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Aims The Registry to Evaluate Early and Long‐Term PAH Disease Management (REVEAL) risk scores differentiate survivals in patients with pulmonary arterial hypertension (PAH). However, measurements of N‐terminal pro B‐type natriuretic peptide (NT‐proBNP) in the peripheral blood may not adequately reflect early‐stage decompensated heart failure (HF). Given that right heart catheterization (RHC) can facilitate measurements of intracardiac NT‐proBNP, in this study our aim was to evaluate the predictive role of right ventricular (RV) NT‐proBNP measurements in patients with PAH. Methods and results We prospectively collected intracardiac blood samples for NT‐proBNP measurements from patients diagnosed with World Health Organization Group I PAH during RHC. Clinical information including the aetiology of PAH (idiopathic, connective tissue disease, or congenital heart disease) and REVEAL scores were recorded. The primary endpoint was hospitalization for decompensated HF; median duration of follow‐up was 28 months. Among the 62 patients evaluated, 12 reached the designated endpoint. REVEAL risk scores were higher among patients hospitalized for HF. We detected no significant differences in plasma NT‐proBNP levels in peripheral circulation, in the right atrium, or in pulmonary arterial blood; however, significantly higher levels of NT‐proBNP were detected in the RV in patients diagnosed with PAH. RV NT‐proBNP was a sensitive predictor (cut‐off value 1500 pg/mL) of subsequent hospitalization for HF. Our findings indicate that RV NT‐proBNP levels add predictive value to REVEAL scores with respect to future hospitalization due to HF. Conclusions Right ventricular NT‐proBNP levels combined with REVEAL 2.0 could predict the development of subsequent HF in patients with PAH and may be a potential biomarker.

With the promising cardiovascular benefits in the STEP and SPRINT trials, the 2022 Taiwan's hypertension guidelines redefined the hypertension threshold as 130/80 mmHg and a universal blood-pressure target of130/80 mmHg. This study's objective was to examine the cost-effectiveness of the intensive blood-pressure target for hypertensive patients using estimated lifetime medical costs and quality-adjusted life years (QALY) from the Taiwan national payer's perspective. We developed a lifetime Markov model comparing the intensive and conservative blood-pressure targets. Incremental cost-effectiveness ratio (ICER) against the willing-to-pay thresholds at the one-time [US$34,000(NT$1,020,000)] and three-time [US$100,000(NT$3,000,000)] gross domestic product per capita were defined as very cost-effect and only cost-effective. The cost-effectiveness in different age stratifications and cardiovascular risks treated with a more intensive target (120 mmHg) were examined in the subgroup analyses. The new blood-pressure treatment target produced more lifetime medical costs [US$31,589(NT$947,670) versus US$26,788(NT$803,640)] and QALYs (12.54 versus 12.25), and the ICER was US$16,589(NT$497,670), which was 99.1% and 100% probability of a very cost-effective and cost-effective strategy. The ICERs in all age stratifications had more than a 90% probability of being very cost-effective, and ICERs decreased with age. More intensive control in patients with high cardiovascular risks produced a lower ICER [US$14,547(NT$436,410)]. In conclusion, Taiwan's new blood-pressure treatment target can prevent more cardiovascular events with acceptable costs per QALY below the willing-to-pay thresholds. The cost-effectiveness of intensive control is consistent across different ages and more pronounced with the increase in age and cardiovascular risk.

Coronary flow velocity (CFV) is reduced in pathologic cardiac hypertrophy. This functional reduction is linked to adverse cardiac remodeling, hypertension and fibrosis, and angiotensin II (AngII) is a key molecular player. Angiotensin receptor blockers (ARBs) are known to attenuate adverse cardiac remodeling and fibrosis following increased afterload, while the mechanism by which these drugs offer clinical benefits and regulate hemodynamics remains unknown. To establish a direct connection between coronary flow changes and angiotensin-induced hypertension, we used a Doppler echocardiographic method in two distinct disease models. First, we performed serial echocardiography to visualize coronary flow and assess heart function in patients newly diagnosed with hypertension and currently on ARBs or calcium channel blockers (CCBs). CFV improved significantly in the hypertensive patients after 12 weeks of ARB treatment but not in those treated with CCBs. Second, using murine models of pressure overload, including Ang II infusion and aortic banding, we mimicked the clinical conditions of Ang II- and mechanical stress-induced hypertension, respectively. Both Ang II infusion and aortic banding increased the end-systolic pressure-volume relationship and cardiac fibrosis, but interestingly, only Ang II infusion resulted in a significant reduction in CFV and corresponding activation of pressure-sensitive proteins, including connective tissue growth factor, hypoxia-inducible factor 1α and signal transducer and activator of transcription 3. These data support the existence of a molecular and functional link between AngII-induced hemodynamic remodeling and alterations in coronary vasculature, which, in part, can explain the clinical benefit of ARB treatment in hypertensive patients.

