Vein Graft Stenosis Research Articles

Low Wall Shear Stress Is Associated with Saphenous Vein Graft Stenosis in Patients with Coronary Artery Bypass Grafting.

Biomechanical forces may play a key role in saphenous vein graft (SVG) disease after coronary artery bypass graft (CABG) surgery. Computed tomography angiography (CTA) of 430 post-CABG patients were evaluated and 15 patients were identified with both stenosed and healthy SVGs for paired analysis. The stenosis was virtually removed, and detailed 3D models were reconstructed to perform patient-specific computational fluid dynamic (CFD) simulations. Models were processed to compute anatomic parameters, and hemodynamic parameters such as local and vessel-averaged wall shear stress (WSS), normalized WSS (WSS*), low shear area (LSA), oscillatory shear index (OSI), and flow rate. WSS* was significantly lower in pre-diseased SVG segments compared to corresponding control segments without disease (1.22 vs. 1.73, p = 0.012) and the area under the ROC curve was 0.71. No differences were observed in vessel-averaged anatomic or hemodynamic parameters between pre-stenosed and control whole SVGs. There are currently no clinically available tools to predict SVG failure post-CABG. CFD modeling has the potential to identify high-risk CABG patients who may benefit from more aggressive medical therapy and closer surveillance. Graphical Abstract.

Influence of lipoproteins and antiplatelet agents on vein graft patency 1 year after coronary artery bypass grafting

ObjectiveIt remains unclear whether aggressive low-density lipoprotein cholesterol (LDL-C) management (<1.8 mmol/L) can slow the process of vein graft stenosis. This study aimed to explore the impact of baseline LDL-C levels on vein graft patency in patients on ticagrelor with or without aspirin 1 year after coronary artery bypass grafting (CABG). MethodsThis was a post hoc analysis of the DACAB (Different Antiplatelet Therapy Strategy After Coronary Artery Bypass Graft Surgery) trial (NCT02201771), a randomized controlled trial (ticagrelor + aspirin or ticagrelor vs aspirin) of patients undergoing CABG in China. The study subjects were stratified as LDL-low (baseline LDL-C <1.8 mmol/L, 148 patients with 430 vein grafts) versus LDL-high (baseline LDL-C ≥1.8 mmol/L, 352 patients with 1030 vein grafts). The primary outcome was the 1-year vein graft patency (Fitzgibbon grade A) assessed by coronary computed tomographic angiography or coronary angiography. ResultsBaseline/1-year LDL-C were 1.4/1.6 and 2.6/2.4 mmol/L in the LDL-low and LDL-high subgroups, respectively. Regardless of antiplatelet regimen, no significant inter-subgroup difference was observed for 1-year graft patency (LDL-low: 83.8% [359/430 grafts]; LDL-high: 82.3% [848/1030 grafts]; adjusted OR for non-patency [ORadj], 0.96; 95% confidence interval [CI], 0.62-1.50, P = .857). For both subgroups, the 1-year graft patency rates were greater with ticagrelor + aspirin versus aspirin (LDL-low: ORadj, 0.41; 95% CI, 0.17-0.97; LDL-high: ORadj, 0.38; 95% CI, 0.20-0.71; inter P = .679). ConclusionsIn general, baseline LDL-C is not associated with 1-year vein graft patency after CABG. Regardless of the baseline LDL-C levels, ticagrelor + aspirin was superior to aspirin alone in maintaining vein graft patency. The primary factor causing early vein graft disease might not be atherosclerosis but thrombosis.

Optical coherence tomography of coronary grafts

Background. Coronary artery bypass graft surgery is the most common cardiac surgery in the world. Graft failure is a complex multifactorial process that occurs in a significant part of all grafts.Aim. To identify predictors of early coronary bypass failure using optical coherence tomography.Methods. A prospective observational study included 10 patients with multivessel coronary artery disease who underwent coronary artery bypass grafting. After surgical myocardial revascularization, the patients underwent coronary angiography with optical coherence tomography (OCT) of arterial and venous grafts, including the distal anastomosis and conjugate segment of the target coronary artery. Endothelial damage; the presence of severe tortuosity, stenosis, spasm and parietal thrombi; the ratio of the diameters of the conduit and the native coronary artery was assessed.Results. A control study revealed several findings. In one case, the left internal mammary artery was occluded, which required stenting of the left anterior descending artery. In one patient, a dissection of the left internal mammary artery anastomosis was revealed, while a double lumen with the formation of a false channel was revealed on the OCT. In one case, stenosis of a saphenous vein graft on the right coronary artery was determined (53.1% by area). In three cases, a pronounced recalibration of the diameters of the saphenous vein graft and the target coronary artery with more than two times the ratio was revealed, and in one case, the diameter of the target artery was less than 2 mm.Conclusion. OCT is an effective method for visualizing morphological changes not only in coronary arteries, but also in coronary bypass grafts, which may be associated with early graft failure.

