Acute and long-term outcome of narrowed saphenous venous grafts treated by endoluminal stenting and directional atherectomy

Impact of internal mammary artery conduit on long-term outcomes after percutaneous intervention of saphenous vein graft

BACKGROUND

The influence of an internal mammary artery (IMA) graft on long-term outcomes after percutaneous saphenous vein graft (SVG) intervention is currently unknown.

METHODS AND RESULTS

To examine the impact of IMA on outcomes in patients undergoing SVG interventions, we analyzed 2119 patients from the Duke Cardiovascular Disease Database (1986-2003) with prior coronary artery bypass surgery undergoing cardiac catheterization who had at least 1 SVG graft. Patients were categorized into 4 groups: group I, SVG intervention and patent IMA; group II, no SVG intervention and patent IMA; group III, SVG intervention without patent IMA; and group IV, no SVG intervention without patent IMA. At a median follow-up of 4.8 years (interquartile range, 2.1 to 8.8 years), adjusted survival rates in groups I, II, III, and IV were 72.8%, 72.3%, 64.5%, and 58.9%, respectively. Multivariate Cox proportional hazards modeling showed similar survival for groups I and II (P=0.63) and for groups III and IV (P=0.33). The presence of IMA graft was related to lower long-term mortality (adjusted hazard ratio [HR], 0.69; 95% CI, 0.58 to 0.82), whereas SVG intervention was not associated with long-term mortality (adjusted HR, 0.94; 95% CI, 0.81 to 1.10). In contrast, the adjusted event-free rates for nonfatal myocardial infarction were lower in the SVG intervention groups (groups I and III) than in the non-SVG intervention groups (groups II and IV) (HR for SVG intervention versus no SVG intervention, 3.19; 95% CI, 2.18 to 4.66), with the presence of patent IMA conferring no significant benefit on this outcome (HR, 1.37; 95% CI, 0.91 to 2.08).

CONCLUSIONS

In patients undergoing SVG interventions, survival, but not nonfatal myocardial infarction, is favorably influenced by the presence of patent IMA. In contrast, SVG intervention had no measurable survival benefit but was associated with an increased risk of nonfatal myocardial infarction.

Assessing a strategy of initial stand-alone extractional atherectomy followed by staged stent placement in degenerated saphenous vein graft lesions

To assess whether a staged strategy (initial stand alone transluminal extraction atherectomy and coumadin therapy followed by stenting six weeks later) could reduce ischemic complications in degenerated saphenous vein graft (SVG) interventions, we studied 72 patients undergoing percutaneous interventions of degenerated SVG. Patients were divided into two groups; 28 were treated with a staged strategy (group I) and 44 with similar lesion characteristics were treated with a definitive initial procedure with transluminal extraction atherectomy +/- adjunctive balloon angioplasty and stenting (group II). Procedural success, major in-hospital complications (death, Q-wave myocardial infarction, and emergent coronary bypass surgery), and incidence of distal embolization were compared between the 2 groups. Procedural success was lower (92% vs 100%, p = 0.14) and major in-hospital complications were higher (0% vs 11%, p = 0.14) in group II. Distal embolization occurred in 11% of the patients in group I compared with 23% of the patients in group II (p = 0.19). At 6 week follow-up (group I), 9 patients (33%) had negative symptoms, 11 (41%) underwent stent implantation, 3 (11%) did not require any further therapy (without significant stenosis), and 4 (14%) had total occlusions. We therefore conclude that this staged strategy in degenerated SVG appears to reduce distal embolization but most importantly avoids major in-hospital complications, including any deaths either at the time of initial procedure or during the 6-week follow-up period.

Influence of diabetes mellitus on early and late clinical outcomes in saphenous vein graft stenting

OBJECTIVES

The purpose of this study was to compare early and late clinical outcomes in diabetic and nondiabetic patients after stent implantation in saphenous vein grafts (SVG).

BACKGROUND

Patients with diabetes mellitus have less favorable acute and long-term outcomes after stent implantation in native coronary arteries. The impact of diabetes on SVG stenting, however, is not known.

METHODS

We studied 908 consecutive patients (1,366 SVG lesions) treated with Palmaz-Schatz stents. In-hospital and late clinical outcomes (death, Q-wave myocardial infarction and repeat revascularization rates at one year) were compared between diabetic (n = 290) and nondiabetic (n = 618) patients.

RESULTS

In-hospital mortality was significantly higher in diabetic as compared with nondiabetic patients (2.2% vs. 0.3%, p = 0.003). At one-year follow-up, target lesion revascularization (TLR) was 16.6% in diabetic and 12.3% in nondiabetic patients (p = 0.03). Overall cardiac event-free survival (freedom from death, Q-wave myocardial infarction and any coronary revascularization procedure) at one year was significantly lower in the diabetic (68%) compared with the nondiabetic patients (79%, p = 0.0003). By Cox regression analysis, diabetes mellitus was an independent predictor of both TLR (relative risk: 1.23; confidence interval: 0.96 to 1.58; p = 0.004) and late cardiac events (relative risk: 1.40; confidence interval: 1.05 to 1.86; p = 0.02).

CONCLUSIONS

Patients with diabetes undergoing stent implantation in SVG have: 1) higher in-hospital and late mortality, 2) higher one-year TLR rates, and 3) significantly lower one-year cardiac event-free survival. Thus, diabetic patients have less favorable acute and late clinical outcomes after stent implantation in SVG lesions.

Long-term clinical outcome after endoluminal reconstruction of diffusely degenerated saphenous vein grafts with less-shortening wallstents

OBJECTIVES

This study was designed to evaluate the immediate and long-term clinical results of patients undergoing endoluminal reconstruction in diffusely degenerated saphenous vein grafts (SVGs) with elective implantation of one or more less-shortening Wallstents.

BACKGROUND

The optimal treatment strategy for patients with diffusely degenerated SVGs is controversial. Endoluminal reconstruction by stent implantation is one proposed strategy; however, there are few data regarding long-term clinical outcome.

METHODS

Between May 1995 and September 1998, 6,534 consecutive patients underwent angioplasty in our institution, including 440 who were treated for SVG lesions. Of these, 126 (115 men, 11 women, median age 69.5 years, range: 33-86 years) with old SVGs (mean age: 13+/-5 years) diffusely degenerated stenosed or occluded (mean lesion length: 27+/-12 mm) were treated electively with implantation of one or multiple (total 197) less-shortening Wallstents.

RESULTS

Before discharge, 13 patients (10.3%) sustained at least one major cardiovascular event, including 4 deaths (3.2%), 11 myocardial infarctions (MI) (8.7%), and 3 repeat revascularizations (target vessel = 1, nontarget vessel = 2, 2.4%). Surviving patients were followed for 22+/-11 months: 13 patients (11.1%) died, 11 (9.4%) sustained an MI, 37 underwent angioplasty (31.6%), and 4 (3.4%) underwent bypass surgery. The estimated three-year event-free survival rates (freedom from death, and freedom from death/MI/target vessel revascularization) were (mean +/- SE) 81.1+/-7.8% and 43.2+/-18.5%, respectively.

CONCLUSIONS

The long-term clinical outcome of patients undergoing endoluminal reconstruction in diffusely degenerated SVG is relatively poor, mainly because of a high incidence of death or MI and the frequent need for repeat angioplasty. It is unlikely that percutaneous intervention alone will provide a satisfactory or definitive solution for these patients.

Retrieval and analysis of particulate debris after saphenous vein graft intervention

OBJECTIVES

This study was designed to evaluate the composition and quantity of particulate debris resulting from vein graft intervention.

BACKGROUND

Distal embolization and "no reflow" are frequent and important complications resulting from angioplasty of diseased saphenous vein grafts. Little is known about the composition and quantity of embolic particulate debris associated with vein graft intervention, and no intervention has been shown to protect against its clinical consequences.

