The everolimus eluting Synergy MegatronTM drug-eluting stent platform: Early outcomes from the European Synergy MegatronTM Implanters' Registry.

BACKGROUND: The Synergy MegatronTM is an everolimus-drug eluting stent that may offer advantages in the treatment of aorto-ostial disease and large proximal vessels. AIMS: To report the short- to medium-term clinical outcomes from the European Synergy MegatronTM Implanters' Registry. METHODS: This registry was an investigator-initiated study conducted at 14 European centers. The primary outcome was target lesion failure (TLF), defined as the composite of cardiovascular death, target vessel myocardial infarction (MI), and target lesion revascularisation. RESULTS: Five hundred seventy-five patients underwent PCI with MegatronTM between 2019 and 2021. Patients were 69 ± 12 years old, 26% had diabetes mellitus, 24% had moderate-severe left ventricular impairment and 59% presented with an acute coronary syndrome. 15% were deemed prohibitively high risk for surgical revascularisation. The target vessel involved the left main stem in 55%, the ostium of the RCA in 13% and was a true bifurcation (Medina 1,1,1) in 50%.  At 1 year, TLF was observed in 40 patients, with 26 (65%) occurring within the first 30 days. The cumulative incidence of TLF was 4.5% at 30 days and 8.6% (95% CI 6.3-11.7) at 1 year. The incidence of stent thrombosis was 0.5% with no late stent thromboses. By multivariate analysis, the strongest independent predictors of TLF were severe left ventricular impairment (HR 3.43, 95% CI: 1.67-6.76, p < 0.001) and a target vessel involving the left main (HR 4.00 95% CI 1.81-10.15 p = 0.001). CONCLUSIONS: Use of the Synergy MegatronTM everolimus eluting stent in a 'real-world' setting shows favorable outcomes at 30 days and 1 year.

Potent endothelial progenitor cell-conditioned media-related anti-apoptotic, cardiotrophic, and pro-angiogenic effects post-myocardial infarction are mediated by insulin-like growth factor-1.

AIMS: We have previously reported the cardioprotective effects of endothelial progenitor cell (EPC)-conditioned media (CM) therapy post-myocardial infarction (MI). In the present study, we have determined the insulin-like growth factor-1 (IGF-1) contribution to EPC CM effects on cardiomyocyte survival, contractility, and angiogenesis in vivo. METHODS AND RESULTS: Conditioned media from porcine EPC were administered intracoronary in the presence and absence of specific neutralizing antibodies to IGF-1 or control IgG in a porcine model of MI. X-vivo (non-conditioned) medium was used as a control. Functional, histological, and biochemical parameters were evaluated at 24 h and 8-week post-therapy. Conditioned media therapy significantly abrogated infarct zone (IZ) apoptosis, hypocontractility, and impaired left ventricular (LV) relaxation observed in control infarcts acutely (24 h post-MI). At 8 weeks following treatment, CM therapy augmented LV contractility and relaxation, IZ angiogenesis and inhibited infarct size expansion, wall expansion, and wall thinning. All of these acute and chronic beneficial effects of CM therapy were vitiated by neutralizing antibodies to IGF-1 but not by control IgG. Moreover, the addition of neutralizing IGF-1 antibody to control medium had no effect on these structural or functional changes in the heart post-treatment. CONCLUSION: Insulin-like growth factor-1 within the EPC CM mediates potent acute myocardial repair and chronic remodelling effects post-MI. These findings may provide a rationale for comparative trials of specific growth factors vs. current progenitor cell strategies.

Endovascular management of acute limb ischemia.

Despite major advances in pharmacologic and endovascular therapies, acute limb ischemia (ALI) continues to result in significant morbidity and mortality. The incidence of ALI may be as high as 13-17 cases per 100,000 people per year, with mortality rates approaching 18% in some series. This review will address the contemporary endovascular management of ALI encompassing pharmacologic and percutaneous interventional treatment strategies.

Thrombin stimulates smooth muscle cell differentiation from peripheral blood mononuclear cells via protease-activated receptor-1, RhoA, and myocardin.

