Donate Help Contact The AHA Sign In Home
American Heart Association
Circulation
Search: search_blue_button Advanced Search
« Previous Article | Table of Contents | Next Article »
Circulation. 1995;92:734-740

This Article
Right arrow Abstract Freely available
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 Download to citation manager
Right arrow Request Permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Lefkovits, J.
Right arrow Articles by Investigators, f. t. C.-I.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Lefkovits, J.
Right arrow Articles by Investigators, f. t. C.-I.

(Circulation. 1995;92:734-740.)
© 1995 American Heart Association, Inc.

Articles

Predictors and Sequelae of Distal Embolization During Saphenous Vein Graft Intervention From the CAVEAT-II Trial

Jeffrey Lefkovits, MBBS; David R. Holmes, MD; Robert M. Califf, MD; Robert D. Safian, MD; Karen Pieper, MS; Gordon Keeler, MS; Eric J. Topol, MD; for the CAVEAT-II Investigators

From the Department of Cardiology, the Cleveland Clinic Foundation, Cleveland, Ohio (J.L., E.J.T.); the Division of Cardiovascular Diseases, Mayo Clinic, Rochester, Minn (D.R.H.); the Division of Cardiology, Department of Medicine, Duke University Medical Center, Durham, NC (R.M.C., K.P., G.K.); and the Division of Cardiology, William Beaumont Hospital, Royal Oak, Mich (R.D.S.).

Correspondence to Eric J. Topol, MD, Department of Cardiology, One Clinic Center, Cleveland Clinic Foundation, Cleveland, OH 44195.


*    Abstract
up arrowTop
 *Abstract
down arrowIntroduction
 down arrowMethods
down arrowResults
down arrowDiscussion
down arrowReferences
 
Background The purpose of this study was to identify the predictors and sequelae of distal embolization from a multicenter, randomized trial of saphenous vein graft intervention. The CAVEAT-II trial demonstrated that saphenous vein graft directional coronary atherectomy (DCA) was associated with greater angiographic success and less need for repeat intervention compared with percutaneous transluminal coronary angioplasty (PTCA) but at the cost of more acute complications—notably distal embolization.

Methods and Results In CAVEAT-II, 305 patients were randomly assigned to DCA (149 patients) or PTCA (156 patients) for lesions with >60% diameter stenosis in vein grafts >=3 mm in diameter. Distal embolization occurred in 20 patients (13.4%) assigned to DCA and 8 patients (5.1%) assigned to PTCA (P=.011). Independent predictors of distal embolization were use of DCA (71% in distal embolization patients versus 47% in patients without distal embolization, P=.011) and presence of thrombus (39% in distal embolization patients versus 14% in patients without distal embolization, P<.00). In-hospital adverse events were more frequent after distal embolization: 71% versus 20%, odds ratio plus (95% confidence intervals) 9.87 (4.65, 20.94). At 12-month follow-up, adverse event rates were also higher in patients with distal embolization (odds ratio, 3.05 [1.95, 4.76]).

Conclusions In this first prospective multicenter trial of saphenous vein graft intervention, distal embolization was more common after DCA than PTCA and in lesions containing thrombus. It also was associated with worse in-hospital and 12-month outcomes. The risk and sequelae of distal embolization should be considered when choosing a treatment strategy for vein graft disease.


Key Words: embolism • angioplasty


*    Introduction
up arrowTop
 up arrowAbstract
 *Introduction
down arrowMethods
down arrowResults
down arrowDiscussion
down arrowReferences
 
The Coronary Angioplasty Versus Excisional Atherectomy Trial (CAVEAT)-II1 prospectively compared directional coronary atherectomy with percutaneous transluminal coronary angioplasty (PTCA) for discrete saphenous vein graft lesions. The study demonstrated that directional atherectomy resulted in greater initial angiographic improvement, better initial procedural success, and a trend toward a reduction in need for repeat intervention. Yet, as was also demonstrated in the CAVEAT-I trial evaluating the same two interventional modalities in native coronary artery disease,2 directional atherectomy was associated with a higher incidence of acute complications, principally distal embolization and periprocedural myocardial infarction.

Saphenous vein graft atherosclerosis is typically characterized by large friable and ulcerated plaques distributed throughout the length of the graft, with a propensity for thrombus formation. Together, these features make manipulation of the graft, either surgically or by percutaneous techniques, prone to distal embolization.3 4 However, the issue of the true incidence and sequelae of distal embolization is confused by differences in criteria used for its diagnosis.5 6 7 Furthermore, while several investigators have reported their experience with newer technologies including various atherectomy devices6 7 8 9 10 11 12 13 14 15 16 and stents11 17 18 19 20 21 for treatment of vein graft disease, these studies represent nonrandomized, retrospective, and observational series. To date, there are no data on direct, head-to-head comparisons of distal embolization risk for these different modalities, and there is a paucity of information regarding its long-term sequelae.

The aim of this study therefore was to identify from the CAVEAT-II trial the clinical and angiographic factors that were associated with the development of distal embolization and to determine the clinical consequences of this complication.


*    Methods
up arrowTop
 up arrowAbstract
 up arrowIntroduction
 *Methods
down arrowResults
down arrowDiscussion
down arrowReferences
 
Study Design
The CAVEAT-II trial was conducted in 54 centers experienced in percutaneous intervention (52 in North America and 2 in Europe). Patients with a de novo target lesion in a vein graft were eligible for enrollment if they also had symptoms of ischemia or were asymptomatic with a positive functional study. The angiographic criteria included (1) vein graft caliber >=3.0 mm, (2) diameter stenosis >60% by visual assessment, and (3) lesion length <=12 mm. If more than one lesion was present in the target vein graft, all had to be amenable to either technique to conform with single-treatment assignment. After informed consent was obtained, patients were randomized to either conventional balloon angioplasty or directional atherectomy. All patients received aspirin >=160 mg and at least one dose of a calcium channel antagonist before the procedure. Coronary angioplasty or directional atherectomy was performed according to techniques previously described.22 23 Femoral access sheaths were removed 4 to 24 hours after completion of the procedure; ECG were obtained before and within 24 hours of the procedure. Serial creatine kinase levels with myocardial isoenzymes were measured every 8 hours after the procedure for a total of three samples.