METHODS

A catheter system, designed to contain, retrieve and protect against distal embolization of this material, was evaluated during 27 percutaneous interventional saphenous vein graft procedures. Clinical, angiographic and pathologic analyses were performed.

RESULTS

The duration of distal graft occlusion required to allow intervention and subsequent debris removal was 150 +/- 54 s, decreasing as experience was gained. Thrombolysis in Myocardial Infarction trial (TIMI) flow grade increased from 2.6 +/- 0.8 to 3.0 +/- 0.0. Creatine kinase (CK) rose above normal in three patients (11.1%) exceeding 3x normal in one (3.7%) resulting in the diagnosis of non-Q-myocardial infarction. Particulate material was identified following 21 of 23 procedures suitable for analysis. Particle size was 204 +/- 57 microm in the major axis and 83 +/- 22 microm in the minor axis. Particles consisted predominantly of soft acellular atheromatous material, such as that typically found under a fibrous cap. Semiquantitative analysis suggested that the quantity of particulate material was less following stenting than following balloon dilation.

CONCLUSIONS

Particulate matter is commonly present following routine angioplasty and stenting of saphenous vein grafts. Containment, retrieval and analysis of this particulate debris are all feasible. Comparison to prior clinical experience is limited by small sample size. However, to the extent that these particles may contribute to distal embolization, no-reflow and infarction, such a system may contribute to the reduction of complications following vein graft intervention.

New method for placement of intracoronary stents in order to avoid their embolization in the intravascular space

Stent dislodgment from the delivery catheter is a well-known complication of angioplasty with stent implantation. The aim of our study was to investigate the feasibility, effectiveness, and safety of a new technique of intracoronary stent implantation in order to avoid stent loss in the intravascular space. Fifty consecutive patients were candidates for angioplasty and stent placement. During angioplasty, a technique was followed according to which the guide wire "hindered" the dislodgment of the stent from the balloon catheter. Successful angioplasty and stent placement were performed in 46 out of 50 patients (92% success rate). In three cases of failure of stent implantation, the stent moved onto the balloon catheter; however, this was impeded by the guide wire. One non-Q-wave myocardial infarction occurred. No major complications (Q-wave myocardial infarction, CABG, or death) were observed. In conclusion, the technique applied was feasible enough, safe, and effective. However, the appropriate modification of its "hardware" will render it even more feasible and user-friendly.

Predictors of acute and long-term outcome with transluminal extraction atherectomy: the New Approaches to Coronary Intervention (NACI) registry

The New Approaches to Coronary Intervention (NACI) registry was established to define the role of new coronary devices in overcoming the limitations of balloon angioplasty. The purpose of the present study was to evaluate the acute and long-term efficacy of the transluminal extraction catheter (TEC) device utilizing data from the NACI registry and identify clinical and anatomic patient subsets who may benefit from this device. From 1990-1994, >4,300 patients from 39 clinical sites enrolled consecutive patients treated with one of the 7 new devices to the NACI registry. The study population consists of 331 patients (385 lesions) treated with planned TEC as the sole new device. Of these patients, 243 (292 lesions) were treated for saphenous vein graft (SVG) disease and 88 (93 lesions) for native disease. Patients undergoing SVG treatment were older and more likely to be male. They had lower ventricular function, more unstable angina, and a higher incidence of congestive heart failure. Multivessel disease was more prevalent in the SVG cohort, as was evidence of thrombus before treatment. Although device success was achieved in 50% of SVG lesions and 41% of native lesions, lesion success was achieved in 90% and 78%, respectively, after adjunctive balloon angioplasty, and procedure success rates were 86% and 79%, respectively. The in-hospital major complication (death/Q-wave myocardial infarction/emergency coronary artery bypass graft [CABG] surgery) rate was higher in the SVG cohort (6.2% vs 2.3%), mainly due to higher mortality rate (5.3% vs 1.1%). Multivariate analysis showed that SVG was not an independent predictor for either an in-hospital major complication or clinical failure. The risk factors for major in-hospital complications were history of congestive heart failure (odds ratio = 3.17) and thrombus (odds ratio = 3.36). For clinical failure the risk factors were diabetes (odds ratio = 1.88), thrombus (odds ratio = 2.08), and calcium (odds ratio = 3.09). One-year rates of death, Q-wave myocardial infarction, or any repeat revascularization were 51% in the SVG cohort and 41% in the native cohort. Following adjustment, patients treated for SVG disease did not have a higher risk when compared with those treated for native disease. The factors significantly associated with this composite event at 1 year are male (relative risk = 1.41), patients with history of congestive heart failure (relative risk = 1.56), and total occlusions (relative risk = 1.52). This study shows that for both SVG and native cohorts, device success rates were low with TEC alone, but acceptable lesion success rates were achieved when adjunctive PTCA was used. In-hospital as well as 1-year major complications were higher in the SVG cohort. However, after adjusting for other risk factors, SVG attempt was not significantly associated with either in-hospital or 1-year events.

Transluminal extraction catheter atherectomy followed by immediate stenting in treatment of saphenous vein grafts

OBJECTIVES

The purpose of this study was to evaluate the effectiveness of transluminal extraction catheter (TEC) atherectomy followed by immediate Palmaz-Schatz coronary stenting of coronary bypass vein grafts.

BACKGROUND

Degeneration of saphenous vein coronary bypass grafts has become a common problem. Repeat bypass surgery is associated with greater risk and a poorer outcome than the initial operation. Moreover, percutaneous interventional procedures in vein grafts have been associated with high procedural complication rates, including distal embolization, and high restenosis rates. TEC atherectomy may reduce distal embolization, and stenting may reduce restenosis rates.

METHODS

We evaluated the procedural, hospital and clinical outcomes of TEC atherectomy followed by immediate Palmaz-Schatz coronary stenting of 53 vein grafts in 49 consecutive patients. The strategy was to limit instrumentation to extraction debulking and to stabilizing the site with stent deployment before using balloon dilation for optimal gain in lumen diameter.

RESULTS

Results are shown as mean value (95% confidence interval [CI]). The mean graft age was 9.2 years (95% CI 7.9 to 10.5), and 1.0 (95% CI 1 to 1) TEC cutter (2.2 mm [95% CI 2.1 to 2.3]) and 1.7 (95% CI 1.4 to 2.0) Palmaz-Schatz coronary stents/ vein graft were used. The procedural success rate was 98%, with a minimal lumen diameter at baseline of 1.3 mm (95% CI 1.1 to 1.5), increasing to 3.9 mm (95% CI 3.6 to 4.2) (p < 0.05) after the TEC-stent procedure. Procedural complications occurred infrequently: graft perforation in 1 (2%) of 53 patients and distal embolization in 1 (2%) of 53 (same patient). In-hospital complications included non-Q wave myocardial infarction in two patients and death after a successful procedure in three (6%) (n = 1 each: massive bleeding from the catheter site; sepsis; and acute myocardial infarction with asystole in the distribution of the stented vessel). The event-free survival rate to hospital discharge was 90%. Clinical follow-up (13 months [95% CI 11 to 15]) was available for all patients. There were five (11%) revascularization procedures (three bypass grafts and two percutaneous transluminal coronary interventions), four (9%) nonfatal myocardial infarctions and five (11%) deaths, for a cumulative rate of 28% for any adverse outcome occurring in 13 of 46 patients.

CONCLUSIONS

TEC atherectomy followed by immediate Palmaz-Schatz coronary stenting of stenoses in old (> 9 years) saphenous vein grafts can be successfully performed, with a low incidence of procedural and hospital complications. Clinical restenosis rates are low and less than those previously reported; however, late morbid cardiac events are still frequent in this high risk group of patients. These observational findings suggest that this technique may improve percutaneous management of vein graft disease, but optimal long-term management strategies remain to be determined.