Transcriptomic profiling of experimental arterial injury reveals new mechanisms and temporal dynamics in vascular healing response

ObjectiveEndovascular interventions cause arterial injury and induce a healing response to restore vessel wall homeostasis. Complications of defective or excessive healing are common and result in increased morbidity and repeated interventions. Experimental models of intimal hyperplasia are vital for understanding the vascular healing mechanisms and resolving the clinical problems of restenosis, vein graft stenosis, and dialysis access failure. Our aim was to systematically investigate the transcriptional, histologic, and systemic reaction to vascular injury during a prolonged time. MethodsBalloon injury of the left common carotid artery was performed in male rats. Animals (n = 69) were euthanized before or after injury, either directly or after 2 hours, 20 hours, 2 days, 5 days, 2 weeks, 6 weeks, and 12 weeks. Both injured and contralateral arteries were subjected to microarray profiling, followed by bioinformatic exploration, histologic characterization of the biopsy specimens, and plasma lipid analyses. ResultsImmune activation and coagulation were key mechanisms in the early response, followed by cytokine release, tissue remodeling, and smooth muscle cell modulation several days after injury, with reacquisition of contractile features in later phases. Novel pathways related to clonal expansion, inflammatory transformation, and chondro-osteogenic differentiation were identified and immunolocalized to neointimal smooth muscle cells. Analysis of uninjured arteries revealed a systemic component of the reaction after local injury, underlined by altered endothelial signaling, changes in overall tissue bioenergy metabolism, and plasma high-density lipoprotein levels. ConclusionsWe demonstrate that vascular injury induces dynamic transcriptional landscape and metabolic changes identifiable as early, intermediate, and late response phases, reaching homeostasis after several weeks. This study provides a temporal “roadmap” of vascular healing as a publicly available resource for the research community.

Comparison of drug-eluting and bare-metal stents in patients with saphenous vein graft stenosis

BackgroundThe use of drug-eluting stents (DES) during the percutaneous coronary intervention of patients with degenerated saphenous vein graft (SVG) is uncertain. Although previous studies showed that DES might decrease the rate of re-intervention in patients with SVG stenosis, randomized controlled trials comparing bare-metal stents (BMS) and DES in SVG lesions have been inconclusive.ObjectiveThe purpose of this study was to compare the outcomes in patients undergoing SVG stent implantation treated with DES or BMS.Patients and methodsThis was a retrospective observational study that included 60 patients who underwent percutaneous coronary intervention for SVG lesions, comprising 30 patients who were treated with BMS and 30 patients who were treated with DES at National Heart Institute from March 2015 to March 2018. Three years of outcome and major adverse cardiac event (MACE) were recorded. MACE was defined as death, myocardial infarction (MI), target vessel revascularization, and stroke.ResultsAfter three years, there was no significant difference between the two groups in MACE. MACE was reported in five (16.6%) patients in the DES group vs eight (26.6%) patients in the BMS group (P>0.05). Death was reported in one (3.3%) patient in each group. MI was reported in two (6.6%) patients in the DES group vs three (10%) patients in the BMS group (P>0.05). One (3.3%) patient developed stroke in the DES group vs two (6.6%) patients in the BMS group (P>0.05). The need for repeat revascularization was reported in one (3.3%) patient in the DES group vs two (6.6%) patients in the BMS group (P>0.05). Stent thrombosis was reported in six (20%) patients in the DES group vs four (13.3%) patients in the BMS group (P>0.05)ConclusionOur results in this study showed that there was no significant difference between BMS and DES in patients undergoing percutaneous coronary intervention for SVG lesions for MACE, such as death, target vessel revascularization, and MI.

Drug Coated Balloons vs. Conventional Balloon Angioplasty for Bypass Vein Graft stenosis – A Randomized Controlled Trial

