Lower expression of neutrophil adhesion molecule indicates less vessel wall injury and might explain lower restenosis rate after cutting balloon angioplasty

The role of inflammation in percutaneous coronary intervention, from balloon angioplasty to drug eluting stents

The role of inflammation in percutaneous coronary intervention (PCI) has been investigated in numerous studies. Both pre-PCI and post-PCI inflammatory status have been demonstrated to be linked with patient outcomes. C-reactive protein continues to be the most studied inflammatory biomarker, while a growing number of additional biomarkers, including cytokines and immune cells, are being assessed. As insights are gained into the complexities of the inflammatory response to PCI, it becomes evident that a targeted approach is necessary to ensure optimal patient outcomes. Here, we review the biomarkers that can predict patient outcomes following PCI and specifically how they differ for balloon angioplasty, bare metal stents and drug eluting stents. A specific focus is given to human studies and periprocedural inflammation rather than inflammation associated with myocardial infarction.

Contemporary percutaneous management of coronary calcification: current status and future directions

Severe coronary artery calcification is one of the greatest challenges in attaining success in percutaneous coronary intervention, limiting acute and long-term results. In many cases, plaque preparation is a critical prerequisite for delivery of devices across calcific stenoses and also to achieve adequate luminal dimensions. Recent advances in intracoronary imaging and adjunctive technologies now allow the operator to select the most appropriate strategy in each individual case. In this review, we will revisit the distinct advantages of a complete assessment of coronary artery calcification with imaging and application of appropriate and contemporary plaque modification technologies in achieving durable results in this complex lesion subset.

State-of-the-Art Endovascular Therapies for the Femoropopliteal Segment: Are We There Yet?

Peripheral arterial disease is an increasingly prevalent condition with significant associated morbidity, mortality, and health care expenditure. Endovascular interventions are appropriate for most patients with either ongoing symptoms of intermittent claudication despite lifestyle and medical optimization or chronic limb-threatening ischemia. The femoropopliteal segment is the most common arterial culprit responsible for claudication and the most commonly revascularized segment. Endovascular approaches to revascularization of the femoropopliteal segment are advancing with an evolving landscape of techniques for arterial access, device-based therapies, vessel preparation, and intraprocedural imaging. These advances have been marked by debate and controversy, notably related to the safety of paclitaxel-based devices and necessity of atherectomy. In this review, we provide a critical overview of the current evidence, practice patterns, emerging evidence, and technological advances for endovascular intervention of the femoropopliteal arterial segment.

Roles of MicroRNAs in Peripheral Artery In-Stent Restenosis after Endovascular Treatment

Endovascular repair including percutaneous transluminal angioplasty (PTA) and stent implantation has become the standard approach for the treatment of peripheral arterial disease; however, restenosis is still the main limited complication for the long-term success of the endovascular repair. Endothelial denudation and regeneration, inflammatory response, and neointimal hyperplasia are major pathological processes occurring during in-stent restenosis (ISR). MicroRNAs exhibit great potential in regulating several vascular biological events in different cell types and have been identified as novel therapeutic targets as well as biomarkers for ISR prevention. This review summarized recent experimental and clinical studies on the role of miRNAs in ISR modification, with the aim of unraveling the underlying mechanism and potential therapeutic strategy of ISR.

Finite element analysis of cutting balloon expansion in a calcified artery model of circular angle 180°: Effects of balloon-to-diameter ratio and number of blades facing calcification on potential calcification fracturing and perforation reduction

Calcified artery lesions cause stent under-expansion and increase the risk of in-stent restenosis and stent thrombosis. Cutting balloons facilitate the fracturing of calcification prior to stent implantation, although vessel dissection and perforation are potential issues. In clinical practice, calcifications having maximum calcium angles ≤ 180° are rarely fractured during conventional balloon angioplasty. We hypothesize that the lesion/device diameter ratio and the number of blades facing a non-circular calcified lesion may be crucial for fracturing the calcification while avoiding vessel injury. The geometries of the cutting balloons were constructed and their finite-element models were generated by folding and wrapping the balloon model. Numerical simulations were performed for balloons with five different diameters and two types of blade directions in a 180° calcification model. The calcification expansion ability was distinctly higher when two blades faced the calcification than when one blade did. Moreover, when two blades faced the calcification model, larger maximum principal stresses were generated in the calcification even when using undersized balloons with diameters reduced by 0.25 or 0.5 mm from the reference diameter, when compared with the case where one blade faced the calcified model and a balloon of diameter equal to the reference diameter was used. When two blades faced the calcification, smaller stresses were generated in the artery adjacent to the calcification; further, the maximum stress generated in the artery model adjacent to the calcification under the rated pressure of 12 atm when employing undersized balloons was smaller than that when only one blade faced the calcification and when lesion-identical balloon diameters were used under a nominal pressure of 6 atm. Our study suggested that undersized balloons of diameters 0.25 or 0.5 mm less than the reference diameter might be effective in not only expanding the calcified lesion but also reducing the risk of dissection.

The evidence to support the use of focal force balloon technology to improve outcomes in the treatment of lower extremity arterial occlusive disease

Despite recent advances in endovascular therapy of lower extremity atherosclerotic disease, mainly driven through drug eluting balloon angioplasty, treatment of complex lesions remains challenging. Drug-eluting balloons work less well in heavily calcified lesions and in particular long lesions often require bail-out stenting. Lesion preparation, as a stand-alone treatment or before delivering antiproliferative therapy or scaffolding, has gained increased recognition in recent years. Focal force or other specialty balloons are designed to prepare complex lesions to improve acute technical success and, ideally, long term patency of the vessel. There are numerous dedicated balloons on the market that use different modes of action to prepare the lesions. The current review focuses on mechanistic insights and the evidence behind those specialty balloons.

