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Sirt (Sirtuin) 7, the most recently identified mammalian sirtuin, has been shown to contribute to appropriate wound healing processes after acute cardiovascular insult. However, its role in the development of cardiac remodeling after pressure overload is unclear. Cardiomyocyte-specific Sirt7-knockout and control mice were subjected to pressure overload induced by transverse aortic constriction. Cardiac hypertrophy and functions were then examined in these mice. Sirt7 protein expression was increased in myocardial tissue after pressure overload. Transverse aortic constriction-induced increases in heart weight/tibial length were significantly augmented in cardiomyocyte-specific Sirt7-knockout mice compared with those of control mice. Histological analysis showed that the cardiomyocyte cross-sectional area and fibrosis area were significantly larger in cardiomyocyte-specific Sirt7-deficient mice. Cardiac contractile functions were markedly decreased in cardiomyocyte-specific Sirt7-deficient mice. Mechanistically, we found that Sirt7 interacted directly with GATA4 and that the exacerbation of phenylephrine-induced cardiac hypertrophy by Sirt7 knockdown was decreased by GATA4 knockdown. Sirt7 deacetylated GATA4 in cardiomyocytes and regulated its transcriptional activity. Interestingly, we demonstrated that treatment with nicotinamide mononucleotide, a known key NAD + intermediate, ameliorated agonist-induced cardiac hypertrophies in a Sirt7-dependent manner in vitro. Sirt7 deficiency in cardiomyocytes promotes cardiomyocyte hypertrophy in response to pressure overload. Sirt7 exerts its antihypertrophic effect by interacting with and promoting deacetylation of GATA4.

Background: Sirt7 is a recently identified sirtuin and has important roles in various pathological conditions, including cancer progression and metabolic disorders. It has previously been reported that Sirt7 is a key molecule in acute myocardial wound healing and pressure overload-induced cardiac hypertrophy. In this study, the role of Sirt7 in neointimal formation after vascular injury is investigated. Methods and Results: Systemic (Sirt7−/−) and smooth muscle cell-specific Sirt7-deficient mice were subjected to femoral artery wire injury. Primary vascular smooth muscle cells (VSMCs) were isolated from the aorta of wild type (WT) and Sirt7−/−mice and their capacity for cell proliferation and migration was compared. Sirt7 expression was increased in vascular tissue at the sites of injury. Sirt7−/−mice demonstrated significant reduction in neointimal formation compared to WT mice. In vitro, Sirt7 deficiency attenuated the proliferation of serum-induced VSMCs. Serum stimulation-induced upregulation of cyclins and cyclin-dependent-kinase 2 (CDK2) was significantly attenuated in VSMCs of Sirt7−/−compared with WT mice. These changes were accompanied by enhanced expression of the microRNA 290-295 cluster, the translational negative regulator of CDK2, in VSMCs of Sirt7−/−mice. It was confirmed that smooth muscle cell-specific Sirt7-deficient mice showed significant reduction in neointima compared with control mice. Conclusions: Sirt7 deficiency attenuates neointimal formation after vascular injury. Given the predominant role in vascular neointimal formation, Sirt7 is a potentially suitable target for treatment of vascular diseases.

Visual Abstract, Highlights • Although the long-term effects of LCZ696 (sacubitril/valsartan) on cardiac dysfunction have been previously elucidated, the short-term effects on acute phase after acute MI is unknown. • Wild-type mice subjected to ligation of left anterior descending artery were randomly allocated to the vehicle, enalapril, or LCZ696 group 1 day after MI, resulting in the belief that LCZ696 could prevent cardiac rupture compared to the vehicle, whereas there was no significant difference in rate of cardiac rupture-free survival in the enalapril compared to the vehicle. • At 3 days after MI, the expression of interleukin-1β, interleukin-6, matrix MMP-9 mRNA and MMP-9 activity in the infarcted myocardium were significantly lower, plasma aldosterone levels were significantly lower, and cGMP levels were significantly higher, in the LCZ696 than the other groups. • In vitro assay using peritoneal macrophages found that the combination of valsartan plus LBQ657 (active form of sacubitril) reduced the LPS-induced gelatinolytic activity and MMP-9 mRNA expression of macrophages. • LCZ696 could suppress pro-inflammatory cytokines and extracellular matrix degradation in macrophages, and provides protection against post-MI cardiac rupture in mice., Summary LCZ696 (sacubitril/valsartan) can lower the risk of cardiovascular events in chronic heart failure. However, it is unclear whether LCZ696 can improve prognosis in patients with acute myocardial infarction (MI). The present study shows that LCZ696 can prevent cardiac rupture after MI, probably due to the suppression of pro-inflammatory cytokines, matrix metalloproteinase-9 activity and aldosterone production, and enhancement of natriuretic peptides in mice. These findings suggest the mechanistic insight of cardioprotective effects of LCZ696 against acute MI, resulting in the belief that LCZ696 might be useful clinically to improve survival after acute MI.