How renal function influences post-acute myocardial infarction (AMI) cardiac remodeling and outcomes remains unclear. This study evaluated the impact of levels of renal impairment on drug therapy, echocardiographic parameters, and outcomes in patients with AMI undergoing percutaneous coronary intervention (PCI). A total of 611 patients diagnosed with AMI underwent successful PCI, and two echocardiographic examinations were performed within 1 year after AMI. Patients were categorized according to Group 1: severely impaired estimated glomerular filtration rate (eGFR)

Dapagliflozin (DAPA), a sodium–glucose cotransporter 2 inhibitor, is approved for treatments of patients with diabetes. The DAPA-HF (Dapagliflozin and Prevention of Adverse Outcomes in Heart Failure) trial disclosed DAPA’s benefits in symptomatic heart failure, but the underlying mechanism remains largely unknown. In this longitudinal and prospective study, we investigated changes of left ventricular functions including speckle tracking in patients with diabetes who were free from symptomatic heart failure post–DAPA treatment. Using a rat model with streptozotocin-induced diabetes, we measured the effects of DAPA on myocardial function. In patients with diabetes, following 6 months of DAPA treatment, despite no significant changes in left ventricular ejection fraction, the diastolic function and longitudinal strain improved. Likewise, compared with control, the diabetic rat heart developed pronounced fibrosis and a decline in strain and overall hemodynamics, all of which were mitigated by DAPA treatment. In contrast, despite insulin exerting a glucose-lowering effect, it failed to improve myocardial function and fibrosis. In our in vitro study, under high glucose cardiomyocytes showed significant activations of apoptosis, reactive oxygen species, and endoplasmic reticulum (ER) stress–associated proteins, which were attenuated by the coincubation of DAPA. Mechanistically, DAPA suppressed ER stress, reduced myocardial fibrosis, and improved overall function. The results can lead to further improvement in management of left ventricular function in patients with diabetes.

This study aimed to investigate the cost-effectiveness of low-dose rivaroxaban plus aspirin versus aspirin alone for patients with stable cardiovascular diseases in the Taiwan setting. We constructed a Markov model to project the lifetime direct medical costs and quality-adjusted life-years of both therapies. Transitional probabilities were derived from the COMPASS trial, and the costs and utilities were obtained from the Taiwan National Health Insurance Database and published studies. One-way, scenario, subgroup, and probabilistic sensitivity analyses were performed to assess the uncertainty. Incremental cost-effectiveness ratio was presented as the outcome. The threshold of willingness-to-pay was set at US$76,368 (3 times the gross domestic product per capita of Taiwan). All analyses were operated by TreeAge 2019 and Microsoft Excel. The incremental cost-effectiveness ratios of rivaroxaban plus aspirin versus aspirin alone in the patients with stable cardiovascular diseases, coronary artery diseases, and peripheral artery diseases were US$83,459, US$69,852 and −US$13,823 per quality-adjusted life-year gained, respectively. The probabilistic sensitivity analyses showed that the probabilities of cost-effectiveness for the regimen with rivaroxaban among those with cardiovascular diseases and coronary artery diseases were 44.1% and 65.3% at US$76,368. Low-dose rivaroxaban plus aspirin is less likely to be a cost-effective alternative to aspirin in secondary prevention for the patients with stable cardiovascular diseases; however, among these patients, the regimen may have pharmacoeconomic incentives for the group merely having chronic coronary artery diseases from the Taiwan national payer’s perspective. The pharmacoeconomic incentives are influenced by the drug price, event treatment fees, and willingness-to-pay threshold.

Anthracycline anticancer drugs such as epirubicin and doxorubicin may induce myocardial dysfunction, leading to poor prognosis. Early detection of minor left ventricular (LV) myocardial dysfunction is important for the prevention of anthracylcine-induced cardiotoxicity. Using layer-specific speckle tracking echocardiography (STE), we investigated the progressive distribution of myocardial dysfunction in both breast cancer patients and an animal toxicity model.Patients with preserved LV ejection fraction (LVEF) preparing for epirubicin chemotherapy (N = 125) were prospectively enrolled. Layer-specific STE, including LV longitudinal and circumferential strains on subepicardium and subendocardium, were evaluated at baseline and after the first cycle, third cycle and six months of epirubicin therapy. A decline of LVEF above 10% to55% at six months was defined as cardiotoxicity. These same strain measures were obtained in doxorubicin-treated rats and the distribution of myocardial fibrosis evaluated.In patients developing cardiotoxicity, LV longitudinal strain on subendocardium (LVLSendo) was significantly reduced after three cycles of therapy despite no significant changes in conventional LV systolic, diastolic parameters as well as LV circumferential strains at that moment. Compared to conventional echocardiographic parameters, LVLSendo was significantly predictive of cardiotoxicity. Declines in LVLSendo were also observed in doxorubicin-treated rats at an early stage. These reductions also predicted significant fibrosis in the subendocardial layer.LVLSendo is useful for the early detection of minor cardiac dysfunction during chemotherapy, thereby implicating endocardial involvement in the development of cardiotoxicity.

