5-Year Follow-Up of Polytetrafluoroethylene-Covered Stents Compared With Bare-Metal Stents in Aortocoronary Saphenous Vein Grafts

Clinical Outcomes of Comparison Between Type III Coronary Artery Perforation (CAP) and non-CAP Acute Coronary Syndrome Patients During 3-Year Follow-up

Coronary artery perforation (CAP) is a potentially fatal complication of percutaneous coronary intervention (PCI) in acute coronary syndrome (ACS). This study aimed to investigate in-hospital, 1-year, and 3-year clinical outcomes of type III CAP during PCI in patients with ACS. The study retrospectively evaluated 118 patients with CAP and 43,226 case-control patients. Clinical, angiographic, and procedural characteristics, management, and outcomes were analyzed retrospectively at 1-year and 3-year follow-ups. The mean age of the patients was 66.5 ± 11.9 years (61.8% males). There was no significant difference in hospital mortality between the type III CAP and non-CAP groups. The all-cause mortality was 33.3% in the CAP group vs 1.8% in the non-CAP group at 1 year, and 28.3% in CAP group vs 6.9% in non-CAP group at 3 years (p = .001 for both comparisons). The procedural, clinical, and 1 and 3-year outcomes of type III CAP showed a relatively high risk of myocardial infarction, coronary artery bypass graft, cerebrovascular event, stent thrombosis, and major bleeding at the 1 and 3-year follow-ups. In addition, non-CAP ACS patients had better survival (log-rank: p < .001, 34.29 months 95% Confidence Interval [33.58-35.00]) than type III CAP ACS patients (29.53 months 95% Confidence Interval [27.28-31.78]) at the 3-year follow-up visit.

Saphenous Vein Graft Intervention

Even though saphenous vein grafts (SVGs) are the most commonly used surgical conduits, their long-term patency is limited by accelerated atherosclerosis often resulting in acute coronary syndrome or asymptomatic occlusion. SVG intervention is associated with 2 significant challenges: a significant risk of distal embolization with resultant periprocedural myocardial infarction in the short-term and restenosis in the long-term. Several individual trials have compared bare metal stents with drug-eluting stents for SVG intervention. This review article discusses the pathophysiology of SVG lesions, indications for SVG intervention, and the challenges encountered, and also technical considerations for SVG intervention and the supporting evidence.

Coronary Artery Perforations: Glasgow Natural History Study of Covered Stent Coronary Interventions (GNOCCI) Study

Background The objective of the GNOCCI (Glasgow Natural History Study of Covered Stent Coronary Interventions) Study was to report the incidence and outcomes of coronary artery perforations over an 18-year period at a single, high-volume percutaneous coronary intervention center. We considered both the temporal trends and long-term outcomes of covered stent deployment. Methods and Results We evaluated procedural and long-term clinical outcomes following coronary perforation in a cohort of 43,343 consecutive percutaneous coronary intervention procedures. Procedural major adverse cardiac events were defined as a composite of death, myocardial infarction, stroke, target vessel revascularization, or cardiac surgery within 24 hours. A total of 161 (0.37%) procedures were complicated by coronary perforation of which 57 (35%) were Ellis grade III. Incidence increased with time over the study period (r=0.73; P<0.001). Perforation severity was linearly associated with procedural mortality (median 2.9-year follow-up): Ellis I (0%), Ellis II (1.7%), Ellis III/IIIB (21%), P<0.001. Procedural major adverse cardiac events occurred in 47% of patients with Ellis III/IIIB versus 13.5% of those with Ellis I/II perforations (odds ratio, 5.8; 95% CI, 2.7-12.5; P<0.001). Covered stents were associated with an increased risk of stent thrombosis at 2.9-year follow-up (Academic Research Consortium definite or probable; 9.1% versus 0.9%; risk ratio, 10.5; 95% CI, 1.1-97; P=0.04). Conclusions The incidence of coronary perforation increased between 2001 and 2019. Severe perforation was associated with higher procedural major adverse cardiac events and was an independent predictor of long-term mortality. Although covered stents are a potentially lifesaving treatment, the generation of devices used during the study period was limited by their efficacy and high risk of stent thrombosis. Registration Information Clinicaltrials.gov. Identifier: NCT03862352.

Contemporary coronary artery bypass graft surgery and subsequent percutaneous revascularization

Patients who have undergone coronary artery bypass graft (CABG) surgery are susceptible to bypass graft failure and progression of native coronary artery disease. Although the saphenous vein graft (SVG) was traditionally the most-used conduit, arterial grafts (including the left and right internal thoracic arteries and the radial artery) have improved patency rates. However, the need for secondary revascularization remains common, and percutaneous coronary intervention (PCI) has become the most common modality of secondary revascularization after CABG surgery. Procedural characteristics and clinical outcomes differ considerably from those associated with PCI in patients without previous CABG surgery, owing to altered coronary anatomy and differences in conduit pathophysiology. In particular, SVG PCI carries an increased risk of complications, and operators are shifting their focus towards embolic protection strategies and complex native-vessel interventions, increasingly using SVGs as conduits to facilitate native-vessel PCI rather than pursuing SVG PCI. In this Review, we discuss the differences in conduit pathophysiology, changes in CABG surgery techniques, and the latest evidence in terms of PCI in patients with previous CABG surgery, with a particular emphasis on safety and long-term efficacy. We explore the subject of contemporary CABG surgery and subsequent percutaneous revascularization in this complex patient population.