Assessment of Distal Embolization
The diagnosis of distal embolization was based on the clinical judgment of the individual investigators performing the procedures. Each of these operators was required to be experienced in interventional cardiology, having performed at least 400 coronary angioplasty procedures with >=85% success rate and more than 50 directional coronary atherectomy procedures with >=80% success in order to participate in the trial. Criteria for diagnosis of distal embolization were provided in the investigators' instruction manual sent to all participating sites. They included angiographic cutoff of a distal branch or vessel at any point during the procedure and/or decreased flow in a distal vessel that was previously patent in the absence of an occlusion at the site of the target lesion. Although all coronary angiograms were also independently assessed by the Cleveland Clinic Foundation angiographic core laboratory, distal embolization was not a prespecified variable and was therefore not systematically looked for. Accordingly, the site-determined definition of distal embolization was used.

Outcomes
For in-hospital outcomes, a composite clinical outcome was used that included death, myocardial infarction, repeat intervention, or emergency coronary artery bypass graft (CABG) surgery. The diagnosis of myocardial infarction was based on the development of new Q waves or creatine kinase myocardial isoenzyme elevation greater than two times the upper limit of normal. Determination of myocardial infarction was performed by an independent adjudication committee blinded to treatment assignment.

The 12-month outcomes were assessed by a composite clinical end point defined as death, myocardial infarction, repeat target vessel intervention, or elective CABG surgery.

Statistical Analysis
Continuous variables are presented as median (25th, 75th percentiles) and categorical variables as frequencies (percentages). A {chi}2 test was used to establish the univariable relation between treatment and distal embolization. Because of the infrequency of distal embolization, a limited number of variables were selected as potentially important descriptors. Logistic regression modeling techniques were used to determine the joint effect of these variables with distal embolization. The importance of each of the final predictor variables is illustrated using the adjusted odds ratios (95% confidence intervals). The coefficients from the final logistic models were used to determine these adjusted odds ratios.

Logistic regression was used to establish the univariable effect of distal embolization on each of the acute outcomes. The interaction of distal embolization with treatment was evaluated for each outcome. Estimates of the 12-month binary outcomes for patients with and without distal embolization were established using Kaplan-Meier survival estimates. The difference in these two rates was tested using a log-rank test. Cox proportional hazard modeling techniques were used to establish the estimates of the distal embolization versus no distal embolization rates for the PTCA and directional atherectomy groups by modeling treatment, distal embolization, and the interaction of the two.


*    Results
up arrowTop
 up arrowAbstract
 up arrowIntroduction
 up arrowMethods
*Results
down arrowDiscussion
down arrowReferences
 
Baseline and Angiographic Characteristics
Three hundred five patients were enrolled into the study; 149 were randomized to directional atherectomy and 156 to PTCA. Distal embolization occurred in 28 patients (9.2%): 20 (13.4%) patients assigned to directional atherectomy and 8 patients (5.1%) in the PTCA group (P=.011). Baseline characteristics of the patients with and without distal embolization were similar between the two groups (Table 1Down). For patients who experienced distal embolization, there were no differences in baseline characteristics between those who underwent directional atherectomy or PTCA. Baseline characteristics were also similar between directional atherectomy and PTCA patients who did not experience distal embolization.


View this table:
[in this window]
[in a new window]
  		Table 1. Baseline Characteristics of Patients With and Without Distal Embolization

The angiographic characteristics of the patients with and without distal embolization are shown in Table 2Down. While median graft age and target lesion location were similar in the two groups, the median vessel diameter was larger in patients with distal embolization (3.7 versus 3.4 mm, P=.04). Higher rates of distal embolization were seen in patients with angiographic thrombus present before treatment (11 [39%] of 28 patients with distal embolization versus 39 [14%] of 277 patients without distal embolization, P=.002). Patients with distal embolization also had more complex lesions, defined as the presence of ulceration or irregular borders (12 patients [43%] with distal embolization versus 74 patients [27%] without distal embolization, P=.081). Treatment crossover from directional atherectomy to PTCA or PTCA to directional atherectomy occurred in 8 patients (29%) with distal embolization and 41 patients (15%) without distal embolization (P=.07).


View this table:
[in this window]
[in a new window]
  		Table 2. Angiographic Characteristics of Patients With and Without Distal Embolization

Predictors of Distal Embolization
Clinical and angiographic variables used to predict distal embolization included treatment assignment, patient age, sex, presence of unstable angina, graft age, vessel size, lesion length, lesion complexity, and lesion thrombus. Multivariable logistic modeling demonstrated that the use of directional atherectomy (odds ratio [OR] plus [95% confidence intervals], 2.87 [1.26, 6.54]) and the presence of thrombus (OR, 3.95 [1.80, 8.66]) were independently associated with distal embolization. The other variables tested were not independently predictive of embolization.

In-Hospital Outcomes
Twenty (71%) of 28 patients with distal embolization had an adverse clinical outcome during their hospital stay compared with 56 (20%) of 277 patients without distal embolization (P<.001) (Table 3Down). The incidences of death and myocardial infarction were higher after distal embolization (2 patients [7%] with distal embolization versus 4 patients [1%] without distal embolization, P=.096, and 19 patients [68%] with distal embolization versus 46 patients [17%] without distal embolization, P<.001, respectively). The need for repeat intervention or emergency CABG was similar in the two groups. For patients with myocardial infarction after distal embolization, 2 of the 5 myocardial infarctions in the PTCA group were Q wave, while 13 of the 14 myocardial infarctions in the directional atherectomy group were non–Q wave. Odds ratios for adverse clinical outcomes after distal embolization are shown in Fig 1Down. Using the composite clinical end point of death, myocardial infarction, repeat intervention, or emergency CABG, distal embolization was associated with an almost 10-fold increase in risk of an adverse acute outcome. The median length of hospitalization was also increased from 2 days to 5 days in patients with distal embolization (P<.001).


