HSP25 Vaccination Attenuates Atherogenesis via Upregulation of LDLR Expression, Lowering of PCSK9 Levels and Curbing of Inflammation.

[Figure: see text].

Unlike estrogens that increase PCSK9 levels post-menopause HSP27 vaccination lowers cholesterol levels and atherogenesis due to divergent effects on PCSK9 and LDLR.

AIMS: The estrogen-inducible protein Heat Shock Protein 27 (HSP27) as well as anti-HSP27 antibodies are elevated in healthy subjects compared to cardiovascular disease patients. Vaccination of ApoE-/- mice with recombinant HSP25 (rHSP25, the murine ortholog), boosts anti- HSP25 levels and attenuates atherogenesis. As estrogens promote HSP27 synthesis, cellular release and blood levels, we hypothesize that menopause will result in loss of HSP27 atheroprotection. Hence, the rationale for this study is to compare the efficacy of rHSP25 vaccination vs. estradiol (E2) therapy for the prevention of post-menopausal atherogenesis. METHODS AND RESULTS: ApoE-/- mice subjected to ovariectomy (OVX) showed a 65 % increase atherosclerotic burden compared to sham mice after 5 weeks of a high fat diet. Relative to vaccination with rC1, a truncated HSP27 control peptide, atherogenesis was reduced by 5-weekly rHSP25 vaccinations (-43 %), a subcutaneous E2 slow release pellet (-52 %) or a combination thereof (-82 %). Plasma cholesterol levels declined in parallel with the reductions in atherogenesis, but relative to rC1/OVX mice plasma PCSK9 levels were 52 % higher in E2/OVX and 41 % lower in rHSP25/OVX mice (p < 0.0001 for both). Hepatic LDLR mRNA levels did not change with E2 treatment but increased markedly with rHSP25 vaccination. Conversely, hepatic PCSK9 mRNA increased 148 % with E2 treatment vs. rC1/OVX but did not change with rHSP25 vaccination. In human HepG2 hepatocytes E2 increased PCSK9 promoter activity 303 %, while the combination of [rHSP27 + PAb] decreased PCSK9 promoter activity by 64 %. CONCLUSION: The reduction in post-OVX atherogenesis and cholesterol levels with rHSP25 vaccination is associated with increased LDLR but not PCSK9 expression. Surprisingly, E2 therapy attenuates atherogenesis and cholesterol levels post-OVX without altering LDLR but increases PCSK9 expression and promoter activity. This is the first documentation of increased PCSK9 expression with E2 therapy and raises questions about balancing physiological estrogenic / PCSK9 homeostasis and targeting PCSK9 in women - are there effects beyond cholesterol?

4-Phenylbutyrate protects against atherosclerotic lesion growth by increasing the expression of HSP25 in macrophages and in the circulation of Apoe-/- mice.

Endoplasmic reticulum stress plays an important role in cardiovascular disease (CVD) and atherosclerosis. We aimed to assess the ability of 4-phenylbutyrate (4-PBA), a small chemical chaperone administered via drinking water, to reduce atherosclerotic lesion size in chow-fed apolipoprotein (Apo) e-/- mice and to identify mechanisms that contribute to its antiatherogenic effect. Chow-fed 17-wk-old female Apoe-/- mice treated with 4-PBA-supplemented drinking water for 5 wk exhibited smaller lesions as well as increased plasma levels of heat shock protein (HSP) 25, the mouse homolog of human HSP27, compared with controls. In addition, 4-PBA inhibited cell death and increased HSP27 expression as measured by real-time PCR and immunoblotting, as well as induced nuclear localization of its transcription factor, heat shock factor 1, in human monocyte/macrophage (THP-1) cells. Furthermore, HSP27 small interfering RNA diminished the protective effect of 4-PBA on THP-1 macrophage attachment and differentiation. In summary, drinking water containing 4-PBA attenuated early lesion growth in Apoe-/- mice fed a chow diet and increased expression of HSP25 and HSP27 in macrophages and HSP25 in the circulation of Apoe-/- mice. Given that increased expression of HSP27 is inversely correlated with CVD risk, our findings suggest that 4-PBA protects against the early stages of atherogenesis in part by enhancing HSP27 levels, leading to inhibition of both macrophage cell death and monocyte-macrophage differentiation.-Lynn, E. G., Lhoták, S., Lebeau, P., Byun, J. H., Chen, J., Platko, K., Shi, C., O'Brien, E. R., Austin, R. C. 4-Phenylbutyrate protects against atherosclerotic lesion growth by increasing the expression of HSP25 in macrophages and in the circulation of Apoe-/- mice.