Usefulness of paclitaxel-releasing high-pressure balloon associated with cutting balloon angioplasty for treatment of outflow stenoses of failing hemodialysis arteriovenous shunts

AIM

To evaluate the technical and clinical success, primary patency (PP) and complications of angioplasty performed with paclitaxel-coated balloon (PCBs) associated with cutting balloon and for the treatment of the outflow stenoses of failing hemodialysis arteriovenous shunt.

MATERIAL AND METHODS

From September 2014 to September 2015, 50 patients with 66 stenoses were registered. Vascular accesses were autogenous (n = 20) and prosthetic (n = 30). Stenosis were documented during follow-up with routine echo-color Doppler, clinical evaluation and in the remaining incidentally during fistulography. Angioplasty was performed with cutting balloon and afterward with PCB. The mean follow-up time was 8 months (range 6-15 months). Technical success, clinical success, primary patency and complications were registered.

RESULTS

Technical success was 100 %. Clinical success was 94.7 %. Primary patency rate was 87.7 %; in five patients, a significant re-stenosis (≥50 %) was registered. A residual asymptomatic stenosis (<30 %) was registered in four cases (7 %). No major complications were registered.

CONCLUSIONS

A short-term patency benefit may be obtained including PCB in angioplasty treatment of failing hemodialysis arteriovenous shunts.

Cutting Balloon Angioplasty for the Treatment of In-Stent Restenosis in Diabetics: A Matched Comparison of 6 Months' Outcome With Conventional Balloon Angioplasty

Ranging from 24% to 55%, angiographic in-stent restenosis (ISR) rates in diabetics are higher than the 17% to 28% rates observed in nondiabetics. There are controversies regarding optimal treatment for ISR. Recently, cutting balloon angioplasty (CBA) emerged as a tool in management. The authors assessed the hypothesis that CBA has advantages over conventional percutaneous transluminal balloon angioplasty (PTCA) in treatment of ISR in diabetics. CBA or PTCA was applied to 165 diabetics (267 ISR lesions) in their institution. With a computer algorithm, an attempt was made to match each lesion in the CBA group with a corresponding lesion in the PTCA group. The lesion pairs should match with respect to the patients' age and gender, type of target vessel and stent, reference vessel diameter, and baseline minimal lumen diameter (MLD). Following the matching process, 55 ISR lesion pairs were identified. Baseline patient characteristics were similar among the groups (p=NS). There was no difference in the in-hospital major adverse cardiac events (MACE) between the groups, whereas MACE at follow up was significantly lower in the CBA group compared to the PTCA group (CBA, 20.0% vs PTCA, 43.6%, p<0.05). The recurrent ISR rate was significantly lower in the CBA group compared to the PTCA group (CBA, 27.3% vs PTCA, 49.1%; p<0.05). Also, a diffuse pattern of recurrence was more common in lesions treated with PTCA, whereas a focal pattern of recur- rence was more common in the CBA group. The minimal luminal diameter at follow-up, the acute gain, and net gain were significantly higher in the group of lesions treated with CBA than in the PTCA group. In addition, a significantly higher late loss and loss index at follow-up were observed in the PTCA group compared to the CBA group. CBA has advantages over PTCA in treatment of diabetic patients with ISR, with better immediate and follow-up angiographic outcomes, and better follow-up clinical outcome.

Developing control points for halal slaughtering of poultry

Halal (permissible or lawful) poultry meat production must meet industry, economic, and production needs, and government health requirements without compromising the Islamic religious requirements derived from the Qur'an and the Hadiths (the actions and sayings of the Prophet Muhammad, peace and blessings be upon him). Halal certification authorities may vary in their interpretation of these teachings, which leads to differences in halal slaughter requirements. The current study proposes 6 control points (CP) for halal poultry meat production based on the most commonly used halal production systems. CP 1 describes what is allowed and prohibited, such as blood and animal manure, and feed ingredients for halal poultry meat production. CP 2 describes the requirements for humane handling during lairage. CP 3 describes different methods for immobilizing poultry, when immobilization is used, such as water bath stunning. CP 4 describes the importance of intention, details of the halal slaughter, and the equipment permitted. CP 5 and CP 6 describe the requirements after the neck cut has been made such as the time needed before the carcasses can enter the scalding tank, and the potential for meat adulteration with fecal residues and blood. It is important to note that the proposed halal CP program is presented as a starting point for any individual halal certifying body to improve its practices.