View this table:
[in this window]
[in a new window]
  		Table 3. In-Hospital Outcomes



View larger version (12K):
[in this window]
[in a new window]
  		Figure 1. Graph shows odds ratios and 95% confidence intervals for in-hospital outcomes after distal embolization. MI indicates myocardial infarction; CABG, coronary artery bypass surgery; and Composite, composite end point, including death, MI, repeat intervention, or emergency CABG.

12-Month Outcomes
One-year follow-up was obtained in 284 of 305 patients (93%). At 12 months, the death rates and need for repeat intervention or CABG were similar between the two groups. However, distal embolization was associated with a higher 1-year incidence of myocardial infarction (OR, 4.39 [2.61, 7.38]). The odds ratio for an adverse clinical outcome based on the composite end point of death, myocardial infarction, repeat percutaneous intervention, or elective CABG after distal embolization was 3.05 (1.95, 4.76) (Fig 2Down). Fig 3Down shows the Kaplan-Meier plot of freedom from the composite end point.



View larger version (10K):
[in this window]
[in a new window]
  		Figure 2. Graph shows odds ratios and 95% confidence intervals for clinical outcomes at 12 months after distal embolization. See Fig 1Up for abbreviations.



View larger version (13K):
[in this window]
[in a new window]
  		Figure 3. Kaplan-Meier plots for freedom from the composite clinical end point of death, MI, repeat intervention, or CABG for patients (Pts) with and without distal embolization. See Fig 1Up for abbreviations.


*    Discussion
up arrowTop
 up arrowAbstract
 up arrowIntroduction
 up arrowMethods
up arrowResults
*Discussion
down arrowReferences
 
This analysis of the CAVEAT-II trial confirms that intervention in old vein grafts (mean age, 10 years) is associated with an approximate 10% risk of distal embolization. It also demonstrated that there was a greater than twofold increase in distal embolization with directional atherectomy compared with PTCA. Distal embolization was associated with worse acute and 12-month clinical outcomes, with more than two thirds of the patients experiencing an adverse event during their hospital stay. Length of hospitalization was also prolonged by approximately 3 days. At 12 months, only 17% of patients with distal embolization had not experienced an adverse clinical event (death, myocardial infarction, or repeat revascularization) compared with almost 50% of patients without distal embolization. The use of directional atherectomy and the presence of thrombus within the graft were identified as independent predictors of distal embolization risk overall.

The higher rate of distal embolization with directional atherectomy appears to be a principal factor limiting the potential efficacy of this technique for vein graft intervention. The distinct pathological changes within saphenous vein grafts probably account for these higher embolization rates, with plaque distribution tending to be more diffuse and superficial, often very friable, and with an element of overlying thrombus.24 25 26 27 28 29 30 31 The passage of the large, bulky atherectomy device appears to further aggravate this predilection for embolization.

It is noteworthy that while overall myocardial infarction rates after distal embolization were similar in the two groups, two of the five myocardial infarctions after PTCA were Q wave, while 13 of the 14 myocardial infarctions in the directional atherectomy group were non–Q wave. This propensity for significant serum creatine kinase elevations after directional atherectomy was found in the CAVEAT-I trial2 and has subsequently been confirmed in preliminary results from more recent trials of directional atherectomy.32 33 Although some authors have suggested that isolated creatine kinase elevations, especially if less than five times the upper limit of normal, have no long-term sequelae,34 35 36 our data showed a 4.7% in-hospital death rate and 50% incidence of an adverse clinical outcome at 1 year in the 54 patients with non–Q-wave myocardial infarction. Higher non–Q-wave myocardial infarction rates (15.2% directional atherectomy versus 5.5% PTCA) were also found in 199 directional atherectomy patients in the Evaluation of 7E3 for the Prevention of Ischemic Complications (EPIC) trial.37 However, treatment with bolus plus infusion of chimeric 7E3 Fab, a platelet glycoprotein IIb/IIIa receptor antagonist, decreased the non–Q-wave myocardial infarction rate to 4.5% in the directional atherectomy patients. This suggests that the etiology of directional atherectomy–related non–Q-wave myocardial infarction may in fact be platelet-mediated and that potent platelet antagonism can substantially ameliorate the myocardial infarction risk associated with directional atherectomy and saphenous vein graft intervention in general.38

Predictive Factors
Although directional atherectomy was associated with higher acute complication rates in CAVEAT-II overall, there was a trend toward less myocardial infarction and lower CABG surgery rates in those directional atherectomy patients without distal embolization compared with the PTCA group as a whole. This, together with the principal findings of the CAVEAT-II trial, suggests that directional atherectomy may be a useful therapeutic strategy if patients at high risk of distal embolization could be identified and excluded. We demonstrated that the presence of angiographically definable thrombus in the target vessel was strongly associated with distal embolization. The lack of a fibrous cap to vein graft atheromatous plaque, absence of side branches, and relatively low flow velocities have all been put forward as factors contributing to the formation of thrombus within vein grafts.30 Other studies have also found graft age,30 39 40 41 42 indices of plaque burden,5 and diffuseness of disease5 39 to be predictors of distal embolization.

Comparison With Previous Experience
Several other investigators have reported their experience with directional atherectomy in saphenous vein grafts (Table 4Down). In the series by Cowley and colleagues6 of 318 directional atherectomy procedures, the distal embolization rate was 7.2%, while initial success rates and incidence of death and bypass surgery were quite similar to CAVEAT-II. Other reports have found that vein graft atherectomy was associated with a low incidence of major complications (0% to 4%), myocardial infarction and embolization rates similar to PTCA for vein grafts, and inconclusive trends for prediction of significant complications6 10 11 (Table 4Down). However, the data from these earlier series may have been influenced by case-selection bias, and they contrast starkly with the findings from CAVEAT-II, which was the first trial to use a prospective, randomized design to evaluate percutaneous saphenous vein graft intervention. Furthermore, although a number of studies have reported lower incidences of myocardial infarction after directional atherectomy than CAVEAT-II,6 10 11 this may in fact represent underreporting of non–Q-wave myocardial infarction by individual investigating sites. As found in CAVEAT-I, only half of the infarctions detected by the core laboratory were identified by individual sites2 ; this highlights the importance of independent adjudication of key study end points in multicenter trials.