Introduction - Stenosis and restenosis are known complications of endovascular treatment of native arteries and bypass vein grafts in peripheral arterial disease (PAD). (1,2) This may lead to loss of the bypass graft, which can be a problem due to the limited availability of autologous vein material. Drug-coated balloons seem to be effective in the treatment of native artery stenosis (3). The biomechanical and anatomical properties of vein grafts differ greatly from native arteries, and less is known about the potential of drug-coated devices in this field. One randomized trial did not demonstrate benefit from use of DCBs over BA in bypass vein grafts. (4) Similar results were observed in a retrospective study comparing BA to DCB in peripheral grafts (5). The aim of this study was to evaluate the effect of drug-coated balloons in the treatment of vein graft stenoses. Design: Single-center, parallel, randomized controlled trial. Block randomized by sealed envelope 1:1. Methods - 60 patients treated for primary or recurrent stenosis in venous bypass grafts were randomized to drug-coated balloon (DCB) (n=30) or standard balloon angioplasty (BA) (n=30). Follow-up was 1 year. Primary outcome measures were target lesion revascularization (TLR) and graft occlusion. Primary assisted patency and secondary patency were also assessed. Results - 57 cases were ultimately included in the study. 3 randomized cases were excluded due to primary technical failure (graft rupture during predilatation and bail-out stenting (N=2), aborted procedure (N=1)). Six patients died during follow-up (DCB 4, BA 2) and one patient underwent major amputation (BA group). 23 patients underwent re-revascularization of the same segment (DCB 10/29, 34.5 % vs. BA 13/28, 46.4 %, p=0.333). The overall TLR-rate at one year was 34.5 % and 46.4 % in the DCB and BA groups respectively (p=0.33). 5/57 (8.8 %) grafts occluded during the follow-up, 1/29 (3.4 %) and 4/28 (14.3 %) in the DCB and BA groups respectively (p=0.36). Secondary patency was 100 % in the DCB group compared to 89.3% in the BA group (p=0.076). In subanalysis including only de novo lesions TLR was significantly lower in grafts that were treated with DCB compared to BA (15 % vs. 18.9 %, P=0.03). Conclusion - There is a trend toward benefit from DCBs in the treatment of graft stenosis; this difference is significant in previously untreated lesions. There has been hesitation towards using drug-coated balloons as a first choice in the treatment of graft stenosis. Our results suggest that this hesitation might be unfounded, especially in de novo lesions. More data is needed to accurately select which lesions will benefit from DCBs. Furthermore; histological studies on paclitaxel uptake and response in the arterialized venous wall are warranted.

Ultrasound Surveillance of Insitu Bypass Grafts - is it Worth the Effort?

Introduction: In surgical fit patients with critical limb ischaemia (CLI) a great saphenous vein bypass is the recommended treatment for long occlusions of the infra-popliteal segment ADDIN EN.CITE ADDIN EN.CITE.DATA 1. Development of vein graft stenosis and bypass failure is observed in as much as 40% within the first 12 months2 and duplex ultrasound (DUS) surveillance has been broadly implemented with the aim to increase patency. ADDIN EN.CITE ADDIN EN.CITE.DATA Nevertheless, the evidence supporting this many DUS examinations are conflicting. ADDIN EN.CITE ADDIN EN.CITE.DATA 2, 3 Most cohorts in the literature are heterogeneous and report on a variety of autogenous vein conduits (insitu vein, reversed vein, arm vein and spliced vein) and indications (claudication or CLI) making generalizability difficult.3 The aim of this study was to describe patency of insitu saphenous vein bypass (ISSVB) in critical limb ischaemia and to analyse the added value of systematic DUS surveillance of in situ saphenous vein bypass. Methods: Single centre study including all patients undergoing ISSVB surgery due to CLI between 2011 and 2015. Postoperative graft surveillance program were offered to all patients, including clinical examination, ABI and DUS at 6 weeks, 3 and 12 months. The study was based on prospective entered data from the Danish Vascular Registry and primary endpoints were re-intervention rate and patency. To avoid idealization of the survival plots we decided to include occlusion, amputation and death as endpoints in both plots and use reintervention as the only variable in the Kaplan Meyer estimates. Results: In total 392 consecutive and treatment naive CLI-patients were revascularized with ISSVB and included in the study. Of those, 326 patients had minimum one follow up visit resulting in 1267 DUS examinations. During the study period, 95 (24%) patients received 143 reinterventions to avoid graft failure, 76 patients (80%) with percutaneous transluminal angioplasty (PTA) and 19 patients (20%) with surgical revision. Only 18 patients (20 reinterventions) were revised solely based on DUS findings (significant stenosis) without simultaneous ischemic symptoms or significant (>15%) decrease in ankle brachial index. Hence, to find one asymptomatic graft stenosis requiring reintervention one need to scan 65 patients (1267:20=65). Occlusion- and amputation-free survival (OAS) after 1, 2 and 3 years was 59.7% (95%-CI: 54.6-64.5), 45.3% (39.6-50.9) and 32.3% (26.4-38.4), respectively (figure 1). Reintervention-, occlusion-, and amputation-free survival (ROAS) after 1, 2 and 3 years was 47.6% (42.5-52.6), 33.5% (28.1-38.9) and 21.1% (16.0-26.7). Conclusion: The KM-plots showed a significant difference between ROAS and OAS until 2½ years postoperatively, indicating a modest (approximately 10%) effect of reintervention on graft stenosis. In this study, every fourth of ISSVB patients received a graft-preserving intervention but very few were driven by routine DUS as most graft lesions were recognised on symptoms and clinical findings. This finding suggests that development of more individualised surveillance programs differentiating between high and low risk patients may be more cost effective. Disclosure: Nothing to disclose