Short- and long-term outcome of narrowed saphenous vein bypass graft: a comparison of Palmaz-Schatz stent, directional coronary atherectomy, and balloon angioplasty

Percutaneous treatment of saphenous vein graft (SVG) stenosis has been established as an alternative to repeat coronary artery bypass grafting. Intracoronary Palmaz-Schatz stent (PSS) and directional coronary atherectomy (DCA) have been suggested to provide better short- and long-term results than balloon angioplasty. Records of 840 patients with 931 SVG lesions treated with PSS (121 patients, 132 lesions), DCA (103 patients, 107 lesions), and balloon angioplasty (616 patients, 692 lesions) were reviewed. Inhospital and long-term outcome were compared among treated groups. The groups had similar clinical and angiographic baseline characteristics except for higher previously dilated grafts in the stent group and graft location among devices. Stent placement was angiographically successful in 99%, DCA in 95%, and balloon angioplasty in 93% of the lesions (p = 0.03). Quantitative angiography revealed a larger lumen diameter after procedure after PSS (3.2 mm) and DCA (3.1 mm) compared with 2.4 mm after balloon angioplasty (p = 0.0001). Angiographic complications (abrupt closure, severe dissections, or distal embolization) were evident in eight (6.1%) lesions after PSS placement, in 17 (15.9%) after DCA, and in 61 (8.8%) after balloon angioplasty. Serious in-hospital clinical complications (death, emergency coronary artery bypass grafting, or Q-wave myocardial infarction) were similar among devices. Survival rates were similar among the groups (p = 0.15). Repeat revascularization at follow-up was reported in 58 (60.4%) of patients after PSS, in 48 (51.1%) after DCA, and in 280 (49.4%) after balloon angioplasty. Correlates of additional revascularization at follow-up were older grafts, calcific lesions, previously dilated grafts, longer lesions, and patients with lower ejection fractions (odds ratio 1.06, 1.34, 1.43, 1.04, and 1.01, respectively). Correlates of mortality rate at follow-up were older patients, patients with lower ejection fractions, and distal embolization (odds ratio 1.04, 1.04, and 1.92, respectively). These data suggest that in patents with SVG stenosis the initial success and morbidity rates are similar when comparing PSS and DCA with balloon angioplasty. Although a larger lumen is obtained with PSS and DCA, patients who underwent balloon angioplasty had similar rates of cardiac events and requirements for additional procedures at follow-up.

Stenting the stent: alternative strategy for treating in-stent restenosis

Several approaches have been taken to relieve restenosis inside a vascular stent. In a patient with a complicated history of coronary artery disease, a restenotic lesion inside a Gianturco-Roubin flex stent was relieved by angioplasty and deployment of three 10 mm Palmaz P-104 "biliary" stents, with urokinase and verapamil used to prevent thromboembolism and the no-reflow phenomenon. An angiographic study 6 months later showed a patient graft with no residual stenosis.

Balloon catheter injury and vein graft morphology and function

Endovascular interventions to salvage failing vein bypass grafts are often associated with suboptimal outcomes. This study examines the effect of experimental vein graft catheter injury on vein graft morphology and vasomotor function. Thirty New Zealand white rabbits underwent a right common carotid interposition vein bypass graft. Ten grafts were harvested at 14 days, 10 were harvested at 28 days, and 10 had a balloon catheter injury induced at 14 days (4 F Fogarty catheter, 0.6 to 0.75 ml water inflation, 3 passes) and these 10 grafts were harvested after an additional 14 days. Morphologic and morphometric determinations (n = 5) or in vitro contractile studies (n = 5) were performed on segments of the vein grafts. Intimal thickness, without any intervention, increased by 84% from 14 to 28 days (p < 0.01), whereas catheter injury at 14 days induced a twofold increase (p < 0.001) in the formation of intimal hyperplasia by 28 days. Scanning electron microscopy demonstrated near-complete endothelial denudation after balloon catheter injury. In the 14- and 28-day control vein grafts, and in the balloon-injured vein grafts, the vascular surfaces had confluent endothelial linings. However, the ultrastructural features of the endothelial cells were group specific. Transmission electron microscopy of the same specimens confirmed this. There were no significant differences in contractility between the 28-day control and the catheter-injured vein grafts. This study demonstrates that balloon catheter injury doubles the rate at which intimal hyperplasia develops in vein grafts without significantly altering the physiologic phenotype of the smooth muscle cells as defined by their vasomotor function.

Transluminal extraction atherectomy for aortosaphenous vein graft stent restenosis

The optimal strategy to manage in-stent saphenous vein graft (SVG) restenosis has not been studied. We present two cases in which transluminal extraction atherectomy (TEC) was used successfully for the treatment of SVG stent restenosis. TEC atherectomy may provide an alternative to conventional balloon angioplasty for such patients.

Long-term clinical outcome after stent implantation in saphenous vein grafts

OBJECTIVES

We sought to determine the role of stent implantation in vein grafts by evaluating the long-term clinical outcome and estimated event-free survival at 5 years in 62 patients and by comparing our data with those of other treatment modalities previously reported.

BACKGROUND

Patients with recurrent angina after coronary artery bypass graft surgery pose a problem. Stent implantation has been advocated in an effort to avoid repeat operation and to address the limitations of balloon angioplasty.

METHODS

Patients undergoing stenting of a vein graft were entered into a dedicated data base. They were screened for death, infarction, bypass surgery and repeat angioplasty. Procedure-related events were included in the follow-up analysis. Survival and event-free survival curves were constructed by the Kaplan Meier method.

RESULTS

A total of 93 stents (84 Wallstent and 9 Palmaz-Shatz) were implanted in 62 patients. During the in-hospital period seven patients (11%) sustained a major cardiac event: two deaths (3%), two myocardial infarctions (3%) and three urgent bypass surgeries (5%). The clinical success rate, therefore, was 89%. During the follow-up period (median 2.5 years, range 0 to 5.9), another five patients (8%) died, 14 (23%) sustained a myocardial infarction, 12 (20%) underwent bypass surgery, and 14 (23%) underwent angioplasty. The estimated 5-year survival and event-free survival rates (free from infarction, repeat surgery and repeat angioplasty) were (mean +/- SD) 83 +/- 5% (95% confidence interval [CI] 73% to 93%) and 30 +/- 7% (95% CI 16% to 44%), respectively.

CONCLUSIONS

The in-hospital outcome of patients who underwent stent implantation in a vein graft is acceptable, but the long-term clinical outcome is poor. It is unlikely that mechanical intervention alone will provide a satisfactory or definite answer for the patient with graft sclerosis over the long term.