View this table:
[in this window]
[in a new window]
  		Table 4. Published Studies of Saphenous Vein Graft Intervention That Reported Occurrence of Distal Embolization

Alternative Strategies
There is now a mounting experience with alternative percutaneous techniques for vein graft disease (Table 4Up). Stenting of graft lesions not only provides the potential advantages of reliable large lumen attainment, reduction in turbulent flow, and resistance to elastic recoil but also offers a specific mechanism to reduce distal embolization by entrapment of friable atheroma. Leon and colleagues20 reported a 97% procedural success rate for the Palmaz-Schatz stent in saphenous vein graft lesions in a multicenter observational study of 589 patients. The incidence of major complications was 3%, and distal embolization occurred in only 1.5%. Incidences of distal embolization ranging from 0% to 3% have been reported in a number of other series.17 43 44 Despite these encouraging results, vein graft stenting still carries an appreciable risk of stent thrombosis and anticoagulation-related bleeding17 18 19 20 21 as well as the problem of restenosis. Piana and colleagues21 further demonstrated that even with low restenosis rates (17%), the long-term results of stenting old grafts (mean age, 8.7 years) were sobering, with 49% of patients requiring revascularization within 2 years, mainly as a result of progression of disease at other sites.

Transluminal extraction coronary atherectomy (TEC) has been used in stenosed vein grafts,7 12 14 45 46 particularly because of its ability to cut and aspirate clot and atheromatous material, thus theoretically minimizing the risk of distal embolization. However, Safian and colleagues7 found in their series of 146 patients that TEC resulted in frequent acute complications and high restenosis rates. Distal embolization occurred in 11.9%, although the authors point out that one quarter of these were due to air embolism, which may have resulted from improper technique. Hong and colleagues46 found a 12.8% rate of distal embolization in 86 consecutive cases, which was associated with a greater number of major in-hospital complications. The overall application of this technique appears to be limited to selected cases that are still likely to require adjunctive angioplasty.7 46 Laser vein graft angioplasty also has been reported,15 16 47 and although distal embolization rates appear to be lower than for directional atherectomy or TEC (Table 4Up6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 39 42 46 49 50 51 52 53 54 55 ), a recent report on the acute complications associated with excimer laser angioplasty found a sixfold increase in distal embolization during vein graft laser angioplasty and recommended a cautious approach, particularly with friable lesions.48

Limitations
This study has a number of limitations that should be kept in mind. The definition of distal embolization used in this study included patients with reduced distal flow in the graft after the procedure. This is a relatively nonspecific marker and could have led to the inclusion of cases that could have otherwise been labeled "no reflow" or classified as microvascular spasm. However, while the pathogenesis of these events remains uncertain, they may have been due to distal microembolization. Furthermore, investigators have used varying definitions of distal embolization,5 6 7 leaving the issue of the most appropriate definition confusing and uncertain. The choice of angiographic cutoff of a distal vessel or reduced flow in an otherwise patent graft in this study is representative of other investigators' definitions and can be justified on pathological grounds.

Second, the inclusion criteria for this study stipulated that lesions were to be discrete and in vein grafts not diffusely diseased. Despite this, the average age of the grafts was 9.6 years for directional atherectomy patients and 9.9 years in the PTCA group. Thus, this study may in fact represent a distinct population of grafts that are old but not diffusely diseased, making extrapolation of its results to younger grafts or those with diffuse disease uncertain.

While the diagnosis of myocardial infarction was performed by an independent adjudication committee blinded to treatment assignment, the occurrence of distal embolization was determined by the individual site investigators, introducing a potential source of bias. Although all coronary angiograms in CAVEAT-II were reviewed by a core angiographic laboratory, distal embolization was not one of the prespecified angiographic variables and was therefore not systematically looked for. It was also considered that individual sites were in a better position to identify more subtle instances of distal embolization such as transient distal vessel cutoff or reduced flow that coincided with device manipulation within the graft, which may have otherwise gone undetected by the core angiographic laboratory.

Conclusions
With increasing numbers of CABG operations being performed, the need for effective treatment for vein graft disease will continue to expand. Reoperation is technically difficult and associated with increased morbidity and mortality. Yet old vein grafts are especially challenging for conventional balloon angioplasty, being limited by high restenosis and reocclusion rates. The overall results of the CAVEAT-II trial demonstrated that directional atherectomy has a modest advantage over PTCA. However, this was at the price of increased acute complications—notably distal embolization, which in turn was associated with worse in-hospital outcomes, prolonged hospital stays, and more clinical ischemic events in the ensuing 12 months. Although identification of factors predictive of distal embolization such as the presence of thrombus may help exclude patients at high risk, future improvements such as ultrasound-guided directional atherectomy, coated stents, and potent adjunctive antithrombotic and antiplatelet therapy may offer further refinements to percutaneous interventional techniques. While approaches may differ, the search for the optimal therapy continues, as effective treatment of vein graft atherosclerosis is and will continue to be a paramount challenge for cardiovascular medicine.


*    Acknowledgments
 
The authors wish to thank Nicole Gershov for her helpful comments and expert assistance with the preparation of the manuscript.


*    Footnotes
 
1 A list of CAVEAT-II participating investigators and centers is published in Circulation (1995;91:1966-1974). Back

Received December 19, 1994; revision received February 19, 1995; accepted February 28, 1995.


