to the adventitia and surrounding tissue; (C) the inner echolucent area to the arterial lumen in which the echo probe and ring down phenomenon of the probe are demonstrated. (A) The thickness of the inner echodense layer is thin and uniform throughout the entire length. (IVUS = intravascular ultrasound imaging.)

 
All 9 grafts in the midterm group were patent. The angiographic studies demonstrated perfect patency in 8 grafts, but revealed 90% stenosis in one, which was not detected in the early angiography. A clear image was not obtained at the stenotic site because the lumen was so narrow that we could not locate the internal surface within the focal area of the ultrasound probe. We could not identify the pathology of this region and the cross-sectional image for measurement was not obtained at this site. However, complete observation could be performed at other sites of this graft and all sites of the remaining 8 grafts, and IVUS showed uniform and thin intima and media at these sites. A representative cross-sectional image is illustrated in Figure 2, which is similar to Figure 1.



View larger version (123K):
[in this window]
[in a new window]
  		Fig 2. The IVUS imaging of a radial artery graft in the mid-term phase. The radial artery graft was implanted 27 months previously. IVUS demonstrated thin and uniform thickness of the inner echodense layer (intima [A]). There was no evidence of intimal hyperplasia. This finding is similar to that of the early phase (Fig 1). (B) Indicates the middle echolucent layer (media); (C) indicates the echo probe and ring down phenomenon. (IVUS = intravascular ultrasound imaging.)

 
In the repeated ANOVA, 1 patient with incomplete graft data was excluded. No significant difference was seen in either IN or IN + MD between the early group and the midterm group (IN, p = 0.83; IN + MD, p = 0.55).

The median and range of the intrapatient coefficient of variation are shown in Table 2. In both IN and IN + MD, no significant difference was seen in the coefficient of variation between the early group and the midterm group (IN, p = 0.87; IN + MD, p = 0.27).


View this table:
[in this window]
[in a new window]
  		Table 2. Comparison Between Early and Mid-Term Groups

 
Atherosclerotic grafts
Two grafts each in the early and midterm groups had palpable sclerotic change at the time of harvesting. The angiographic studies demonstrated perfect patency of these four grafts but IVUS revealed thickening and hyperechoic spots in the inner layers. Representative images of the grafts in the early and midterm groups are demonstrated in Figures 3 and 4, respectively. IVUS did not detect stenosis or unstable plaque in the grafts in either group.



View larger version (122K):
[in this window]
[in a new window]
  		Fig 3. The IVUS imaging of a radial artery graft in the early phase having palpable arteriosclerosis at the time of harvesting. IVUS study was performed in the early phase after operation. IVUS reveals irregular thickening of the inner echodense layer (intima). The intima is relatively thin at one site (A), but it has thickened at another site (A'). These findings represent the atherosclerotic change of the conduit. (B) Indicates the middle echolucent layer (media); (C) indicates the echo probe and ring down phenomenon. (IVUS = intravascular ultrasound imaging.)

 


View larger version (123K):
[in this window]
[in a new window]
  		Fig 4. The IVUS imaging of a radial artery graft in the mid-term phase having palpable arteriosclerosis at the time of harvesting. IVUS study was performed 28 months after operation. The two large arrows facing in opposite direction (A) designate the inner echodense layer (intima). It is obviously thicker and more highly echoic than the findings in Figures 1 or 2. However, the intimal surface is smooth and IVUS study did not detect either stenosis or protruding plaque. Small arrowsdesignate the intimal surface. Another large arrow (B) indicates the media. (IVUS = intravascular ultrasound imaging.)

 
Comparison between radial artery graft and SVG
One patient in the mid-term group had both a radial artery graft and SVG. This patient had undergone CABG 45 months previously. These grafts were observed with IVUS and the wall structure was compared. The representative cross-sectional images are illustrated in Figures 5 and 6. The SVG had developed protruding plaque and such atheromatous changes were observed in every cross-sectional area, while the radial artery graft had smooth, uniform and thin intima and media throughout the entire length.