Clinical Outcomes following Large Vessel Coronary Artery Perforation Treated with Covered Stent Implantation: Comparison between Polytetrafluoroethylene- and Polyurethane-Covered Stents (CRACK-II Registry)

Data on the clinical outcomes comparing synthetic fluorocarbon polymer polytetrafluoroethylene- (PTFE, GraftMaster) and polyurethane- (Papyrus) covered stents (CSs) to seal coronary artery perforations (CAPs) are limited. We aimed to evaluate 30-day and 1-year clinical outcomes after PCI complicated by CAP and treated with CS. We assessed 106 consecutive patients with successful CAP sealing (122 CSs): GraftMaster (51 patients, 57 CSs) or Papyrus CS (55 patients, 65 CSs). The primary endpoint was the occurrence of major adverse cardiac events (MACE), defined as the composite of cardiac death, target lesion revascularisation (TLR), and myocardial infarction (MI). The mean age of subjects was 69 ± 9.6 years (53.8% males). No significant differences were identified between the GraftMaster and Papyrus groups at the 30-day follow-up for MACE, cardiac death, MI and stent thrombosis (ST), while significantly lower rate of TLR and TVR (p = 0.02) were confirmed in the Papyrus group. At one year, differences remained similar between stents for MACE, a trend towards a lower rate of TLR (p = 0.07), MI (p = 0.08), and ST (p = 0.08), and higher for cardiac death (p = 0.07) was observed in the Papyrus group. This real-life registry of CAP illustrated that the use of Papyrus CS is associated with lower rates of TLR and TVR at 30-day follow-up in comparison to the GraftMaster CSs and no significant differences between both assessed CS at one year of follow-up.

Advances in the Post-coronary Artery Bypass Graft Management of Occlusive Coronary Artery Disease

Revascularisation of chronic total occlusion (CTO) represents one of the most challenging aspects of percutaneous coronary intervention, but advances in equipment and an understanding of CTO revascularisation techniques have resulted in considerable improvements in success rates. In patients with prior coronary artery bypass grafting (CABG) surgery, additional challenges are encountered. This article specifically explores these challenges, as well as antegrade methods of CTO crossing. Techniques, equipment that can be used and reference texts are highlighted with the aim of providing potential CTO operators adequate information to tackle additional complexities likely to be encountered in this cohort of patients. This review forms part of a wider series where additional aspects of patients with prior CABG should be factored into decisions and methods of revascularisation.

Long-term outcomes of percutaneous coronary interventions within coronary artery bypass grafts

INTRODUCTION

The long-term outcomes of percutaneous coronary interventions (PCIs) within coronary artery bypasses are still poor as compared to those within native coronary arteries. Thus, we aimed to assess predictors of long-term clinical outcomes after PCIs of coronary bypasses.

MATERIAL AND METHODS

We enrolled 194 patients after PCIs of coronary artery bypasses at the mean age of 69.5 ±8.3 years (73.2% male). The primary study endpoint was a combination of target-vessel revascularization (TVR), target-lesion revascularization (TLR), myocardial infarction (MI), stroke, coronary artery bypass grafting (CABG) and death. The mean follow-up was 964 ±799.1 days and was completed among 156 patients. Multivariate analysis was used to assess determinants of study endpoints during follow-up. Moreover, we compared survival curves according to the type of PCI and presence of anti-embolic protection.

RESULTS

The primary endpoint of the study occurred in 59.7% of patients after the mean time of 669.6 ±598.7 days. The TVR occurred in 37.9% of individuals, TLR in 24.2%, MI in 26.3%, stroke in 4.2%, CABG in 2.1% and death in 30.5% of patients. In Cox multivariate analysis, PCI of two or more bypasses (p < 0.01), post-dilatation (p < 0.05) and no-reflow (p < 0.05) were the independent determinants of the primary study endpoint. No significant impact of anti-embolic protection devices on long-term outcomes was observed.

CONCLUSIONS

Percutaneous coronary interventions of two or more bypasses, post-dilatation and no-reflow are predictors of worse outcome in patients undergoing PCI within coronary artery bypass grafts.