Aims There is a lack of studies that rigorously and systematically assess the economic burden of cardiovascular diseases (CVDs) related to the use of antiretroviral therapy (ART). We aimed to assess the association between adherence to ART and economic burden of CVDs in an HIV-infected population. Methods Taiwan's National Health Insurance Research Database 2000–2011 was utilized for analyzing 18,071 HIV-infected patients free of CVDs before HIV diagnosis. The level of adherence to ART was measured by the medication possession ratio (MPR). Generalized estimating equations analysis was applied to estimate the cost impact of a variety of CVDs. All costs were presented in 2018 US dollars. Results The incidence of CVDs ranged from 0.17/1000 person-years (cardiogenic shock) to 2.60/1000 person-years (ischemic heart diseases (IHDs)). The mean annual medical cost for a base-case patient without CVDs was US$3000. Having cerebrovascular diseases, myocardial infarction, heart failure, arrhythmia, and IHDs increased annual costs by 41%, 33%, 30%, 16%, and 14%, respectively. The cost impact of incident CVDs in years with high adherence to ART (MPR ≥ 0.8) was significantly lower than that in years with low adherence (MPR Conclusion The economic burden of incident CVDs in an HIV-infected population was compelling and varied by the extent of using ART. A reduced economic impact of CVDs was found in years when patients possessed a greater adherence to ART.

Left ventricular hypertrophy is an independent risk factor in diabetic patients. TGR5 is shown to express in hearts, but its functional role in diabetes-induced cardiac hypertrophy remained unclear. The current study investigated the role of TGR5 on high glucose-induced hypertrophy of H9C2 cells. After incubation with a high level of glucose, H9C2 cells showed hypertrophic responses. Activation of TGR5 by lithocholic acid (LCA) ameliorated cell hypertrophy and enhanced SERCA2a and phosphorylated phospholamban (PLN) expression in H9C2 cells. Triamterene inhibited these effects at an effective dose to block TGR5. However, LCA failed to modify the free radical elevation induced by high-glucose in the H9c2 cells. Moreover, PKA inhibitors, but not an Epac blocker, markedly improved hyperglycemia-induced hypertrophy and attenuated the increased SERCA2a expression by LCA; it also attenuated the phosphorylated PLN and SERCA2a protein expression levels in high glucose-treated H9C2 cells. In conclusion, TGR5 activation stimulated protein kinase A (PKA) to enhance PLN phosphorylation, which activated SERCA2a to remove Ca2+ from cytosol to sarcoplasmic reticulum in addition to the reduction of calcineurin/NFAT pathway signaling to ameliorate the hyperglycemia-induced cardiac hypertrophy shown in cardiomyocytes. TGR5 may service as a new target in the control of diabetic cardiomyopathy.

BackgroundMitral regurgitation (MR) is a major contributor for heart failure (HF) and atrial fibrillation. Despite the advancement of MR surgeries, an effective medical therapy to mitigate MR progression is lacking. Sodium glucose cotransporter 2 inhibitors, a new class of antidiabetic drugs, has shown measurable benefits in reduction of HF hospitalization and cardiovascular mortality but the mechanism is unclear. We hypothesized that dapagliflozin (DAPA), a sodium glucose cotransporter 2 inhibitor, can improve cardiac hemodynamics in MR‐induced HF.Methods and ResultsUsing a novel, mini‐invasive technique, we established a MR model in rats, in which MR induced left heart dilatation and functional decline. Half of the rats were randomized to be administered with DAPA at 10 mg/kg per day for 6 weeks. After evaluation of electrocardiography and echocardiography, hemodynamic studies were performed, followed by postmortem tissue analyses. Results showed that DAPA partially rescued MR‐induced impairment including partial restoration of left ventricular ejection fraction and end‐systolic pressure volume relationship. Despite no significant changes in electrocardiography at rest, rats treated with DAPA exhibited lower inducibility and decreased duration of pacing‐induced atrial fibrillation. DAPA also significantly attenuated cardiac fibrosis, cardiac expression of apoptosis, and endoplasmic reticulum stress‐associated proteins.ConclusionsDAPA was able to suppress cardiac fibrosis and endoplasmic reticulum stress and improve hemodynamics in an MR‐induced HF rat model. The demonstrated DAPA effect on the heart and its association with key molecular contributors in eliciting its cardio‐protective function, provides a plausible point of DAPA as a potential strategy for MR‐induced HF.