RATIONALE: Smooth muscle precursor cells have previously been reported to reside in bone marrow and in the circulation, but little is currently known regarding the proximate stimuli for smooth muscle cell differentiation of these putative progenitors. OBJECTIVE: Because local thrombin generation occurs as an initial response to vascular injury, we hypothesized that thrombin may influence the differentiation of circulating smooth muscle progenitor cells. METHODS AND RESULTS: Peripheral blood mononuclear cells were cultured on type I collagen using a protocol optimized to stimulate smooth muscle cell outgrowth. Thrombin-stimulated upregulation of the transcription factor myocardin and smooth muscle myosin heavy chain, and both were inhibited by hirudin or the RhoA inhibitor Y27632. After 10 days of culture, smooth muscle outgrowth colonies formed, which stained positive for alpha-smooth muscle actin, smooth muscle myosin heavy chain, and calponin, in addition to having a contractile response to 100 nmol/L angiotensin II. Coincubation of peripheral blood mononuclear cells with thrombin, 10 micromol/L protease-activated receptor-1, but not protease-activated receptor-4 activating peptide significantly increased the number of smooth muscle outgrowth colonies formed. Thrombin-induced enhancement of smooth muscle outgrowth colony formation was inhibited by hirudin, Y27632, and an antibody against protease-activated receptor-1. CONCLUSIONS: These data illustrate a novel thrombin-induced pathway for smooth muscle differentiation from putative smooth muscle progenitors in peripheral blood.

Advances in endovascular treatment of critical limb ischemia.

Critical limb ischemia (CLI) represents the most severe clinical manifestation of peripheral arterial disease. In the absence of timely revascularization, CLI carries high risk of mortality and amputation. Over the past decade, endovascular revascularization has rapidly become the preferred primary treatment strategy for CLI, especially for the treatment of below-the-knee disease. Advances in percutaneous devices and techniques have expanded the spectrum of patients with CLI who are deemed candidates for revascularization. This review will focus on advances in endovascular options for the treatment of CLI, in particular for below-the-knee disease.

Carotid stent fracture and restenosis management.

We report an unusual case of asymptomatic accelerated right carotid artery in-stent restenosis in a patient referred for revascularization of a de novo stenosis of her left internal carotid artery.

Carotid artery stenting after carotid endarterectomy.

Atherosclerotic carotid artery disease remains an important cause of cerebrovascular ischemic disease. We present a patient with residual stenosis of the distal internal carotid artery following carotid endarterectomy that was treated with stenting. The case highlights the potential complimentary benefits of carotid endarterectomy and carotid stenting.

Protective cranial implant caps for macaques.

BACKGROUND: Neuroscience studies with macaque monkeys may require cranial implants to stabilize the head or gain access to the brain for scientific purposes. Wound management that promotes healing after the cranial implant surgery in non-human primates can be difficult as it is not necessarily possible to cover the wound margins. NEW METHOD: Here, we developed an easily modifiable head cap that protects the sutured skin margins after cranial implant surgery and contributes to wound healing. The protective head cap was developed in response to monkeys picking at sutured skin margins around an implant, complicating healing. The user-friendly protective cap, made from Klarity- R™ Sheet (3.2 mm thick with 36 % or 42 % perforation) is affixed to the implant post-surgically. Once secured and while the monkey is still anesthetized, the plastic sheeting is molded around the implant. The protective head cap restricts the monkey's finger access to its' wound margins while allowing air to circulate to promote wound healing. RESULTS AND COMPARISON WITH EXISTING METHODS: Across two UK primate facilities, the protective head cap promoted wound healing. In monkeys that did not wear the head cap, re-suturing was necessary in ∼30 % of cases. In contrast, none of the monkeys that wore the head cap required re-suturing. The monkeys wearing the head cap also had reduced numbers of days of prescribed antibiotics and analgesia. CONCLUSION: This bespoken, easily adaptable, protective head cap supports postoperative wound healing, and enhances the welfare of monkeys involved in neuroscience research.

Chimney Stenting During Transcatheter Aortic Valve Implantation.