Recombinant heat shock protein 27 (HSP27/HSPB1) protects against cadmium-induced oxidative stress and toxicity in human cervical cancer cells.

Cadmium (Cd) is a carcinogen with several well-described toxicological effects in humans, but its molecular mechanisms are still not fully understood. Overexpression of heat shock protein 27 (HSP27/HSPB1)-a multifunctional protein chaperone-has been shown to protect cells from oxidative damage and apoptosis triggered by Cd exposure. The aims of this work were to investigate the potential use of extracellular recombinant HSP27 to prevent/counteract Cd-induced cellular toxicity and to evaluate if peroxynitrite was involved in the development of Cd-induced toxicity. Here, we report that the harmful effects of Cd correlated with changes in oxidative stress markers: upregulation of reactive oxygen species, reduction in nitric oxide (NO) bioavailability, increment in lipid peroxidation, peroxynitrite (PN), and protein nitration; intracellular HSP27 was reduced. Treatments with Cd (100 µM) for 24 h or with the peroxynitrite donor, SIN-1, decreased HSP27 levels (~50%), suggesting that PN formation is responsible for the reduction of HSP27. Pre-treatments of the cells either with Nω-nitro-L-arginine methyl ester hydrochloride (L-NAME) (a pharmacological inhibitor of NO synthase) or with recombinant HSP27 (rHSP27) attenuated the disruption of the cellular metabolism induced by Cd, increasing in a 55 and 52%, respectively, the cell viability measured by CCK-8. Cd induced necrotic cell death pathways, although apoptosis was also activated; pre-treatment with L-NAME or rHSP27 mitigated cell death. Our findings show for the first time a direct relationship between Cd-induced toxicity and PN production and a role for rHSP27 as a potential therapeutic agent that may counteract Cd toxicity.

Heat shock protein 27-derived atheroprotection involves reverse cholesterol transport that is dependent on GM-CSF to maintain ABCA1 and ABCG1 expression in ApoE-/- mice.

Recently, we demonstrated that heat shock protein (HSP)-27 is protective against the development of experimental atherosclerosis, reducing plaque cholesterol content by more than 30%. Moreover, elevated HSP-27 levels are predictive of relative freedom from clinical cardiovascular events. HSP-27 signaling occurs via the activation of NF-κB, which induces a marked up-regulation in expression of granulocyte-monocyte colony-stimulating factor (GM-CSF), a cytokine that is known to alter ABC transporters involved in reverse cholesterol transport (RCT). Therefore, we hypothesized that HSP-27-derived GM-CSF has a potent role in impeding plaque formation by promoting macrophage RCT and sought to better characterize this pathway. Treatment of THP-1 cells, RAW-Blue cells, and primary macrophages with recombinant HSP-27 resulted in NF-κB activation via TLR-4 and was inhibited by various pharmacologic blockers of this pathway. Moreover, HSP-27-induced upregulation of GM-CSF expression was dependent on TLR-4 signaling. Recombinant (r)HSP-27 treatment of ApoE-/- female (but not male) mice for 4 wk yielded reductions in plaque area and cholesterol clefts of 33 and 47%, respectively, with no effect on GM-CSF-/-ApoE-/- mice. With 12 wk of rHSP-27 treatment, both female and male mice showed reductions in plaque burden (55 and 42%, respectively) and a 60% reduction in necrotic core area but no treatment effect in GM-CSF-/-ApoE-/- mice. In vitro functional studies revealed that HSP-27 enhanced the expression of ABCA1 and ABCG1, as well as facilitated cholesterol efflux in vitro by ∼10%. These novel findings establish a paradigm for HSP-27-mediated RCT and set the stage for the development of HSP-27 atheroprotective therapeutics.-Pulakazhi Venu, V. K., Adijiang, A., Seibert, T., Chen, Y.-X., Shi, C., Batulan, Z., O'Brien, E. R. Heat shock protein 27-derived atheroprotection involves reverse cholesterol transport that is dependent on GM-CSF to maintain ABCA1 and ABCG1 expression in ApoE-/- mice.