Excimer laser angioplasty vs. balloon angioplasty in saphenous vein bypass grafts: quantitative angiographic comparison of matched lesions

Technologies which ablate or debulk tissue may result in better angiographic outcomes by altering the elastic properties of the vessel wall. Accordingly, the procedural outcomes of 88 vein graft lesions treated by either excimer laser angioplasty with adjunct balloon angioplasty (PELCA + PTCA, n = 44) (Spectranetics CVX-300, 1.4-, 1.7-, or 2.0-MM catheters) or balloon angioplasty alone (PTCA, n = 44) were analyzed by quantitative angiography (Cardiac Measurement System). Lesions were individually matched for vessel position, reference diameter (RD), and minimal luminal diameter (MLD). Matching was deemed adequate as the preprocedure MLD (PELCA + PTCA, 1.14 +/- 0.48 mm; PTCA, 1.20 +/- 0.47 mm) and RD (PELCA + PTCA, 3.23 +/- 0.56 mm; PTCA, 3.25 +/- 0.57 mm) were not significantly different. There were also no significant differences between PELCA + PTCA- and PTCA-treated lesions with respect to patient age, graft age, lesion length, symmetry, and plaque area. Balloon diameter at maximal inflation was 2.77 +/- 0.55 mm (PELCA + PTCA group) and 2.84 +/- 0.59 mm (PTCA group), P = NS. Final MLD postprocedure was 2.17 +/- 0.54 mm and 2.19 +/- 0.55 mm for PELCA + PTCA- and PTCA-treated lesions (P = NS), respectively. Vessel stretch [(balloon diameter - MLD pre)/RD], elastic recoil [(balloon diameter - MLD post)/RD], and acute gain [(MLD post - MLD pre)/RD] were calculated and normalized for vessel size (RD). Vessel stretch (PELCA + PTCA, 0.60 +/- 0.22; PTCA, 0.59 +/- 0.24; P = NS), elastic recoil (PELCA + PTCA, 0.28 +/- 0.18; PTCA, 0.26 +/- 0.16), and acute gain (PELCA + PTCA, 0.34 +/- 0.24; PTCA, 0.31 +/- 0.23; P = NS) were not significantly different between the two treatment groups. In a matched population of successfully treated vein graft lesions, PELCA + PTCA did not reduce elastic recoil or improve immediate angiographic outcome, as compared with PTCA alone.

Recanalization of totally occluded saphenous vein grafts using local urokinase delivery with the Dispatch catheter

Current techniques for the percutaneous revascularization of totally occluded vein grafts are limited by a low initial success rate, a significant incidence of distal embolization, and a high rate of early graft reclosure. This case report describes two patients in whom graft recanalization was attempted with the combined use of balloon angioplasty/intra-graft stent placement and local urokinase delivery using a new angiotherapy catheter. Successful recanalization was achieved in both patients without major complications, in spite of a large thrombus burden as demonstrated by angiography.

Post-stenting enlarging false aneurysm of a saphenous vein graft

Stenting seems to be a definitive procedure after failed balloon coronary angioplasty. This report describes a case of redo coronary bypass grafting and concomitant resection of enlarging false aneurysm of a saphenous vein graft that developed secondary to stenting for recurrent stenosis after serial percutaneous transluminal coronary angioplasty. It warns us of a pitfall in catheter intervention in an aged saphenous vein graft.

Immediate results and late outcomes after stent implantation in saphenous vein graft lesions: the multicenter U.S. Palmaz-Schatz stent experience. The Palmaz-Schatz Stent Study Group

OBJECTIVES

This study reports the multicenter registry experience evaluating the safety and efficacy of the Palmaz-Schatz stent in the treatment of saphenous vein graft disease.

BACKGROUND

Saphenous vein graft angioplasty is associated with frequent periprocedural complications and a high frequency of restenosis. Stent implantation has been shown to reduce restenosis, with improved long-term outcomes in the treatment of native coronary artery disease. Preliminary experience with stent placement in the treatment of saphenous vein graft lesions has been favorable.

METHODS

Twenty U.S. investigator sites enrolled a total of 589 symptomatic patients (624 lesions) for treatment of focal vein graft stenoses between January 1990 and April 1992. Follow-up angiography was performed at 6 months, and the clinical course of all study patients was prospectively collected at regular intervals for up to 12 months.

RESULTS

Stent delivery was successful in 98.8% of cases, and the procedural success rate was 97.1%. The lesion diameter stenosis decreased from 82 +/- 12% (mean +/- SD) before to 6.6 +/- 10.2% after treatment. Major in-hospital complications occurred in 17 patients (2.9%); stent thrombosis was found in 8 (1.4%); and major vascular or bleeding complications were noted in 83 (14.3%). Six-month angiographic follow-up revealed an overall restenosis rate (> or = 50% diameter stenosis) of 29.7%. Multivariate logistic regression analysis indicated that 1) restenotic lesions, 2) smaller reference vessel size, 3) history of diabetes mellitus, and 4) higher percent poststent diameter stenosis were independent predictors of restenosis. The 12-month actuarial event-free survival was 76.3%.

CONCLUSIONS

Stent implantation in patients with focal saphenous vein graft lesions can be achieved with a high rate of procedural success, acceptable major complications, reduced angiographic restenosis and favorable late clinical outcome compared with historical balloon angioplasty control series. The rigorous anticoagulation regimen after stent placement results in more frequent vascular and other bleeding complications. Future randomized studies comparing standard balloon angioplasty with stent implantation are warranted to properly assess the full impact of stent placement in the treatment of saphenous vein graft lesions.

Predictors and sequelae of distal embolization during saphenous vein graft intervention from the CAVEAT-II trial. Coronary Angioplasty Versus Excisional Atherectomy Trial

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 > or = 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.

A novel approach to the placement of Palmaz-Schatz biliary stents in saphenous vein grafts

The placement of Palmaz-Schatz biliary stents has become a successful method to treat stenoses in large saphenous vein grafts. Unlike coronary stents, the biliary stents are not routinely delivered with a selective delivery sheath and may be more difficult to deliver and prone to detachment from the balloon and even embolization during delivery. In order to enhance the ability to deliver these stents, a guide-within-a-guide system was developed. A 7F guiding catheter was used as a selective delivery sheath within a standard guiding catheter. Nineteen biliary stents were successfully placed in vein grafts in 15 patients using this system. One procedure was complicated by an embolic event documented angiographically following intragraft delivery of urokinase but prior to stent implantation.

Early and late quantitative angiographic results of vein graft lesions treated by excimer laser with adjunctive balloon angioplasty

BACKGROUND

Percutaneous excimer laser coronary angioplasty (PELCA) has been approved for treatment of diseased saphenous vein bypass grafts. However, detailed and complete quantitative angiographic analysis of immediate procedural and late follow-up results has not been performed.

METHODS AND RESULTS

PELCA using the CVX-300 excimer laser system was performed in 125 bypass lesions (mean graft age, 96 +/- 53 months; range, 2 to 240 months) in 106 consecutive patients at eight centers. Quantitative analyses of the procedural and follow-up angiograms were done with the Cardiac Measurement System. Stand-alone PELCA was done in 21 lesions (17%). Lesions were located at the ostium (20%), body (67%), or distal anastomosis (13%). The graft reference diameter was 3.26 +/- 0.79 mm (mean +/- SD). Minimal lumen diameter increased from 1.09 +/- 0.52 mm before treatment to 1.61 +/- 0.69 mm after laser and 2.18 +/- 0.63 mm after adjunctive balloon dilation (P < .001) but had declined at follow-up to 1.40 +/- 1.17 mm. Dissections were evident in 45% of lesions after laser treatment (types A and B, 27%; types C through F, 18%), including 7% occlusions. Angiographic success (< or = 50% diameter stenosis [% DS]) was 54% after laser and 91% after adjunctive PTCA, with an overall clinical success rate of 89%. In-hospital complications were death, 0.9%; myocardial infarction (Q-wave and non-Q-wave), 4.5%; and bypass surgery, 0.9%. Independent predictors of % DS after laser were reference diameter, lesion length, and minimal lumen diameter before laser. At angiographic follow-up in 83% of eligible patients, the restenosis rate per lesion (DS > 50%) was 52%, including 23 occlusions (24%). The only independent predictor of increased % DS at follow-up was lesion symmetry. Logistic regression indicated that smaller reference diameter was an independent predictor of late occlusion. Overall 1-year mortality was 8.6%. Actuarial event-free survival (freedom from death, myocardial infarction, bypass surgery, or target vessel percutaneous transluminal coronary angioplasty) was 48.2% at 1 year.