Thrombogenic and Inflammatory Reactions to Biomaterials in Medical Devices

Blood-contacting medical devices of different biomaterials are often used to treat various cardiovascular diseases. Thrombus formation is a common cause of failure of cardiovascular devices. Currently, there are no clinically available biomaterials that can totally inhibit thrombosis under the more challenging environments (e.g., low flow in the venous system). Although some biomaterials reduce protein adsorption or cell adhesion, the issue of biomaterial associated with thrombosis and inflammation still exists. To better understand how to develop more thrombosis-resistant medical devices, it is essential to understand the biology and mechano-transduction of thrombus nucleation and progression. In this review, we will compare the mechanisms of thrombus development and progression in the arterial and venous systems. We will address various aspects of thrombosis, starting with biology of thrombosis, mathematical modeling to integrate the mechanism of thrombosis, and thrombus formation on medical devices. Prevention of these problems requires a multifaceted approach that involves more effective and safer thrombolytic agents but more importantly the development of novel thrombosis-resistant biomaterials mimicking the biological characteristics of the endothelium and extracellular matrix tissues that also ameliorate the development and the progression of chronic inflammation as part of the processes associated with the detrimental generation of late thrombosis and neo-atherosclerosis. Until such developments occur, engineers and clinicians must work together to develop devices that require minimal anticoagulants and thrombolytics to mitigate thrombosis and inflammation without causing serious bleeding side effects.

Utilization and outcomes of polytetrafluoroethylene covered stents in patients with coronary artery perforation and coronary artery aneurysm: Single center 15-year experience

OBJECTIVES

Determine the outcomes of polytetrafluoroethylene (PTFE) covered stents for coronary artery perforation (CAP) and coronary artery aneurysm (CAA).

BACKGROUND

PTFE covered stents have been used for treatment of potentially life-threatening CAP and CAA. The short and long-term outcomes of the PTFE covered stent for CAP and CAA have not been well studied.

METHODS

We performed a retrospective study of PTFE covered stents that were placed in the patients from 2003 to 2017. Short term outcomes included in-hospital mortality, pericardial effusion, cardiac tamponade, and length of stay. Long-term outcomes included target lesion revascularization (TLR), in-stent restenosis (ISR), and long-term mortality.

RESULTS

Fifty-three PTFE covered stents were placed in 32 patients of which there were 24 patients with a CAP with a mean age of 75 ± 8 years. Two patients died in-hospital, with no additional deaths at 30 days. The rate of ISR was 25%, with estimated rates of TLR of 2.6% (3 years) and 17.8% (5 years). The median survival was 55.6 months, with survival at 10 years estimated to be 30.9%. Eight patients received a PTFE covered stent for CAA with a mean age of 59 ± 15 years with no in-hospital or 30-day mortality. Median follow-up of 49 months showed no evidence of TLR. The all-cause mortality was 12% at 1 year and 38% at 3 years.

CONCLUSIONS

PTFE covered stents is an effective option in patients with CAP and CAA. The long-term outcomes may be related to the pathology of the disease rather than the stent itself.

Very long-term outcome of coronary covered stents: a report from the SCAAR registry

AIMS

Covered stents are mostly used for coronary perforations with a high risk of early adverse events; however, their long-term outcome is unknown. The aim of this study was to elucidate the short- and long-term outcome of patients treated with covered stents compared to all other stented patients.

METHODS AND RESULTS

The Swedish national registries from 2005-2017 disclosed 265 patients who had received 366 covered stents. Their outcomes were compared to all other stented patients (197,948) who had received 320,784 stents. Compared to regular stents, covered stents showed significant differences (p<0.001) in the short and long term in relation to in-stent restenosis (ISR), target lesion revascularisation (TLR), re-infarction (MI), re-PCI and mortality, the rates of which were all higher. The higher mortality was concentrated within the first month, as a landmark analysis at that time point, adjusted for age and procedural indication, demonstrated no future difference in mortality (HR 1.02 [0.78-1.33], p=0.877). Stent thrombosis (ST) within one year was reported to be higher in covered stents than in other stents. However, no ST was reported in equine pericardial covered stents.

CONCLUSIONS

This observational study including the entire Swedish population shows that patients receiving covered stents have a significantly higher risk of all adverse events. Reassuringly, in the long term, mortality appears to be similar to that in other stented patients.

Novel approach to coronary artery perforation repair

Coronary artery perforation (CAP) during percutaneous coronary intervention is a rare but serious complication. Treatment options of CAP include prolonged balloon inflation, covered stent, and coil embolization. Although most cases of CAP can be treated with prolonged balloon inflation, some cases, especially Ellis grade III CAP require covered stents or coiling. Covered stents may require a large bore guide catheter and have a high rate of restenosis, which can be a limiting factor in patients with severe peripheral arterial disease. Coil embolization is generally used in distal CAP because coiling in the proximal vessels results in a large territory of infarction. We present a case of an Ellis grade III CAP during rotational atherectomy successfully treated with a novel coiling technique whereby the thrombogenic coil extends through the perforation outside of the vessel, and the intraarterial portion of the coil is excluded from the lumen by drug-eluting stent placement over the proximal portion of the coil.