Wild-type transthyretin amyloidosis (ATTRwt) is often overlooked in elderly patients with left ventricular hypertrophy (LVH). Impaired atrial function, in addition to ventricular diastolic dysfunction, is one of the hallmarks of cardiac amyloidosis. Here, we assessed the hypothesis that atrial function evaluated by A-velocity in pulse Doppler echocardiography is useful to differentiate ATTRwt in elderly patients with LVH. We analyzed 133 consecutive patients who underwent tissue biopsy to rule out infiltrative cardiomyopathy in our institute. We excluded patients younger than 50 years, without LVH (LV thickness was less than 12 mm), with other types of cardiac amyloidosis and patients with chronic atrial fibrillation, and analyzed remaining 51 patients (ATTRwt: 16, non-ATTRwt: 35). ATTRwt patients were significantly older and had advanced heart failure compared with non-ATTRwt group. In echocardiography, E/A, E/e', and relative wall thickness was significantly higher in ATTRwt group than non-ATTRwt group. A-velocity was significantly decreased in ATTRWT group compared with non-ATTRwt group (40.8 ± 20.8 vs. 78.7 ± 28.2 cm/s, p = 0.0001). Multivariate logistic analysis using eight forced inclusion models identified trans-mitral Doppler A-wave velocity was more significant factor of cardiac amyloidosis in ATTRwt. In receiver operating characteristic (ROC) analysis, the area under the curve (AUC) for A-wave velocity in discrimination between ATTRwt and non-ATTRwt were 0.86 (CI 0.76-0.96, p

Background Progressive loss of skeletal muscle termed "sarcopenia" is an independent risk factor for mortality in patients with cardiovascular diseases. A simple screening test that can identify sarcopenia using three variables (age, grip strength and calf circumference) was recently developed. We evaluated the clinical utility of this screening test in patients with heart failure (HF). Methods and results HF patients were divided into the sarcopenia (n=82) and non-sarcopenia (n=37) groups based on the sarcopenia score. Circulating BNP and high-sensitive cardiac troponin T levels were significantly higher, and left ventricular ejection fraction was lower in the sarcopenia group than non-sarcopenia group. Kaplan–Meier curve showed that HF event-free survival rate was significantly lower in the sarcopenia group. Multivariate Cox proportional hazards analysis identified BNP (ln[BNP]) (hazard ratio [HR]: 1.58; 95% CI: 1.09–2.29, p=0.02), hs-CRP (ln[CRP]) (HR: 1.82; 95% CI: 1.23–2.68; p Conclusions The sarcopenia screening test can be used to predict future adverse events in patients with HF.

ObjectiveGrip strength is a well-characterised measure of weakness and of poor muscle performance, but there is a lack of consensus on its prognostic implications in terms of cardiac adverse events in patients with cardiac disorders.MethodsArticles were searched in PubMed, Cochrane Library, BioMed Central and EMBASE. The main inclusion criteria were patients with cardiac disorders (ischaemic heart disease, heart failure (HF), cardiomyopathies, valvulopathies, arrhythmias); evaluation of grip strength by handheld dynamometer; and relation between grip strength and outcomes. The endpoints of the study were cardiac death, all-cause mortality, hospital admission for HF, cerebrovascular accident (CVA) and myocardial infarction (MI). Data of interest were retrieved from the articles and after contact with authors, and then pooled in an individual patient meta-analysis. Univariate and multivariate logistic regression was performed to define predictors of outcomes.ResultsOverall, 23 480 patients were included from 7 studies. The mean age was 62.3±6.9 years and 70% were male. The mean follow-up was 2.82±1.7 years. After multivariate analysis grip strength (difference of 5 kg, 5× kg) emerged as an independent predictor of cardiac death (OR 0.84, 95% CI 0.79 to 0.89, pConclusionIn patients with cardiac disorders, grip strength predicted cardiac death, all-cause death and hospital admission for HF.Trial registration numberCRD42015025280.