Despite no significant differences of growth differentiation factor-15 expressions in peripheral, right atrial, and right ventricular blood, in the pulmonary arterial blood, there was a significantly high level of growth differentiation factor-15 in Group I pulmonary arterial hypertension patients subsequently developing heart failure. During right heart catheterization, collecting pulmonary blood samples is suggested to measure growth differentiation factor-15.

Background: Cancer patients with diabetes have an increasing risk of Dox-induced cardiotoxicity. Despite previous studies reporting benefits of dapagliflozin on the cardiovascular system, it remains unknown whether dapagliflozin has a cardioprotective effect in cancer patients with diabetes receiving Dox therapy. The purpose of this study was to investigate the potential of dapagliflozin for preventing doxorubicin (Dox)-induced cardiotoxicity.Methods: Using Taiwan National Health Insurance Database, the incidence of heart failure of cancer patients with or without diabetes was investigated. Streptozotocin (STZ)-induced diabetic rats were pretreated with oral dapagliflozin (10 mg/kg/day) for 6 weeks followed by Dox (5 mg/kg/week) for 4 weeks via intraperitoneal injection. Sequential echocardiography was applied to assess cardiac function. For in vitro analysis, cardiomyocytes cultured in high glucose (30 mM) were treated with dapagliflozin at 10 M and subsequently exposed to Dox at 1 M. Apoptosis and endoplasmic reticulum (ER) stress-related protein expression were measured by immunohistochemistry and Western blotting.Results: Among the studied patients, those with diabetes had a higher risk of major adverse cardiovascular events including the development of heart failure. In diabetic rats, dapagliflozin reduced cardiac fibrosis and significantly improved cardiac function. Dapagliflozin effectively inhibited Dox-induced apoptosis and reactive oxygen species in cardiomyocytes under high glucose. Mechanistically, we showed that dapagliflozin decreased the cardiac expression of Bax and cleaved caspase 3 but increased Bcl-2. Dapagliflozin also significantly reduced ER stress-associated proteins including GRP78, PERK, eIF-2, ATF-4, and CHOP. Conclusions: Our study revealed for the first time that dapagliflozin mitigated Dox-induced cardiomyocyte apoptosis in diabetes via inhibiting ER stress. These results indicate that dapagliflozin could be useful for preventing cardiotoxicity in diabetic cancer patients receiving Dox treatment.

Heart failure (HF) with mid-range ejection fraction (HFmrEF) is defined as HF with a left ventricular (LV) ejection fraction (LVEF) of 41-49%. However, the change in LV function and the subsequent prognosis in these patients remain unclear. We aimed to investigate whether LV global longitudinal strain (LV GLS) could differentiate the changes in LVEF and predict the clinical outcomes in patients with HFmrEF.According to the changes in LVEF on follow-up echocardiography, 273 outpatients with HFmrEF were divided into 3 groups: HFwEF (HF with worse EF:40%), HFsEF (HF with similar EF: 40-49%), and HFrecEF (HF with recovered EF:50%). Further, the LV GLS at diagnosis was evaluated.The average follow-up duration was 31 months. Among patients with HFmrEF, the more impaired the LV GLS at baseline, the higher probability of HFwEF development. In comparison with patients with HFwEF and HFsEF, those with HFrecEF had a lower risk of hospitalization for HF. At a cut-off value of -11%, LV GLS differentiated the subsequent risk of cardiovascular death in patients with HFmrEF. In Cox regression, patients with LV GLS-11% had a high risk of cardiovascular death.In patients with HFmrEF, LV GLS is associated with LVEF changes and subsequent cardiovascular death. Patients with HFrecEF had a lower risk of hospitalization for HF.

ObjectiveVaricose veins (VVs) are common and although considered benign may cause morbidity. However, the association between VV severity and cardiovascular and mortality risks remains unknown. The aim of this study was to investigate the factors associated with overall mortality in patients with VV.MethodsA total of 4644 patients with newly diagnosed VV between 1999 and 2013 were identified from Taiwan’s National Health Insurance Database. VV severity was classified from grade 1 to 3 according to the presentation of ulcers or inflammation. Moreover, 9497, 2541 and 5722 age-matched, sex-matched and chronic cardiovascular risk factor-matched controls, as assessed based on propensity score, were separately selected for three grading VV groups. Enrolled patients were analysed using conditional Cox proportional hazards regression analysis to estimate risk of mortality and major adverse cardiovascular events (MACEs) in the VV and control groups.ResultsMost patients with VV were free from systemic disease. However, compared with matched controls, patients with VV showed a 1.37 times increased risk of mortality (95% CI 1.19 to 1.57; pConclusionsThis nationwide cohort study demonstrated that patients with VV are at a risk of cardiovascular events and mortality. Our findings suggest that presence of VV warrants close attention in terms of prognosis and treatment.