Efficacy of Balloon Angioplasty for Infrainguinal Vein Graft Stenosis

Vein graft stenosis is a critical complication of lower-limb bypass surgery. For vein graft stenosis, balloon angioplasty has been performed instead of surgical revision in recent years. We therefore investigated the effectiveness of the balloon angioplasty for vein graft stenosis. We conducted a retrospective analysis of prospectively collected data for 115 vein graft stenoses performed via balloon angioplasty from August 2011 to January 2018. The rate of freedom from reintervention after balloon angioplasty was 54.3%, 44.4%, and 38.0% at 1, 2, and 3years, respectively. The rate of freedom from graft occlusion after balloon angioplasty was 79.9%, 71.9%, and 61.3% at 1, 2, and 3years, respectively. Predictors of freedom from graft occlusion after balloon angioplasty by a multivariate analysis were a single treated lesion (hazard ratio [HR]: 0.38; 95% confidence interval [CI]: 0.17-0.85; P=0.0189), balloon angioplasty within 90days after bypass surgery (HR: 3.59; 95% CI: 1.56-8.07; P=0.0033), and using a cutting balloon (HR: 0.42; 95% CI: 0.17-0.97; P=0.0426). The freedom from graft occlusion rate after balloon angioplasty remained relatively high. Furthermore, better results can be expected in single treated lesions and cases of balloon angioplasty occurring 90days after bypass surgery or in which a cutting balloon was used. Balloon angioplasty for lower-limb bypass graft stenosis was shown to be a useful treatment.

Inhibitory effect of irisin on vasular smooth muscle cell inflammation and proliferation by regulating autophagy through adenosine monophosphate-actived protein kinase/mammalian target of rapamycin pathway

Objective To explore the underlining mechanisms of irisin inhibiting inflammation and proliferation of vascular smooth muscle cells (VSMCs). Methods The cultured primary rat aortic VSMCs were pre-incubated with irisin and then treated with platelet derived growth factor-BB (PDGF-BB). Enzyme linked immunosorbent assay (ELISA) and methyl thiazol tetrazolium (MTT) assay were used to measure the VSMCs inflammation and proliferation, respectively. The protein expression and phosphorylation of adenosine monophosphate-actived protein kinase (AMPK)/mammalian target of rapamycin (mTOR) signaling pathway related molecule AMPK/p-AMPK (Thr172), acetyl-CoA carboxylase (ACC)/phosphorylated (p)-ACC (Thr308), mTOR/p-mTOR (Ser2448), ribosomal protein S6 kinase (p70SK6)/p-70SK6 (Thr389), and autophay related molecule microtubule-associated protein 1 light chain 3 (LC3) Ⅰ, LC3Ⅱ and nucleoporin p62 (P62) were detected by Western blotting. Results After treatment with PDGF-BB, VSMCs proliferation dramatically increased, and the inflammatory cytokines IL-1β (37.9±8.5 vs. 10.8±2.9, t=18.620, P<0.01), IL-6 (57.4±14.1 vs. 32.4±8.7, t=6.250, P<0.01), MCP-1 (158.3±39.1 vs. 57.2±12.5, t=14.280, P<0.01), ICAM-1 (371.8±77.3 vs. 160.4±39.8, t=10.850, P<0.01), tumor necrosis factor-α (TNF-α) (16.3±3.8 vs. 7.8±2.4, t=7.390, P<0.01) in the cell supernatant were significantly up-regulated. The protein expression levels of AMPK (0.39±0.11 vs. 0.83±0.18, t=14.250, P<0.01), p-AMPK (0.25±0.03 vs. 0.49±0.12, t=12.370, P<0.01), ACC (0.54±0.16 vs. 1.07±0.24, t=10.670, P<0.01), p-ACC (0.38±0.07 vs. 0.97±0.30, t=18.130, P<0.01), LC3Ⅰ (0.67±0.21 vs. 0.67±0.21, t=5.780, P<0.01) and LC3Ⅱ (0.42±0.13 vs. 0.93±0.38, t=6.820, P<0.01) were down-regulated, mTOR (2.57±0.53 vs. 1.23±0.25, t=21.350, P<0.01), and p-mTOR (1.35±0.0.37 vs. 0.57±0.12, t=8.870, P<0.01), p70SK6 (1.85±0.39 vs. 0.81±0.19, t=7.170, P<0.01), p-70SK6 (0.69±0.22 vs. 0.38±0.11, t=9.260, P<0.01) and P62 (1.24±0.38 vs. 0.58±0.14, t=5.270, P<0.01) were up-regulated. However, pre-incubation with irisin and then stimulation with PDGF-BB could significantly decrease VSMCs proliferation [(122.14±9.42)%, t=4.970, P<0.01], and significantly down-regulate the inflammatory cytokines IL-1β (17.38±4.10, t=6.740, P<0.01), IL-6 (34.9±8.9, t=2.760, P<0.05), MCP-1 (47.28±9.20, t=16.270, P<0.01), ICAM-1 (169.2±55.8, t=7.780, P<0.01) and TNF-α (6.9±2.0, t=8.180, P<0.01) in the cell supernatant. The protein expression levels of AMPK (0.72±0.26, t=2.670, P<0.05), p-AMPK (0.46±0.13, t=3.280, P<0.05), ACC (0.95±0.28, t=5.870, P<0.01), p-ACC (0.78±0.25, t=3.140, P<0.01), LC3Ⅰ (1.34±0.35, t=1.960, P<0.05) and LC3Ⅱ (1.03±0.19, t=7.260, P<0.01) were up-regulated, and mTOR (1.16±0.33, t=6.910, P<0.01), p-mTOR (0.66±0.18, t=6.830, P<0.01), p70SK6 (1.12±0.34, t=2.360, P<0.05), p-70SK6 (0.37±0.12, t=3.120, P<0.01) and P62 (0.68±0.18, t=3.360, P<0.05) were down-regulated. Conclusion Irisin could inhibit the inflammation and proliferation of VSMCs possibly by up-regulating autophagy through activation of the AMPK/mTOR signaling pathway. Key words: Irisin; Adenosine monophosphate-actived protein kinase/mammalian target of rapamycin signaling pathway; Autophagy; Vascualar smooth muscle cell proliferation; Vein graft stenosis