Multiple coronary and cerebral aneurysms in a patient with chronic thromboangiitis

A 73-year-old man had multiple coronary aneurysms that resulted in acute myocardial infarction on the day before surgery for cerebral aneurysms. Emergent coronary angiography revealed that the lesion that caused the myocardial infarction was a distal left circumflex artery, and two huge coronary aneurysms were also found in the left circumflex artery. A two-stage treatment strategy was planned, including coronary aneurysm surgery, followed by cerebral aneurysm surgery. He underwent coronary artery aneurysmorrhaphy with closure of the ostia of the afferent and efferent arteries, and coronary artery bypass grafting with a saphenous vein graft applied to the left circumflex artery. The pathological findings suggested chronic thromboangiitis, as the inflammatory cells were observed to have infiltrated the coronary artery wall. The tissue remodeling of the aneurysmal wall indicated a positive response to tenascin C. We report a case of multiple coronary aneurysms, focusing on the pathological findings. <Learning objective: Only few reports have described coronary aneurysms related to inflammatory, atherosclerotic, and connective tissue diseases. This report describes the simultaneous occurrence of coronary and cerebral artery aneurysms, focusing on the histopathological findings. The patient's histopathological examination revealed a positive response to tenascin C, which suggested tissue remodeling of the aneurysmal wall and chronic thromboangiitis.>.

Acute and long-term outcomes after polytetrafluoroethylene or pericardium covered stenting for grade 3 coronary artery perforations: Insights from G3-CAP registry

BACKGROUND

Covered stent (CS) implantation is considered a useful device in the setting of Grade III Coronary Perforation (G3CP), one of the most harmful PCI complication. However, data regarding efficacy of this device and clinical outcomes are still limited.

METHODS AND RESULTS

From 1993 to 2015, among 97,779 patients from 9 European centres undergoing PCI, 224 patients had G3CP (0.23%), and 102 patients were managed with CS implantation (96 with PTFE, 6 with pericardium). Device oriented composite endpoint (DOCE), a composite of cardiac death, target lesion revascularization, and stent thrombosis (ST) in-hospital and at long term follow-up were evaluated. G3-CP perforations were successfully sealed with CS in 88 patients (86.3%) with need of intraprocedural pericardiocentesis in one-third of cases. Protamine as heparin reversal agent was administered in 36 (35%) of cases. The cumulative incidence of in-hospital DOCE were 16.6% (17/102): death 14.7%, TLR 2.9%, ST 3.9%. At long-term follow-up (mean 42 ± 38 months), DOCE rates occurred in 19.7%: death 7.4%, TLR 11%, and ST 6.2%. Indication to Dual Antiplatelet Therapy (DAPT) was lifelong in 20% of cases, 1 to 6 months in 22.5% and 12-months in 57.5% without differences in long-term DOCE before and after DAPT interruption (8.0 vs. 6.6%, respectively, P = 0.20).

CONCLUSIONS

Use of CS was successful in sealing grade 3 coronary artery perforations in the majority of cases. Beside the high rate of clinical events at short and long-term, ST remains the leading cause of device failure.

Percutaneous Coronary Intervention of Saphenous Vein Graft

BACKGROUND

Percutaneous coronary intervention (PCI) of saphenous vein grafts (SVGs) has historically been associated with a high risk of adverse ischemic events, but there is a paucity of contemporary data on the second-generation drug-eluting stent use within SVG, and the relative importance of high platelet reactivity (HPR) in SVG PCI versus native lesion PCI is unknown. We studied ischemic and bleeding events after SVG PCI and their association with HPR.

METHODS AND RESULTS

Subjects in the prospective, multicenter ADAPT-DES study (Assessment of Dual Antiplatelet Therapy With Drug-Eluting Stents) were stratified according to whether they had PCI of an SVG or a non-SVG lesion. Two-year outcomes were compared between groups using univariate and multivariable Cox proportional hazards models. HPR was defined as on-clopidogrel P2Y12 platelet reaction units >208 as measured by the VerifyNow assay; major adverse cardiac events were defined as the composite of cardiac death, myocardial infarction, or stent thrombosis. Among 8582 subjects in ADAPT-DES, 405 (4.7%) had SVG PCI. SVG PCI was independently associated with a higher 2-year risk of major adverse cardiac events (adjusted hazard ratio, 2.34; 95% confidence interval, 1.69-3.23; P<0.0001), ischemia-driven target vessel revascularization (adjusted hazard ratio, 1.82; 95% confidence interval, 1.37-2.42; P<0.0001), and stent thrombosis (adjusted hazard ratio, 2.26; 95% confidence interval, 1.42-3.59; P=0.0006), but not of bleeding (adjusted hazard ratio, 0.99; 95% confidence interval, 0.68-1.46; P=0.97). There was no statistical interaction between HPR and SVG PCI in regard to major adverse cardiac events (adjusted P_interaction=0.99).