*    References
up arrowTop
 up arrowAbstract
 up arrowIntroduction
 up arrowMethods
up arrowResults
up arrowDiscussion
*References
 

  1. Holmes DR Jr, Topol EJ, Califf RM, Berdan LG, Leya F, Berger PB, Whitlow PL, Safian RD, Adelman AG, Kellett MA, Talley JD, Shani J, Gottlieb RS, Pinkerton CA, Lee KL, Keeler GP, Ellis SG, for the CAVEAT-II Investigators. A multicenter randomized trial of coronary angioplasty versus directional atherectomy for patients with saphenous vein bypass graft lesions. Circulation. 1995;91:1966-1974. [Abstract/Free Full Text]
  2. Topol EJ, Leya F, Pinkerton CA, Whitlow PL, Hofling B, Simonton CA, Masden RR, Serruys PW, Leon MB, Williams DO, King SB, Mark DB, Isner JM, Holmes DR Jr, Ellis SG, Lee KL, Keeler GP, Berdan LG, Hinohara T, Califf RM. A comparison of directional atherectomy with coronary angioplasty in patients with coronary artery disease. N Engl J Med. 1993;329:221-227. [Abstract/Free Full Text]
  3. Douglas JS. Percutaneous intervention in patients with prior coronary bypass surgery. In: Topol EJ, ed. Textbook of Interventional Cardiology. Philadelphia, Pa: WB Saunders; 1994:339-354.
  4. Keon WJ, Heggtveit HA, Leduc J. Perioperative myocardial infarction caused by atheroembolism. J Thorac Cardiovasc Surg. 1982;84:849-855. [Abstract]
  5. Liu MW, Douglas JS, Lembo NJ, King SB. Angiographic predictors of a rise in serum creatine kinase (distal embolization) after balloon angioplasty of saphenous vein coronary artery bypass grafts. Am J Cardiol. 1993;72:514-517. [Medline] [Order article via Infotrieve]
  6. Cowley MJ, Whitlow PL, Baim DS, Hinohara T, Hall K, Simpson JB. Directional coronary atherectomy of saphenous vein graft narrowings: investigational experience. Am J Cardiol. 1993;72:30E-34E. [Medline] [Order article via Infotrieve]
  7. Safian RD, Grines CL, May MA, Lichtenberg A, Juran N, Schreiber TL, Pavlides G, Meany TB, Savas V, O'Neill WW. Clinical and angiographic results of transluminal extraction coronary atherectomy in saphenous vein bypass grafts. Circulation. 1994;89:302-312. [Abstract/Free Full Text]
  8. Kaufmann UP, Garratt KN, Vlietstra RE, Holmes DR Jr. Transluminal atherectomy of saphenous vein aortocoronary bypass grafts. Am J Cardiol. 1990;65:1430-1433. [Medline] [Order article via Infotrieve]
  9. Selmon MR, Hinohara T, Robertson GC, Rowe MH, Vetter JW, Bartzokis TC, Braden LJ, Simpson JB. Directional coronary atherectomy for saphenous vein graft stenoses. J Am Coll Cardiol. 1991;17(suppl A):23A. Abstract.
  10. Garratt KN, Holmes DR Jr, Bell MR, Berger PB, Kaufmann UP, Bresnahan JF, Vlietstra RE. Results of directional atherectomy of primary atheromatous and restenosis lesions in coronary arteries and saphenous vein grafts. Am J Cardiol. 1992;70:449-454. [Medline] [Order article via Infotrieve]
  11. Pomerantz RM, Kuntz RE, Carrozza JP, Fishman RF, Mansour M, Schnitt SJ, Safian RD, Baim DS. Acute and long-term outcome of narrowed saphenous venous grafts treated by endoluminal stenting and directional atherectomy. Am J Cardiol. 1992;70:161-167. [Medline] [Order article via Infotrieve]
  12. Meany T, Kramer B, Knopf W, Pichard A, Sketch M Jr, Juran N, Stack R, O'Neill WW. Multicenter experience of atherectomy of saphenous vein grafts: immediate results and follow-up. J Am Coll Cardiol. 1992;19(suppl A):262A. Abstract.
  13. Popma JJ, Leon MB, Mintz GS, Kent KM, Satler LF, Garrand TJ, Pichard AD. Results of coronary angioplasty using the transluminal extraction catheter. Am J Cardiol. 1992;70:1526-1532. [Medline] [Order article via Infotrieve]
  14. Twidale N, Barth CW, Kipperman RM, Bowles MH, Galichia JP. Acute results and long-term outcome of transluminal extraction catheter atherectomy for saphenous vein graft stenoses. Cathet Cardiovasc Diagn. 1994;31:187-191. [Medline] [Order article via Infotrieve]
  15. Linnemeier TJ, Rothbaum DA, Cumberland DC, Landin RJ, Hodes ZI, Ball MW. Percutaneous laser-assisted thermal coronary angioplasty in native coronary arteries and saphenous vein grafts: initial results and angiographic follow-up. J Invasive Cardiol. 1990;2:133-138. [Medline] [Order article via Infotrieve]
  16. Untereker WJ, Litvack F, Margolis JR, Roubin GS, Hartzler GO, White RH, Bresnahan JF, Rothbaum DA, Hart EK, Ogilby JD, and ELCA Investigators. Excimer laser angioplasty of saphenous vein grafts. Circulation. 1991;84(suppl II):II-249. Abstract.
  17. de Scheerder IK, Strauss BH, de Feyter PJ, Beatt KJ, Baur LHB, Wijns W, Heyndrix GR, Suryapranata H, van den Brand M, Buis B, Serruys PW. Stenting of venous bypass grafts: a new treatment modality for patients who are poor candidates for reintervention. Am Heart J. 1992;123:1046-1054. [Medline] [Order article via Infotrieve]
  18. Bilodeau L, Iyer S, Cannon AD, Agrawal SK, Hearn JA, Dean LS, Baxley WA, Macander PJ, Breland J, Roubin GS. Flexible coil stent (Cook Inc) in saphenous vein grafts: clinical and angiographic follow-up. J Am Coll Cardiol. 1992;19:264A. Abstract.
  19. Strumpf RK, Mehta SS, Ponder R, Heuser RR. Palmaz-Schatz stent implantation in stenosed saphenous vein grafts: clinical and angiographic follow-up. Am Heart J. 1992;123:1329-1336. [Medline] [Order article via Infotrieve]
  20. Leon MB, Wong SC, Pichard AD. Balloon-expandable stent implantation in saphenous vein grafts. In: Hermann HC, Hirshfeld JW, eds. Clinical Use of the Palmaz-Schatz Intracoronary Stent. Mt Kisco, NY: Futura; 1993:111-121.
  21. Piana RN, Moscucci M, Cohen DJ, Kugelmass AD, Senerchia C, Kuntz RE, Baim DS, Carrozza JP. Palmaz-Schatz stenting for treatment of focal vein graft stenosis: immediate results and long-term outcome. J Am Coll Cardiol. 1994;23:1296-1304. [Abstract]
  22. Ellis SG. Elective coronary angioplasty: technique and complications. In: Topol EJ, ed. Textbook of Interventional Cardiology. Philadelphia, Pa: WB Saunders; 1993:186-207.
  23. Safian RD, Gelbfish JS, Erny RE, Schnitt SJ, Schmidt DA, Baim DS. Coronary atherectomy: clinical, angiographic, and histological findings and observations regarding potential mechanisms. Circulation. 1990;82:69-79. [Abstract/Free Full Text]
  24. Bourassa MG, Campeau L, Lesperance J. Changes in grafts and coronary arteries after coronary bypass surgery. Cardiovasc Clin. 1991;21:83-100. [Medline] [Order article via Infotrieve]
  25. Solymoss BC, Leung TK, Pelletier LC, Campeau LC. Pathologic changes in coronary artery saphenous vein grafts and related etiologic factors. Cardiovasc Clin. 1991;21:45-65. [Medline] [Order article via Infotrieve]
  26. Neitzel GF, Barborink JJ, Pintar K, Qureshi I. Atherosclerosis in aortocoronary bypass grafts: morphologic study and risk factor analysis 6 to 12 years after surgery. Atherosclerosis. 1986;6:594-600.
  27. Lie JT, Lawrie GM, Morris GC. Aortocoronary bypass graft atherosclerosis: anatomic study of 99 vein grafts from normal and hyperlipoproteinemic patients up to 75 months post-operatively. Am J Cardiol. 1977;40:906-914. [Medline] [Order article via Infotrieve]