Investigation of relationship between mean platelet volume and saphenous vein graft restenosis after coronary artery bypass grafting

Objective To investigate the relationship between mean platelet volume(MPV)and saphenous vein graft restenosis in patients receiving coronary artery bypass grafting(CABG), and to analyze the clinical significance of MPV in the prediction of restenosis after CABG. Methods A total of 354 patients admitted into Tianjin chest hospital from September 2009 to September 2014 with suspected myocardial ischemic events 3 to 5 years after CABG treatment was enrolled for a retrospective analysis.According to the coronary angiography(CAG)results, patients were divided into the vein bridge vascular lesion group(saphenous vein graft diseases, SVGD)(n=233)and the venous bridge vascular patency group(saphenous vein graft, SVG)(n=121). Paired t test was used to analyze the relationship between different factors and the bridge vascular patency.The binary logistic regression was used to analyze the effects of MPV and other factors on bridge vascular patency.Venous bridge stenosis >50% was considered to be clinically significant and to damage myocardial blood supply. Results The MPV was higher in the SVGD group than the SVG group[(10.2±1.5)fl vs.(9.6±1.5)fl, P<0.01]. The logistic regression analysis showed that MPV(OR=1.268, 95%CI: 1.053-1.570, P=0.014), age(OR=1.007, 95%CI: 1.038-1.117, P=0.000), gender(OR=0.452, 95%CI: 0.250-0.816, P=0.008), diabetes mellitus(OR=2.319, 95%CI: 1.221-4.405, P=0.010)were the independent risk factors for venous bridge stenosis in the two groups, gender(OR=0.495, 95%CI: 0.251-0.976, P=0.042), diabetes mellitus(OR=2.237, 95%CI: 1.105-4.527, P=0.025), MPV(OR=1.334, 95%CI: 1.050-1.694, P=0.018), fibrinogen(OR=1.654, 95%CI: 1.020-2.682, P=0.041)were the independent risk factors for venous bridge stenosis in non-elderly patients, and age(OR=1.178, 95%CI: 1.116-1.244, P=1.178)was an independent risk factor for vein graft stenosis in elderly patients.The restenosis rate was higher in patients with MPV ≥ 12 fl(92.6% or 25/27)than in the patients with MPV < 12 fl(63.6% or 208/327). The receiver operating characteristics(ROC)curve showed that the areas under the curve of MPV, age, gender, diabetes, fibrinogen were 0.610, 0.657, 0.394, 0.626, 0.654, respectively, and the area under the curve of joint diagnosis was 0.796, showing that joint prediction value was higher than any single prediction value(P<0.01). Conclusions MPV level is an independent risk factor for vein graft stenosis, and has higher predictive value in combination with age, gender, diabetes and fibrinogen. Key words: Platelets; Cardiovascular disease; Coronary artery bypass, off-pump; Saphenous vein

Closure of LIMA and a Saphenous vein graft within a short period of six months post CABG in presence of patent RIMA

Appropriate revascularization decision and proper conduit selection are the most important factors to maintain adequate coronary flow and the function of the coronary bypass grafts after coronary artery bypass graft (CABG) surgery. Left internal mammary artery (LIMA) is considered to be the gold standard choice graft for bypass surgery, as its patency rates are around 90-95%, ten to fifteen years after CABG. Here, we report a case of a 58-year-old man who underwent CABG six months ago and presented for evaluation and management of worsening angina. Cardiac catheterization revealed total occlusion LIMA and severe stenosis of saphenous vein graft (SVG) in the presence of patent right internal mammary artery (RIMA).