Acute coronary artery obstruction is a rare but life-threatening complication of transcatheter aortic valve implantation. In patients at risk of coronary artery obstruction, pre-emptive coronary artery protection with a coronary wire, balloon or stent provides a bailout treatment option. The authors describe the steps involved in performing chimney stenting and summarise the short- and long-term outcome data associated with this technique.

Linear radiofrequency microcatheter ablation guided by phased array intracardiac echocardiography combined with temperature decay.

BACKGROUND: Fluoroscopy-guided catheter placement is limited in its ability to determine electrode-endocardial contact and involves radiation exposure. We hypothesized that (1) intracardiac echocardiography (ICE) would provide superior assessment of linear electrode contact compared to fluoroscopy and (2) slow temperature decay upon discontinuation of the radiofrequency current (time for temperature to fall 90% after a 10-second test application of the radiofrequency current T90) would indicate optimal electrode-myocardial contact. METHODS: Sixty endocardial lesions were created in the atria and ventricles of six goats by simultaneous delivery of the radiofrequency current through two linear electrodes of a microcatheter with a central interelectrode thermocouple. Catheter placement was guided by fluoroscopy. A 7.5-MHz ICE transducer in the right atrium or ventricle assessed electrode contact. T90 and previously reported parameters of electrode contact and lesion formation were recorded. Histomorphometry was performed on the lesions. RESULTS: T90 was 4.27 +/- 4.98 seconds. Lesion depth significantly correlated with ICE assessment of electrode contact (r = 0.56, P = 0.001); T90 upon radiofrequency current offset (r = 0.48, P = 0.008), impedance fall upon radiofrequency current onset (r = 0.37, P = 0.008), bipolar pacing threshold preablation (r =-0.56, P = 0.001), bipolar electrogram amplitude preablation (r = 0.43, P = 0.02), but not with fluoroscopic assessment of the electrode contact (r = 0.18, n.s.). For the prediction of achieving a lesion depth of >2 mm, a T90 of >4.0 seconds yielded a specificity of 86% and a sensitivity of 52%, ICE yielded a specificity and sensitivity of 58% and 68%, respectively, while the specificity and sensitivity of fluoroscopy were 26% and 68%, respectively. Both ICE and T90 provide additional clinical relevance during guidance of cardiac microcatheter ablation.

An unusual cervical mass.

Head and neck masses are usually indicative of infectious, neoplastic, or congenital entities. Most head and neck masses are related to local or regional disease, although systemic neoplastic disease can present in the cervical area. We present an interesting case report of a young woman with a neck mass caused by an organism most commonly associated with sexually transmitted infections, and not with the more common causes of cervical head and neck masses.

Les masses à la tête au cou sont souvent indicatrices de problèmes infectieux, néoplasiques ou congénitaux. La plupart de ces masses sont liées à une maladie locale ou régionale, même si elles peuvent être la manifestation de maladies néoplasiques systémiques. Les auteurs présentent le cas intéressant d'une jeune femme ayant une masse cervicale causée par un organisme généralement associé aux infections transmises sexuellement et non aux causes habituelles des masses au cou et à la tête.

Patient Disposition and Clinical Outcome After Referral to a Dedicated TAVI Clinic.