View larger version (125K):
[in this window]
[in a new window]
  		Fig 5. The IVUS finding of a radial artery of a patient who has both a radial artery graft and a saphenous vein graft. The patient underwent coronary artery bypass grafting 45 months previously. IVUS study revealed thin and uniform thickness of the inner echodense layer (intima [A]) and the middle echolucent layer (media [B]). There is no evidence of atherosclerotic change. (C) Indicates the echo probe and ring down phenomenon; (D) indicates the artifact; small arrows designate the intimal surface. (IVUS = intravascular ultrasound imaging.)

 


View larger version (117K):
[in this window]
[in a new window]
  		Fig 6. The IVUS finding of a saphenous vein graft of the same patient as in Figure 5. Small arrows indicate the internal surface of the conduit; large arrows indicate a protruding plaque. In contrast with the radial artery graft illustrated in Figure 5, the internal surface is irregular and protruding plaque is observed in every cross-sectional image. These findings characterize atherosclerotic changes of this conduit. (IVUS = intravascular ultrasound imaging.)

 

   Comment
Top
 Abstract
 Introduction
 Patients and methods
 Results
 Comment
Acknowledgments
 References
 
Radial arteries have been widely applied as conduits for CABG, because they were reappraised by Acar and colleagues [12]. Currently, radial artery grafts demonstrate excellent early results thanks to technical improvements and a better understanding the characteristics of the grafts [8, 13]. However it is still unclear whether radial artery grafts are superior to SVG in the late phase.

Most SVGs develop atheromatous changes in the wall after implantation, and there is no way to prevent these degenerative changes. Therefore, it seems problematic to use these conduits to revascularize important vessels in young patients. There was a patient having both a radial artery graft and a SVG in our mid-term group. IVUS study was performed on these grafts 45 months after surgery. The SVG had developed intimal hyperplasia and protruding plaque was observed at every site of this graft. It is possible that these atheromatous changes will progress and result in graft occlusion. In contrast, the radial artery graft had smooth, uniform and thin intima and media throughout the entire length. The radial artery graft had developed much less atheromatous change than the SVG.

In order to assess the structural change of radial artery grafts, we compared the radial artery grafts of an early group with that of a mid-term group. Most radial arteries had no palpable athrosclerosis at the time of harvesting. IVUS images of such grafts showed similar findings between the early and mid-term group. The coefficient of variation of IN and IN + MD as an index of irregularity were also similar between the two groups. These findings indicate that radial artery grafts rarely develop degenerative change in the wall over several years.

The angiography detected a new 90% stenosis in one radial artery graft in the mid-term group. This lesion was not noted in the early angiography. We could not clarify the cause of the stenosis. As the lesion was localized and other sites of this graft showed no degenerative change, we speculated that the stenosis may have been due to graft spasm or intraoperative injury. Possati and colleagues demonstrated that perfectly patent radial artery grafts remain patent in the mid-term period [14]. We thus consider it to be an infrequent occurrence that patent radial artery grafts will develop stenosis in the mid-term period unless affected by flow competition. This lesion was successfully treated by percutaneous transluminal coronary angioplasty.

Two grafts each in the early and mid-term groups were recorded on the chart to have palpable arteriosclerosis at the time of harvesting. The IVUS studies demonstrated intimal hyperplasia of these grafts. It is uncertain whether the hyperplasia of the grafts in the mid-term group had progressed or not, as these grafts were not investigated with IVUS in the early phase. However, the IVUS studies demonstrated neither stenosis nor protruding plaque in these grafts. The internal surface was smooth in contrast with the SVG in Figure 6; therefore, these radial artery grafts may be superior to the SVGs in the late phase. However, it remains unclear whether atherosclerotic radial artery grafts are suitable for CABG conduits. Close follow-up is necessary for such grafts.

