| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
J Thorac Cardiovasc Surg 2004;127:142-148
© 2004 The American Association for Thoracic Surgery
Surgery for acquired cardiovascular disease |
a Department of Thoracic and Cardiovascular Surgery, The Cleveland Clinic Foundation, Cleveland, Ohio, USA
b Department of Biostatistics and Epidemiology, The Cleveland Clinic Foundation, Cleveland, Ohio, USA
Read at the Twenty-eighth Annual Meeting of The Western Thoracic Surgical Association, Carlsbad, Calif, June 18-21, 2003.
Received for publication June 17, 2003; revisions received August 8, 2003; accepted for publication August 13, 2003.
* Address for reprints: Joseph F. Sabik, MD, Department of Thoracic and Cardiovascular Surgery, The Cleveland Clinic Foundation/Desk F24, 9500 Euclid Avenue, Cleveland, OH 44195, USA
sabikj{at}ccf.org
 |
Abstract |
|---|
 Top Abstract Patients and methodsResultsDiscussionSummaryReferences |
|---|
METHODS: From January 1997 to July 2000, 481 patients underwent off-pump coronary artery bypass grafting and 3231 underwent on-pump coronary artery bypass grafting. Propensity matching was used to match 406 patients from each group. Previously, the propensity-matched off-pump patients were found to have had significantly fewer bypass grafts. These 812 patients were followed for time-related events, including death, myocardial infarction, percutaneous coronary intervention, coronary reoperation, and the combined end point of all-cause mortality, myocardial infarction, and all coronary reintervention. Follow-up was 95% complete.
RESULTS: At 4 years, survival was 87.5% after off-pump and 91.2% after on-pump coronary artery bypass grafting (P = .2); freedom from myocardial infarction was 92.6% and 95.7% (P = .7), respectively; freedom from percutaneous coronary intervention was 94.3% and 95.5% (P = .9), respectively; freedom from coronary reoperation was 98.1% and 99.0% (P = .4), respectively; and freedom from the combined end point of all-cause mortality, myocardial infarction, and coronary reintervention was 75.2% and 82.9% (P = .14), respectively.
CONCLUSIONS: Off-pump and on-pump coronary artery bypass grafting results in equivalent midterm outcomes. Fewer bypass grafts in the off-pump patients did not decrease survival or increase ischemic events at 4 years.
|
Patients and methods |
|---|
|
TopAbstractPatients and methodsResultsDiscussionSummaryReferences |
|---|
At the discretion of the surgeon, myocardial revascularization was performed off-pump in 481 patients and on-pump in 3231. Our technique of on- and off-pump surgery has been previously described.1 On- and off-pump patients were contemporaneous and not sequential groups. Patients who were converted from off-pump to on-pump (n = 15) were included in the off-pump group.
To reduce the influence of selection bias on the comparison of outcome, patients were selected for this study using propensity score pair-wise matching of off-pump to on-pump patients. Our method has been described previously.1 Using this technique, 406 off-pump patients were matched to 406 on-pump patients. These 812 patients make up the study group. Preoperative characteristics, including extent and distribution of coronary artery disease and left ventricular function, were well matched in the two groups (Table 1). However, off-pump patients had more peripheral vascular disease and history of stroke and were somewhat less symptomatic. These were the only dissimilar preoperative characteristics (P < .05) among 70 examined.
|
Hospital death (1.0% vs. 0.5%, P = .7), stroke (1.2% vs. 0.7%, P = .7), and myocardial infarction (1.2% vs. 0.7%, P = .7) were similar in the on- and off-pump patients. However, off-pump patients experienced less encephalopathy (1.7% vs. 0%, P = .02), renal failure requiring dialysis (1.5% vs. 0%, P = .03), red blood cell usage (53% vs. 42%, P = .002), and fewer sternal wound infections (2.0% vs. 0.2%, P = .04).