Impact of Center Experience on Patient Radiation Exposure During Transradial Coronary Angiography and Percutaneous Intervention: A Patient-Level, International, Collaborative, Multi-Center Analysis.

BACKGROUND: The adoption of the transradial (TR) approach over the traditional transfemoral (TF) approach has been hampered by concerns of increased radiation exposure-a subject of considerable debate within the field. We performed a patient-level, multi-center analysis to definitively address the impact of TR access on radiation exposure. METHODS AND RESULTS: Overall, 10 centers were included from 6 countries-Canada (2 centers), United Kingdom (2), Germany (2), Sweden (2), Hungary (1), and The Netherlands (1). We compared the radiation exposure of TR versus TF access using measured dose-area product (DAP). To account for local variations in equipment and exposure, standardized TR:TF DAP ratios were constructed per center with procedures separated by coronary angiography (CA) and percutaneous coronary intervention (PCI). Among 57 326 procedures, we demonstrated increased radiation exposure with the TR versus TF approach, particularly in the CA cohort across all centers (weighted-average ratios: CA, 1.15; PCI, 1.05). However, this was mitigated by increasing TR experience in the PCI cohort across all centers (r=-0.8; P=0.005). Over time, as a center transitioned to increasing TR experience (r=0.9; P=0.001), a concomitant decrease in radiation exposure occurred (r=-0.8; P=0.006). Ultimately, when a center's balance of TR to TF procedures approaches 50%, the resultant radiation exposure was equivalent. CONCLUSIONS: The TR approach is associated with a modest increase in patient radiation exposure. However, this increase is eliminated when the TR and TF approaches are used with equal frequency-a guiding principle for centers adopting the TR approach.

Clinical outcomes among patients with extreme obesity undergoing elective coronary revascularization: Evaluation of major complications in contemporary practice.

BACKGROUND/OBJECTIVES: Individuals with extreme obesity (EO), defined by a body mass index (BMI) ≥ 40 kg/m(2), constitute an increasingly prevalent population at higher risk of procedural complications. The implications of increasing weight burdens among this subset of patients in the setting of elective coronary revascularization have yet to be adequately studied. METHODS: We sought to define major complications in this group at one year following contemporary revascularization strategies by retrospectively analysing a cohort of consecutive EO patients undergoing elective percutaneous coronary intervention (PCI) or coronary artery bypass surgery (CABG). The primary endpoint was a composite of peri- and post-procedural complications. Secondary endpoints included a cardiovascular composite and target vessel revascularization (TVR). RESULTS: Adjusted event-free survival curves for the primary endpoint among 133 patients differed significantly with higher BMI (>43.2 kg/m(2)) associated with greater risk (p=0.02). The primary endpoint occurred more frequently with CABG compared to PCI (24.2% vs. 5.0%, p < 0.01), which remained significant after adjusting for differences in baseline variables. Rates of the cardiovascular composite and TVR were comparable. CONCLUSIONS: Increasing BMI was associated with greater risk for major complications among EO patients undergoing elective coronary revascularization. PCI was associated with fewer complications; however, both revascularization strategies demonstrated equivalent rates of death, MI, and/or stroke. Larger studies may permit a better understanding of the associations between increasing BMI and specific outcomes and to evaluate the role for pre-procedural weight loss in this select population.

The effects of knockdown of rho-associated kinase 1 and zipper-interacting protein kinase on gene expression and function in cultured human arterial smooth muscle cells.