Rotational Atherectomy Before Stenting in the Body of a Saphenous Vein Graft

Management of stenosis of saphenous vein grafts in Coronary artery bypass graft (CABG) patients remains challenging despite the advance in interventional cardiology techniques. Rotational atherectomy is an adjunctive technique used in certain anatomical conditions in native coronary arteries; its use in saphenous vein graft is still contra-indicated by the manufacturer, and has only been reported in few cases in the literature. We report a case of a calcified, non-dilatable, distal saphenous vein graft to Circumflex lesion in a heart failure patient presenting with Non STEMI. The lesion was just proximal to the anastomosis and could not be crossed. Because of high surgical risk, and against manufacturer guidelines, rotational atherectomy of the lesion was performed and was successful with a very good angiographic result. Rotational atherectomy to facilitate percutaneous interventions in saphenous vein graft lesions is feasible, and could be attempted in experienced centers provided the absence of luminal thrombus or dissection.

The Predictive Effects of Clinical Hematological Changes on Saphenous Graft Patency after Coronary Artery Surgery.

ObjectivesTo investigate the association between clinical hematologic parameters and saphenous vein graft failure after on-pump coronary artery bypass surgery.MethodsA total of 1950 consecutive patients underwent isolated on-pump coronary artery surgery between November 2010 and February 2013. Of these, 284 patients met our inclusion criteria; their preoperative clinical hematological parameters were retrospectively obtained for this cohort study. And of them, 109 patients underwent conventional coronary angiography after graft failure was revealed by coronary computed tomography angiography. The primary endpoint was to catch at least one saphenous vein graft stenosis or occlusion following the coronary angiogram. We then analyzed risk factors for graft failure. In sequential or T grafts, each segment was analyzed as a separate graft.ResultsIn logistic regression analysis, older age, platelet distribution width, and diabetes mellitus were identified as independent predictors of saphenous vein graft failure (P<0.). In contrast, preserved ejection fraction value favored graft patency (P<0.001).ConclusionIncreased platelet distribution width is easily measurable and can be used as a simple and valuable marker in the prediction of saphenous vein graft failure.

Drug-Eluting Stents Versus Bare-Metal Stents in Saphenous Vein Graft Intervention.

Background Percutaneous coronary intervention with drug-eluting stents (DES) has been increasingly used for revascularization of saphenous vein graft stenosis without strong clinical evidence favoring their use. Randomized controlled trials comparing DES versus bare-metal stents (BMS) in saphenous vein graft-percutaneous coronary intervention have been inconclusive. Methods and Results We performed a comprehensive literature search through May 15, 2018, for all eligible studies comparing DES versus BMS in patients with saphenous vein graft stenosis in PubMed, EMBASE, SCOPUS, Google Scholar, and ClinicalTrials.gov. Clinical outcomes included all-cause mortality, cardiovascular mortality, major adverse cardiovascular events, myocardial infarction, stent thrombosis, and target vessel revascularization. Six randomized controlled trials were eligible and included 1582 patients, of whom 797 received DES and 785 received BMS. The follow-up period ranged from 18 months to 60 months. There was no statistically significant difference between DES and BMS for all-cause mortality (risk ratio [RR],1.11; 95% CI, 0.0.77-1.62; P=0.57), cardiovascular mortality (RR, 1.00; 95% CI, 0.64-1.57; P=0.99), major adverse cardiovascular events (RR, 0.83; 95% CI, 0.63-1.10; P=20), target vessel revascularization (RR, 0.73; 95% CI, 0.48-1.11; P=0.14), myocardial infarction (RR, 0.74; 95% CI, 0.48-1.16; P=0.19), or stent thrombosis (RR, 1.06; 95% CI, 0.42-2.65; P=0.90). Conclusions In patients undergoing percutaneous coronary intervention for saphenous vein graft lesions, our results showed that there was no significant difference between DES and BMS for mortality, major adverse cardiovascular events, target vessel revascularization, myocardial infarction, or stent thrombosis.

Drug-Coated versus Plain Balloon Angioplasty in Bypass Vein Grafts (the DRECOREST I-Study)

Stenosis is a known complication in bypass vein grafts for peripheral arterial disease. The aim of this study was to evaluate the effect of drug-coated balloons (DCBs) in the treatment of vein graft stenoses. DCBs may prevent restenosis in arterial lesions. One small prospective and larger retrospective and registry studies have failed to show benefit from DCBs in vein grafts. Prospective data are scarce. Sixty patients treated for primary or recurrent stenosis in venous bypass grafts were randomized to DCB (n=30) or standard balloon angioplasty (BA) (n=30). Follow-up was 1year. The primary outcome measure was target lesion revascularization (TLR). Secondary outcome measures were assisted primary patency and secondary patency and graft occlusion. Fifty-seven patients were analyzed. Three patients were excluded due to primary technical failure (2 DCB, 1 BA). Overall TLR rate was 34.5% and 46.4% in the DCB and BA groups, respectively (P=0.33). Five (8.8%) grafts occluded during follow-up (1 DCB, 4 BA). Assisted primary patency was 93.1% (DCB) versus 85.7% (BA) (P=0.362) and secondary patency was 100% (DCB) versus 89.3% (BA) (P=0.076). Subgroup analysis showed a significant benefit from DCB in the treatment of primary stenosis (TLR rate 15.0% vs. 18.9%, P=0.03). There was no significant benefit from DCBs for treatment of vein graft stenosis compared to BA, although a trend in favor of DCBs could be seen. ClinicalTrials.govNCT03023098.