Background— Sirt7, 1 of the 7 members of the mammalian sirtuin family, promotes oncogenic transformation. Tumor growth and metastasis require fibrotic and angiogenic responses. Here, we investigated the role of Sirt7 in cardiovascular tissue repair process. Methods and Results— In wild-type mice, Sirt7 expression increased in response to acute cardiovascular injury, including myocardial infarction and hind-limb ischemia, particularly at the active wound healing site. Compared with wild-type mice, homozygous Sirt7-deficient (Sirt7 −/− ) mice showed susceptibility to cardiac rupture after myocardial infarction, delayed blood flow recovery after hind-limb ischemia, and impaired wound healing after skin injury. Histological analysis showed reduced fibrosis, fibroblast differentiation, and inflammatory cell infiltration in the border zone of infarction in Sirt7 −/− mice. In vitro, Sirt7 −/− mouse–derived or Sirt7 siRNA–treated cardiac fibroblasts showed reduced transforming growth factor-β signal activation and low expression levels of fibrosis-related genes compared with wild-type mice–derived or control siRNA–treated cells. These changes were accompanied by reduction in transforming growth factor receptor I protein. Loss of Sirt7 activated autophagy in cardiac fibroblasts. Transforming growth factor-β receptor I downregulation induced by loss of Sirt7 was blocked by autophagy inhibitor, and interaction of Sirt7 with protein interacting with protein kinase-Cα was involved in this process. Conclusion— Sirt7 maintains transforming growth factor receptor I by modulating autophagy and is involved in the tissue repair process.

Fragmented QRS complex (fQRS) on 12-lead ECG is associated with myocardial fibrosis and ischemic scar. Interstitial fibrosis is one of the histological characteristics of left ventricular diastolic dysfunction (LVDD). However, the clinical importance of fQRS in patients with LVDD remains unclear. Here, we assessed the hypothesis that the presence of fQRS is associated with disease severity in patients with LVDD, and could be used as an additional parameter to differentiate patients with heart failure with preserved ejection fraction (HFpEF) from LVDD. We analyzed 12-lead ECG of 239 patients with LVDD. The patients were divided into two groups according to the presence or absence of fQRS; 88 patients had fQRS (fQRS group) and 151 patients did not have fQRS (non-fQRS group). The percentage of patients with heart failure in the fQRS group was significantly higher than that in the non-fQRS group. The levels of B-type natriuretic peptide (BNP) and high-sensitive troponin T were significantly higher in the fQRS group than those in the non-fQRS group. In univariate logistic regression analysis, fQRS was associated with the presence of heart failure in patients with LVDD. Multivariate logistic regression analysis identified fQRS and BNP as independent indicators for HFpEF. In conclusion, the presence of fQRS on the ECG could be used as an additional tool to differentiate HFpEF from LVDD.

Sarcopenia is frequently observed and associated with poor outcomes in patients with chronic kidney disease (CKD). A simple screening test for sarcopenia using age, grip strength, and calf circumference was recently developed. However, the clinical utility of this sarcopenia score in patients with CKD remains unclear.We calculated the sarcopenia score of 265 patients with CKD and followed the patients for cardiovascular events. The endpoint of this study was the composite of cardiovascular hospitalization and total mortality. We divided all participants into high (n = 166) and low (n = 99) sarcopenia score groups using a simple scoring system. Patients in the high sarcopenia score group showed significantly higher plasma B-type natriuretic peptide (BNP) levels than those in the low sarcopenia score group (median: 103.1, interquartile range: 46.3-310.0 vs. 46.7, 18.0-91.8 pg/mL; p 0.0001). The Kaplan-Meier curve revealed that the risk of cardiovascular events was significantly greater in the high sarcopenia score group (log-rank test: p 0.0001), even after potential confounding factors were corrected using propensity score matching. Multivariate Cox hazard analysis identified a high sarcopenia score (hazard ratio: 3.04, 95% confidence interval: 1.45-6.38, p = 0.003) as an independent predictor of the primary endpoints. Furthermore, the combination of a high sarcopenia score and high BNP level identified patients with a significantly higher probability of future events (p 0.0001).This study demonstrates that this simple screening score for sarcopenia could be a useful tool for estimating the future adverse event risk in patients with CKD.