CONCLUSIONS

SVG PCI is associated with a considerably higher risk of 2-year adverse ischemic events, with HPR conferring similar risk in SVG and non-SVG PCI. More potent and longer antiplatelet therapy may be beneficial for patients undergoing SVG PCI.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00638794.

Current State of the Art in Approaches to Saphenous Vein Graft Interventions

Saphenous vein grafts (SVGs), used during coronary artery bypass graft surgery for severe coronary artery disease, are prone to degeneration and occlusion, leading to poor long-term patency compared with arterial grafts. Interventions used to treat SVG disease are susceptible to high rates of periprocedural MI and no-reflow. To minimise complications seen with these interventions, proper stents, embolic protection devices (EPDs) and pharmacological selection are crucial. Regarding stent selection, evidence has demonstrated superiority of drug-eluting stents over bare-metal stents in SVG intervention. The ACCF/AHA/SCA American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines and the Society for Cardiovascular Angiography and Interventions guidelines recommend the use of EPDs during SVG intervention to decrease the risk of periprocedural MI, distal embolisation and no-reflow. The optimal pharmacological treatment for slow or no-reflow remains unclear, but various vasodilators show promise.

Drug-eluting stents versus bare-metal stents for acute coronary syndrome

BACKGROUND

Approximately 3.7 million people died from acute coronary syndrome worldwide in 2012. Acute coronary syndrome, also known as myocardial infarction or unstable angina pectoris, is caused by a sudden blockage of the blood supplied to the heart muscle. Percutaneous coronary intervention is often used for acute coronary syndrome, but previous systematic reviews on the effects of drug-eluting stents compared with bare-metal stents have shown conflicting results with regard to myocardial infarction; have not fully taken account of the risk of random and systematic errors; and have not included all relevant randomised clinical trials.

OBJECTIVES

To assess the benefits and harms of drug-eluting stents versus bare-metal stents in people with acute coronary syndrome.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, LILACS, SCI-EXPANDED, and BIOSIS from their inception to January 2017. We also searched two clinical trials registers, the European Medicines Agency and the US Food and Drug Administration databases, and pharmaceutical company websites. In addition, we searched the reference lists of review articles and relevant trials.

SELECTION CRITERIA

Randomised clinical trials assessing the effects of drug-eluting stents versus bare-metal stents for acute coronary syndrome. We included trials irrespective of publication type, status, date, or language.

DATA COLLECTION AND ANALYSIS

We followed our published protocol and the methodological recommendations of Cochrane. Two review authors independently extracted data. We assessed the risks of systematic error by bias domains. We conducted Trial Sequential Analyses to control the risks of random errors. Our primary outcomes were all-cause mortality, major cardiovascular events, serious adverse events, and quality of life. Our secondary outcomes were angina, cardiovascular mortality, and myocardial infarction. Our primary assessment time point was at maximum follow-up. We assessed the quality of the evidence by the GRADE approach.

MAIN RESULTS

We included 25 trials randomising a total of 12,503 participants. All trials were at high risk of bias, and the quality of evidence according to GRADE was low to very low. We included 22 trials where the participants presented with ST-elevation myocardial infarction, 1 trial where participants presented with non-ST-elevation myocardial infarction, and 2 trials where participants presented with a mix of acute coronary syndromes.Meta-analyses at maximum follow-up showed no evidence of a difference when comparing drug-eluting stents with bare-metal stents on the risk of all-cause mortality or major cardiovascular events. The absolute risk of death was 6.97% in the drug-eluting stents group compared with 7.74% in the bare-metal stents group based on the risk ratio (RR) of 0.90 (95% confidence interval (CI) 0.78 to 1.03, 11,250 participants, 21 trials/22 comparisons, low-quality evidence). The absolute risk of a major cardiovascular event was 6.36% in the drug-eluting stents group compared with 6.63% in the bare-metal stents group based on the RR of 0.96 (95% CI 0.83 to 1.11, 10,939 participants, 19 trials/20 comparisons, very low-quality evidence). The results of Trial Sequential Analysis showed that we did not have sufficient information to confirm or reject our anticipated risk ratio reduction of 10% on either all-cause mortality or major cardiovascular events at maximum follow-up.Meta-analyses at maximum follow-up showed evidence of a benefit when comparing drug-eluting stents with bare-metal stents on the risk of a serious adverse event. The absolute risk of a serious adverse event was 18.04% in the drug-eluting stents group compared with 23.01% in the bare-metal stents group based on the RR of 0.80 (95% CI 0.74 to 0.86, 11,724 participants, 22 trials/23 comparisons, low-quality evidence), and Trial Sequential Analysis confirmed this result. When assessing each specific type of adverse event included in the serious adverse event outcome separately, the majority of the events were target vessel revascularisation. When target vessel revascularisation was analysed separately, meta-analysis showed evidence of a benefit of drug-eluting stents, and Trial Sequential Analysis confirmed this result.Meta-analyses at maximum follow-up showed no evidence of a difference when comparing drug-eluting stents with bare-metal stents on the risk of cardiovascular mortality (RR 0.91, 95% CI 0.76 to 1.09, 9248 participants, 14 trials/15 comparisons, very low-quality evidence) or myocardial infarction (RR 0.98, 95% CI 0.82 to 1.18, 10,217 participants, 18 trials/19 comparisons, very low-quality evidence). The results of the Trial Sequential Analysis showed that we had insufficient information to confirm or reject our anticipated risk ratio reduction of 10% on cardiovascular mortality and myocardial infarction.No trials reported results on quality of life or angina.