  28. Smith SH, Gerr JC. Morphology of saphenous vein coronary artery bypass grafts. Arch Pathol Lab Med. 1983;107:13-18. [Medline] [Order article via Infotrieve]
  29. Kalan JM, Roberts WC. Morphologic findings in saphenous veins used as coronary arterial bypass conduits for longer than one year: necropsy analysis of 53 patients, 123 saphenous veins and 1865 five millimeter segments of vein. Am Heart J. 1990;119:1164-1184. [Medline] [Order article via Infotrieve]
  30. de Feyter PJ, van Suylen RJ, de Jaegere PPT, Topol EJ, Serruys PW. Balloon angioplasty for the treatment of lesions in saphenous vein bypass grafts. J Am Coll Cardiol. 1993;21:1539-1549. [Abstract]
  31. Garratt KN, Edwards WD, Kaufmann UP, Vlietstra RE, Holmes DR Jr. Differential histopathology of primary atherosclerotic and restenotic lesions in coronary arteries and saphenous vein bypass grafts: analysis of tissue obtained from 73 patients by directional atherectomy. J Am Coll Cardiol. 1991;17:442-448. [Abstract]
  32. Baim DS, Kuntz RE, Popma JJ, Leon MB, Ho KKL, for BOAT Investigators. Results of directional atherectomy in the `pilot' phase of BOAT. Circulation. 1994;90(suppl I):I-214. Abstract.
  33. Leon MB, Popma JJ, Kuntz RE, Mintz GS, Kent KM, Bersin RM, Simonton C, Hinohara T, Baim DS, for Optimal Atherectomy Restenosis (OARS) Investigators. Acute angiographic and ultrasound results of directional atherectomy in OARS. Circulation. 1994;90(suppl I):I-213. Abstract.
  34. Oh JK, Shub C, Ilstrup DM, Reeder GS. Creatine kinase release after successful percutaneous transluminal coronary angioplasty. Am Heart J. 1985;109:1225-1231. [Medline] [Order article via Infotrieve]
  35. Klein LW, Kramer BL, Howard E, Lesch M. Incidence and clinical significance of transient creatine kinase elevations and the diagnosis of non-Q wave myocardial infarction associated with coronary angioplasty. J Am Coll Cardiol. 1991;17:621-626. [Abstract]
  36. Kugelmass AD, Cohen DJ, Moscucci M, Piana RN, Senerchia C, Kuntz RE, Baim DS. Elevation of the creatine kinase myocardial isoform following otherwise successful directional coronary atherectomy and stenting. Am J Cardiol. 1994;74:748-754. [Medline] [Order article via Infotrieve]
  37. EPIC Investigators. Use of a monoclonal antibody directed against the platelet glycoprotein IIb/IIIa receptor in high-risk coronary angioplasty. N Engl J Med. 1994;330:956-961. [Abstract/Free Full Text]
  38. Lefkovits J, Anderson K, Weisman H, Topol EJ, for EPIC Investigators. Increased risk of non-Q MI following DCA: evidence for a platelet dependent mechanism from the EPIC trial. Circulation. 1994;90(suppl I):I-214. Abstract.
  39. Cote G, Myler RK, Stertzer SH, Clark DA, Fishman-Rosen J, Murphy M, Shaw RE. Percutaneous transluminal angioplasty of stenotic coronary artery bypass grafts: 5 years' experience. J Am Coll Cardiol. 1987;9:8-17. [Abstract]
  40. Dorros G, Lewin RF, Mathiak LM. Coronary angioplasty in patients with prior coronary artery bypass surgery: all prior coronary artery bypass surgery patients and patients more than 5 years after coronary bypass surgery. Cardiol Clin. 1989;7:791-803. [Medline] [Order article via Infotrieve]
  41. Ernst SM, van der Feltz TA, Ascoop CA, Bal ET, Vermeulen FE, Knaepen PJ, van Bogerijen L, van den Berg EJ, Plokker HW. Percutaneous transluminal coronary angioplasty in patients with prior coronary artery bypass grafting. J Thorac Cardiovasc Surg. 1987;93:268-275. [Abstract]
  42. Platko WP, Hollman J, Whitlow PL, Franco I. Percutaneous transluminal coronary angioplasty of saphenous vein graft stenosis: long-term follow-up. J Am Coll Cardiol. 1989;14:1645-1650. [Abstract]
  43. White CJ, Ramee SR, Collins TJ, Escobar A, Jain SP. Placement of `biliary' stents in saphenous vein coronary bypass grafts. Cathet Cardiovasc Diagn. 1993;30:91-95. [Medline] [Order article via Infotrieve]
  44. Urban P, Sigwart U, Golf S, Kaufmann U, Sadeghi H, Kappenberger L. Intravascular stenting for stenosis of aortocoronary venous bypass grafts. J Am Coll Cardiol. 1989;13:1085-1091. [Abstract]
  45. Popma JJ, Mintz GS, Satler LF, Pichard AD, Kent KM, Chuang YC, Matar F, Bucher TA, Merritt AJ, Leon MB. Clinical and angiographic outcome after directional coronary atherectomy. Am J Cardiol. 1993;72:55E-64E. [Medline] [Order article via Infotrieve]
  46. Hong MK, Popma JJ, Pichard AD, Kent KM, Satler LF, Chuang YC, Mintz GS, Keller MB, Leon MB. Clinical significance of distal embolization after transluminal extraction atherectomy in diffusely diseased saphenous vein grafts. Am Heart J. 1994;127:1496-1503. [Medline] [Order article via Infotrieve]
  47. Litvack F, Grundfest WS, Goldenberg T, Laudenslager J, Forrester JS. Percutaneous excimer laser angioplasty of aortocoronary saphenous vein grafts. J Am Coll Cardiol. 1989;14:803-808. [Abstract]
  48. Baumbach A, Bittl JA, Fleck E, Geschwind HJ, Sanborn TA, Tcheng JE, Karsch KR, Coinvestigators of the US and European Percutaneous Excimer Laser Coronary Angioplasty (PELCA) Registries. Acute complications of excimer laser coronary angioplasty: a detailed analysis of multicenter results. J Am Coll Cardiol. 1994;23:1305-1313. [Abstract]
  49. Douglas JS, Gruentzig AR, King SB, Hollman J, Ischinger T, Meier B, Craver JM, Jones EL, Waller JL, Bone DK, Guyton R. Percutaneous transluminal coronary angioplasty in patients with prior coronary bypass surgery. J Am Coll Cardiol. 1983;2:745-754. [Abstract]
  50. El Gamal M, Bonnier H, Michels R, Heijman J, Stassen E. Percutaneous transluminal angioplasty of stenosed aortocoronary bypass grafts. Br Heart J. 1984;52:617-620. [Abstract/Free Full Text]
  51. Block PC, Cowley MJ, Kaltenbach M, Kent KM, Simpson J. Percutaneous angioplasty of stenoses of bypass grafts or of bypass graft anastamotic sites. Am J Cardiol. 1984;53:666-668. [Medline] [Order article via Infotrieve]
  52. Corbelli J, Franco I, Hollman J, Simpfendorfer C, Galan K. Percutaneous transluminal coronary angioplasty after previous coronary artery bypass surgery. Am J Cardiol. 1985;56:398-403. [Medline] [Order article via Infotrieve]
  53. Dorros G, Lewin RF, Mathiak LM, Johnson WD, Brenowitz J, Schmahl T, Tector A. Percutaneous transluminal coronary angioplasty in patients with two or more previous coronary artery bypass grafting operations. Am J Cardiol. 1988;61:1243-1247. [Medline] [Order article via Infotrieve]
  54. Reed DC, Beller GA, Nygaard TW, Tedesco C, Watson DD, Burwell LR. The clinical efficacy and scintigraphic evaluation of post-coronary bypass patients undergoing percutaneous transluminal coronary angioplasty for recurrent angina pectoris. Am Heart J. 1989;117:60-70. [Medline] [Order article via Infotrieve]
  55. Reeves F, Bonan R, Cote H, Crepeau J, deGuise P, Gosselin G, Campeau L, Lesperance J. Long-term angiographic follow-up after angioplasty of venous coronary bypass grafts. Am Heart J. 1991;122:620-627.[Medline] [Order article via Infotrieve]