Purpose In-stent restenosis has been decreasing through the introduction of drug-eluting stents (DES). On the other hand, adverse events such as very late stent thrombosis (VLST) and late catch-up phenomenon can occur especially with sirolimus-eluting stents (SES, first-generation DES) in long-term follow-up. However, the precise mechanisms underlying VLST have not been well investigated in vivo. Methods and results From 2004 to 2010, 2034 SES were implanted in 1656 patients and caused eight VLST (0.48% per patient) at Fukuoka Tokushukai Medical Center. Of these, serial intravascular ultrasound (IVUS) images (post-stent implantation and at the time of VLST onset) were obtained from three patients with VLST. Comparing them with eight control patients with SES implanted, the vascular reactivity of VLST patients was analyzed. Eight VLST happened 50 ± 15 months after stent implantation and three of the eight patients with VLST had not taken aspirin daily. There were no differences in minimum stent area, maximum external elastic membrane (EEM) area, and stent edge (distal and proximal) EEM area in post-procedural IVUS images. Compared with the control group patients, ΔEEM area (10.6 ± 3.4 mm2 vs. 1.7 ± 1.9 mm2, p = 0.01) and vessel expansion ratio (185.6 ± 40.3% vs. 112.0 ± 12.1%, p = 0.01) were significantly greater in the VLST group based on the greater peri-stent plaque expansion (262.1 ± 72.8% vs. 118.7 ± 21.2%, p = 0.01). Conclusion Our serial IVUS study showed that the vascular positive remodeling after SES implantation is one of the most probable morphological mechanisms for VLST development.

Supervised exercise is established intervention for patients with peripheral artery disease (PAD). In addition to aerobic exercise, it has been recognized that resistance exercise has beneficial effects for these patients. However, underling mechanism by which growing muscle improves blood flow is

Introduction: Aging is a well-established cardiovascular risk factor and associated with vascular dysfunction. Sirt7, one of the members of mammalian sirtuin family, is thought to be involved in age-related diseases. However, little is known about the relative contribution of Sirt7 in vascular dysfunction. Hypothesis: Sirt7 maintains vascular cell functions and its deficiency plays a critical role in vascular diseases. Methods: Sirt7 loss- and gain-of-function experiments were performed with human aortic smooth muscle cells (HAoSMCs) and human umbilical vein endothelial cells (HUVECs). In vivo, blood flow recovery was evaluated by hindlimb ischemia model in homozygous Sirt7 deficient (Sirt7-/-) and wild-type (WT) mice. Irradiated WT mice were intravenously received bone marrow (BM) cells from WT or Sirt7 -/- mouse to achieve BM transfer. Results: An RNAi-medicated Sirt7 knockdown resulted in a significant inhibition of HAoSMCs proliferation following serum or Platelet-derived growth factor BB (PDGF-BB) stimulation as determined by cell count, BrdU cell proliferation assay and MTS proliferation assay. Knockdown of endogenous Sirt7 also reduced cell migration as revealed by Boyden chamber migration assay. The Cyclin D1 and Cyclin dependent kinase 2 (CDK2) protein levels were significantly decreased in Sirt7 siRNA-treated HAoSMCs in response to serum or PDGF-BB stimulation. In endothelial cells, knockdown of Sirt7 attenuated tube formation, proliferation and migration. These changes were accompanied by reduced ERK activation and VCAM-1 mRNA and protein expression in Sirt7 siRNA-treated HUVECs. Conversely, overexpression of Sirt7 by adenovirus enhanced tube formation and cell proliferation. In vivo, blood flow recovery in response to hindlimb ischemia was significantly attenuated in Sirt7-/- mice compared with WT mice. There was no difference in blood flow recovery between WT mice transplanted with WT or Sirt7-/- BM cells suggesting that Sirt7 deficiency in vascular cells have a predominant effect on attenuated blood flow recovery in response to hindlimb ischemia. Conclusions: Sirt7 in blood vessel components have an important role in maintenance of vascular function. Sirt7 could be a promising therapeutic target for vascular diseases.