The influence of composition and location on the toughness of human atherosclerotic femoral plaque tissue

The toughness of femoral atherosclerotic tissue is of pivotal importance to understanding the mechanism of luminal expansion during cutting balloon angioplasty (CBA) in the peripheral vessels. Furthermore, the ability to relate this parameter to plaque composition, pathological inclusions and location within the femoral vessels would allow for the improvement of existing CBA technology and for the stratification of patient treatment based on the predicted fracture response of the plaque tissue to CBA. Such information may lead to a reduction in clinically observed complications, an improvement in trial results and an increased adoption of the CBA technique to reduce vessel trauma and further endovascular treatment uptake. This study characterises the toughness of atherosclerotic plaque extracted from the femoral arteries of ten patients using a lubricated guillotine cutting test to determine the critical energy release rate. This information is related to the location that the plaque section was removed from within the femoral vessels and the composition of the plaque tissue, determined using Fourier Transform InfraRed spectroscopy, to establish the influence of location and composition on the toughness of the plaque tissue. Scanning electron microscopy (SEM) is employed to examine the fracture surfaces of the sections to determine the contribution of tissue morphology to toughness. Toughness results exhibit large inter and intra patient and location variance with values ranging far above and below the toughness of healthy porcine arterial tissue (Range: 1330-3035 for location and 140-4560J/m(2) for patients). No significant difference in mean toughness is observed between patients or location. However, the composition parameter representing the calcified tissue content of the plaque correlates significantly with sample toughness (r=0.949, p<0.001). SEM reveals the presence of large calcified regions in the toughest sections that are absent from the least tough sections. Regression analysis highlights the potential of employing the calcified tissue content of the plaque as a preoperative tool for predicting the fracture response of a target lesion to CBA (R(2)=0.885, p<0.001).

STATEMENT OF SIGNIFICANCE

This study addresses a gap in current knowledge regarding the influence of plaque location, composition and morphology on the toughness of human femoral plaque tissue. Such information is of great importance to the continued improvement of endovascular treatments, particularly cutting balloon angioplasty (CBA), which require experimentally derived data as a framework for assessing clinical cases and advancing medical devices. This study identifies that femoral plaque tissue exhibits large inter and intra patient and location variance regarding tissue toughness. Increasing calcified plaque content is demonstrated to correlate significantly with increasing toughness. This highlights the potential for predicting target lesion toughness which may lead to an increased adoption of the CBA technique and also further the uptake of endovascular treatment.

Targeting Wnt-Frizzled signaling in cardiovascular diseases

Wnts are secreted glycoproteins implicated in biological processes ranging from embryonic cardiac development to uncontrolled cell proliferation in diseased conditions. Cardiovascular disease is a major cause of morbidity and mortality worldwide. Phenotypic modulation of vascular smooth muscle cells, migration and proliferation in intimal layer and increased extracellular matrix production are some of the known hallmarks of cardiovascular pathologies. Heterogeneity associated with the binding of Wnts to their transmembrane receptors, Frizzled, and coreceptors low density lipoprotein-receptor-related protein is indeed intriguing. Nuclear-cytoplasmic shuttling of beta-catenin and activation of transcriptional factors, lymphoid enhancer factor and T cell activation factor leading to target gene activation has remained elusive. Our review highlights the emerging role of Wnt-Frizzled signaling in cardiovascular diseases. Overall, the pathway appears to be an attractive therapeutic target in identifying susceptible individuals at risk of developing restenosis/other vascular pathologies in the near future.

Soluble CD40 ligand stimulates CD40-dependent activation of the β2 integrin Mac-1 and protein kinase C zeda (PKCζ) in neutrophils: implications for neutrophil-platelet interactions and neutrophil oxidative burst

Recent work has revealed an essential involvement of soluble CD40L (sCD40L) in inflammation and vascular disease. Activated platelets are the major source of sCD40L, which has been implicated in platelet and leukocyte activation, although its exact functional impact on leukocyte-platelet interactions and the underlying mechanisms remain undefined. We aimed to determine the impact and the mechanisms of sCD40L on neutrophils. We studied neutrophil interactions with activated, surface-adherent platelets as a model for leukocyte recruitment to the sites of injury. Our data show that CD40L contributes to neutrophil firm adhesion to and transmigration across activated surface-adherent platelets, possibly through two potential mechanisms. One involves the direct interaction of ligand-receptor (CD40L-CD40), i.e., platelet surface CD40L interaction with neutrophil CD40; another involves an indirect mechanism, i.e. soluble CD40L stimulates activation of the leukocyte-specific β2 integrin Mac-1 in neutrophils and thereby further promotes neutrophil adhesion and migration. Activation of the integrin Mac-1 is known to be critical for mediating neutrophil adhesion and migration. sCD40L activated Mac-1 in neutrophils and enhanced neutrophil-platelet interactions in wild-type neutrophils, but failed to elicit such responses in CD40-deficient neutrophils. Furthermore, our data show that the protein kinase C zeta (PKCζ) is critically required for sCD40L-induced Mac-1 activation and neutrophil adhesive function. sCD40L strongly stimulated the focal clustering of Mac-1 (CD11b) and the colocalization of Mac-1 with PKCζ in wild-type neutrophils, but had minimal effect in CD40-deficient neutrophils. Blocking PKCζ completely inhibited sCD40L-induced neutrophil firm adhesion. Moreover, sCD40L strongly stimulates neutrophil oxidative burst via CD40-dependent activation of PI3K/NF-KB, but independent of Mac-1 and PKCζ. These findings may contribute to a better understanding of the underlying mechanisms by which sCD40L/CD40 pathway contributes to inflammation and vascular diseases.