Rho-associated kinase (ROCK) and zipper-interacting protein kinase (ZIPK) have been implicated in diverse physiological functions. ROCK1 phosphorylates and activates ZIPK suggesting that at least some of these physiological functions may require both enzymes. To test the hypothesis that sequential activation of ROCK1 and ZIPK is commonly involved in regulatory pathways, we utilized siRNA to knock down ROCK1 and ZIPK in cultured human arterial smooth muscle cells (SMC). Microarray analysis using a whole-transcript expression chip identified changes in gene expression induced by ROCK1 and ZIPK knockdown. ROCK1 knockdown affected the expression of 553 genes, while ZIPK knockdown affected the expression of 390 genes. A high incidence of regulation of transcription regulator genes was observed in both knockdowns. Other affected groups included transporters, kinases, peptidases, transmembrane and G protein-coupled receptors, growth factors, phosphatases and ion channels. Only 76 differentially expressed genes were common to ROCK1 and ZIPK knockdown. Ingenuity Pathway Analysis identified five pathways shared between the two knockdowns. We focused on cytokine signaling pathways since ROCK1 knockdown up-regulated 5 and down-regulated 4 cytokine genes, in contrast to ZIPK knockdown, which affected the expression of only two cytokine genes (both down-regulated). IL-6 gene expression and secretion of IL-6 protein were up-regulated by ROCK1 knockdown, whereas ZIPK knockdown reduced IL-6 mRNA expression and IL-6 protein secretion and increased ROCK1 protein expression, suggesting that ROCK1 may inhibit IL-6 secretion. IL-1ß mRNA and protein levels were increased in response to ROCK1 knockdown. Differences in the effects of ROCK1 and ZIPK knockdown on cell cycle regulatory genes suggested that ROCK1 and ZIPK regulate the cell cycle by different mechanisms. ROCK1, but not ZIPK knockdown reduced the viability and inhibited proliferation of vascular SMC. We conclude that ROCK1 and ZIPK have diverse, but predominantly distinct regulatory functions in vascular SMC and that ROCK1-mediated activation of ZIPK is not involved in most of these functions.

Role of mutation and pharmacologic block of human KCNH2 in vasculogenesis and fetal mortality: partial rescue by transforming growth factor-ß.

BACKGROUND: N629D KCNH2 is a human missense long-QT2 mutation. Previously, we reported that the N629D/N629D mutation embryos disrupted cardiac looping, right ventricle development, and ablated IKr activity at E9.5. The present study evaluates the role of KCNH2 in vasculogenesis. METHODS AND RESULTS: N629D/N629D yolk sac vessels and aorta consist of sinusoids without normal arborization. Isolated E9.5 +/+ first branchial arches showed normal outgrowth of mouse ERG-positive/α-smooth muscle actin coimmunolocalized cells; however, outgrowth was grossly reduced in N629D/N629D. N629D/N629D aortas showed fewer α-smooth muscle actin positive cells that were not coimmunolocalized with mouse ERG cells. Transforming growth factor-ß treatment of isolated N629D/N629D embryoid bodies partially rescued this phenotype. Cultured N629D/N629D embryos recapitulate the same cardiovascular phenotypes as seen in vivo. Transforming growth factor-ß treatment significantly rescued these embryonic phenotypes. Both in vivo and in vitro, dofetilide treatment, over a narrow window of time, entirely recapitulated the N629D/N629D fetal phenotypes. Exogenous transforming growth factor-ß treatment also rescued the dofetilide-induced phenotype toward normal. CONCLUSIONS: Loss of function of KCNH2 mutations results in defects in cardiogenesis and vasculogenesis. Because many medications inadvertently block the KCNH2 potassium current, these novel findings seem to have clinical relevance.

Granulocyte colony-stimulating factor therapy for stem cell mobilization following anterior wall myocardial infarction: the CAPITAL STEM MI randomized trial.

BACKGROUND: Small studies have yielded divergent results for administration of granulocyte colony-stimulating factor (G-CSF) after acute myocardial infarction. Adequately powered studies involving patients with at least moderate left ventricular dysfunction are lacking. METHODS: Patients with left ventricular ejection fraction less than 45% after anterior-wall myocardial infarction were treated with G-CSF (10 µg/kg daily for 4 days) or placebo. After initial randomization of 86 patients, 41 in the placebo group and 39 in the G-CSF group completed 6-month follow-up and underwent measurement of left ventricular ejection fraction by radionuclide angiography. RESULTS: Baseline and 6-week mean ejection fraction was similar for the G-CSF and placebo groups: 34.8% (95% confidence interval [CI] 32.6%-37.0%) v. 36.4% (95% CI 33.5%-39.2%) at baseline and 39.8% (95% CI 36.2%-43.4%) v. 43.1% (95% CI 39.2%-47.0%) at 6 weeks. However, G-CSF therapy was associated with a lower ejection fraction at 6 months relative to placebo (40.8% [95% CI 37.4%-44.2%] v. 46.0% [95% CI 42.7%-44.3%]). Both groups had improved left ventricular function, but change in left ventricular ejection fraction was lower in patients treated with G-CSF than in those who received placebo (5.7 [95% CI 3.4-8.1] percentage points v. 9.2 [95% CI 6.3-12.1] percentage points). One or more of a composite of several major adverse cardiac events occurred in 8 patients (19%) within each group, with similar rates of target-vessel revascularization. INTERPRETATION: In patients with moderate left ventricular dysfunction following anterior-wall infarction, G-CSF therapy was associated with a lower 6-month left ventricular ejection fraction but no increased risk of major adverse cardiac events. Future studies of G-CSF in patients with left ventricular dysfunction should be monitored closely for safety. TRIAL REGISTRATION: ClinicalTrials.gov, no. NCT00394498.