Background Pulmonary hypertension (PH) is a serious complication in patients with systemic scleroderma (SSc), therefore it is important to identify the factors that could predict the presence and progression of PH. Skin biopsy is performed in patients with SSc to examine the type and severity of the disease. MicroRNAs (miRNAs) are potential biomarkers for various cardiovascular diseases including PH. Methods and results We determined the skin miRNA expression profile in 15 SSc patients with (n = 6) and without PH (n = 9). A mixture of equal amounts of miRNAs from PH and non-PH patients were prepared and used for miRNA PCR array analysis. The analysis identified 591 upregulated miRNAs and 57 downregulated miRNAs in the PH group. Of these, only miRNAs with a Ct value of less than 35 were subjected to further analysis. When a 1.5-fold difference was considered meaningful, 32 miRNAs were upregulated and 14 miRNAs were downregulated in the PH group. Interestingly, 5 out of 14 downregulated miRNAs belonged to the let-7 family. The results were validated by quantitative real-time PCR with specific primer for each miRNA, which showed significant downregulation of five let-7 family members (let-7a, -7d, -7e, -7f, -7g) in 6 PH compared with 9 non-PH skin samples. The expression levels of let-7d and 7b correlated negatively with pulmonary arterial pressure measured by echocardiography. Conclusions The results suggest that skin miRNA is a potentially useful marker for the presence and severity of PH in patients with SSc.

Introduction: Reduced skeletal muscle function link to poor prognosis in patients with chronic heart failure (HF). Irisin is a newly identified muscle-derived protein found in human serum. The gene expression of irisin precursor fibronectin domain containing protein 5 in skeletal muscle is associated with exercise tolerance in HF patients. Hypothesis: Irisin could be a useful biomarker for disease severity and future adverse cardiovascular events in patients with HF with reduced ejection fraction (HFrEF). Methods and results: We measured serum irisin levels in 84 patients with HFrEF. HFrEF was defined as left ventricular ejection fraction≦50% and meet the Framingham criteria of HF. Serum irisin concentrations were measured by ELISA. The endpoint of this study was a composite of total mortality, cardiovascular hospitalization and coronary revascularization. Serum irisin levels were negatively correlated with serum high sensitive troponin T levels (r=-0.24, p=0.048). Right heart catheterization revealed that serum irisin levels had significant negative correlation with pulmonary capillary wedge pressure (r=-0.23, p=0.044). In receiver operating characteristic (ROC) analysis, cut-off values of irisin and BNP for prediction of one-year events were 55.548 ng/mL and 324.8 pg/mL, respectively. Kaplan Meier curve demonstrated that the event-free rate was decreased in the low irisin (≦cut-off value) group (log-rank test p=0.024). The combination of low irisin and high BNP (≧cut-off value) identified patients with a significantly higher probability of adverse events (p=0.008). Multivariate Cox hazard analysis identified low levels of irisin (≦cut-off value) (hazard ratio [HR]: 3.08; 95% confidence interval [CI]: 1.31-7.21, p=0.01) and ischemic etiology (HR: 3.32; 95% CI: 1.50-7.35, p=0.003) as independent predictors of mortality and cardiovascular events. ROC analysis revealed that irisin achieved an area under the curve (AUC) of 0.67 for one-year events (p=0.031), and that the AUC increased when irisin was added to BNP level (alone: 0.64, BNP+irisin: 0.74). Conclusions: Irisin could be a useful biomarker for evaluating disease severity and providing incremental prognostic information in patients with HFrEF.