MicroRNA and vascular remodelling in acute vascular injury and pulmonary vascular remodelling

Vascular remodelling is an integral pathological process central to a number of cardiovascular diseases. The complex interplay between distinct cell populations in the vessel wall following vascular injury leads to inflammation, cellular dysfunction, pro-growth signals in the smooth muscle cell (SMC) compartment, and the acquisition of a synthetic phenotype. Although the signals for vascular remodelling are diverse in different pathological contexts, SMC proliferation and migration are consistently observed. It is therefore critical to elucidate key mechanisms central to these processes. MicroRNAs (miRNAs) are small non-coding sequences of RNA that have the capacity to regulate many genes, pathways, and complex biological networks within cells, acting either alone or in concert with one another. In diseases such as cancer and cardiac disease, the role of miRNA in disease pathogenesis has been documented in detail. In contrast, despite a great deal of interest in miRNA, relatively few studies have directly assessed the role of miRNA in vascular remodelling. The potential for modulation of miRNA to achieve therapeutic benefits in this setting is attractive. Here, we focus on the role of miRNA in vascular inflammation and remodelling associated with acute vascular injury (vein graft disease, angioplasty restenosis, and in-stent restenosis) as well as in vascular remodelling associated with the development of pulmonary arterial hypertension.

Vascular inflammation and repair: implications for re-endothelialization, restenosis, and stent thrombosis

The cellular and molecular processes that control vascular injury responses after percutaneous coronary intervention involve a complex interplay among vascular cells and progenitor cells that control arterial remodeling, neointimal proliferation, and re-endothelialization. Drug-eluting stents (DES) improve the efficacy of percutaneous coronary intervention by modulating vascular inflammation and preventing neointimal proliferation and restenosis. Although positive effects of DES reduce inflammation and restenosis, negative effects delay re-endothelialization and impair endothelial function. Delayed re-endothelialization and impaired endothelial function are linked to stent thrombosis and adverse clinical outcomes after DES use. Compared with bare-metal stents, DES also differentially modulate mobilization, homing, and differentiation of vascular progenitor cells involved in re-endothelialization and neointimal proliferation. The effects of DES on vascular inflammation and repair directly impact clinical outcomes with these devices and dictate requirements for extended-duration dual antiplatelet therapy.

Neutrophils and clinical outcomes in patients with acute coronary syndromes and/or cardiac revascularisation. A systematic review on more than 34,000 subjects

Some studies have suggested that high levels of total white blood cell (WBC) count and C-reactive protein (CRP) may be considered as independent prognostic factors in patients with acute coronary syndromes (ACS) and/or after cardiac revascularisation by percutaneous coronary intervention or coronary artery bypass grafting surgery. Evidence on the role of neutrophils in cardiovascular disease is less compelling. Therefore, we conducted a systematic review of the literature with the aim of identifying all the available evidence to clarify the role of neutrophils (absolute or relative count, neutrophil/lymphocyte ratio) as a prognostic risk factor in patients with ACS and/or cardiac revascularisation. All published studies evaluating the role of neutrophils as a risk factor for clinical outcomes were assessed using the MEDLINE and EMBASE databases. Study selection, data extraction and validity assessment was performed independently by two reviewers. Twenty-one studies (17 of which had positive results) for a total of more than 34,000 patients were included. Ten of 13 studies in ACS patients found that neutrophils measured on-admission are related to mortality rate and/or to major adverse clinical events. A predictive value of neutrophils after cardiac revascularisation procedures was reported in seven out of eight studies. Most of the studies showed that neutrophils were independent predictors of cardiovascular outcomes when analysed concomitantly with other markers of inflammation (WBC, CRP). The findings of our systematic review highlight the potential application of this inexpensive and readily available inflammatory marker for risk stratification in patients with ACS and/or cardiac revascularisation.

Stenting of complex lesions: an overview

Contemporary management of coronary artery disease relies increasingly on percutaneous techniques combined with medical therapy. Although percutaneous coronary intervention (PCI) can be performed successfully in most lesions, several difficult lesion subsets continue to present unique technical challenges. These complex lesions may be classified according to anatomic criteria, including extensive calcification, thrombus, and chronic occlusions, or by location, such as bifurcations, saphenous vein grafts and unprotected left main. PCI of these lesions often requires novel devices, such as drug-eluting stents, hydrophilic guidewires, distal protection balloons or filters, thrombectomy catheters, rotational atherectomy, and cutting balloons. An integrated approach that combines these devices with specialized techniques and adjunctive pharmacologic agents has greatly improved PCI success rates for these complex lesions.

Activation of matrix metalloproteinase-9 is associated with mobilization of bone marrow-derived cells after coronary stent implantation

BACKGROUND

After stent-related vascular injury, an inflammatory response triggers the mobilization of bone marrow-derived stem cells, including both endothelial and smooth muscle progenitors, leading to re-endothelialization as well as restenosis. It has been postulated that neutrophil-released matrix metalloproteinase-9 (MMP-9) induces stem cell mobilization.

AIM

To elucidate the mechanistic link between inflammation and stem cell mobilization after coronary stenting.

METHODS

In 31 patients undergoing coronary stenting, we serially measured activated Mac-1 on the surface of neutrophils and active MMP-9 levels in the coronary sinus blood plasma, and the number of circulating CD34-positive cells in the peripheral blood.

RESULTS

After bare-metal stent implantation (n=21), significant increases in the numbers of CD34-positive cells (maximum on post-procedure day 7, P<0.001), activated Mac-1 (at 48 h, P<0.001), and active MMP-9 levels (at 24h, P<0.001) were observed. However, these changes were absent after sirolimus-eluting stent implantation (n=10). In overall patients, the numbers of CD34-positive cells on day 7 (R=0.58, P<0.01) and activated Mac-1 at 48 h (R=0.58, P<0.01) were both correlated with active MMP-9 levels at 24h. Stimulation of activated Mac-1 on the surface of isolated human neutrophils produced active MMP-9 release in vitro.