Follow-up
Of the 812 propensity-matched patients, there were 806 hospital survivors. They were followed up by mail and/or telephone interview. Follow-up was 95% complete. Median follow-up of all hospital survivors was 3.2 years (mean 2.9 ± 1.6 years) with a range of 1 week to 5.7 years. For patients who underwent on-pump surgery, median follow-up was 3.8 years (mean 3.4 ± 1.8 years) with a range of 1 week to 5.7 years, and for patients who underwent off-pump surgery, median follow-up was 2.6 years (mean 2.4 ± 1.3 years) with a range of 1 week to 5.3 years.
Statistical analyses
Descriptive summaries are presented as frequencies and percentages for categorical data, and as means and standard deviations for continuous variables. Unless otherwise specified, group comparisons were made using chi-square tests.
Time-related outcome events used to compare off-pump with on-pump CABG were (1) death from any cause, including hospital death, (2) myocardial infarction, (3) percutaneous coronary intervention, (4) coronary reoperation, and (5) the combined end point of all-cause mortality, myocardial infarction, and all coronary reintervention, defined as percutaneous coronary intervention and coronary reoperation. Time-related estimates were generated using the Kaplan-Meier method and comparisons made using the log-rank statistic. Numbers of patients at risk at 1, 2, 3, and 4 years were 322, 306, 151, and 21 in the off-pump group and 325, 311, 276, and 174 in the on-pump group, respectively.
|
Results |
|---|
|
TopAbstractPatients and methodsResultsDiscussionSummaryReferences |
|---|
|
|
|
|
|
|
Discussion |
|---|
|
TopAbstractPatients and methodsResultsDiscussionSummaryReferences |
|---|
Although much has been published on the hospital results of patients undergoing off-pump CABG, little has been reported on late outcomes. Gundry and colleagues first reported late results of off-pump myocardial revascularization, comparing 7-year outcomes of 219 unmatched off-pump and on-pump patients.11 They found that the groups had similar survival. However, there was a threefold increase in need for coronary reintervention in the off-pump patients. A total of 30% of the off-pump patients underwent catheterization for recurrent symptoms and 20% had either repeat coronary surgery or percutaneous intervention, whereas only 16% of the on-pump patients underwent angiography for symptoms and 7% had repeat coronary surgery or percutaneous intervention.
Like Gundry, we found similar late survival in the off-pump and on-pump surgery patients. However, we did not identify more coronary reinterventions in the off-pump group. This difference may be due to the Gundry study being performed prior to the invention and adoption of the technology of coronary artery stabilization and exposure that has facilitated off-pump coronary revascularization. Supporting this assumption is the fact that in their off-pump patients, the majority of percutaneous interventions were performed on coronary arteries that had been previously bypassed. If effective devices for coronary artery stabilization had been available, many of these procedures may not have been necessary. The beneficial effect of coronary artery stabilization in off-pump surgery on bypass graft patency has been clearly demonstrated.13
In more contemporary studies, Beating Heart Against Cardioplegic Arrest Study (BHACAS) 1 and 2, Angelini and colleagues reported similar midterm outcomes in patients randomized to either off-pump or on-pump CABG.10 At 29.3 ± 7.4 months and 15.7 ± 5.5 months for BHACAS 1 and 2, respectively, there were no differences in mortality, cardiac-related events, or need for further coronary reintervention in the two groups. Although these patients have not been followed as long as ours, the findings are similar.