Heat shock protein 27 attenuates neointima formation and accelerates reendothelialization after arterial injury and stent implantation: importance of vascular endothelial growth factor up-regulation.

Elevated serum heat shock protein 27 (HSP27) levels are atheroprotective; however, the role of HSP27 after arterial injury is unknown. Human endothelial progenitor cells (EPCs) were treated with recombinant (r)HSP27 (50 µg/ml) or its inactive C1 terminus, and gene expression was characterized before functional studies were performed in vitro and in vivo. Vascular endothelial growth factor (VEGF) was markedly up-regulated by rHSP27 (10- and 6-fold increases in mRNA and secretion, respectively). Pretreatment of EPCs with rHSP27 resulted in a 60% reduction in reendothelialization (RE) time in a scratch assay, an effect that was blocked with VEGF-neutralizing antibodies. Mice overexpressing HSP27 demonstrated more robust mobilization of EPCs at the time of arterial injury, as well as a 67% increase in RE and a 45% reduction in neointima (NI) formation at 28 d. Implantation of rHSP27-eluting stents in rabbit carotid arteries resulted in a marked improvement in RE at 7 and 28 d and transient attenuation of NI formation by 42% at 7 d. Hence, extracellular HSP27 up-regulated VEGF and improved EPC migration in vitro. Augmented systemic or local levels of HSP27 markedly improved RE after vascular injury, an effect that is of particular relevance to the safety profile of vascular stents.

Heat shock protein-27 attenuates foam cell formation and atherogenesis by down-regulating scavenger receptor-A expression via NF-κB signaling.

Previously, we showed an inverse correlation between HSP27 serum levels and experimental atherogenesis in ApoE(-/-) mice that over-express HSP27 and speculated that the apparent binding of HSP27 to scavenger receptor-A (SR-A) was of mechanistic importance in attenuating foam cell formation. However, the nature and importance of the interplay between HSP27 and SR-A in atheroprotection remained unclear. Treatment of THP-1 macrophages with recombinant HSP27 (rHSP27) inhibited acLDL binding (-34%; p<0.005) and uptake (-38%, p<0.05). rHSP27 reduced SR-A mRNA (-39%, p=0.02), total protein (-56%, p=0.01) and cell surface (-53%, p<0.001) expression. The reduction in SR-A expression by rHSP27 was associated with a 4-fold increase in nuclear factor-kappa B (NF-κB) signaling (p<0.001 versus control), while an inhibitor of NF-κB signaling, BAY11-7082, attenuated the negative effects of rHSP27 on both SR-A expression and lipid uptake. To determine if SR-A is required for HSP27 mediated atheroprotection in vivo, ApoE(-/-) and ApoE(-/-) SR-A(-/-) mice fed with a high fat diet were treated for 3weeks with rHSP25. Compared to controls, rHSP25 therapy reduced aortic en face and aortic sinus atherosclerotic lesion size in ApoE(-/-) mice by 39% and 36% (p<0.05), respectively, but not in ApoE(-/-)SR-A(-/-) mice. In conclusion, rHSP27 diminishes SR-A expression, resulting in attenuated foam cell formation in vitro. Regulation of SR-A by HSP27 may involve the participation of NF-κB signaling. Lastly, SR-A is required for HSP27-mediated atheroprotection in vivo.

Chronic over-expression of heat shock protein 27 attenuates atherogenesis and enhances plaque remodeling: a combined histological and mechanical assessment of aortic lesions.