Introduction: Transcatheter aortic valve implantation (TAVI) is the standard of care for the majority of patients with severe symptomatic aortic stenosis (AS) at excessive-, high- and intermediate-surgical risk. A proportion of patients referred for TAVI do not undergo the procedure and proceed with an alternate treatment strategy. There is scarce data describing the final treatment allocation of such patients. Hence, we sought to evaluate the final treatment allocation of patients referred for TAVI in contemporary practice. Methods: We performed a single center prospective observational study, including all patients referred to our institution for treatment of severe aortic stenosis between February 2014 and August 2017. Baseline demographic and clinical data were recorded. Patients were categorized according to treatment allocation: TAVI, surgical aortic valve replacement (SAVR) or optimal medical therapy (OMT). Clinical outcomes were adjudicated according to VARC-2 definitions. All patients were discussed at a dedicated Heart Team meeting. Results: Total of 245 patients were referred for assessment to a dedicated TAVI clinic during the study period. Patients with moderate (N = 32; 13.1%) and asymptomatic (N = 31; 13.1%) AS were excluded. Subsequently, 53.9% (N = 132) received TAVI, 12.7% (N =31) were managed with OMT, and 7.3% (N =18) had SAVR. Reasons for OMT included primarily: patient's preference (N = 12; 38.7%); excessive surgical risk (N = 4; 12.9%) and severe frailty (N = 5; 16.1%). Reasons for surgical referral included low surgical risk (N = 11; 61.1%), excessive annulus size (N = 5; 27.8%), and aortic root dilatation (N = 2; 11.1%). Patients proceeding to SAVR had lower surgical risk than those in either the OMT or TAVI cohorts (P < 0.001). Mean STS score in SAVR group was 2.2 ± 1.3 vs. 4.5 ± 2.4 in OMT cohort and 6.1 ± 4.9 in TAVI cohort. Six-month all-cause mortality was 16.7, 19.4, and 9.3% among those receiving SAVR, OMT, and TAVI, respectively. Conclusions: Almost half of all patients with severe AS referred to a dedicated TAVI clinic did not receive a TAVI. A considerable proportion of patients were reclassified as moderate AS (13%), were asymptomatic (13%), or intervention was determined to be futile (13%) due to advanced frailty. Early detection and increased awareness of valvular heart disease are required to increase the number of patients that can benefit from TAVI.

Anchor-balloon technique to facilitate stent delivery via the GuideLiner catheter in percutaneous coronary intervention.

AIM: The GuideLiner (GL) is a widely used catheter primarily in complex percutaneous coronary intervention (PCI). Deep seating of the GL and distal stent placement may be facilitated by the anchor-balloon technique (ABT). METHODS: We aimed to prospectively analyze procedural details, technical success, complications and in-hospital outcome in patients who underwent PCI using the GL catheter and the ABT. RESULTS: A total of 118 patients underwent PCI with the aid of the GL and ABT. Procedure success rate was 95% (112/118) and only seven patients (5.9%) encountered complications. ABT was indicated and successfully used in 29 patients (25%). CONCLUSION: GL and ABT successfully aided stent delivery in unfavorable and heavily calcified lesions which otherwise may have been considered unsuitable for PCI.

Carotid artery stenting for recurrent carotid artery restenosis after previous ipsilateral carotid artery endarterectomy or stenting: a report from the National Cardiovascular Data Registry.

OBJECTIVES: The purpose of this study was to evaluate and compare outcomes of patients undergoing carotid artery stenting (CAS) for ipsilateral restenosis, after either previous CAS or carotid artery endarterectomy (CEA) (CAS-R group), with those of patients who had CAS performed for de novo carotid atherosclerotic stenosis (CAS-DN group). BACKGROUND: Therapeutic revascularization strategies to reduce stroke include CAS and CEA. Limited data exist concerning the outcomes of CAS in the setting of previous ipsilateral carotid revascularization. METHODS: Patients enrolled in the CARE (Carotid Artery Revascularization and Endarterectomy) registry who underwent CAS were identified and separated into 2 groups: those undergoing CAS after previous ipsilateral CEA or CAS (CAS-R group, n = 1,996) and those who had CAS performed for de novo atherosclerotic carotid stenosis (CAS-DN group, n = 10,122). We analyzed the clinical and procedural factors associated with CAS-R and CAS-DN between January 1, 2005, and October 8, 2012. Propensity score matching using 19 clinical and 9 procedural characteristics was used, yielding 1,756 patients in each CAS cohort. RESULTS: The primary endpoint composite of in-hospital death or stroke or myocardial infarction (MI) occurred less often in the CAS-R compared with CAS-DN patients (1.9% vs. 3.2%; p = 0.019). In-hospital adverse cerebrovascular events (stroke or transient ischemic attack) occurred less frequently in the CAS-R cohort (2.2% vs. 3.6%; p < 0.001). However, there was no significant difference in the composite of death, stroke, or MI at 30 days between both groups. CONCLUSIONS: Patients who underwent CAS for restenosis after previous ipsilateral revascularization had lower periprocedural adverse event rates and comparable 30-day adverse event rates compared with CAS for de novo carotid artery stenosis.