CONCLUSIONS

Excimer laser angioplasty with adjunctive balloon angioplasty can be safely and successfully performed in diseased, old saphenous vein bypass graft lesions considered at high risk for reintervention. The extent of laser ablation remains limited by the diameter and effectiveness of the catheters. Late restenosis and, in particular, total occlusion mitigate the early benefits of the procedure. Other approaches such as the routine use of additional anticoagulation (eg, warfarin) should be considered to reduce the risk of late occlusions and restenosis after laser angioplasty of bypass grafts.

A multicenter, randomized trial of coronary angioplasty versus directional atherectomy for patients with saphenous vein bypass graft lesions. CAVEAT-II Investigators

BACKGROUND

Directional coronary atherectomy and percutaneous transluminal coronary angioplasty have both been used in symptomatic patients with coronary saphenous vein bypass graft stenoses. The relative merits of plaque excision and removal versus balloon dilatation remain uncertain. We compared outcomes after directional coronary atherectomy or angioplasty in patients with de novo bypass graft stenoses.

METHODS AND RESULTS

Fifty-four North American and European sites randomized 305 patients with de novo vein graft lesions to atherectomy (n = 149) or angioplasty (n = 156). Quantitative coronary angiography at a core laboratory assessed initial and 6-month results. Initial angiographic success was greater with atherectomy (89.2% versus 79.0%), as was initial luminal gain (1.45 versus 1.12 mm, P < .001). Distal embolization was increased with atherectomy (P = .012), and a trend was shown toward more non-Q-wave myocardial infarction (P = .09). Although the 6-month net minimum luminal diameter gain was 0.68 mm for atherectomy and 0.50 mm for angioplasty, the restenosis rates were similar, 45.6% for atherectomy and 50.5% for angioplasty (P = .491). At 6 months, there was a trend toward decreased repeated target-vessel interventions for atherectomy (P = .092); in addition, 13.2% of patients treated with atherectomy versus 22.4% of the angioplasty patients (P = .041) required repeated percutaneous intervention of the initial target lesion.

CONCLUSIONS

Atherectomy of de novo vein graft lesions was associated with improved initial angiographic success and luminal diameter but also with increased distal embolization. There was no difference in 6-month restenosis rates, although primary atherectomy patients tended to require fewer target-vessel revascularization procedures.

Follow-up patency of side branches covered by intracoronary Palmaz-Schatz stent

To assess the risk of late side branch occlusion after Palmaz-Schatz stent deployment, we analyzed the angiographic evolution of 62 patients treated by successful stent implantation who had a total of 85 side branches starting from the stented segment. Side branches were considered minor (n = 39) when the diameter was < 1 mm and intermediate (n = 46) when the vessel had > or = 1 mm diameter. One angiographic follow-up study was available in all patients at 8 +/- 5 months. Eight minor branches presented some degree of stenosis at origin before stent deployment (4 totally occluded). After stent deployment, 32 (82%) of 39 remained unchanged and 3 became occluded. Late progression at origin occurred in 4 of 34 (3 occluded). Before stent deployment, 48% of the intermediate branches had some compromise degree at their starting point (1 totally occluded). Eight of 45 intermediate branches became occluded after stent implantation. Late progression at origin happened in 5 of 32 branches (2 occluded). Some degree of follow-up stenosis regression at the origin was observed in 22 (26%) of 85 arteries. Neither clinical nor angiographic factors could be identified as predictors of late side branch occlusion or stenosis progression at its origin. Later occlusion or progression at origin of a side branch covered by a Palmaz-Schatz stent seems to be an uncommon occurrence (7% and 12% respectively) that cannot be predicted by angiographic or clinical factors. On the contrary, regression at follow-up of a side branch-origin stenosis can also come about.

Comparison of clinical and angiographic outcomes after saphenous vein graft angioplasty using coronary versus 'biliary' tubular slotted stents

BACKGROUND

Saphenous vein graft (SVG) angioplasty using 15-mm articulated, tubular slotted stents results in low (0% to 20%) residual diameter stenoses and infrequent (< 5%) major complications. A "biliary" stent design with greater radial compressive strength, enhanced visibility, and more variable sizing (diameter and length) has been approved for noncoronary indications. A comparison of outcomes after coronary versus biliary stent placement in SVG stenoses has not been performed. The purpose of this study was to compare the angiographic and clinical results after SVG angioplasty using these two balloon-expandable, tubular slotted stent designs.

METHODS AND RESULTS

During a 3-year period, 231 patients with 305 SVG lesions were treated using Palmaz-Schatz coronary (n = 108) or biliary (n = 123) stents. Cineangiograms were reviewed using qualitative morphological and quantitative angiographic methods. Time-dependent clinical outcome (freedom from death, Q-wave myocardial infarction, or the need for repeat coronary bypass surgery or SVG angioplasty) was assessed using Kaplan-Meier life-table methods. Unstable angina (P < .001) and recent myocardial infarction (P = .001) were present more often in patients undergoing biliary stent versus coronary stent placement. Biliary stent-treated SVG lesions were more frequently de novo (P = .001), ostial in location (P = .002), > or = 10 mm in length (P = .009), thrombus containing (P = .001), and ulcerated (P < .001) than coronary stent-treated SVG lesions. Angiographically, biliary stent-treated lesions had larger reference vessel diameter (3.43 +/- 0.59 mm versus 3.10 +/- 0.64 mm, P < .001), higher balloon-to-artery ratio (1.15 +/- 0.16 mm versus 1.07 +/- 0.19, P = .0001), and lower residual diameter stenosis (6 +/- 17% versus 14 +/- 11% in coronary stent-treated patients; P < .001). Procedural success rates were high (95%), in-hospital major complications were uncommon (< 3%), and follow-up clinical outcomes were favorable (6-month event-free survival approximately 80%) in both groups.

CONCLUSIONS

Despite frequent short-term ischemic syndromes and unfavorable lesion characteristics, both biliary and coronary cohorts have similarly favorable short-term procedural results and long-term clinical outcomes. The increased strut thickness of the biliary stent confers greater fluoroscopic visibility and radial compressive strength in exchange for decreased stent flexibility and added technical demand in stent deployment. Extreme caution is recommended with biliary stent placement in the treatment of SVG lesions as clinical results are highly operator dependent.

Long-term angiographic and clinical outcome after implantation of balloon-expandable stents in aortocoronary saphenous vein grafts

Balloon angioplasty of aortocoronary saphenous vein graft lesions is associated with high restenosis and clinical event rates. The goal of this multicenter study was to assess long-term angiographic and clinical outcome of patients electively treated with single Palmaz-Schatz stents in aortocoronary saphenous vein grafts. In 198 patients (209 lesions), elective placement of single Palmaz-Schatz stents was attempted. Angiography was performed at baseline, immediately after stent placement, and at 6-month follow-up. Stent placement was successful in 98.5% of patients. One patient (0.5%) had stent thrombosis. Restenosis occurred in 34% (45 of 133) of the restudied lesions. Restenosis was lower in de novo lesions than in restenotic lesions (22% vs 51%, p < 0.001). Ostial lesions had a higher restenosis rate than nonostial lesions (61% vs 28%, p = 0.003). Freedom from death, myocardial infarction, coronary artery bypass surgery, and repeat angioplasty was present in 70% of patients. Eighty-two percent of patients with de novo lesions remained event-free at 1 year, whereas only 55% of patients with prior angioplasty were event-free at 1 year (p < 0.001). The use of the Palmaz-Schatz stent for the treatment of focal, de novo, aortocoronary saphenous vein graft lesions is associated with a high procedural success rate, a low angiographic restenosis rate, and low clinical event rates, including the need for repeat revascularization. The results of this study need validation by a prospective randomized trial comparing stent implantation with angioplasty.