AIMS: Expression of Heat Shock Protein-27 (HSP27) is reduced in human coronary atherosclerosis. Over-expression of HSP27 is protective against the early formation of lesions in atherosclerosis-prone apoE(-/-) mice (apoE(-/-)HSP27(o/e)) - however, only in females. We now seek to determine if chronic HSP27 over-expression is protective in a model of advanced atherosclerosis in both male and female apoE(-/-) mice. METHODS AND RESULTS: After 12 weeks on a high fat diet, serum HSP27 levels rose more than 16-fold in male and female apoE(-/-)HSP27(o/e) mice, although females had higher levels than males. Relative to apoE(-/-) mice, female apoE(-/-)HSP27(o/e) mice showed reductions in aortic lesion area of 35% for en face and 30% for cross-sectional sinus tissue sections - with the same parameters reduced by 21% and 24% in male cohorts; respectively. Aortic plaques from apoE(-/-)HSP27(o/e) mice showed almost 50% reductions in the area occupied by cholesterol clefts and free cholesterol, with fewer macrophages and reduced apoptosis but greater intimal smooth muscle cell and collagen content. The analysis of the aortic mechanical properties showed increased vessel stiffness in apoE(-/-)HSP27(o/e) mice (41% in female, 34% in male) compare to apoE(-/-) counterparts. CONCLUSIONS: Chronic over-expression of HSP27 is atheroprotective in both sexes and coincides with reductions in lesion cholesterol accumulation as well as favorable plaque remodeling. These data provide new clues as to how HSP27 may improve not only the composition of atherosclerotic lesions but potentially their stability and resilience to plaque rupture.

Neuroimmune guidance cue Semaphorin 3E is expressed in atherosclerotic plaques and regulates macrophage retention.

OBJECTIVE: The persistence of myeloid-derived cells in the artery wall is a characteristic of advanced atherosclerotic plaques. However, the mechanisms by which these cells are retained are poorly understood. Semaphorins, a class of neuronal guidance molecules, play a critical role in vascular patterning and development, and recent studies suggest that they may also have immunomodulatory functions. The present study evaluates the expression of Semaphorin 3E (Sema3E) in settings relevant to atherosclerosis and its contribution to macrophage accumulation in plaques. APPROACH AND RESULTS: Immunofluorescence staining of Sema3E, and its receptor PlexinD1, demonstrated their expression in macrophages of advanced atherosclerotic lesions of Apoe(-/-) mice. Notably, in 2 different mouse models of atherosclerosis regression, Sema3E mRNA was highly downregulated in plaque macrophages, coincident with a reduction in plaque macrophage content and an enrichment in markers of reparative M2 macrophages. In vitro, Sema3E mRNA was highly expressed in inflammatory M1 macrophages and in macrophages treated with physiological drivers of plaque progression and inflammation, such as oxidized low-density lipoprotein and hypoxia. To explore mechanistically how Sema3E affects macrophage behavior, we treated macrophages with recombinant protein in the presence/absence of chemokines, including CCL19, a chemokine implicated in the egress of macrophages from atherosclerotic plaques. Sema3E blocked actin polymerization and macrophage migration stimulated by the chemokines, suggesting that it may immobilize these cells in the plaque. CONCLUSIONS: Sema3E is upregulated in macrophages of advanced plaques, is dynamically regulated by multiple atherosclerosis-relevant factors, and acts as a negative regulator of macrophage migration, which may promote macrophage retention and chronic inflammation in vivo.

Percutaneous coronary intervention with or without on-site coronary artery bypass surgery: a systematic review and meta-analysis.

BACKGROUND: Current American Heart Association guidelines recommend against the performance of elective or primary percutaneous coronary intervention (PCI) without on-site surgical backup (i.e. a class III and IIb recommendation respectively). Despite this, numerous centers have already implemented PCI programs with no on-site surgery backup (NSOS). METHODS: To evaluate the necessity for on-site surgical backup (SOS) when performing PCI we performed a systematic review and meta-analysis. English-language articles published from 1966 through December 2010 were retrieved using keyword searches of Medline and Scopus, supplemented by letters to authors and reviews of all bibliographies. Article inclusion and data extraction was performed by two independent reviewers. We identified 18 articles published between 1992 and 2009 which contained reported events on 1,150,200 patients. RESULTS: The combined odds ratio calculated using a random effects model for death with NSOS was 0.93 (95% CI, 0.80-1.09). In studies with data reported for primary PCI and elective PCI the OR for death was 0.91 (95% CI, 0.84-1.00) and 1.04 (95% CI, 0.67-1.63). A lack of effect of SOS was maintained when analysis was performed by study type or by either primary or elective PCI. No differences in rates of emergency coronary artery bypass grafting, post procedural myocardial infarction, target vessel revascularization, or cerebrovascular accidents were observed between SOS and NSOS centers. CONCLUSION: Both primary and elective PCI can safely be performed at NSOS centers without an increase in mortality or PCI related complications. AHA/ACC guidelines should reflect the lack of benefit conferred by on-site surgical backup. In establishing PCI programs, adequate operator/center volumes, patient selection, and geographic/population considerations should take precedence rather than the availability of on-site surgical backup during PCI.