Transcatheter aortic valve implantation and cerebrovascular events: the current state of the art.

Transcatheter aortic valve implantation (TAVI) has revolutionized the care of high-risk patients with severe calcific aortic stenosis. Those considered at high or prohibitive risk of major adverse outcomes with open surgical aortic valve replacement may now be offered an alternative less-invasive therapy. Despite the rapid evolution and clinical application of this new technology, recent studies have raised concerns about adverse cerebrovascular event rates in patients undergoing TAVI. In this review, we explore the current data both in relation to procedure-related silent cerebrovascular ischemic events, as well as clinically apparent stroke. The timing of neurological events and their prognostic implications are also examined. Finally, potential mechanisms of TAVI-related cerebrovascular injury are described, in addition to efforts to minimize their occurrence.

Modern antiplatelet agents in coronary artery disease.

Dual antiplatelet therapy is well recognized in the prevention of thrombotic complications of acute coronary syndrome and percutaneous coronary interventions. Despite clinical benefits of aspirin and clopidogrel therapy, a number of limitations curtail their efficacy: slow onset of action, variability in platelet inhibitory response and potential drug-drug interactions. Furthermore, the single platelet-activation pathway targeted by these agents allows continued platelet activation via other pathways, ensuring incomplete protection against ischemic events, thus, underscoring the need for alternate antiplatelet treatment strategies. A number of novel antiplatelet agents are currently in advance development and many have established superior effects on platelet inhibition, clinical outcomes and safety profile than clopidogrel in high-risk patients. The aim of this review is to provide an overview of the current status of P2Y12 receptor inhibition and PAR-1 antagonists in determining a future strategy for individualized antiplatelet therapy.

Atherosclerotic renal artery stenosis and renal artery stenting: an evolving therapeutic option.

Atherosclerotic renal artery stenosis is a common clinical problem for which the optimal therapeutic strategy remains to be defined. However, renal artery stenting procedures have significantly increased as one approach to treat this clinical problem. Despite improvements in device design and technical performance of the procedure, the benefits and results of randomized clinical trials of renal artery stenting as a therapy remain confusing. Understanding the epidemiology, pathophysiology and natural history of renal artery stenosis are central to improving the outcomes of renal artery stenting. Developing both noninvasive and invasive predictive tools to better identify which patient will respond to renal revascularization will also be beneficial. In this article, we will present an overview of atherosclerotic renal artery disease. The results of renal artery stenting will be discussed and from this, the available noninvasive and invasive tools available to assess the clinical and hemodynamic significance of renal artery stenosis will be presented.

Improved protocol for processing stented porcine coronary arteries for immunostaining.

Percutaneous coronary intervention has resulted in a paradigm shift in the treatment of coronary artery disease and myocardial infarction. However, neither bare-metal stents nor polymer-coated drug-eluting stents represent ideal therapies at this time due to the undesired in-stent stenosis or delayed thrombosis. Hence there is pressing clinical need for greater understanding of the cellular mechanisms involved. It is hoped that this in turn will provide insight into designing and developing the next generation of stents. Although immunohistochemistry and immunofluorescence are appropriate tools in understanding the molecular histology, performing these techniques on stented blood vessels is technically challenging because of poor permeability of antibodies into the stented blood vessels which are embedded in methacrylate-based resins and inadequate image resolution due to autofluorescence. Hence there is a need to develop techniques which can facilitate immunohistochemistry/immunofluorescence procedures on stented blood vessel cross-sections. In this study we describe an improved protocol for processing stented porcine coronary arteries for immunostaining with smooth muscle cell, endothelial cell, monocyte and macrophage markers. We first identified the optimal conditions for resin embedding of stented artery and cross sectioned the vessels using high speed precision wafering diamond blade. The sections were then ground using two levels of water sandpaper on a Metaserve 2000 grinder to achieve the desired thickness. For immunostaining, we developed a novel deplasticization protocol which favors optimal antibody permeabilization. Our protocol not only provides feasibility of improved immunostaining of stented artery sections but also results in high quality images.