Shock patients with restrictive cardiomyopathy due to cardiac amyloidosis are refractory to medical treatment. Here, we report a case of early initiation of intra-aortic balloon pumping (IABP) in a patient with cardiac amyloidosis who developed postoperative shock. Continuous hemodiafiltration was also applied to control circulating fluid volume. The mechanical treatments allowed reduction of the doses of catecholamine and diuretics and resulted in full recovery. It is reasonable to initiate IABP and hemofiltration dialysis during the early stages for the appropriate control of hemodynamics and fluid in shock patients with cardiac amyloidosis.

effect of CPAP on LV function in treated hypertensives with OSA. Methods: Fifty moderate to severe (apnea hypopnea index S 15) OSA patients (65.069.9 yrs.) were classified into two groups, based on the medication with and without C-PAP as follows; CPAP group (34 patients) and Non-CPAP group (16 patients). Longitudinal, radial and circumferential strain values (%) of LV elucidated by speckle tracking imaging and various conventional markers of echocardiography were compared before medication with follow-up period (2.260.6 yrs.). Results: Show the Table. Conclusion: CPAP improves the longitudinal systolic function significantly, and diastolic function such as E/e and left atrial dimension also decreased.

Introduction: Pulmonary hypertension (PH) is a serious complication in patients with systemic scleroderma (SSc), therefore it is important to identify the factors that could predict the presence an...

Introduction: MicroRNAs (miRNAs) have been shown to play an important role in various cardiovascular diseases. However, its roles in the pathogenesis of connective tissue disease-associated pulmonary hypertension (PH) are not clear. Hypothesis: In patents with systemic scleroderma (SSc), subcutaneous miRNAs expression profiles are different depending on the presence or absence of PH. Methods and Results: Data of 16 SSc patients who underwent subcutaneous tissue biopsy were available for retrospective analysis. To determine the changes in subcutaneous miRNAs expression profiles in SSc-associated PH, a mixture of equal amount of subcutaneous miRNAs from 6 PH or 6 non-PH were prepared. We performed miRNA PCR array analysis, and the miRNA expression was comprehensively compared between PH and non-PH group. We found that 591 miRNAs were upregulated, and 57 miRNAs were downregulated in PH group (Figure). Among them, only miRNAs which showed a Ct value less than 35 were considered for further analysis. When a 1.5-fold difference was considered meaningful, 32 miRNAs were upregulated, and 14 miRNAs were down regulated in PH group. Interestingly, 5 out of 14 downregulated miRNAs belong to let-7 family (let-7a, -7b, -7d, -7f, -7g). We validated the results by quantitative real-time PCR with specific primer for each miRNAs individually and found that 4 let-7 family members (let-7a, -7d, -7f, -7g) were significantly downregulated in 6 PH compared with those in 10 non-PH skin. The expression level of let-7d was negatively correlated with pulmonary arterial pressure measured by echocardiography. Conclusions: The expression level of let-7 family microRNAs in subcutaneous skin are lower in patients with SSc with PH than those without PH. Let-7 family microRNAs expression in subcutaneous skin negatively correlate with severity of PH in patients with SSc. Subcutaneous miRNA could be a useful marker to identify the presence and severity of PH in patients with SSc. ![][1] [1]: /embed/graphic-1.gif

Although spontaneous coronary artery dissection (SCAD) is one of the causes of acute coronary syndrome (ACS) or sudden cardiac death, its standard management, especially primary percutaneous coronary intervention (PCI) in ACS patients with ongoing ischemia, has not been established. We experienced three ACS patients with SCAD who were treated with a different strategy of primary PCI. Each PCI strategy led to different clinical and procedural results. We describe here such PCI strategies and results, and also discuss the literature regarding primary PCI strategies for SCAD-induced ACS patients with ongoing ischemia.

SummaryFibromuscular dysplasia (FMD) is one of the etiologies of renal artery stenosis (RAS) and secondary hypertension. Balloon angioplasty has emerged as the mainstay of treatment because patients with FMD usually show substantial clinical and anatomic response to renal angioplasty without stenting. We report a 21-year-old male case of FMD-induced RAS treated with intravascular ultrasound- and pressure gradient-guided renal angioplasty. Ultrasonic imaging of the stenotic renal artery clearly visualized adventitial fibrotic band surrounding the negative remodeled renal artery and the accompanying atherosclerotic plaque. The findings suggest that atherosclerotic change can occur in young patients with renal FMD that is basically considered to be nonatherosclerotic. Pressure gradient measurement is also useful in confirming hemodynamic improvement during angioplasty.