AUTHORS' CONCLUSIONS

The current evidence suggests that drug-eluting stents may lead to fewer serious adverse events compared with bare-metal stents without increasing the risk of all-cause mortality or major cardiovascular events. However, our Trial Sequential Analysis showed that there currently was not enough information to assess a risk ratio reduction of 10% for all-cause mortality, major cardiovascular events, cardiovascular mortality, or myocardial infarction, and there were no data on quality of life or angina. The evidence in this review was of low to very low quality, and the true result may depart substantially from the results presented in this review.More randomised clinical trials with low risk of bias and low risks of random errors are needed if the benefits and harms of drug-eluting stents for acute coronary syndrome are to be assessed properly. More data are needed on the outcomes all-cause mortality, major cardiovascular events, quality of life, and angina to reduce the risk of random error.

Coronary balloon angioplasty, stents, and scaffolds

Since the first coronary angioplasty on Sept 16, 1977, the field of percutaneous coronary intervention has evolved rapidly. Now marking its 40th anniversary, percutaneous coronary intervention has become one of the most common medical procedures worldwide. Much of this progress has been due to the iteration and improvement of angioplasty technologies. Balloon angioplasty was limited by unpredictable procedural outcomes due to vessel dissection and recoil, and a high rate of restenosis. The introduction of stents resulted in more stable early results and lower rates of restenosis, although early stent thrombosis and neointimal hyperplasia causing vessel renarrowing were key limitations. Drug-eluting stents delivering antiproliferative agents significantly lowered the rates of restenosis, permitting widespread use of percutaneous coronary intervention in more advanced and complex disease. Although fully bioresorbable scaffolds have the potential to further improve long-term outcomes, they have not yet achieved results equivalent to those of conventional metallic drug-eluting stents in the early years after implantation. Progress in catheter technology did not occur in isolation, and the success of percutaneous coronary intervention is also due to important advances in intracoronary imaging, and adjunct pharmacotherapy-each of which is reviewed in other papers in this Series.

Coronary covered stents

Covered stents offer an effective bail-out strategy in vessel perforations, are an alternative to surgery for the exclusion of coronary aneurysms, and have a potential role in the treatment of friable embolisation-prone plaques. The aim of this manuscript is to offer an overview of currently available platforms and to report results obtained in prior studies.

A convenient technique for live-cell observation on the surface of polytetrafluoroethylene with a phase-contrast microscope

Phase-contrast microscopy is a convenient technique for live-cell observation on the surface of materials with high optical transmittance. Here, we demonstrate a novel technique to observe living cells on the surface of materials with low optical transmittance, such as polytetrafluoroethylene (PTFE), which are widely used in biomaterials for blood-contacting devices. The surface of a cover glass was coated with a thin PTFE layer with sufficient transmittance, thereby enabling the observation of living cells on the PTFE surface with a phase-contrast microscope.

Myocardial Ischemia Caused by Subepicardial Hematoma

Background Bleeding from bypass anastomosis leakage occurs early after coronary artery bypass grafting. Later, once the anastomosis is covered by intima, spontaneous bleeding is unlikely.

Case Description A 63-year-old male patient developed a pseudoaneurysm-like, subepicardial late-term bleeding resulting in a hematoma that compromised coronary artery flow by increasing extracoronary pressure. This resulted in severe angina pectoris (Canadian Cardiovascular Society IV) and myocardial ischemia within the affected area. After surgical removal of the hematoma and repair of the anastomosis, the patient's symptoms disappeared and no signs of myocardial ischemia were present.

Conclusion Surgical removal is an efficient therapy for subepicardial hematoma inducing myocardial ischemia.

Saphenous Vein Graft Interventions

Saphenous vein graft interventions compose a small but important subset of percutaneous coronary revascularization. Because of their unique biology, percutaneous angioplasty and stenting require tailored patient and lesion selection and modification of intervention technique to optimize outcomes. The use of embolic protection and appropriate adjunctive pharmacology can help minimize periprocedural complications, such as the no-reflow phenomenon. Recommendations for best practice in saphenous vein graft interventions continue to evolve with emerging research and therapy.