Limitations of the study
There were some technical difficulties in performing the IVUS. Complete investigation was achieved in only 76% of patients in the present study. However, the IVUS findings provided accurate information about the graft wall, and this is the only method that can be used in vivo to evaluate the wall structure of the grafts.

The small number of patients and short follow-up period are other limitations of this study. Our findings strongly indicate the superiority of radial artery graft to saphenous vein graft in the longer term, but a prospective randomized longer term study in larger groups is necessary to confirm our conclusion.

Conclusions
In conclusion, the present study suggested that radial artery grafts without atherosclerotic change at the time of harvesting rarely developed structural change over several years. Therefore, we believe that radial artery grafts should provide a better patency rate than SVGs in the late phase after surgery. However, proper preparation and selection of the radial artery grafts, correct surgical indication to avoid competitive flow, and antispastic therapy are essential to achieve good results with radial artery grafts [15, 16].


   Acknowledgments
Top
 Abstract
 Introduction
 Patients and methods
 Results
 Comment
 Acknowledgments
References
 
We are grateful to Dr Masahiko Ando for his generous assistance with the statistical analysis.


   References
Top
 Abstract
 Introduction
 Patients and methods
 Results
 Comment
 Acknowledgments
 References
 

  1. Dietl C.A., Benoit C.H. Radial artery graft for coronary revascularization: technical considerations. Ann Thorac Surg 1995;60:102-110.[Abstract/Free Full Text]
  2. da Costa F.D., da Costa I.A., Poffo R., et al. Myocardial revascularization with the radial artery: a clinical and angiographic study. Ann Thorac Surg 1996;62:475-480.[Abstract/Free Full Text]
  3. Chen A.H., Nakao T., Brodman R.F., et al. Early postoperative angiographic assessment of radial grafts used for coronary artery bypass grafting. J Thorac Cardiovasc Surg 1996;111:1208-1212.[Abstract/Free Full Text]
  4. Walts A.E., Fishbein M.C., Matloff J.M. Thrombosed, ruptured atheromatous plaques in saphenous vein coronary artery bypass grafts: ten years' experience. Am Heart J 1987;114(4 Pt 1):718-723.[Medline]
  5. Kalan J.M., Roberts W.C. Morphologic findings in saphenous veins used as coronary arterial bypass conduits for longer than 1 year: necropsy analysis of 53 patients, 123 saphenous veins, and 1,865 five-millimeter segments of veins. Am Heart J 1990;119:1164-1184.[Medline]
  6. Maniar H.S., Sundt T.M., Barner H.B., et al. Effect of target stenosis and location on radial artery graft patency. J Thorac Cardiovasc Surg 2002;123:45-52.[Abstract/Free Full Text]
  7. Acar C., Ramsheyi A., Pagny J.Y., et al. The radial artery for coronary artery bypass grafting: clinical and angiographic results at five years. J Thorac Cardiovasc Surg 1998;116:981-989.[Abstract/Free Full Text]
  8. Iaco A.L., Teodori G., Di Giammarco G., et al. Radial artery for myocardial revascularization: long-term clinical and angiographic results. Ann Thorac Surg 2001;72:464-469.[Abstract/Free Full Text]
  9. Maheswaran B., Leung C.Y., Gutfinger D.E., et al. Intravascular ultrasound appearance of normal and mildly diseased coronary arteries: correlation with histologic specimens. Am Heart J 1995;130:976-986.[Medline]
  10. Siegel R.J., Chae J.S., Maurer G., et al. Histopathologic correlation of the three-layered intravascular ultrasound appearance of normal adult human muscular arteries. Am Heart J 1993;126:872-878.[Medline]
  11. Gussenhoven E.J., Essed C.E., Lancee C.T., et al. Arterial wall characteristics determined by intravascular ultrasound imaging: an in vitro study. J Am Coll Cardiol 1989;14:947-952.[Abstract]
  12. Acar C., Jebara V.A., Portoghese M., et al. Revival of the radial artery for coronary artery bypass grafting. Ann Thorac Surg 1992;54:652-660.[Abstract]
  13. Amano A., Hirose H., Takahashi A., Nagano N. Coronary artery bypass grafting using the radial artery: mid-term results in a Japanese institute. Ann Thorac Surg 2001;72:120-125.[Abstract/Free Full Text]
  14. Possati G., Gaudino M., Alessandrini F., et al. Midterm clinical and angiographic results of radial artery grafts used for myocardial revascularization. J Thorac Cardiovasc Surg 1998;116:1015-1021.[Abstract/Free Full Text]
  15. Barner H.B. Remodeling of arterial conduits in coronary grafting. Ann Thorac Surg 2002;73:1341-1345.[Abstract/Free Full Text]
  16. He G.W. Arterial grafts for coronary artery bypass grafting: biological characteristics, functional classification, and clinical choice. Ann Thorac Surg 1999;67:277-284.[Abstract/Free Full Text]