CONCLUSIONS

These results suggest that stent-induced activation of Mac-1 on the surface of neutrophils might trigger their MMP-9 release, possibly leading to the mobilization of bone marrow-derived stem cells. These reactions were substantially inhibited by sirolimus-eluting stents.

Comparison of plain balloon and cutting balloon angioplasty for the treatment of restenosis with drug-eluting stents vs bare metal stents

BACKGROUND

The efficacy of cutting or plain balloon angioplasty (CBA or PBA) has not been analyzed for the treatment of drug-eluting stent (DES) restenosis vs bare metal stent (BMS) restenosis.

METHODS AND RESULTS

The 252 in-stent restenosis (ISR) lesions in 224 consecutive patients treated by CBA (n=167) or PBA (n=85) between July 2002 and December 2007 were analyzed. At 6-month angiographic and 12-month clinical follow-up, CBA and PBA showed similar efficacies: repeat-ISR (37.0% vs 37.8%, P=0.90), late loss (0.62+/-0.60 vs 0.61+/-0.47 mm, P=0.92), and target lesion revascularization (18.3% vs 22.4%, P=0.50). This comparable efficacy was maintained for treatment in the DES-ISR and BMS-ISR subgroups. However, target lesion-related myocardial infarction (n=9) occurred more frequently in the CBA than in the PBA arm (6.2% vs 0%, P=0.03), most of which developed early after ISR treatment (n=7; 54+/-26 days). Independent predictors of repeat-ISR were diffuse ISR and smaller pretreatment minimal lumen diameter, both of which might imply heavier plaque burden in the ISR group.

CONCLUSIONS

Plain or cutting balloon angioplasty for ISR seems to be comparable, as the angiographic or clinical endpoints were not affected by initial stent type but by parameters related to the plaque burden of the ISR lesion. However, CBA might be associated with higher risk of myocardial infarction than PBA, suggesting more attention to dual-antiplatelet therapy after its use for ISR.

Ultrahigh-Pressure Angioplasty versus the Peripheral Cutting Balloon™ for Treatment of Stenoses in Autogenous Fistulas: Comparison of Immediate Results

Purpose

To compare the immediate results of ultrahigh-pressure (UHP) balloons vs. peripheral cutting balloons (PCB) for the treatment of stenoses associated with autogenous fistulas using intra-access blood flow measurements.

Materials and Methods

This prospective randomized study consisted of 22 hemodialysis (HD) patients with autogenous fistulas who had decreased intra-access blood flow (<500 mL/min). All patients underwent a fistulogram and intraprocedural blood flow measurements. Patients were randomized once into two groups; one group undergoing UHP angioplasty and the second group undergoing PCB angioplasty. Randomization occurred once after the diagnostic fistulogram and each patient in each arm only underwent percutaneous transluminal angioplasty with either UHP or PCB. The study cohort consisted of 12 patients in the UHP group and 10 patients in the PCB group. Data collected included fistula anatomy, degree of stenosis, length of stenosis, balloon specifications and residual stenosis.

Results

The 22 study patients underwent 35 angioplasty procedures; 23 in the UHP group (12 patients) and 12 in the PCB group (10 patients). The technical success rate was 91%. The pre-intervention mean blood flow was 288 mL/min in the UHP group and 391 mL/min in the PCB group. The post-intervention mean blood flow was 613 mL/min in the UHP group and 606 mL/min in the PCB group. The mean increase in blood flow was 325.8 mL/min in the UHP group and 213 mL/min in the PCB group. This represents a relative mean increase in blood flow of 253% in the UHP group and 85% in the PCB group. An unpaired t-test showed there was no significant difference between the groups with respect to pre-flow, post-flow, and mean and relative mean increase in flow. There were two failures; one in the UHP group and one in the PCB group. There was one minor complication (2.8%) but no major complications.

Conclusions

In this small group of HD patients with autogenous fistulas our comparison of UHP to the PCB demonstrated that the immediate results, as determined by measurement of intra-access blood flow, were equivalent. Further long-term follow-up will be required to determine the longevity of these results

[Management of anastomotic stenosis after lower extremity bypass surgery with cutting balloon angioplasty]

PURPOSE

Conventional balloon angioplasty of anastomotic stenosis following bypass surgery is insufficient at mid- and long-term. However, short-term results with cutting balloon angioplasty (CBA) are satisfactory. The purpose of this study is to determine the long-term results using this technique. Materials and methods. Between January 2002 and January 2006, all patients with anastomotic stenosis more than one month after bypass surgery, shorter than 2 cm and>50%, were referred without randomisation to CBA.

RESULTS

A total of 19 patients with mean age of 63.5 years (55-82 years), 14 males and 5 females, were included. Twenty stenoses (femoral n=15, popliteal n=4 and calf n=1) managed with CBA affected 17 infrainguinal and 2 suprainguinal bypasses. One patient had anastomotic stenoses at both extremities. The rate of technical success aws 100%. Mean follow-up was 32 months (12-42). Three deaths occurred during follow-up. One patient presented with restenosis at 3 months, successfully treated with repeat CBA. No thrombosis or infection was observed.

CONCLUSION

The results with CBA appear persistent and compete favorably with results from surgical repair. A randomized trial would be necessary to confirm these results.