Cardiac hypertrophy is widely diagnosed in clinical cardiac disorders. The pathophysiology of hypertrophy is complex and multifactorial, a series of molecular and cellular changes are participated, such as activation of different signaling pathways, a switch of fetal gene program in the myocardium, and apoptosis. Some biomarkers have been applied to assess cardiac hypertrophy including atrial natriuretic peptides (ANP), brain/B-type natriuretic peptides (BNP), and α- or β- Myosin Heavy Chain (MHC) in addition to others. Recently, ubiquitin-protein ligase E3A (UBE3A) has been observed to increase in cardiac hypertrophy. Therefore, UBE3A as a new biomarker seems valuable in the clinic. The cardiac hypertrophy is induced in rat-derived heart cell line H9c2 cells by potassium bromate (KBrO3), high glucose (HG), or isoproterenol (Iso), respectively. As an oxidizing agent, KBrO3 increased cell size at concentrations less than 250 μM. Similarly, HG and Iso also induced cardiac hypertrophy in H9c2 cells. Interestingly, each kind of the cell models promoted the gene expression of the well-known biomarkers of cardiac hypertrophy including atrial natriuretic peptides (ANP) and brain/B-type natriuretic peptides (BNP). Additionally, UBE3A is also raised with the signals involved in cardiac hypertrophy such as calcineurin and nuclear factor of activated T-cells (NFAT) determined using Western blots. KBrO3 increased the protein levels of these signals and the specific inhibitor, such as cyclosporine A and tacrolimus, attenuated the signaling in H9c2 cells at concentrations sufficient to inhibit calcineurin in addition to the reduction of mRNA levels of UBE3A, similar to ANP or BNP. Moreover, HG or Iso also significantly increased protein levels of UBE3A in H9c2 cells. Taken together, we provided a new view that UBE3A is markedly raised in cardiac hypertrophy using various cell models, mainly through the activation of the calcineurin/NFAT signaling pathway in H9c2 cells. Therefore, UBE3A could be developed as a new biomarker in the diagnosis of cardiac hypertrophy. Keywords: Hypertrophic signals, Hyperglycemia, H9c2 cells, Isoproterenol, Potassium bromate

Objective Bone marrow fluid (BMF) consists of various components that establishes a microenvironment for cell differentiation and remodeling. MicroRNA-21 (miR-21) levels have recently emerged as novel biomarkers for different diseases. However, the conventional RNU6B (U6), used as the reference for intracellular miRNA, may not be appropriate for the normalization of circulating miRNAs. Methods We measured the levels of U6, spiked-in RNA, and miR-21 in the BMF of 13 healthy controls and 37 patients with hematological disorders to investigate the reliability of either U6 or spike-in RNA as an endogenous reference and also to study the correlation between miR-21, hematological disorders and mortality. Results Notably, the levels of U6 demonstrated a high variability in BMF of healthy controls and patients. In contrast, the levels of spiked-in RNA displayed a significantly higher stability in both cohorts. Compared with controls, the levels of miR-21 were significantly upregulated in BMF of patients with leukemia but not lymphoma. Also, using 21 as the cut-off value of miR-21, it differentiated the mortality of patients with hematologic disorders. Conclusions Collectively, using spiked-in RNA as a reference the upregulated miR-21 levels in BMF could be an indicator of the diagnosis of leukemia and a predictor of mortality.

Background: How sex and age influence post-myocardial infarction (post-MI) outcomes remains unclear. This study evaluated the influence of sex and age on drug therapy, echocardiographic parameters, and outcomes in post-MI patients undergoing percutaneous coronary intervention (PCI). Methods: We retrospectively enrolled 643 patients with first acute MI who underwent successful PCI and two echocardiographic examinations within 1 year after MI. Clinical characteristics and 4-year follow-up outcomes were compared between sexes and age groups. Primary endpoints were cardiovascular mortality and hospitalization for heart failure (HF). Results: Compared with males, female patients with MI, particularly older females, had more systemic diseases. Younger females received fewer guideline-directed therapies. Older patients presented with higher left ventricular volume and mass index but no significant differences in left ventricular ejection fraction. The Kaplan–Meier analysis revealed increased mortality in both younger and older females. Elderly patients, particularly older females, exhibited significantly higher post-MI HF incidence but no difference in recurrent MI, ventricular arrhythmia, or revascularization. Conclusions: In MI patients receiving PCI, outcome differences between sexes are age-dependent. Age influences outcome more heavily in females than in males. Females are likely to exhibit worse overall survival, and older females are at higher risk of post-MI HF. Keywords: MI, Age, Gender, Cardiac structure