Comparison of three coronary stents: clinical and angiographic outcome after elective placement in 134 consecutive patients

One hundred and thirty-four consecutive patients undergoing elective coronary stenting were studied to assess the relative performance of Palmaz-Schatz (PS), Gianturco-Roubin (GR), and Wiktor (W) stents. Eighty-six percent of patients underwent follow-up angiography. Initial and follow-up angiograms were assessed by a central angiographic core laboratory. Attempts were made to place 81 Palmaz-Schatz (PS) stents, 21 Gianturco-Roubin (GR), and 32 Wiktor (W) stents. PS stents were less frequently successfully deployed (88% PS vs. 100% GR vs. 97% W; P = 0.03). The final percent stenosis was greater with the GR stent (32% GR vs. 14% PS vs. 19% W; P < 0.001). The restenosis rate was lower in the PS group (PS 48.2% vs. GR 66.7% and W 68.4%; P = 0.044). After accounting for the effect of prior restenosis (P = 0.005) and saphenous vein site (P = 0.006) in multivariate testing, lesion severity at follow-up was still less with the Palmaz-Schatz stent (P = 0.037).

Elevation of the creatine kinase myocardial isoform following otherwise successful directional coronary atherectomy and stenting

Moderate elevation of creatine kinase (CK) MB isoform is common following otherwise successful percutaneous coronary revascularization, and is frequently interpreted as evidence of a non-Q-wave myocardial infarction. It is not clear, however, whether elevation of CK MB isoform carries sufficient adverse clinical impact to be categorized as a "major" complication. We therefore explored the incidence and clinical consequence of elevation of CK MB isoform in a consecutive series of 565 patients who had otherwise successful directional coronary atherectomy (n = 274) or stenting (n = 291), and were followed for a mean of 2 years. Of this cohort, 11.5% had postprocedure elevation of the CK MB isoform above normal (10 IU/liter). These patients tended to be older and to have undergone atherectomy of a de novo lesion with adverse morphology (thrombus, calcification, eccentricity). Patients with elevation of CK MB isoform following otherwise successful revascularization generally showed no adverse long-term sequelae (death, recurrent myocardial infarction, repeat revascularization) compared with patients without elevation of CK MB isoform. Only 2.3% of the patients who had CK MB isoform release > 50 IU/liter demonstrated a trend (p = 0.08) toward decreased late survival, compared with patients without CK MB isoform elevation. While minor CK MB isoform elevation is common (11.5%) after successful coronary stenting or directional atherectomy, it generally has no adverse clinical consequences, and should not be considered a major complication.(ABSTRACT TRUNCATED AT 250 WORDS)

Peripheral vascular complications of directional coronary atherectomy and stenting: predictors, management, and outcome

The hospital course of 688 patients consecutively treated with directional coronary atherectomy (375 procedures) or Palmaz-Schatz stenting (376 procedures) was evaluated to identify incidence, predictors, and outcome of major vascular complications. Major vascular complications (defined as surgical repair, major hematoma, or bleeding with a > 10-point hematocrit decrease requiring transfusion alone, or nonsurgically managed arteriovenous fistula, pseudoaneurysm, retroperitoneal hematoma or femoral neuropathy) occurred in 11.7% of procedures, and were more common after stenting than after directional coronary atherectomy (16.8% vs 6.7%, p < 0.001). In particular, surgical repair was required after 10.1% of stenting procedures, versus 5.1% of directional coronary atherectomies (p < 0.02). Multivariable analysis identified age > 70 years, coronary stenting, female gender, multiple procedures during the index hospitalization, and a low nadir platelet count as independent predictors of major vascular complications (all p < 0.03). In the stent subgroup, excessive anticoagulation, nadir platelet count, hypertension, and sheath removal protocol (other than a same-day, activated clotting time-guided protocol) were all independent predictors of vascular complications. Thus, the overall risk of vascular complications with new device procedures (stenting, directional atherectomy) is greater than that traditionally seen with balloon angioplasty alone, and is determined by patient-related factors, procedure type, and management parameters.

Predictors of outcome of percutaneous excimer laser coronary angioplasty of saphenous vein bypass graft lesions. The Percutaneous Excimer Laser Coronary Angioplasty Registry

A total of 495 patients underwent treatment with excimer laser angioplasty for 545 saphenous vein graft stenoses. Clinical success was achieved in 455 of 495 patients (92%), as indicated by < or = 50% residual stenosis at every target lesion and no complication during hospitalization. At least 1 in-hospital complication occurred in 30 of 495 patients (6.1%): death (1.0%), bypass surgery (0.6%), and Q-wave (2.4%) or non-Q-wave (2.2%) myocardial infarction. Relative risk analysis showed that ostial lesions (n = 65) tended to have higher clinical success (success rate = 95%, adjusted odds ratio [OR] = 2.1 [95% confidence interval (CI) 0.62, 6.88]; p = 0.24) and lower complications (complication rate = 0%, OR = 0.10 [CI 0.01, 0.79]; p = 0.03) than lesions in the body of the vein graft. Lesions > 10 mm (n = 131) had lower success (success rate = 84%, OR = 0.30 [CI 0.16, 0.56]; p = 0.001) and higher complications (complication rate = 12%, OR = 3.3 [CI 1.6, 6.6]; p = 0.004) than discrete lesions. Lesions in small vein grafts < 3.0 mm (n = 76) tended to have increased success (success rate = 94%, OR = 1.55 [CI 0.70, 3.44]; p = 0.39) and lower complications (complication rate = 2.2%, OR = 0.31 [CI 0.10, 0.94]; p = 0.03). Thus, excimer laser-facilitated angioplasty has the most favorable outcome for discrete lesions located at the ostium of all grafts and in the body of smaller saphenous vein grafts.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of prior coronary restenosis on the risk of subsequent restenosis after stent placement or directional atherectomy

Lesions that have developed restenosis after a prior intervention may be more likely to develop restenosis after subsequent percutaneous interventions. To determine if this is an independent effect, the clinical characteristics and immediate angiographic outcomes of 179 prior restenosis lesions were compared with those of 254 primary lesions after stenting or directional atherectomy. Six-month angiographic follow-up was obtained for 79% of successfully treated lesions. Univariable and multivariable logistic regression was used to determine how binary restenosis (defined as > or = 50% diameter stenosis at follow-up) was influenced by postprocedure luminal diameter, left anterior descending artery location, diabetes mellitus, as well as prior restenosis. At 6-month follow-up, prior restenosis lesions had a significantly smaller late diameter (1.77 vs 2.18 mm, p < 0.001), more absolute late loss (1.35 vs 1.14 mm, p = 0.051), a higher loss index (0.58 vs 0.45, p < 0.02), and a higher binary restenosis rate (37.3% vs 24.4%, p = 0.01). Whereas univariable analysis revealed that left anterior descending artery location, diabetes mellitus, postprocedure luminal diameter < 3.1 mm, and prior restenosis were each strong predictors of binary restenosis (all p < 0.02), multivariable analysis showed that after adjustment for left anterior descending artery location, diabetes, and postprocedure luminal diameter, prior restenosis was no longer an independent predictor of restenosis (odds ratio 1.57, 95% confidence interval 0.95-2.60, p = 0.073). In conclusion, although prior restenosis lesions do show more restenosis than primary lesions, much of this effect is due to preselection of a population enriched in other known factors that predispose to restenosis.

Clinical significance of distal embolization after transluminal extraction atherectomy in diffusely diseased saphenous vein grafts

Standard balloon angioplasty of degenerated saphenous vein graft lesions may be complicated by distal embolization, particularly in the presence of intragraft thrombus. Transluminal extraction atherectomy may be useful in this setting because of its ability to remove particulate debris. This study was designed to identify the incidence and prognostic significance of distal embolization after transluminal extraction atherectomy in high-risk saphenous vein graft lesions. To address these issues the clinical course of 65 consecutive patients (86 high-risk saphenous vein graft lesions) was reviewed after extraction atherectomy. Distal embolization occurred in 11 (12.8%) of 86 high-risk lesions. The majority (63.6%) of these episodes occurred after adjunct balloon dilatation following uncomplicated use of the extraction atherectomy catheter. Correlates of distal embolization included patient age and the presence of intragraft thrombus. Major in-hospital complications developed more often in patients with distal embolization (46% vs 2% in those without distal embolization, p < 0.001), resulting in a reduced procedural success rate in this group (55% vs 91%, p = 0.01). We conclude that the risk of distal embolization after saphenous vein graft angioplasty, although potentially reduced, is not eliminated with transluminal extraction atherectomy, particularly in lesions with superimposed thrombus.