Surprisingly in our study, despite more incomplete revascularization in the off-pump patients, this group did not experience more late ischemia-related events than patients in the on-pump group. In previous studies, incomplete revascularization has been found to be associated with worse outcomes.14-16 In a recent report, Arom and colleagues found more recurrence of angina and repeat coronary interventions at 1 year in patients who underwent off-pump CABG than in those who had surgery with the assistance of cardiopulmonary bypass.12 Although they did not report completeness of revascularization, their off-pump patients received fewer bypass grafts than their on-pump patients.12
Although there may be several reasons why incomplete revascularization did not affect late outcomes in this study, we believe two are likely possibilities. The first may be how we defined incomplete revascularization. Incomplete revascularization was not defined as the difference between what the surgeon intended to graft prior to starting the operation and what was actually done; rather, it was defined as lack of grafting any coronary artery system with 50% or more stenosis or failure to graft both the LAD and circumflex systems for 50% or more left main trunk disease.1 To determine why patients were incompletely revascularized, operative notes were carefully reviewed. When we were able to determine the reason for incomplete revascularization, patients were distributed similarly in the on- and off-pump groups. However, there were many more patients in the off-pump group for whom no reason for incomplete revascularization was given in the operative notes. This suggests that the surgeon did not intend to graft this area and thus believed grafting this area of the myocardium to be unnecessary. Second, detrimental effects of incomplete revascularization increase with time, and patients in this study may not have been followed long enough for differences to emerge.16
Limitations
This study was a clinical review of patients who underwent off-pump and on-pump primary CABG. Patients were not randomly assigned to either group, but instead the choice of procedure was made by the surgeon at the time of operation. Therefore, selection bias may affect our findings. To reduce the effect of selection bias on outcomes, we used propensity matching to identify well-matched off-pump and on-pump patients for comparison. In fact, the off-pump and on-pump groups were well matched in 67 of 70 evaluated preoperative characteristics.
|
Summary |
|---|
|
TopAbstractPatients and methodsResultsDiscussionSummaryReferences |
|---|
Discussion
Dr Robbin Cohen (Los Angeles, Calif). You report midterm results including 5-year follow-up of 406 off-pump bypass operations, which were compared with a group of propensity-matched pairs of the same size who underwent on-pump operations. I appreciated that you noted the fact that the perioperative results were originally reported at the 81st annual meeting of The American Association for Thoracic Surgery and subsequently published in The Journal of Thoracic and Cardiovascular Surgery in 2002. It is important to note that in that report there were improvements in encephalopathy, sternal infections, blood use, and renal failure requiring dialysis. Unlike other reports at the same time, there was no difference between the off-pump and the on-pump groups in perioperative mortality, stroke, myocardial infarction, and reoperation for bleeding.
The current report gives some of the longest follow-up to date comparing on- with off-pump coronary surgery and shows the results in both groups to be excellent and equivalent. This is extremely important and reassuring in that it indicates that excellent long-term results can be obtained with off-pump coronary surgery when compared with the traditional model. At the same time, as a proponent of off-pump surgery, it is hard not to be at least a little disappointed that the results in the off-pump group weren't significantly better, and it bothers me that this seems to be something that is becoming more and more difficult to prove, at least more difficult to prove than we thought it would be. That is the basis for most of my questions.
In your study, fewer grafts per patient were performed in the off-pump group, which leads one to believe that many of the patients were incompletely revascularized, despite the fact that you showed very clearly that not only the severity but the extent of coronary disease seemed to be similar by statistical analysis. The only conclusion that I can make is that complete revascularization, something that we have held fairly dearly, is overrated. What do you think about that and how do your results explain that?
Dr Sabik. Thank you for your kind remarks. We were also concerned about the amount of incomplete revascularization in the off-pump patients, and this is one of the reasons we decided to do this study. Our expectations were that we would find more ischemic events in the off-pump patients and that these would be associated with incomplete revascularization. We were surprised when we did not find this. To examine incomplete revascularization more closely, I reviewed the operative notes of all patients who were incompletely revascularized and determined why this was so. We defined incomplete revascularization as lack of a bypass graft to any of the 3 coronary systems (LAD, circumflex, and right coronary artery) when there was a 50% or greater stenosis in that system, or when a patient had a 50% or greater left main stenosis and no bypass grafts to the LAD and circumflex. In reviewing the operative notes of the incompletely revascularized patients, I found that when the reason for incomplete revascularization was stated, such as the coronary was too small or the area was infarcted and scarred, the percentages in each group were similar. What differed was that in the off-pump group, there were more patients for whom no reason was given as to why an artery was grafted. I believe that in these cases, the surgeons’ intention was not to bypass that artery, and therefore they felt it was not necessary to graft these arteries. Perhaps this is why we did not find incomplete revascularization to be associated with an increase in ischemic events.