Intensive versus moderate statin therapy and early graft occlusion after coronary bypass surgery: The Aggressive Cholesterol Therapy to Inhibit Vein Graft Events randomized clinical trial

ObjectiveStatins prevent saphenous vein graft (SVG) disease and improve outcomes after coronary artery bypass graft surgery. However, the optimal postoperative statin dose remains unclear. The Aggressive Cholesterol Therapy to Inhibit Vein Graft Events trial was undertaken to evaluate whether early postoperative high-dose statin therapy reduces SVG occlusion compared with conventional moderate-dose therapy. MethodsIn this pilot, multicenter, double-blind randomized trial, 173 patients who had coronary artery bypass graft surgery with SVG were randomized to receive 10 mg or 80 mg atorvastatin daily for 1 year. The primary outcome was SVG occlusion at 1 year. Secondary outcomes were SVG stenosis and major adverse cardiovascular events. ResultsDuring trial enrollment, patients randomized to 80 mg atorvastatin achieved significantly lower low-density lipoprotein cholesterol levels (P < .00001). One-year graft assessment was performed in 145 patients (83.8%). The primary outcome, SVG occlusion at 1 year, did not significantly differ between the 2 groups (12.9% vs 11.4% for 10 mg atorvastatin vs 80 mg atorvastatin; P = .85). The incidence of vein graft stenosis also did not significantly differ between the groups (P = .54). However, there was a trend toward fewer patients developing vein graft disease (either occlusion or stenosis) in the 80 mg atorvastatin group (29.2% vs 19.2%, 10 mg atorvastatin vs 80 mg atorvastatin; P = .18). Freedom from major adverse cardiovascular events at 1 year was similar between the groups (P = .27). ConclusionsCompared with 10 mg atorvastatin, 80 mg atorvastatin did not significantly reduce vein graft occlusion 1 year after coronary artery bypass graft surgery in this pilot trial.

Abstract 692: Development of the Gene Therapy With CRE Decoy ODN to Prevent Vascular Intimal Hyperplasia

Background: Intimal hyperplasia (IH) is the main cause of vein graft stenosis or failure after bypass surgery. However, in the previous study, no therapeutic targets for the treatment of IH have been identified. Our recent research have been reported that the inhibition of Cyclic adenosine monophosphate response-element (CRE) binding protein (CREB) activation is a key role for vein graft IH. Objective: In consideration of future clinical application, we focused on decoy oligodeoxynucleotide (ODN) transfection as gene therapy strategy for suppressing IH. The goal of the present study is to identify whether the CRE decoy ODN had the therapeutic efficacy for suppressing IH. Methods: We developed phosphorothioate CRE decoy ODN and checked binding ability to a CRE sequence using CREB transcription assay . We chose a decoy ODN having high first-binding ability and transfected it to vascular smooth muscle cell(VSMC) in vitro. Proliferation was assessed using MTS assay and migration was assessed using a modified Boyden-chamber assay. We examined CRE activity using Luciferase reporter gene assay. We checked expression of mRNAs using qRT-PCR. In wire-injury mouse model(C57BL6,n=6), CRE decoy ODN was transfected to injured vessel wall using ultrasound-sonoporation method in vivo. Results: CREB transcription factor assay showed CRE decoy had about 80 folds binding ability of control decoy in IC50 value (vs.control,n=5). Transfer of CRE decoy ODN resulted in significantly downregulated CRE activity(vs.control,P&lt;.01,n=12) and inhibited VSMC proliferation (vs.control,P&lt;.01,n=12) and migration (vs.control,P&lt;.01,n=5). In a wire-injury mouse model, histopathological analysis revealed that transfer of the CRE decoy ODN significantly repressed IH whereas intensive IH was observed in the control group. In this vessel tissue, Levels of mRNA CCNA2 and Bcl2 were significantly lower in CRE decoy group than in control group(n=6,P&lt;.01,respectively). CRE-activated gene expression was strongly repressed. Conclusions: The present result suggested that CRE decoy ODN inhibiting CREB function provide an effective therapeutic approach to suppressing IH.