The State of the Art in Pulmonary Vein Stenosis -Diagnosis & Treatment

Pulmonary vein stenosis is a rare but serious complication of pulmonary vein isolation to treat atrial fibrillation. Pulmonary vein angioplasty/stenting has emerged as the treatment of choice for significantly stenotic veins. Guidelines for post ablation evaluation of the pulmonary veins, including the timing and method of surveillance for possible stenosis, the criteria for intervention, the technical aspects of intervention, and finally the surveillance post intervention, are still being developed. The relatively high rate of restenosis after intervention in a subset of patients remains a great challenge. A better understanding of the pathophysiology underlying this syndrome is needed to appropriately answer many of the remaining questions. The goal of this manuscript is to describe what has been learned about this complication and its treatment from a relatively large experience in a single institution over the past decade, and provide a comprehensive review of the existing literature in order to shed as much light on the subject as is possible, while at the same time exposing the areas that need further study.

Adrenomedullin expression in coronary circulation after stent implantation as a prognostic factor for restenosis

The authors determined the changes in adrenomedullin (AM) expression in the coronary circulation of patients with ischemic heart disease who underwent coronary stent implantation. Blood samples were drawn from the coronary sinus before, immediately after and four hours after coronary stent implantation, and plasma levels of AM were measured. AM levels in the coronary sinus blood were significantly increased four hours after stent implantation. On the other hand, in the femoral arterial blood, no significant changes in AM levels were observed. A significant positive correlation was found between AM level in the coronary sinus blood four hours after stent implantation and late loss index six months after the procedure. These results suggest that inflammation after coronary stent implantation induces AM expression, which might play an important role in restenosis after stenting.

Treatment of calcified ostial disease by rotational atherectomy and adjunctive cutting balloon angioplasty prior to stent implantation

Both heavily calcified and ostial lesions are difficult to deal with by percutaneous transluminal coronary angioplasty (PTCA) alone. Acute results are often sub-optimal, complications are more frequent, and long-term results are disappointing. Optimal stent deployment may not be possible unless satisfactory lesion dilatation is achieved and the lesion made more compliant. The use of rotational atherectomy and cutting balloon angioplasty to a calcified ostial lesion in the left circumflex coronary artery prior to stent implantation is reported.

Long-term clinical efficacy of cutting balloon angioplasty followed by bare metal stent implantation for treating ostial left anterior descending artery lesions

BACKGROUND

Drug-eluting stents (DES) are superior to bare metal stents (BMS) for treating ostial left anterior descending artery (LAD) lesions, but DES is not suitable for all patients in real life practice.

HYPOTHESIS

We hypothesize that cutting balloon angioplasty (CBA) followed by BMS (CBA + BMS) for treating ostial LAD lesions is an alternative strategy.

METHODS

In our study, 101 consecutive patients (51 with DES and 50 with CBA + BMS) with ostial LAD stenting were included for retrospective investigation between November 2003 and May 2005. The target vessel diameter was > or =3.0 mm.

RESULTS

We compared the DES group with the CBA + BMS group, the rates of restenosis (10.3% versus 17.9%, p = 0.386), target lesion revascularization (TLR) (5.88% versus 10%, p = 0.487) and major adverse cardiac events (MACE) (7.84% versus 12%, p = 0.525) were similar at 6-8 months angiographic follow-up, but there were higher bleeding events in the DES group (p = 0.033). During a 2-year clinical follow-up, no myocardial infarction occurred in the 2 groups, the rates of TLR (7.84% versus 10%, p = 0.741) and MACE (9.8% versus 12%, p = 0.723) were also similar. The MACE-free survival rate was 90.2% versus 88 % (p = 0.723).

CONCLUSIONS

The CBA + BMS combination has a good long-term clinical effect in the treatment of ostial LAD lesions; it might be an alternative strategy for patients with contraindication for DES implantation, or patients who cannot endure long-term dual antiplatelet medication, or in elderly patients.

The possible role of red blood cell microvesicles in atherosclerosis

The tendency of sickle cells to adhere to the endothelium reflects the surface features not only of the red cells but also of the endothelial cells. Sickle cell disease is a prototype of a condition where the erythrocyte is under stress, ischemic, oxidative, or shear stress, that causes changes in the erythrocyte morphology. This change leads eventually to enhanced erythrocyte-endothelial cell adhesion. Reactive oxygen species generated by cytokine-activated inflammatory cells oxidize lipoproteins such as LDL and lipoprotein(a) within the vessel wall, facilitating uptake of these particles by activated macrophages and smooth muscle cells, with conversion into lipid-laden foam cells. Notably, the membranes of sickle RBCs have undergone excessive cytoskeletal protein thiol oxidation, and sickle RBCs are abnormally prone to vesiculation during mechanical stress in vitro and apparently in vivo. This abnormality was successfully reproduced in normal RBCs by causing stress conditions using PMS-induced stimulation of intracellular superoxide generation, a process similar to that occurring in sickle RBCs. It could be that the generation of reactive oxygen species in atherosclerosis activates red blood cells, and microvesicles of red blood cells are formed, enhancing the activation of the vascular endothelium and leading to vascular inflammation and atherogenesis.