Short-Term and Long-Term Outcomes After Polytetrafluoroethylene-Covered Stent Implantation for the Treatment of Coronary Perforation

This study sought to evaluate the short-term and 3-year outcomes of polytetrafluoroethylene-covered stent (PCS) for patients with coronary perforation. Implantation of a PCS has improved the immediate clinical outcomes of patients with coronary perforation. However, there are few reports regarding long-term outcomes. We evaluated a total of 57 patients who were treated with PCS for coronary perforation from April 2004 to March 2015 at a single high-volume center in Japan. Landmark analysis was performed at 30 days to determine short-term and long-term outcomes. Major adverse cardiac events (MACE) were defined as death, myocardial infarction, target vessel revascularization, and requirement for surgical repair. Of 285 patients who experienced coronary perforation, 57 patients (20%) were treated with PCS. The MACE rates were 28% at 30 days, 22% at 1 year, and 38% at 3 years. 30-day MACE was mainly driven by high rates of myocardial infarction (18%) and surgical repair (16%). The rates of target lesion revascularization were 8% and 12% at 1 and 3 years, respectively. Definite stent thrombosis was reported in 2 patients during the follow-up period. In conclusion, despite the relatively high incidence of MACE during early stage of follow-up, implantation of a PCS provides acceptable late clinical outcomes.

Comparison of pathology of chronic total occlusion with and without coronary artery bypass graft

AIMS

The aim of our study was to investigate chronic total occlusion (CTO) in human coronary arteries to clarify the difference between CTO with prior coronary artery bypass graft (CABG) and those without prior CABG.

METHODS AND RESULTS

A total of 95 CTO lesions from 82 patients (61.6 ± 14.0 years, male 87.8%) were divided into the following three groups: CTO with CABG (n = 34) (CTO+CABG), CTO without CABG--of long-duration (n = 49) (LD-CTO) and short-duration (n = 12) (SD-CTO). A histopathological comparison of the plaque characteristics of CTO, proximal and distal lumen morphology, and negative remodelling between groups was performed. A total of 1127 sections were evaluated. Differences in plaque characteristics were observed between groups as follows: necrotic core area was highest in SD-CTO (18.6%) (LD-CTO: 7.8%; CTO+CABG: 4.5%; P = 0.02); calcified area was greatest in CTO+CABG (29.2%) (LD-CTO: 16.8%; SD-CTO: 12.1%; P = 0.009); and negative remodelling was least in SD-CTO [remodelling index (RI) 0.86] [CTO+CABG (RI): 0.72 and LD-CTO (RI): 0.68; P < 0.001]. Approximately 50% of proximal lumens showed characteristics of abrupt closure, whereas the majority of distal lumen patterns were tapered (79%) (P < 0.0001).

CONCLUSION

These pathological differences in calcification, negative remodelling, and presence of necrotic core along with proximal and distal tapering, which has been associated with greater success, help explain the differences in success rates of percutaneous coronary intervention in CTO patients with and without CABG.

Degenerated Saphenous Vein Graft Intervention: Should We Target the Native Vessel instead?

Coronary interventions of degenerated saphenous vein grafts (SVGs) continue to present a management challenge. Although repeat coronary artery bypass grafting (CABG) remains a significant risk factor for operative mortality, percutaneous coronary intervention (PCI) is still associated with a high risk for periprocedural events. There is a lack of consensus on the optimal treatment strategy for patients with severe stenosis of SVGs. It is imperative to review the characteristics of native versus SVG disease, risk factors for complications after SVG intervention, procedural treatment strategies important to the decision on which therapeutic strategy to follow, and measures to mitigate the risks of periprocedural complications.

Management of Complications During Saphenous Vein Graft Interventions

Because of greater patient comorbidities, more diffusely diseased vessels, and the greater possibility of mechanical complications, saphenous vein graft interventions are fraught with complications. The greatest risk is a higher risk of periprocedural myocardial infarction due to distal embolization of microemboli. The risk for noreflow in a patient with concomitant native critical vessel disease can have grave consequences. Minimizing the risk of periprocedural myocardial infarction with the use of distal embolic protection, understanding the role of adjunctive pharmacotherapy, and learning how to manage less common but serious mechanical complications during saphenous vein graft interventions are important to ensure optimal patient outcomes.

The use of polytetrafluoroethylene to facilitate the vascular access in recurrent melanoma to limbs

INTRODUCTION

Melanoma with recurrent loco-regional metastases to limbs often makes difficult a second surgical approach because of the adhesions affecting the vascular access. Our aim was to evaluate whether the placement of a polytetrafluoroethylene (PTFE) membrane around vessels might facilitate a surgical re-approach.