Impact of ticagrelor versus aspirin on graft patency after CABG: Rationale and design of the TARGET (ticagrelor antiplatelet therapy to reduce graft events and thrombosis) randomized controlled trial (NCT02053909)

RationaleSaphenous vein graft disease remains a major limitation of coronary artery bypass graft surgery (CABG). Up to 20% of vein grafts will occlude within the first year after CABG despite standard aspirin antiplatelet therapy. However, more potent postoperative platelet inhibition with ticagrelor may improve graft patency. The goal of this study will be to evaluate the efficacy of ticagrelor, as compared to aspirin, for the prevention of saphenous vein graft occlusion following CABG. Study designThe Ticagrelor Antiplatelet Therapy to Reduce Graft Events and Thrombosis (TARGET) study is a multi-center double-blind randomized controlled trial enrolling patients who have undergone multi-vessel CABG with at least one saphenous vein graft. Patients are being randomized to receive either aspirin 81 mg twice per day or ticagrelor 90 mg twice per day for 2 years starting within 7 days after surgery. The projected enrollment is 150 patients in each arm (300 total patients). Patients will undergo computed tomography (CT) coronary angiography at 1 and 2 years after surgery to assess the incidence of vein graft occlusion and stenosis. ConclusionTo our knowledge, this trial is the first prospective study to evaluate the impact of early postoperative ticagrelor on 1- and 2-year graft patency after CABG. Furthermore, it is also the first trial to use a novel antiplatelet agent as a standalone, without aspirin, after CABG. Should ticagrelor reduce the incidence of postoperative graft occlusion, the results of this study will redefine modern antiplatelet management following coronary bypass surgery (ClinicalTrials.govNCT02053909).

Ultrasound-guided percutaneous endovascular treatment of arteriovenous fistula/graft.

Ultrasound-guided percutaneous endovascular treatment of arteriovenous fistula (AVF) or graft failure is an alternative to radiologically-guided angioplastic methods. Its main advantages are that it can be used with open or percutaneous access, using no contrast media and no radiation. The aim of this study was to analyze the results of ultrasound-guided endovascular treatment of arteriovenous access failure. Preoperative ultrasound was used to determine the degree of stenosis and the size of balloon used in angioplasty. Angioplasty was performed as open procedure or by using a 4-6 French percutaneous sheath. Indications for angioplasty were significant stenosis of native vein or polytetrafluoroethylene (PTFE) graft with or without AVF thrombosis. Stenosis was considered significant if it narrowed the lumen of AVF for more than 50% and changed the shape of the flow curve. Balloon inflation was controlled by ultrasound. Procedural success was assessed with repeated postprocedural ultrasound. In the period from August 2012 until August 2016, 228 ultrasound-guided open or percutaneous transluminal angioplasties (PTA) were performed (61% men, mean age 66.6±12.0 years), success rate was 93%. In 19 (8%) cases, ultrasound-guided PTA was used in conjunction with surgical reconstruction of arteriovenous fistula/graft and in 27 (12%) cases with thromboendarterectomy. Main complications were recoil, phlebitic vein rupture, and guidewire false route in thrombotic vessels. The main cause of access failure was perianastomotic stenosis (25%). 46% of patients required repeated PTA after the first one (after a mean time of 20.8±22.8 weeks, mean number of repeated PTA 2.1±1.7). Repeated PTA was done intentionally as stepped dilatation or because of rethrombosis/restenosis. Ultrasound-guided stent placement was done in 8% of PTA. Ultrasound-guided endovascular treatment of arteriovenous fistula or graft is a feasible and safe method of reestablishing or maintaining a functional vascular access. .

Intensive versus moderate atorvastatin therapy and one-year graft patency after CABG: Rationale and design of the ACTIVE (Aggressive Cholesterol Therapy to Inhibit Vein Graft Events) randomized controlled trial (NCT01528709)

RationaleSaphenous vein graft disease remains a major limitation of coronary artery bypass graft surgery (CABG). Statin therapy inhibits the development of vein graft disease and improves outcomes after CABG. However, it is unclear whether treatment with high-dose statins will further slow the process of vein graft disease and improve graft patency, as compared to conventional moderate doses. Therefore, the goal of this study will be to evaluate the efficacy of high-dose statin therapy versus moderate-dose statin therapy for the prevention of saphenous vein graft occlusion following CABG. Study designThe Aggressive Cholesterol Therapy to Inhibit Vein Graft Events (ACTIVE) trial is a multi-center double-blind randomized controlled trial enrolling patients who have undergone multi-vessel CABG with at least one saphenous vein graft. Patients will be randomized to receive either atorvastatin 80mg daily or atorvastatin 10mg daily for one year starting within 5days after surgery. The target enrollment is 100 patients in each arm (200 patients total). Lipid levels will be assessed every 3months. After one year, patients will undergo computed tomography (CT) coronary angiography to assess the incidence of vein graft occlusion and stenosis. ConclusionThis trial is the first prospective study to evaluate the impact of early postoperative high-dose statin therapy on graft patency after CABG. Should high-dose statin therapy reduce the incidence of postoperative graft occlusion, the results will add to the growing evidence supporting the role of high-intensity statins for modern lipid management after coronary surgical revascularization (ClinicalTrials.govNCT01528709).