Use of the Angiosculpt Scoring Balloon for Infrapopliteal Lesions in Patients with Critical Limb Ischemia: 1-Year Outcome

The AngioSculpt Scoring Balloon Catheter (AngioScore, Inc., Fremont, CA) is composed of a semicompliant balloon encircled by three nitinol spiral struts providing targeted lesion scoring on balloon inflation. Between April 2005 and April 2006, procedural and follow-up data on 31 patients (mean age 76 years; 54.8% males) endovascularly treated for severe infrapopliteal disease were collected. The AngioSculpt catheter was used to treat 36 complex, tibioperoneal, atherosclerotic lesions. All patients had symptomatic critical limb ischemia (Rutherford 4–5) and single-vessel runoff to the ankle. Complication-free survival at 1 month was the safety end point, whereas primary patency and limb salvage were the efficacy end points evaluated at 1 year. The AngioSculpt balloon was successfully inflated in all 36 target lesions. Eleven patients (35.5%) required additional stenting for minor dissections or suboptimal stenosis reduction. The 1-month complication-free survival was 96.8%. One-year survival, primary patency, and limb salvage rates were 83.9 ± 6.6%, 61.0 ± 9.3%, and 86.3 ± 6.4%, respectively. The 1-year data show the AngioSculpt Scoring Balloon Catheter to be an effective and safe treatment for infrapopliteal, atherosclerotic lesions in patients with critical limb ischemia. However, more patients, a longer follow-up, and randomized studies comparing it with conventional balloon angioplasty and stenting in the infrapopliteal region are required.

CD40 ligand promotes Mac-1 expression, leukocyte recruitment, and neointima formation after vascular injury

High levels of circulating soluble CD40 ligand (sCD40L) are frequently found in patients with hypercholesterolemia, diabetes, ischemic stroke, or acute coronary syndromes, predicting an increased rate of atherosclerotic plaque rupture and restenosis after coronary/carotid interventions. Clinical restenosis is characterized in part by exaggerated neointima formation, but the underlying mechanism remains incompletely understood. This study investigated the role of elevated sCD40L in neointima formation in response to vascular injury in an atherogenic animal model and explored the molecular mechanisms involved. apoE(-/-) mice fed a Western diet developed severe hypercholesterolemia, significant hyperglycemia, and high levels of plasma sCD40L. Neointima formation after carotid denudation injury was exaggerated in the apoE(-/-) mice. In vivo, blocking CD40L with anti-CD40L monoclonal antibody attenuated the early accumulation of Ly-6G(+) neutrophils and Gr-1(+) monocytes (at 3 days) and the late accumulation of Mac-2(+) macrophages (at 28 days) in the denudated arteries; it also reduced the exaggerated neointima formation at 28 days. In vitro, recombinant CD40L stimulated platelet P-selectin and neutrophil Mac-1 expression and platelet-neutrophil co-aggregation and adhesive interaction. These effects were abrogated by anti-CD40L or anti-Mac-1 monoclonal antibody. Moreover, recombinant CD40L stimulated neutrophil oxidative burst and release of matrix metalloproteinase-9 in vitro. We conclude that elevated sCD40L promotes platelet-leukocyte activation and recruitment and neointima formation after arterial injury, potentially through enhancement of platelet P-selectin and leukocyte Mac-1 expression and oxidative activity.

Interleukin-8 as an independent predictor of long-term clinical outcome in patients with coronary artery disease

BACKGROUND

Accumulating evidence suggests that inflammation plays an essential role in the pathogenesis of atherosclerosis and that circulating inflammatory markers predict future cardiovascular events. However, previous studies evaluated the predictive value of only a single cytokine at a time.

AIMS

This study was designed to simultaneously measure plasma levels of multiple cytokines in patients with coronary artery disease and to evaluate their ability to predict long-term prognosis.

METHODS

The study enrolled 158 consecutive patients with angiographically identified stable coronary artery disease. Using the Luminex micro-beads array system, we simultaneously measured plasma levels of the following 10 cytokines: interleukin (IL)-1beta, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, tumor necrosis factor (TNF)-alpha, granulocyte-macrophage colony stimulating factor (GM-CSF) and gamma-interferon (IFN-gamma).

RESULTS

None of the 10 cytokine levels as well as high-sensitive C reactive protein (hs-CRP) was correlated with the severity of coronary artery disease. During a 7-year follow-up period, cardiovascular events occurred in 56 patients (35%). Multi-vessel disease, diabetes, and high levels of all of the 10 measured cytokines and hs-CRP were significant predictors of cardiovascular events in univariate analysis. However, multivariate analysis using multi-vessel disease, diabetes and the levels of all of 10 cytokines and hs-CRP showed that the only independent predictor was IL-8 (RR, 2.98; 95%CI, 1.64-7.24; P=0.0001).

CONCLUSION

IL-8 was the only cytokine that predicted cardiovascular events independent of the other 9 cytokines and hs-CRP. Since IL-8 is a neutrophil chemokine, these results suggest that neutrophil activation may be related to the occurrence of cardiovascular events.

Cutting-balloon angioplasty effectively facilitates the interventional procedure and leads to a low rate of recurrent stenosis in ostial bifurcation coronary lesions: A subgroup analysis of the NICECUT multicenter registry

BACKGROUND

Displacement of plaque is a major concern during coronary intervention of ostial bifurcation lesions. For this reason, angioplasty involves complex stenting procedures, which may trigger development of restenosis in a previously non-diseased parent vessel.

OBJECTIVES

To examine, whether plaque displacement may be prevented by scoring atherosclerotic plaque with a cutting-balloon (CB) stand-alone procedure.

METHODS

Data of patients with Duke E and B type ostial bifurcation lesions (>/=70% stenosis involving a diagonal and/or marginal branch >2 mm deriving from a non-diseased parent vessel), who were treated with CB as stand-alone procedure within the prospective NICECUT multicenter trial were analyzed. Primary endpoint was the rate of binary stenosis and target lesion revascularization (TLR). Secondary endpoints were procedural success and major adverse cardiac events (MACE) at 6-months follow-up.