Dr Cohen. This is a very elegant statistical analysis by 1 of our most respected statisticians, yet it is retrospective and the inclusion criterion for the study was basically surgeon preference. Have you done anything to determine which subgroups of patients in your analysis actually stand to gain the most by having their coronary operations performed off-pump? How has that affected the current indications for off-pump coronary bypass grafting at the Cleveland Clinic?
Dr Sabik. The problem with trying to answer that question is that there were too few events in this group of patients. In the 406 off-pump patients, there were only 2 deaths, 3 strokes, and 3 perioperative myocardial infarctions. To do a multivariable analysis and identify who benefits, we need many more events. At the Clinic, the decision to operate on- or off-pump still is based on surgeon preference. I can tell you my approach. I believe that morbidity is reduced by performing coronary surgery off-pump; so long as I can perform the same operation on- or off-pump, I perform off-pump surgery.
Dr Cohen. Finally, there have been considerable advances in technology and surgical technique since you undertook your original study, which was probably in the early to mid-1990s. All of these are designed to facilitate the conduct of the operation, such as proximal and distal anastomotic devices, endoscopic graft harvesting, a move toward arterial grafts. What do you think is the best off-pump coronary operation and why?
Dr Sabik. Let me answer that question in a few parts. I started this study in January of 1997 because that is when we obtained stabilizers and I believe reached a turning point in off-pump revascularization. Our techniques of exposure evolved over the period of the study. The best off-pump operation, I believe, is dependent on the patient. For a young patient, I prefer to use both internal thoracic arteries and use the right internal thoracic artery as a T-graft off of the left internal thoracic artery. This works well in off-pump surgery. The anterior and lateral walls of the left ventricle can be revascularized easily and with the best of conduits. What I use for the right coronary artery depends on the patient’s age and degree of stenosis. If it is a moderate lesion, I would use a saphenous vein graft. In a young patient with a high-grade stenosis, I would use a gastroepiploic or radial artery.
Dr Cohen. Great. Again, I think this is incredibly important data and I really thank you for presenting it to us and also thanks for the opportunity to discuss it.
Dr Sabik. Thank you.
Dr Robert Reichman (Escondido, Calif). Earlier this year 1 of your coauthors, Dr Cosgrove, reported, in a brochure entitled "Surgical Outcomes of the Cleveland Clinic Hospitals," the incidence of off-pump CABG between 2000 and 2002 had decreased by 40%. How do you account for this variation? In other words, a decrease in rate of off-pump coronary artery bypass at the clinic.
Dr Sabik. I think we did the greatest number of off-pump operations in 2001, between 350 and 400 cases, or about 30% of our primary coronary volume. As we have all observed, the number of primary coronary operations continues to decrease at the same time the complexity of primary coronary surgery is increasing. I think last year we did a little less than 300 off-pump operations, and I believe this was due to the combination of those 2 factors.
Dr Eugene Grossi (New York, NY). At the AATS last month we used propensity analysis to look at on- and off-pump patients and we balanced our propensity scores by looking at those factors that contribute to neurologic complications (ie, bad aortas, peripheral vascular disease, etc). In these high-risk patients, we showed advantages to the off-pump technique in terms of neurologic complications and mortality. I've always been intrigued because of the imbalance in the original model between peripheral vascular disease and previous stroke, which you published last year in this Journal. Have you had a chance to reanalyze your data or cull out and identify for us this high-risk patient subset, to determine if those patients will benefit from the OPCAB approach in your experience?
Dr Sabik. We have not done that, Gene. As I said earlier, it is impossible for us to identify a high-risk group because there have been so few events. There were only 3 strokes in the 406 off-pump patients. We need more patients and events to identify which patients benefit most from off-pump revascularization.
Steven R. Gundry (Palm Springs, Calif). I have a comment that confirms your observations. As you know, we reported a 7-year follow-up of actually matched patients from 1989 off-pump and on-pump, and we subsequently did a 10-year follow-up of those same patients. Surprisingly what we found was that, just like you, we did many fewer posterior desending artery and circumflex grafts in those days simply because in those days it was pretty dangerous, but despite that at 10 years the circumflex and the right distribution of the patients who were done off-pump were reintervened at the same rate as those who were done off-pump that had revascularization of that area. That was a striking finding at 10 days, that it really didn't make any difference in those areas, even 10 years later, that we didn't do them. I think you have found the same thing here.
