Egr-1 functions as a master switch regulator of remote ischemic preconditioning-induced cardioprotection.

Despite improved treatment options myocardial infarction (MI) is still a leading cause of mortality and morbidity worldwide. Remote ischemic preconditioning (RIPC) is a mechanistic process that reduces myocardial infarction size and protects against ischemia reperfusion (I/R) injury. The zinc finger transcription factor early growth response-1 (Egr-1) is integral to the biological response to I/R, as its upregulation mediates the increased expression of inflammatory and prothrombotic processes. We aimed to determine the association and/or role of Egr-1 expression with the molecular mechanisms controlling the cardioprotective effects of RIPC. This study used H9C2 cells in vitro and a rat model of cardiac ischemia reperfusion (I/R) injury. We silenced Egr-1 with DNAzyme (ED5) in vitro and in vivo, before three cycles of RIPC consisting of alternating 5 min hypoxia and normoxia in cells or hind-limb ligation and release in the rat, followed by hypoxic challenge in vitro and I/R injury in vivo. Post-procedure, ED5 administration led to a significant increase in infarct size compared to controls (65.90 ± 2.38% vs. 41.00 ± 2.83%, p < 0.0001) following administration prior to RIPC in vivo, concurrent with decreased plasma IL-6 levels (118.30 ± 4.30 pg/ml vs. 130.50 ± 1.29 pg/ml, p < 0.05), downregulation of the cardioprotective JAK-STAT pathway, and elevated myocardial endothelial dysfunction. In vitro, ED5 administration abrogated IL-6 mRNA expression in H9C2 cells subjected to RIPC (0.95 ± 0.20 vs. 6.08 ± 1.40-fold relative to the control group, p < 0.05), resulting in increase in apoptosis (4.76 ± 0.70% vs. 2.23 ± 0.34%, p < 0.05) and loss of mitochondrial membrane potential (0.57 ± 0.11% vs. 1.0 ± 0.14%-fold relative to control, p < 0.05) in recipient cells receiving preconditioned media from the DNAzyme treated donor cells. This study suggests that Egr-1 functions as a master regulator of remote preconditioning inducing a protective effect against myocardial I/R injury through IL-6-dependent JAK-STAT signaling.

Cost benefit for assessment of intermediate coronary stenosis with fractional flow reserve in public and private sectors in australia.

BACKGROUND: Fractional Flow Reserve (FFR) is a proven technology for guiding percutaneous coronary intervention (PCI), but is not reimbursed despite the fact that it is frequently used to defer PCI. METHODS: Costs incurred with use of FFR were compared in both the public and private sectors with the costs that would have been incurred if the technology was not available using consecutive cases over a two year period in a public teaching hospital and its co-located private hospital. RESULTS: FFR was performed on 143 lesions in 120 patients. FFR was < 0.80 in 37 lesions in 34 patients and 25 underwent PCI while 11 had CABG. It was estimated that without FFR 78 lesions in 70 patients would have had PCI with 17 patients having CABG with 35 additional functional tests. Despite a cost of $A1200 per wire, FFR actually saved money. Mean savings in the public sector were $1200 per patient while in the private sector the savings were $5000 per patient. CONCLUSIONS: FFR use saves money for the Federal Government in the public sector and for the Private Health Funds in the private sector. These financial benefits are seen in addition to the improved outcomes seen with this technology.

Initial experience with the balloon expandable Edwards-SAPIEN Transcatheter Heart Valve in Australia and New Zealand: the SOURCE ANZ registry: outcomes at 30 days and one year.

BACKGROUND: We report the findings of the SOURCE-ANZ registry of the clinical outcomes of the Edwards SAPIEN™ Transcatheter Heart Valve (THV) in the Australian and New Zealand (ANZ) clinical environment. METHODS: This single arm registry of select patients treated in eight centres, represent the initial experience within ANZ with the balloon expandable Edwards SAPIEN THV delivered by transfemoral (TF) and transapical (TA) access. RESULTS: The total enrolment for the study was 132 patients, 63 patients treated by TF, 56 by TA, and 2 patients were withdrawn from the study. The mean ages: 83.7 (TF) and 81.7 (TA), female: 34.3% (TF) and 61.3% (TA), logistic EuroSCORE: 26.8% (TF) and 28.8% (TA), and with procedural success (successful implant without conversion to surgery or death): 92.4% (TF) and 87.1% (TA) (p=0.32). Outcomes were not significantly different between TF and TA implants. These included one year mortality of 13.6% (TF) and 21.7% (TA) (p=0.24), MACCE: 16.7% (TF) and 28.3% (TA) (p=0.12), pacemaker: 4.6% (TF) and 8.3% (TA) (p=0.39), and VARC major vascular complication of 4.6% (TF) and 5.0% (TA) (p=0.91). CONCLUSION: TAVI in the ANZ clinical environment has demonstrated excellent outcomes for both the TA and TF approaches in highly selected patients. These results are consistent with those demonstrated in European, Canadian registries and the pivotal US clinical trials. ACTRN12611001026910.