Endoluminal stenting of narrowed saphenous vein grafts: long-term clinical and angiographic follow-up

From April 1986 through April 1993, 58 intracoronary stents (41 Wall and 17 Wiktor stents) were implanted for the treatment of saphenous vein graft stenosis in 40 symptomatic patients. The indication was a primary stenosis in 44 and restenosis in 14 procedures. In-hospital complications were subacute stent thrombosis (2%), myocardial infarction (2%), and emergency coronary artery bypass grafting (CABG) (2%). Complications during a mean follow-up period of 42+/-27 months were restenosis (35% by patient, 33% by lesion), myocardial infarction (12%), late bypass grafting (12%), and death (7%). On quantitative coronary angiographic analysis, the mean minimal luminal diameter (and its confidence interval) increased from 1.3 mm (1.1-1.5 mm, preprocedure) to 2.9 mm (2.7-3.1 mm, postprocedure) and 2.2 mm (2.0-2.5 mm, 6 months follow-up, 95% angiographic follow-up). Progression of the underlying coronary artery disease and restenosis were the main reasons for a continual decline of the proportion without cardiac event on a Kaplan-Meier estimate. Restenosis occurred in one-third of cases beyond the first 6 months of follow-up. A relative risk ratio analysis for restenosis, performed on 14 variables, disclosed an increased risk for the following variables: (1) stenting of the proximal, distal or anastomosis part of the vein graft (relative risk 2.41, confidence interval: 1.28-3.59), (2) the implantation of stents < 4.5 mm (2.59, 1.18-4.00), and (3) stenting of a redo-CABG vein graft (2.37, 1.17-3.58). Saphenous vein graft stenting seems to be characterized by excellent immediate clinical and angiographic results; in particular, stent thrombosis is rare.(ABSTRACT TRUNCATED AT 250 WORDS)

Palmaz-Schatz stenting for treatment of focal vein graft stenosis: immediate results and long-term outcome

OBJECTIVES

This study aimed to evaluate the effectiveness of Palmaz-Schatz stenting for the treatment of saphenous vein graft stenoses.

BACKGROUND

Failure of saphenous vein grafts is a common cause of recurrent ischemia after coronary bypass surgery. A second bypass surgery carries more risk than the initial procedure, and balloon angioplasty of vein grafts has yielded disappointing results. It has been hoped that stenting might offer a better treatment option.

METHODS

We examined the results of stent placement in 200 saphenous bypass graft lesions consecutively treated with either coronary (n = 146) or biliary (n = 54) Palmaz-Schatz stents. Immediate outcome and clinical follow-up (median 15.5 months) were examined in all patients. To document angiographic outcome, a second angiography was performed at 3 to 6 months for the first 120 consecutively stented lesions and was successfully obtained for 94 (78%).

RESULTS

The mean graft age (+/- SD) was 8.7 +/- 4 years. Stent placement was successful in 197 (98.5%) of 200 lesions, reducing the mean diameter stenosis from 74 +/- 14% to 1 +/- 15%. In 164 procedures, there was one in-hospital death (0.6%), no emergency bypass operations and no Q wave myocardial infarctions. There was one acute stent thrombosis (0.6%) but no subacute thromboses. Vascular repair was required after 14 procedures (8.5%), with transfusion in 23 additional cases (14%). Angiographic restenosis (diameter stenosis > or = 50%) at 3- to 6-month follow-up was 17% (95% confidence interval 9% to 25%). By Kaplan-Meier estimates, however, the 2-year second revascularization rate was 49%, reflecting the predominant revascularization performed to treat progressive disease at other sites because failure at the stented site occurred in only 22% of lesions.

CONCLUSIONS

Stenting resulted in excellent immediate and long-term angiographic results in this group of focally diseased, older saphenous vein grafts. Despite the high immediate success and very low (17%) angiographic restenosis rate at 6 months, approximately one half of these patients required further revascularization in the following 2 years, mainly because of disease progression at other sites.

Initial and long-term outcome of 83 patients after balloon angioplasty of totally occluded bypass grafts

OBJECTIVES

This study was designed to evaluate the safety and short- and long-term results of coronary angioplasty of totally occluded bypass grafts in patients with clinical conditions other than acute myocardial infarction.

BACKGROUND

Total occlusion of bypass grafts after coronary artery surgery often causes recurrent ischemia. The safety and results of percutaneous transluminal coronary angioplasty in occluded bypass grafts are controversial.

METHODS

All patients with dilation of a totally occluded bypass graft attempted between 1981 and 1991 were retrospectively identified from a data base. Patients treated in the setting of an acute myocardial infarction were excluded. Eighty-three patients met these criteria and constitute the study group. Hospital records, office charts and procedural reports were reviewed in all patients to supplement details available in the data base.

RESULTS

The time from bypass surgery to attempted coronary angioplasty ranged from 1 to 226 months (mean time 88 months). The mean (+/- SD) duration of graft occlusion was 31 +/- 46 days (range 1 to 180). In 27 attempts the bypass graft was the only site dilated, and in 56 attempts (68%) one to six other sites (n = 101) were dilated. Angiographic success (< or = 40% residual lumen stenosis) was achieved in 61 grafts (73%) and 98 of the additional sites (97%) (p < 0.001). Major complications included one procedural death and two Q wave infarctions. Follow-up for a mean of 32 months demonstrated a 1- and 3-year actuarial survival rate of 94% and 80%, respectively. At 3 years, only 34% of patients were free of repeat angioplasty or surgery.

CONCLUSIONS

Angioplasty of totally occluded bypass grafts can be successful in the majority of selected patients, although major complications can occur. Strategies for sustained patency are needed to improve the long-term results.

Acute results and long-term outcome of transluminal extraction catheter atherectomy for saphenous vein graft stenoses

Distal embolization of atheroma and thrombus is a major concern when performing balloon angioplasty in coronary saphenous vein grafts (SVGs). The transluminal extraction catheter (TEC) is designed to remove this material and may improve the safety of percutaneous treatment of SVG disease. We assessed the acute results and long-term outcome of 67 patients (mean age 65.6 +/- 8.1 years; range 47-83 years) who underwent 73 separate TEC atherectomy procedures. Eighty-eight SVG lesions were treated (mean age 8.7 +/- 3.8 years from bypass surgery). Procedural success (< 50% final diameter stenosis and absence of major complications) was obtained in 63 patients (86%). Adjunctive balloon angioplasty and/or directional coronary atherectomy was required in 69 of the procedures (95%). Major complications, occurring in 8 patients (11%), were acute closure in 4 (5%), resulting in Q-wave myocardial infarction in 3 and urgent bypass surgery in 1, and distal embolization in 4 (5%; 1 associated with Q-wave myocardial infarction). Angiographic follow-up was available for 50 patients and restenosis was present in 26 (52%). These data suggest TEC atherectomy can be performed in SVGs with an acceptable procedural risk, but restenosis remains a significant limitation which will require other strategies to overcome.

Clinical and angiographic results of transluminal extraction coronary atherectomy in saphenous vein bypass grafts

BACKGROUND

Transluminal extraction coronary (TEC) atherectomy is a relatively new device that has recently been approved by the Food and Drug Administration. Because of its ability to aspirate clot and atheromatous material, TEC atherectomy may be useful in patients with stenoses in saphenous vein bypass grafts.