Dr Sabik. And some of that may be due to graft failure. At 10 years you would expect many of the vein grafts to start failing.
Dr Richard Anderson (Seattle, Wash). Just 1 quick question. I would never argue with Dr Blackstone and propensity analysis for case-matching. However, I always get a little bit nervous when in 1 of the primary sets there is a large extraction of patients at the outset and the reasons for that extraction are not transparent, so could you tell us, did you compare the 75 patients that you excluded because they didn't match with the patients that did match? And were there any important differences between those groups?
Dr Sabik. That is an excellent question, Dr Anderson. There are several ways to use propensity scoring. The method we used was a one-to-one match. This technique removed 75 of the off-pump patients from the analysis. Other ways to use propensity scores are to (1) divide the patients into groups as determined by their propensity score, or (2) use the propensity score in a multivariable analysis. Dr Blackstone did the analysis using all 3 methods and essentially came up with the same conclusions. The method of one-to-one matching with propensity scores provided us with excellent matching. The 75 off-pump patients who were excluded from the analyhsis had different preoperative characteristics from the matched patients. They tended to be at extremes of age—very old or very young. They also tended to have either very good renal function or severe renal dysfunction, and they also tended to have less coronary artery disease. We were unable to find similar patients in the on-pump group, and that was due to our selection of these types of patients for off-pump surgery. Mortality was higher in the 75 unmatched off-pump patients. I believe it was 1.5% in the unmatched versus 0.5% in the matched off-pump patients. We believe the higher mortality in the unmatched patients was due to their higher risk characteristics.
|
References |
|---|
|
TopAbstractPatients and methodsResultsDiscussionSummaryReferences |
|---|
This article has been cited by other articles:
|
|
 |
|
  X. Sun, R. M. Lim, P. C Hill, E. Haile, P. J Corso, and J. M Garcia Current Practice and Outcomes of Off-pump Multivessel Coronary Artery Bypass Asian Cardiovasc Thorac Ann, August 1, 2009; 17(4): 362 - 367. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. Sistino Using decision-analysis and meta-analysis to predict coronary artery bypass surgical outcomes - a model for comparing off-pump surgery to miniaturized cardiopulmonary bypass circuits Perfusion, September 1, 2008; 23(5): 255 - 260. [Abstract] [PDF]
|
|
|
|
 |
|
 M. J. Davidson Can the Off-Pump Coronary Artery Bypass Debate Shed Light on Postoperative Right Heart Dysfunction? Circulation, April 29, 2008; 117(17): 2181 - 2183. [Full Text] [PDF]
|
|
|
|
 |
|
 V. Falk and F. W. Mohr Minimally Invasive Myocardial Revascularization Card. Surg. Adult, January 1, 2008; 3(2008): 697 - 710. [Full Text]
|
|
|
|
 |
|
 P. C. Austin Propensity-score matching in the cardiovascular surgery literature from 2004 to 2006: a systematic review and suggestions for improvement. J. Thorac. Cardiovasc. Surg., November 1, 2007; 134(5): 1128 - 1135. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
B. W. Lytle On-Pump and Off-Pump Coronary Bypass Surgery Circulation, September 4, 2007; 116(10): 1108 - 1109. [Full Text] [PDF]
|
|
|
|
|
|
F. D. Rubens and H. Nathan Lessons learned on the path to a healthier brain: dispelling the myths and challenging the hypotheses Perfusion, May 1, 2007; 22(3): 153 - 160. [Abstract] [PDF]
|
|
|
|
 |
|