Alirocumab can provide significant reductions in low-density lipoprotein cholesterol (LDL-C). However, data regarding its efficacy and safety in Asians are limited.A subgroup analysis of Taiwanese patients (n = 116) in a randomized trial evaluating the efficacy and safety of alirocumab in South Korea and Taiwan (ODYSSEY KT, clinicaltrials.gov Identifier: NCT02289963) was performed. Patients with hypercholesterolemia at high cardiovascular risk on maximally tolerated statin were randomized to alirocumab (75 mg every 2 weeks; with dose increased to 150 mg at Week 12 if LDL-C ≥ 70 mg/dL at Week 8) or placebo for 24 weeks. The primary efficacy endpoint was the percent change in LDL-C from baseline to Week 24. Safety was assessed for a total of 32 weeks.At Week 24, the percent change in calculated LDL-C in the alirocumab group (n = 57) was -51%, whereas that in the placebo group (n = 59) was 2.5%. Alirocumab significantly improved other lipid parameters, including non-high-density lipoprotein cholesterol, apolipoprotein B and A1, lipoprotein (a), high-density lipoprotein cholesterol, and total cholesterol. A significantly higher proportion of patients in the alirocumab group reached an LDL-C target below 70 mg/dL than those in the placebo group (81.3% vs 15.4%). The incidence of treatment-emergent adverse events was comparable between both groups.Alirocumab treatment provided a favorable effect on LDL-C levels and other lipid parameters, and was generally well-tolerated in patients from Taiwan. The results of current analysis were consistent with the overall ODYSSEY phase 3 program.

OBJECTIVE Atrial fibrillation (AF) is the most common cardiac complication of thyrotoxicosis and is strongly implicated in thromboembolic events. However, the incidence of stroke in thyrotoxic AF remains unclear. Herein, we aimed to investigate the risks of mortality and ischaemic stroke between patients with thyrotoxic AF and nonthyrotoxic AF. DESIGNS AND METHODS From Taiwan's National Health Insurance Research Database, 1868 patients with the concomitant diagnoses of AF and thyrotoxicosis identified between 2001 and 2010 were compared to 7472 patients with nonthyrotoxic AF using propensity score matching for age, sex and comorbidities. RESULTS There was no significant difference in either CHA2 DS2 -VASc score or anticoagulant usage between the groups. Alternatively, the thyrotoxic group contained more β-blocker/digoxin users, whereas the nonthyrotoxic group contained more statin users. Patients with thyrotoxic AF exhibited lower risks of all-cause mortality (HR: 0.66, CI: 0.59-0.73, P

Cryptotanshinone is an active principal ingredient isolated from Salvia miltiorrhiza (Danshen), a medicinal plant used in China to treat cardiac disorders. The objective of this study was to investigate the effect of cryptotanshinone on myocardial fibrosis in diabetic rats. In streptozotocin-induced type 1 diabetic model hyperglycemic rats (STZ-treated rats), fasting blood glucose levels and heart weight/body weight ratio were markedly increased but both were not modified by cryptotanshinone. Additionally, cardiac performance in catheterized STZ-treated rats was improved. The histological results from Masson staining showed that cryptotanshinone attenuated cardiac fibrosis in STZ-treated rats. Moreover, both the mRNA and protein levels of the signal transducer and activator of transcription 3 (STAT3), matrix metalloproteinase-9, and connective tissue growth factor were reduced by cryptotanshinone in high glucose-cultured cardiomyocytes, similar to the reductions observed in the hearts of STZ-treated rats. In conclusion, while STAT3 regulates matrix metalloproteinase-9 and connective tissue growth factor expression in diabetic rats with cardiac fibrosis, cryptotanshinone inhibited fibrosis to improve cardiac function by suppressing the STAT3 pathway. Cryptotanshinone is suitable as an alternative remedy for therapy of cardiac fibrosis. Copyright © 2017 John Wiley & Sons, Ltd.