METHODS AND RESULTS

TEC atherectomy was performed on 158 saphenous vein graft lesions in 146 consecutive patients with a mean age of 65 +/- 8 years (78% men). Clinical indications for atherectomy included stable angina (37%), unstable angina (54%), and postinfarction angina after recent (< 1 month) myocardial infarction (8%). Patients with acute myocardial infarction and target vessels < 2 mm in diameter were excluded. The mean age of the bypass graft was 8.3 +/- 3.0 years, and 17% were diffusely diseased and degenerated. Complex lesion morphology included total occlusion (6%), eccentricity (64%), ulceration (18%), and thrombus (28%). The TEC atherectomy cutter was successfully advanced through 144 lesions (91%), but technical failures occurred in 14 lesions (9%), and these were subsequently managed by successful balloon angioplasty. Quantitative angiography revealed an increase in lumen diameter from 0.9 +/- 0.5 mm, to 1.5 +/- 0.7 mm after TEC atherectomy, to 2.3 +/- 0.8 mm after percutaneous transluminal coronary angioplasty (PTCA) (P < .001), which corresponded to decreases in diameter stenosis from 75 +/- 14%, to 58 +/- 20% after TEC atherectomy, to 36 +/- 22% after PTCA (P < .001). Device success was achieved in 39.2% (post-TEC atherectomy decrease in diameter stenosis > or = 20%), and procedural success was achieved in 84% (final diameter stenosis < 50% in the absence of a major complication). Angiographic complications were evident in 33 lesions (20.7%) immediately after TEC atherectomy and in 8 lesions (5%) after PTCA, including distal embolization (11.9%), no-reflow (8.8%), and abrupt closure (5.0%), but no perforations. Adjunctive PTCA (and other medical therapy) successfully managed 61% of angiographic complications. Serious clinical complications included in-hospital death in 3 patients (2.0%), emergency bypass surgery in 1 patient who died (0.7%), Q wave myocardial infarction in 3 patients (2.0%), non-Q wave myocardial infarction in 4 patients (2.7%), vascular injury requiring surgical repair and/or blood transfusion in 9 patients (6.1%), and hemorrhagic cerebral infarction in 4 patients (2.7%). Using a composite clinical end point defined as in-hospital death, emergency bypass surgery, or myocardial infarction, the strongest independent correlate (P < .001) of a severe clinical complication was the development of one or more serious angiographic complications (no-reflow, distal embolization, or abrupt closure) immediately after TEC atherectomy. Complete clinical follow-up was available in 118 (92%) of 128 eligible patients at an interval of 6.0 +/- 2.5 months after discharge. Late cardiac outcome included recurrent angina treated with medical therapy (18%), repeat percutaneous intervention on the original target lesion (26%), repeat coronary artery bypass surgery (5%), Q wave myocardial infarction (4%), and late cardiac death (7%). Angiographic follow-up in 105 (80%) of 132 eligible lesions revealed a restenosis rate of 69% (defined as a diameter stenosis > 50%), including 30 lesions (29%) with total occlusion of the original lesion.

CONCLUSIONS

In patients with stenoses in saphenous vein bypass grafts, TEC atherectomy is limited by the frequent need for adjunctive balloon angioplasty to achieve adequate lumen enlargement and to manage TEC atherectomy-induced complications. Although the incidence of serious clinical complications is similar to that of other percutaneous interventions in vein grafts, there is a high incidence of restenosis and late vessel occlusion. Prospective randomized studies are needed to determine the best revascularization strategy for high-risk patients with old degenerated vein

Directional coronary atherectomy of saphenous vein graft narrowings: multicenter investigational experience

Directional coronary atherectomy (DCA) of saphenous vein graft lesions was performed at 21 centers between June 1988 and September 1990, which represents the multicenter investigational experience. A total of 318 procedures were performed and 363 vein graft lesions were treated. Angiographic success with DCA was achieved in 86% of lesions and clinical success was achieved in 85% (269 of 318) of patients. Major complications occurred in 2.5% of patients, with Q wave myocardial infarction (MI) in 1.3%, death in 0.9%, and urgent bypass surgery in 0.9%. Other complications included non-Q wave MI in 4.4%, distal embolization in 7.2%, coronary occlusion in 1.9%, and vessel perforation in 0.6%. Although there was a trend toward lower success rates with ostial vein graft lesions (82% vs 88% for other graft sites) and with diffuse (length > 20 mm) graft lesions (75% vs 87% for shorter lesions), the differences were not significant. Baseline clinical and angiographic factors did not identify predictors of lower success or more frequent complications in the study group. Overall restenosis rate in the 149 patients with angiographic restudy was 57%. The restenosis rate was significantly lower with primary vein graft lesions (38%) compared with a 75% restenosis rate for grafts with prior restenosis, p < 0.001. This initial multicenter investigational experience indicates that directional coronary atherectomy is a safe and effective therapy for selected saphenous vein graft disease. Although the overall restenosis rate is relatively high, the restenosis rate following DCA of primary vein graft lesions is significantly lower than for vein grafts having had prior intervention.(ABSTRACT TRUNCATED AT 250 WORDS)

Complications of directional coronary atherectomy: incidence, causes, and management

An assessment of complications is essential to the evaluation of directional coronary atherectomy. Major complications--such as death, Q wave myocardial infarction, or the need for emergency bypass surgery to correct acute vessel closure--result from a variety of familiar mechanisms, including dissection, thrombosis, or guiding catheter injury. In addition, unique complications of this device, such as catheter nose cone injury or vascular perforation, may also result in severe ischemia. With prompt recognition of the cause, most ischemic complications can be successfully treated in the catheterization laboratory. Less severe complications, such as femoral vascular injury, also require recognition and appropriate treatment in order to minimize sequelae. Although several large series have now documented that the overall incidence of atherectomy complications appears similar to that reported for conventional balloon angioplasty, no direct comparisons can be made until randomized trials (such as Coronary Angioplasty Versus Excisional Atherectomy Trial [CAVEAT]) are analyzed, to control for potential demographic or lesion-specific influences on complication rates.

Experience with directional coronary atherectomy since pre-market approval

Directional coronary atherectomy (DCA) received Food and Drug Administration (FDA) Pre-Market Approval in September 1990 and was then released through formal training certification of physicians at each new site. Procedure volume has increased dramatically since approval, with > 17,000 DCA procedures performed in 1991 and a cumulative total of > 33,000 procedures by mid-1992, at > 670 centers in the United States. Clinical application and results since approval have generally been similar to preapproval multicenter investigational results. Comparison of pre- and postapproval usage at the Medical College of Virginia shows similar baseline characteristics and indications, although recent patients show a higher proportion of "salvage" DCA for failed or suboptimal angioplasty (6% vs 14%) or DCA in combination with multidevice multiple vessel intervention (30% vs 38%). Overall results in 300 patients and 345 procedures included procedural success in 95%, clinical success in 94%, with major complications in 4.6% (including urgent bypass surgery in 3.8%, Q wave myocardial infarction in 1.7%, and hospital mortality in 0.3%). Results before and after FDA approval were similar for procedural success (94% vs 96%), clinical success rate (94% vs 94%), and major complications (5.5% vs 4.4%). There was a trend toward lower urgent surgery rate (5.4% vs 3.3%) in the more recent experience. In addition to its established efficacy for highly eccentric lesions, newer applications for which DCA is being used following FDA approval include treatment of saphenous vein grafts, thrombus-associated lesions, aorto-ostial lesions, failed or suboptimal percutaneous transluminal coronary angioplasty result, bifurcation lesions, and use as part of multivessel intervention.(ABSTRACT TRUNCATED AT 250 WORDS)