 T. A. Vassiliades Jr, V. S. Reddy, J. D. Puskas, and R. A. Guyton Long-Term Results of the Endoscopic Atraumatic Coronary Artery Bypass Ann. Thorac. Surg., March 1, 2007; 83(3): 979 - 985. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. Fukui, S. Takanashi, Y. Hosoda, and S. Suehiro Early and Midterm Results of Off-Pump Coronary Artery Bypass Grafting Ann. Thorac. Surg., January 1, 2007; 83(1): 115 - 119. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. Tatoulis, S. Rice, P. Davis, J. C. Goldblatt, and S. Marasco Patterns of postoperative systemic vascular resistance in a randomized trial of conventional on-pump versus off-pump coronary artery bypass graft surgery. Ann. Thorac. Surg., October 1, 2006; 82(4): 1436 - 1444. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 T. Fukui, S. Takanashi, Y. Hosoda, and S. Suehiro In situ bilateral skeletonized internal thoracic arterial grafting for left-side myocardial revascularization using an off-pump technique Interactive CardioVascular and Thoracic Surgery, August 1, 2006; 5(4): 413 - 417. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. Korach, C. T. Hunter, H. L. Lazar, R. J. Shemin, and O. M. Shapira OPCAB for acute LAD dissection due to blunt chest trauma. Ann. Thorac. Surg., July 1, 2006; 82(1): 312 - 314. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 B. C. Reeves, R. Ascione, M. Caputo, and G. D. Angelini Morbidity and mortality following acute conversion from off-pump to on-pump coronary surgery. Eur. J. Cardiothorac. Surg., June 1, 2006; 29(6): 941 - 947. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. Caputo, B. C. Reeves, C. Rajkaruna, H. Awair, and G. D. Angelini Incomplete Revascularization During OPCAB Surgery is Associated With Reduced Mid-Term Event-Free Survival Ann. Thorac. Surg., December 1, 2005; 80(6): 2141 - 2147. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G. J. Murphy, C. A. Rogers, M. Caputo, and G. D. Angelini Acquiring Proficiency in Off-Pump Surgery: Traversing the Learning Curve, Reproducibility, and Quality Control Ann. Thorac. Surg., November 1, 2005; 80(5): 1965 - 1970. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 D. N. Wijeysundera, W. S. Beattie, G. Djaiani, V. Rao, M. A. Borger, K. Karkouti, and R. J. Cusimano Off-Pump Coronary Artery Surgery for Reducing Mortality and Morbidity: Meta-Analysis of Randomized and Observational Studies J. Am. Coll. Cardiol., September 6, 2005; 46(5): 872 - 882. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. M. Calafiore, G. Di Giammarco, G. Teodori, A. L. Iaco, M. Pano, M. Contini, G. Vitolla, and M. Di Mauro Bilateral internal thoracic artery grafting with and without cardiopulmonary bypass: Six-year clinical outcome J. Thorac. Cardiovasc. Surg., August 1, 2005; 130(2): 340 - 345. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
F. W. Sellke, J. M. DiMaio, L. R. Caplan, T. B. Ferguson, T. J. Gardner, L. F. Hiratzka, E. M. Isselbacher, B. W. Lytle, M. J. Mack, J. M. Murkin, et al. Comparing On-Pump and Off-Pump Coronary Artery Bypass Grafting: Numerous Studies but Few Conclusions: A Scientific Statement From the American Heart Association Council on Cardiovascular Surgery and Anesthesia in Collaboration With the Interdisciplinary Working Group on Quality of Care and Outcomes Research Circulation, May 31, 2005; 111(21): 2858 - 2864. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
N. Zimmermann, M. Kurt, A. Wenk, J. Winter, E. Gams, and T. Hohlfeld Is cardiopulmonary bypass a reason for aspirin resistance after coronary artery bypass grafting? Eur. J. Cardiothorac. Surg., April 1, 2005; 27(4): 606 - 610. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. Pepper Controversies in Off-pump Coronary Artery Surgery Clin. Med. Res., February 1, 2005; 3(1): 27 - 33. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 G. J Murphy, R. Ascione, and G. D Angelini Coronary artery bypass grafting on the beating heart: surgical revascularization for the next decade? Eur. Heart J., December 1, 2004; 25(23): 2077 - 2085. [Abstract] [Full Text] [PDF]
|
|
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| 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 |