Contains fulltext : 215333.pdf (Publisher’s version ) (Closed access) BACKGROUND: Patients with stable coronary artery disease and diabetes with previous percutaneous coronary intervention (PCI), particularly those with previous stenting, are at high risk of ischaemic events. These patients are generally treated with aspirin. In this trial, we aimed to investigate if these patients would benefit from treatment with aspirin plus ticagrelor. METHODS: The Effect of Ticagrelor on Health Outcomes in diabEtes Mellitus patients Intervention Study (THEMIS) was a phase 3 randomised, double-blinded, placebo-controlled trial, done in 1315 sites in 42 countries. Patients were eligible if 50 years or older, with type 2 diabetes, receiving anti-hyperglycaemic drugs for at least 6 months, with stable coronary artery disease, and one of three other mutually non-exclusive criteria: a history of previous PCI or of coronary artery bypass grafting, or documentation of angiographic stenosis of 50% or more in at least one coronary artery. Eligible patients were randomly assigned (1:1) to either ticagrelor or placebo, by use of an interactive voice-response or web-response system. The THEMIS-PCI trial comprised a prespecified subgroup of patients with previous PCI. The primary efficacy outcome was a composite of cardiovascular death, myocardial infarction, or stroke (measured in the intention-to-treat population). FINDINGS: Between Feb 17, 2014, and May 24, 2016, 11 154 patients (58% of the overall THEMIS trial) with a history of previous PCI were enrolled in the THEMIS-PCI trial. Median follow-up was 3.3 years (IQR 2.8-3.8). In the previous PCI group, fewer patients receiving ticagrelor had a primary efficacy outcome event than in the placebo group (404 [7.3%] of 5558 vs 480 [8.6%] of 5596; HR 0.85 [95% CI 0.74-0.97], p=0.013). The same effect was not observed in patients without PCI (p=0.76, pinteraction=0.16). The proportion of patients with cardiovascular death was similar in both treatment groups (174 [3.1%] with ticagrelor vs 183 (3.3%) with placebo; HR 0.96 [95% CI 0.78-1.18], p=0.68), as well as all-cause death (282 [5.1%] vs 323 [5.8%]; 0.88 [0.75-1.03], p=0.11). TIMI major bleeding occurred in 111 (2.0%) of 5536 patients receiving ticagrelor and 62 (1.1%) of 5564 patients receiving placebo (HR 2.03 [95% CI 1.48-2.76], p

Kai-Chun Cheng,1,* Yingxiao Li,1,2,* Wei-Ting Chang,2,3 Feng Yu Kuo,4 Zhih-Cherng Chen,3,5 Juei-Tang Cheng2,6 1Department of Psychosomatic Internal Medicine, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima 890-8544, Japan; 2Department of Medical Research, Chi-Mei Medical Center, Yong Kang, Tainan City 71003, Taiwan; 3Department of Cardiology, Chi-Mei Medical Center, Yong Kang, Tainan City 71003, Taiwan; 4Cardiovascular Center, Kaohsiung Veterans General Hospital, Kaohsiung City 81362, Taiwan; 5Department of Pharmacy, Chia Nan University of Pharmacy and Science, Jean-Tae, Tainan City 71701, Taiwan; 6Institute of Medical Sciences, Chang Jung Christian University, Gueiren, Tainan City 71101, Taiwan *These authors contributed equally to this work Background: Metabolic syndrome (MS) is known to be associated with hypertension, insulin resistance, and dyslipidemia, and it raises the risk for cardiovascular diseases and diabetes mellitus. Telmisartan is used in clinic as an angiotensin II receptor blocker and it is also identified as activating peroxisome proliferator-activated receptors δ (PPARδ). Activation of PPARδ produced beneficial effects on fatty acid metabolism and glucose metabolism. This study aims to investigate the effects of telmisartan on the modulation of MS in rats fed a high-fat/high-sodium diet. Methods: Rats were fed with a high-fat/high-sodium diet and received injections of streptozotocin at low dose to induce MS. Then, rats with MS were treated with telmisartan. The weight, glucose tolerance, and insulin sensitivity were measured. The lipid profiles were also obtained. The weights of retroperitoneal and epididymal fat pads were determined. The role of PPARδ in telmisartan treatment was identified in rats pretreated with the specific antagonist GSK0660. Results: The results showed that telmisartan, but not losartan, significantly reduced plasma glucose and plasma insulin, and improved insulin resistance in rats with MS. Telmisartan also decreased blood pressure and lipids more significantly than losartan. Moreover, GSK0660 effectively reversed the effects of telmisartan in the MS rats. In the MS group, telmisartan activated PPARδ to enhance the levels of phosphorylated GLUT4 in muscle or the expression of phosphoenolpyruvate carboxykinase (PEPCK) in the liver, which was also abolished by GSK0660. Telmisartan is useful to ameliorate hypertension and insulin resistance in rats with MS. Telmisartan improves the insulin resistance through increased expression of GLUT4 and down-regulation of PEPCK via PPARδ-dependent mechanisms. Conclusion: Telmisartan has been proven to ameliorate MS, particularly in the prediabetes state. Therefore, telmisartan is suitable to develop for the management of MS in clinics. Keywords: metabolic syndrome, telmisartan, PPARδ, GSK0660, diet&nbsp