This article has been cited by other articles:


Home page
 Eur. J. Cardiothorac. Surg.Home page
S. M. Wildhirt, B. Voss, F. von Canal, M. Benz, J. B. Grammer, R. Bauernschmitt, P. Tassani, and R. Lange
Graft function, histopathology and morphometry of radial arteries used as conduits for myocardial revascularization in patients beyond age 70.
Eur. J. Cardiothorac. Surg., August 1, 2006; 30(2): 333 - 340.
[Abstract] [Full Text] [PDF]

Home page
 Ann. Thorac. Surg.Home page
L. R. Sajja, G. Mannam, N. R. Pantula, and S. Sompalli
Role of Radial Artery Graft in Coronary Artery Bypass Grafting
Ann. Thorac. Surg., June 1, 2005; 79(6): 2180 - 2188.
[Abstract] [Full Text] [PDF]

Home page
 CirculationHome page
C. Acar, R. C. Cook, S. G. Raja, S. Hashim, I. Birdi, P. J. Shah, R. A. Baker, J. J. Knight, U. N. Khot, D. T. Friedman, et al.
Letters Regarding Article by Khot et al, "Radial Artery Bypass Grafts Have an Increased Occurrence of Angiographically Severe Stenosis and Occlusion Compared With Left Internal Mammary Arteries and Saphenous Vein Grafts" * Letters Regarding Article by Khot et al, "Radial Artery Bypass Grafts Have an Increased Occurrence of Angiographically Severe Stenosis and Occlusion Compared With Left Internal Mammary Arteries and Saphenous Vein Grafts" * Letters Regarding Article by Khot et al, "Radial Artery Bypass Grafts Have an Increased Occurrence of Angiographically Severe Stenosis and Occlusion Compared With Left Internal Mammary Arteries and Saphenous Vein Grafts" * Letters Regarding Article by Khot et al, "Radial Artery Bypass Grafts Have an Increased Occurrence of Angiographically Severe Stenosis and Occlusion Compared With Left Internal Mammary Arteries and Saphenous Vein Grafts" * Response
Circulation, January 4, 2005; 111(1): e6 - e9.
[Full Text] [PDF]

Home page
 Ann. Thorac. Surg.Home page
S. M. Wildhirt
INVITED COMMENTARY
Ann. Thorac. Surg., November 1, 2004; 78(5): 1621 - 1622.
[Full Text] [PDF]

This Article
Right arrow Abstract Freely available
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to Personal Folders
Right arrow Download to citation manager
Right arrow Author home page(s):
Akihiko Usui
Yuichi Ueda
Right arrow Permission Requests
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Hagiwara, H.
Right arrow Articles by Ueda, Y.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Hagiwara, H.
Right arrow Articles by Ueda, Y.
Related Collections
Right arrow Coronary disease

HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
ANN THORAC SURG ASIAN CARDIOVASC THORAC ANN EUR J CARDIOTHORAC SURG
J THORAC CARDIOVASC SURG ICVTS ALL CTSNet JOURNALS