This article has been cited by other articles:


Home page
 CirculationHome page
A. Coolong, D. S. Baim, R. E. Kuntz, A. J. O'Malley, S. Marulkar, D. E. Cutlip, J. J. Popma, and L. Mauri
Saphenous Vein Graft Stenting and Major Adverse Cardiac Events: A Predictive Model Derived From a Pooled Analysis of 3958 Patients
Circulation, February 12, 2008; 117(6): 790 - 797.
[Abstract] [Full Text] [PDF]

Home page
 JAMAHome page
PREVENT IV Investigators
Efficacy and Safety of Edifoligide, an E2F Transcription Factor Decoy, for Prevention of Vein Graft Failure Following Coronary Artery Bypass Graft Surgery: PREVENT IV: A Randomized Controlled Trial
JAMA, November 16, 2005; 294(19): 2446 - 2454.
[Abstract] [Full Text] [PDF]

Home page
 HeartHome page
G Sangiorgi and A Colombo
Embolic protection devices
Heart, September 1, 2003; 89(9): 990 - 992.
[Full Text] [PDF]

Home page
 CirculationHome page
U. Limbruno, A. Micheli, M. De Carlo, G. Amoroso, R. Rossini, C. Palagi, V. Di Bello, A. S. Petronio, G. Fontanini, and M. Mariani
Mechanical Prevention of Distal Embolization During Primary Angioplasty: Safety, Feasibility, and Impact on Myocardial Reperfusion
Circulation, July 15, 2003; 108(2): 171 - 176.
[Abstract] [Full Text] [PDF]