Current concepts on antiplatelet therapy: focus on the novel thienopyridine and non-thienopyridine agents.

Thienopyridines are a class of drug targeting the platelet adenosine diphosphate (ADP) 2 receptor. They significantly reduce platelet activity and are therefore clinically beneficial in settings where platelet activation is a key pathophysiological feature, particularly myocardial infarction. Ticlopidine, the first of the class introduced to clinical practice, was soon challenged and almost completely replaced by clopidogrel for its better tolerability. More recently, prasugrel and ticagrelor have been shown to provide a more powerful antiplatelet action compared to clopidogrel but at a cost of higher risk of bleeding complications. Cangrelor, a molecule very similar to ticagrelor, is currently being evaluated against clopidogrel. Considering the key balance of ischemic protection and bleeding risk, this paper discusses the background to the development of prasugrel, ticagrelor, and cangrelor and aims to characterise their risk-benefit profile and possible implementation in daily practice.

What is the risk of intensifying platelet inhibition beyond clopidogrel? A systematic review and a critical appraisal of the role of prasugrel.

Thienopyridines are a class of drug targeting the platelet adenosine diphosphate 2 receptor. They have been shown to significantly reduce platelet activity exerting an important role in those clinical settings in which such an effect is beneficial. Ticlopidine was first to be introduced several years ago but it was quickly replaced by clopidogrel as it had a better risk/benefit profile. Recently, prasugrel has been developed and tested in several ex vivo studies and clinical trials showing able to provide a more powerful antiplatelet effect at the expense of a higher risk of bleeding complications. Great debate rose around its recent approval in the US as well as in Europe. This review aims at exploring the development and available clinical data of this third-generation thienopyridine while discussing its practical implementation in routine practice.

Pexelizumab in ischemic heart disease: a systematic review and meta-analysis on 15,196 patients.

OBJECT: Pexelizumab is a humanized monoclonal antibody inhibiting C5 complement. It has been postulated to improve outcomes in patients undergoing coronary artery bypass surgery and urgent reperfusion therapy for ST elevation myocardial infarction. We aimed at evaluating the risk/benefit profile of pexelizumab (bolus + infusion) versus placebo on top of current approaches in the management of patients with ST elevation myocardial infarction or undergoing coronary artery bypass. METHODS: We conducted a search of BioMedCentral, CENTRAL, mRCT, and PubMed without language restrictions (updated October 2007) for randomized controlled trials. Outcomes of interest were the risk of major adverse events (the composite of all-cause death, myocardial infarction, and thromboembolic stroke), the risk of single end points, and heart failure. RESULTS: Seven trials were included (15,196 patients: 7019 patients with ST elevation myocardial infarction and 8177 undergoing coronary bypass surgery). No benefit of adding pexelizumab was found in the overall analysis for major adverse events (OR 0.91 [0.76-1.09]; P = .29], death (OR 0.79 [0.61-1.03], P = .11], myocardial infarction (OR 1.04 [0.89-1.22]; P = .14), stroke (OR 0.95 [0.66-1.38]; P = .8), heart failure (OR1.0 [0.82-1.22]; P = .99), nor in the settings of patients with ST elevation myocardial infarction treated with mechanical or pharmacologic reperfusion therapy. Pexelizumab was associated with a 26% reduction of the risk of death in the setting of coronary artery bypass (OR 0.74 [0.58-0.94]; P = .01). The number needed to treat was 100. CONCLUSION: Our data ruled out the hypothesis of any benefit of adding pexelizumab on top of currently available therapies for ST elevation myocardial infarction. However, pexelizumab reduces the risk of death in patients undergoing coronary artery bypass grafting.

Left main coronary artery 'embolectomy' using a novel, straightforward technique.

A 60-year-old man experienced catastrophic haemodynamic decompensation 3 days following coronary artery bypass grafting (CABG). Aspiration thrombectomy to remove a left main coronary artery saddle embolus resulted in immediate haemodynamic improvement with no requirement for angioplasty or repeat bypass grafting. Coronary thromboembolism should be considered in the differential diagnosis of haemodynamic collapse post CABG. Urgent coronary angiography and aspiration thrombectomy may result in significant improvement for this condition.

Vessel wall apoptosis and atherosclerotic plaque instability.

Atherosclerotic cardiovascular disease remains the leading cause of death in the industrialized world. Most cardiovascular deaths result from acute coronary syndromes, including unstable angina pectoris and acute myocardial infarction. Coronary syndromes often arise from acute coronary thrombosis, itself commonly a result of disruption or rupture of the fibrous cap of a lipid-laden atherosclerotic plaque. Despite this huge clinical burden of atherosclerotic plaque instability, our understanding of the molecular mechanisms mediating atherosclerotic plaque disruption and rupture, at a cellular level, remains limited. Placed in a clinical context, this review discusses our current understanding of the molecular basis for atherosclerotic plaque instability, with particular emphasis on the process of apoptosis-or programmed cell death-seen increasingly as playing a key role in a number of cell types within the vessel wall.