Extracellular HSP27 acts as a signaling molecule to activate NF-κB in macrophages.

Heat shock protein 27 (HSP27) shows attenuated expression in human coronary arteries as the extent of atherosclerosis progresses. In mice, overexpression of HSP27 reduces atherogenesis, yet the precise mechanism(s) are incompletely understood. Inflammation plays a central role in atherogenesis, and of particular interest is the balance of pro- and anti-inflammatory factors produced by macrophages. As nuclear factor-kappa B (NF-κB) is a key immune signaling modulator in atherogenesis, and macrophages are known to secrete HSP27, we sought to determine if recombinant HSP27 (rHSP27) alters NF-κB signaling in macrophages. Treatment of THP-1 macrophages with rHSP27 resulted in the degradation of an inhibitor of NF-κB, IκBα, nuclear translocation of the NF-κB p65 subunit, and increased NF-κB transcriptional activity. Treatment of THP-1 macrophages with rHSP27 yielded increased expression of a variety of genes, including the pro-inflammatory factors, IL-1ß, and TNF-α. However, rHSP27 also increased the expression of the anti-inflammatory factors IL-10 and GM-CSF both at the mRNA and protein levels. Our study suggests that in macrophages, activation of NF-κB signaling by rHSP27 is associated with upregulated expression and secretion of key pro- and anti-inflammatory cytokines. Moreover, we surmise that it is the balance in expression of these mediators and antagonists of inflammation, and hence atherogenesis, that yields a favorable net effect of HSP27 on the vessel wall.

Transradial versus transfemoral artery approach for coronary angiography and percutaneous coronary intervention in the extremely obese.

OBJECTIVES: This study sought to evaluate the safety and efficacy of transradial versus transfemoral access for coronary angiography and percutaneous coronary intervention in patients with a body mass index ≥ 40 kg/m(2). BACKGROUND: Coronary angiography is most commonly performed via femoral artery access; however, the optimal approach in extremely obese (EO) patients remains unclear. METHODS: Between January 2007 and August 2010, a cohort of consecutive EO patients who underwent coronary angiography was identified in our center's registry of angiography and percutaneous coronary intervention procedures. Of 21,103 procedures, 564 (2.7%) were performed in unique EO patients: 203 (36%) via the transradial approach; and 361 (64%) via the transfemoral approach. RESULTS: The primary outcome, a combined endpoint of major bleeding, access site complications, and nonaccess site complications, occurred in 7.5% of the transfemoral group and 2.0% of the transradial group (odds ratio [OR]: 0.30, 95% confidence interval [CI]: 0.10 to 0.88, p = 0.029), an endpoint driven by reductions in major bleeding (3.3% vs. 0.0%, OR: 0.12, 95% CI: 0 to 0.71, p = 0.015), as well as access site injuries (4.7% vs. 0.0%, OR: 0.08, 95% CI: 0 to 0.48, p = 0.002). There were no differences in nonaccess site complications (1.7% vs. 2.0%, OR: 1.50, 95% CI: 0.41 to 5.55), but transradial access procedures were associated with an increase in procedure time and patient radiation dose (p < 0.05). CONCLUSIONS: Transfemoral access for coronary angiography and percutaneous coronary intervention was associated with more bleeding and access site complications when compared with a transradial approach. Important reductions in procedural associated morbidity may be possible with a transradial approach in EO patients.

Infective endocarditis presenting as ST-elevation myocardial infarction: an angiographic diagnosis.

While systemic embolic events occur with relative frequency in infective endocarditis (IE), coronary embolization remains an uncommon cause of ST elevation myocardial infarction. Herein we report a case of ventricular fibrillation and anterior ST elevation myocardial infarction occurring in a patient initially presenting with septic shock. Angiography proved diagnostic for IE of a native bicuspid aortic valve complicated by root abscess and left anterior descending artery occlusion. Histologic examination of the embolectomy specimen from the left anterior descending artery confirmed the presence of thrombus and bacteria. The present case highlights difficulties in identifying and managing patients with coronary embolism of vegetations from IE.