PRESENTATION OF CASE

We reported a case of a 64-year-old male with a melanoma on the left foot who developed in transit metastases after LND. While performing the inguinopelvic LND we coated the iliac vessels with PTFE patch to facilitate the vascular access in case of re-intervention for a ILP. In the second surgical approach we made a cutaneous incision in the left iliac region and we proceeded through the subcutaneous tissue until detection of iliac vessels, more clearly visible because of the PTFE patch fixed around vascular walls to minimize adhesions. We removed the PTFE coating and easily performed arteriotomy and venotomy for the completion of the ILP.

DISCUSSION

This case report seems to demonstrate the efficacy of a PTFE membrane applied in a patient around iliac vessels during inguinopelvic dissection, to reduce adhesion density. In fact this membrane provided a barrier to adhesions of the iliac vessels, decreasing the risk of vascular injury thereby facilitating a subsequent vascular access. Re-coating of the iliac vessels with PTFE could be preparatory to a better identification of the vascular structures in cases of a surgical re-approach.

CONCLUSION

The use of PTFE effectively simplifies the second approach to vessels in event of a melanoma metastasizing to limbs.

Coronary perforation in the drug-eluting stent era: incidence, risk factors, management and outcome: the UK experience

AIMS

Coronary perforation during percutaneous coronary intervention (PCI) is associated with a high risk of mortality and morbidity. However there has been little data on perforation in the current era despite significant changes in PCI practice. We set out to identify incidence, risk factors and management strategies of coronary perforation in the current era.

METHODS AND RESULTS

We performed a retrospective analysis of the Manchester Heart Centre PCI database from June 2004 to May 2008. Detailed analysis of all cases of suspected perforation was undertaken by case note and angiographic review. Demographic data was collected regarding all patients undergoing intervention. A total of 12,729 coronary lesions were treated in 7,903 patients over four years, during which drug-eluting stent (DES) uptake was 77%. The incidence of perforation was 0.56% (44/12,729). Perforation was associated with an inpatient mortality of 15.9% (7/44). Factors associated with perforation were female sex (p=0.003), increasing age (p<0.01), coronary calcification (p=0.003), use of a cutting balloon (p<0.001) or atheroablation (p<0.001), and treatment of a chronic total occlusion (p<0.01). Factors associated with death after perforation were non-elective procedure (p=0.036) and pericardial drain insertion (p<0.001).

CONCLUSIONS

Despite treatment of more complex disease, the incidence of coronary perforation has not increased. Major perforations (Ellis class III) are associated with a high rate of emergency coronary artery bypass graft (CABG) and death. Endovascular treatments allow sealing of the perforation in most cases and deaths occur primarily as a result of cardiogenic shock due to occlusion of the culprit artery. Patient risk factors associated with perforation should be considered when planning or performing PCI.

Bilateral vertebral artery dissecting aneurysms presenting with subarachnoid hemorrhage treated by staged coil trapping and covered stents graft

The treatment of bilateral vertebral artery dissecting aneurysms (VADAs) presenting with subarachnoid hemorrhage (SAH) is still challenging. The authors report a rare case of bilateral VADA treated with coil trapping of ruptured VADA and covered stents implantation after multiple unsuccessful stent assisted coiling of the contralateral unruptured VADA. A 44-year-old woman was admitted to our hospital because of severe headache and sudden stuporous consciousness. Brain CT showed thick SAH and intraventricular hemorrhage. Cerebral angiography demonstrated bilateral VADA. Based on the SAH pattern and aneurysm configurations, the right VADA was considered ruptured. This was trapped with endovascular coils without difficulty. One month later, the contralateral unruptured VADA was protected using a stent-within-a-stent technique, but marked enlargement of the left VADA was detected by 8-months follow-up angiography. Subsequently two times coil packing for pseudosacs resulted in near complete occlusion of left VADA. However, it continued to grow. Covered stents graft below the posterior inferior cerebellar artery (PICA) origin and a coronary stent implantation across the origin of the PICA resulted in near complete obliteration of the VADA. Covered stent graft can be used as a last therapeutic option for the management of VADA, which requires absolute preservation of VA flow.

Saphenous vein graft intervention

Saphenous vein grafts are commonly used conduits for surgical revascularization of coronary arteries but are associated with poor long-term patency rates. Percutaneous revascularization of saphenous vein grafts is associated with worse clinical outcomes including higher rates of in-stent restenosis, target vessel revascularization, myocardial infarction, and death compared with percutaneous coronary intervention of native coronary arteries. Use of embolic protection devices is a Class I indication according to the American College of Cardiology/American Heart Association guidelines to decrease the risk of distal embolization, no-reflow, and periprocedural myocardial infarction. Nonetheless, these devices are underused in clinical practice. Various pharmacological agents are available that may also reduce the risk of or mitigate the consequences of no-reflow. Covered stents do not decrease the rates of periprocedural myocardial infarction and restenosis. Most available evidence supports treatment with drug-eluting stents in this high-risk lesion subset to reduce angiographic and clinical restenosis, although large, randomized trials comparing drug-eluting stents and bare-metal stents are needed.