Home page
 CirculationHome page
G. Stankovic, A. Colombo, P. Presbitero, F. van den Branden, L. Inglese, C. Cernigliaro, L. Niccoli, A. L. Bartorelli, P. Rubartelli, N. Reifart, et al.
Randomized Evaluation of Polytetrafluoroethylene-Covered Stent in Saphenous Vein Grafts: The Randomized Evaluation of polytetrafluoroethylene COVERed stent in Saphenous vein grafts (RECOVERS) Trial
Circulation, July 8, 2003; 108(1): 37 - 42.
[Abstract] [Full Text] [PDF]

Home page
 CirculationHome page
M. Singh, U. Rosenschein, K. K.L. Ho, P. B. Berger, R. Kuntz, and D. R. Holmes, Jr
Treatment of Saphenous Vein Bypass Grafts With Ultrasound Thrombolysis: A Randomized Study (ATLAS)
Circulation, May 13, 2003; 107(18): 2331 - 2336.
[Abstract] [Full Text] [PDF]

Home page
 J Am Coll CardiolHome page
G. W. Stone, C. Rogers, S. Ramee, C. White, R. E. Kuntz, J. J. Popma, J. George, S. Almany, and S. Bailey
Distal filter protection during saphenous vein graft stenting: Technical and clinical correlates of efficacy
J. Am. Coll. Cardiol., November 20, 2002; 40(10): 1882 - 1888.
[Abstract] [Full Text] [PDF]

Home page
 CirculationHome page
E. Grube, U. Gerckens, A. C. Yeung, S. Rowold, N. Kirchhof, J. Sedgewick, J. S. Yadav, and S. Stertzer
Prevention of Distal Embolization During Coronary Angioplasty in Saphenous Vein Grafts and Native Vessels Using Porous Filter Protection
Circulation, November 13, 2001; 104(20): 2436 - 2441.
[Abstract] [Full Text] [PDF]

Home page
 CirculationHome page
S. Baldus, R. Koster, M. Elsner, D. H. Walter, R. Arnold, W. Auch-Schwelk, J. Berger, M. Rau, T. Meinertz, A. M. Zeiher, et al.
Treatment of Aortocoronary Vein Graft Lesions With Membrane-Covered Stents : A Multicenter Surveillance Trial
Circulation, October 24, 2000; 102(17): 2024 - 2027.
[Abstract] [Full Text] [PDF]

Home page
 J Am Coll CardiolHome page
R. Choussat, A. J. R. Black, I. Bossi, T. Joseph, J. Fajadet, and J. Marco
Long-term clinical outcome after endoluminal reconstruction of diffusely degenerated saphenous vein grafts with less-shortening wallstents
J. Am. Coll. Cardiol., August 1, 2000; 36(2): 387 - 394.
[Abstract] [Full Text] [PDF]

Home page
 J Am Coll CardiolHome page
K. A. Eagle, R. A. Guyton, R. Davidoff, G. A. Ewy, J. Fonger, T. J. Gardner, J. P. Gott, H. C. Herrmann, R. A. Marlow, W. C. Nugent, et al.
ACC/AHA guidelines for coronary artery bypass graft surgery: A report of the American College of Cardiology/ American Heart Association task force on Practice Guidelines (Committee to revise the 1991 Guidelines for Coronary Artery Bypass Graft Surgery)
J. Am. Coll. Cardiol., October 1, 1999; 34(4): 1262 - 1347.
[Full Text] [PDF]

Home page
 J Am Coll CardiolHome page
P. J. Scanlon, D. P. Faxon, A.-M. Audet, B. Carabello, G. J. Dehmer, K. A. Eagle, R. D. Legako, D. F. Leon, J. A. Murray, S. E. Nissen, et al.
ACC/AHA guidelines for coronary angiography: A report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Committee on Coronary Angiography) developed in collaboration with the Society for Cardiac Angiography and Interventions
J. Am. Coll. Cardiol., May 1, 1999; 33(6): 1756 - 1824.
[Full Text] [PDF]

Home page
 CirculationHome page
D. R. Holmes Jr and P. B. Berger
Percutaneous Revascularization of Occluded Vein Grafts : Is It Still a Temptation to Be Resisted?
Circulation, January 12, 1999; 99(1): 8 - 11.
[Full Text] [PDF]

Home page
 CirculationHome page
U. Rosenschein, G. Gaul, R. Erbel, F. Amann, D. Velasguez, H. Stoerger, R. Simon, G. Gomez, J. Troster, A. Bartorelli, et al.
Percutaneous Transluminal Therapy of Occluded Saphenous Vein Grafts : Can the Challenge Be Met With Ultrasound Thrombolysis?
Circulation, January 12, 1999; 99(1): 26 - 29.
[Abstract] [Full Text] [PDF]

Home page
 CirculationHome page
J. G. Motwani and E. J. Topol
Aortocoronary Saphenous Vein Graft Disease : Pathogenesis, Predisposition, and Prevention
Circulation, March 10, 1998; 97(9): 916 - 931.
[Abstract] [Full Text] [PDF]

Home page
 NEJMHome page
M. P. Savage, J. S. Douglas, D. L. Fischman, C. J. Pepine, S. B. King, J. A. Werner, S. R. Bailey, P. A. Overlie, S. H. Fenton, J. A. Brinker, et al.
Stent Placement Compared with Balloon Angioplasty for Obstructed Coronary Bypass Grafts
N. Engl. J. Med., September 11, 1997; 337(11): 740 - 747.
[Abstract] [Full Text] [PDF]

Home page
 JAMAHome page
PREVENT IV Investigators
Efficacy and Safety of Edifoligide, an E2F Transcription Factor Decoy, for Prevention of Vein Graft Failure Following Coronary Artery Bypass Graft Surgery: PREVENT IV: A Randomized Controlled Trial
JAMA, November 16, 2005; 294(19): 2446 - 2454.
[Abstract] [Full Text