RESULTS

63 out of 65 lesions (56 patients) were successfully amenable to treatment with CB (96.4% procedural success). 76.9% of patients were successfully treated with CB as a stand-alone procedure, while provisional stenting was necessary in 23.1%. At follow-up, binary stenosis was found in 23.2%, among the total population. Total rate of TLR and MACE were 7.7% and 3.6%, respectively, compared to 4.0% and 2.0% in patients for whom CB stand-alone procedure was feasible, while it was 20.0% and 6.7% for stented lesions.

CONCLUSIONS

CB angioplasty as a stand-alone procedure may facilitate interventional treatment of ostial bifurcation lesions and may help to avoid complex stenting procedures. It is associated with a low rate of binary stenosis and TLR.

Cutting Balloon Angioplasty Versus Standard Balloon Angioplasty for Failing Infra-inguinal Vein Grafts: Comparative Study of Short- and Mid-Term Primary Patency Rates

PURPOSE

To evaluate the results of a recent change in practice in our institution using cutting balloon angioplasty instead of standard balloon angioplasty as the primary treatment for failing infra-inguinal vein bypass grafts.

METHODS

In this nonrandomized cohort study with a historical control, failing infra-inguinal vein grafts were identified at duplex surveillance or clinical examination. Patients had confirmatory arteriography and balloon angioplasty at the same attendance. Interventions proximal or distal to the graft itself and prosthetic grafts were not included. Patients were entered into a duplex graft surveillance program. Initial assessment of technical success was duplex or improvement 4-6 weeks after the primary angioplasty.

RESULTS

Twenty-seven consecutive patients were treated with standard balloon angioplasty, then 11 consecutive patients were treated with cutting balloon angioplasty. Initial technical success was 74% for the standard balloon versus 82% for the cutting balloon. The primary patency rate at 6 months was 16/26 (62%) for standard balloon angioplasty and 8/10 (80%) for cutting balloon angioplasty (p = 0.44). The primary patency rate at 12 months was 9/25 (36%) for standard balloon angioplasty and 5/10 (50%) for cutting balloon angioplasty (p = 0.47).

CONCLUSION

The use of cutting balloons for primary angioplasty of infra-inguinal vein grafts offers no definite advantage over standard balloon angioplasty in this institution or compared with patency rates after standard balloon angioplasty reported elsewhere. Larger multicenter studies would be required to demonstrate whether there was any real difference between the two techniques.

Increased circulating platelet-derived microparticles are associated with stent-induced vascular inflammation

Inflammation as well as platelet activation at the site of local vessel-wall injury plays an essential role in the mechanism of restenosis after Percutaneous coronary intervention (PCI). Platelet-derived microparticles (PDMPs) released from activated platelets are thought to play a role in the inflammatory process, possibly interacting with leukocyte integrin Mac-1. We serially measured circulating PDMPs, high-sensitive C-reactive protein (hs-CRP) and activated Mac-1 on the surface of neutrophils in 61 patients undergoing coronary stenting. PDMPs, hs-CRP and Mac-1 increased after coronary stenting in a time-dependent manner with the maximum response at 48 h in coronary sinus blood (PDMPs: 10.3+/-8.9-32.8+/-13.8 U/ml; P<0.001, hs-CRP: 0.27+/-0.23-1.46+/-0.99 mg/dl; P<0.001, activated Mac-1, 134+/-19% relative increase, P<0.001). PDMPs were correlated with hs-CRP (R=0.58, P<0.001) and the relative increase in Mac-1 (R=0.69, P<0.001) 48 h after coronary stenting. Multiple regression analysis showed that each of PDMPs (R=0.40, P<0.05), hs-CRP (R=0.33, P<0.05) and Mac-1 (R=0.48, P<0.01) was an independent predictor of the late lumen loss. Coronary stenting enhanced circulating PDMPs in association with an inflammatory response in the injured vessel wall. PDMPs may be a useful marker for evaluation of stent-induced inflammatory status and a powerful predictor of restenosis equivalent to activated Mac-1.

Comparison of changes in circulating platelet-derived microparticles and platelet surface P-selectin expression after coronary stent implantation

Platelet-derived microparticles (PDMPs) are released from activated platelets and may participate in the inflammatory process in response to vessel wall injury. This study was designed to compare the clinical significance of circulating PDMPs with that of P-selectin on the platelet membrane surface. In 20 patients with stable angina undergoing coronary stent implantation, circulating PDMPs were serially measured by enzyme-linked immunosorbent assay, and P-selectin expression on the surface of platelets was simultaneously analyzed by flow cytometry. PDMPs increased 24-48 h after coronary stenting in the coronary sinus (8.7 +/- 8.9 to 31.8 +/- 19.8 U/ml, P < 0.001) with a maximum at 48 h. In contrast, the mean channel fluorescence intensity for P-selectin increased 15 min after coronary stenting in the coronary sinus (19.5 +/- 5.6 to 25.2 +/- 7.5, P < 0.01) and remained elevated for 48 h; the changes were less striking in peripheral blood. The relative increase in PDMPs was not correlated with the increase in P-selectin expression at 15 min or 24 h after coronary stenting, but was correlated at 48 h (R = 0.48, P < 0.05). Both circulating PDMPs and P-selectin expression were enhanced in association with stent-induced platelet activation; however, the time course of changes in these two platelet activation markers was different. Therefore, the clinical relevance of circulating PDMPs may differ from that of P-selectin expression on the platelet membrane surface.