OBJECTIVE To evaluate whether home or ambulatory blood pressure (BP) monitoring was associated with preclinical hypertensive cardiovascular target organ damage (TOD). METHODS We enrolled participants with prehypertension and stage 1 hypertension from 11 medical centers within the Taiwan hypertension-associated cardiac disease consortium. Recordings of clinical BP measurement, ambulatory BP monitoring for 24 hours, and home BP monitoring during morning and evening were made. The measured parameters of target organ damage included left ventricular mass index (LVMI), left atrial volume index (LAVI), and carotid-femoral pulse wave velocity (PWV). RESULTS Data were collected from 561 study participants (mean age, 65.0 ± 10.8 years; men, 61.3%). Morning and evening home BP values were slightly higher than the daytime and nighttime ABP values (difference for systolic morning-daytime/evening-nighttime, 7.3 ± 14.2/11.3 ± 18.5 mm Hg, P < .001; for diastolic, 5.4 ± 9.4/7.3 ± 12.1, P < .001). Daytime ambulatory (r = 0.114), nighttime ambulatory (r = 0.130), morning home (r = 0.310), and evening home (r = 0.220) systolic BPs (SBPs) were all associated with LVMI (all P < .05). The correlation coefficient was significantly greater for the relationship between daytime home SBP and LVMI than for the relationship between ambulatory SBP and LVMI (P < .01). The goodness of fit of the association between SBP and LVMI improved by adding home daytime SBP to the other SBPs (P < .001). Similar findings were observed for LAVI, but not for PWV. CONCLUSION These findings indicate that morning SBP assessed by home monitoring appears to be a better predictor than other BP measures to determine preclinical hypertensive cardiovascular damage in patients with early-stage hypertension.

Peroxisome proliferator-activated receptor δ (PPARδ), the predominant PPAR subtype in the heart, is known to regulate cardiac function. PPARδ activation may inhibit cardiac hypertrophy in H9c2 cells while the potential mechanism has not been elucidated. Then, H9c2 cells incubated with high glucose to induce hypertrophy were used to investigate using GW0742 to activate PPARδ. The fluorescence assays were applied to determine the changes in cell size, cellular calcium levels, and free radicals. Western blot analyses for hypertrophic signals and assays of messenger RNA (mRNA) levels for hypertrophic biomarkers were performed. In H9c2 cells, GW0742 inhibited cardiac hypertrophy. In addition, increases in cellular calcium and hypertrophic signals, including calcineurin and nuclear factor of activated T-cells, were reduced by GW0742. This reduction was parallel to the decrease in the mRNA levels of biomarkers, such as brain/B-type natriuretic peptides and β-myosin heavy chain. These effects of GW0742 were dose-dependently inhibited by GSK0660 indicating an activation of PPARδ by GW0742 to alleviate cardiac hypertrophy. Moreover, free radicals produced by hyperglycemia were also markedly inhibited by GW0742 and were later reversed by GSK0660. GW0742 promoted the expression of thioredoxin, an antioxidant enzyme. Direct inhibition of reactive oxygen species by GW0742 was also identified in the oxidant potassium bromate stimulated H9c2 cells. Taken together, these findings suggest that PPARδ agonists can inhibit free radicals, resulting in lower cellular calcium for reduction of hypertrophic signaling to alleviate cardiac hypertrophy in H9c2 cells. Therefore, PPARδ activation can be used to develop agent(s) for treating cardiac hypertrophy.

Ginsenoside Rh2 (Rh2) is an active principal ingredient contained in ginseng (Panax ginseng Meyer), a medicinal herb used to enhance health worldwide. The present study is designed to investigate the effect of Rh2 on myocardial fibrosis in diabetic rats. In a streptozotocin-induced model of type-1 diabetic rats (STZ-diabetic rats), the increased fasting blood glucose levels and heart weight/body weight (HW/BW) ratio were substantially alleviated by Rh2. Moreover, Rh2 improved cardiac performance in STZ-diabetic rats. Histological results from Masson staining showed that Rh2 attenuated cardiac fibrosis in STZ-diabetic rats. The effects of Rh2 were reversed by GSK0660 at a dose sufficient to inhibit peroxisome proliferator-activated receptor δ (PPARδ) in STZ-diabetic rats. The role of PPARδ was subsequently investigated in vitro. Rh2 restored the decreased PPARδ expression level in high glucose-cultured cardiomyocytes. Moreover, increased protein levels of fibrotic signals, including signal transducer and activator of transcription 3 (STAT3), connective tissue growth factor (CCN2) and fibronectin, were reduced by Rh2 in high glucose-cultured cardiomyocytes. These effects of Rh2 were reversed by GSK0660 or siRNA specific for PPARδ Taken together, PPARδ activation may inhibit STAT3 activation to reduce CCN2 and fibronectin expression in diabetic rats with cardiac fibrosis. Moreover, Rh2 improves cardiac function and fibrosis by increasing PPARδ signaling. Therefore, Rh2 is suitable to develop as an alternative remedy for cardiac fibrosis.

Background Patients with unprovoked venous thromboembolism ( VTE ) are at an increased risk of mortality, but whether their cardiovascular risks also increase remains to be determined. We aimed to investigate the factors associated with overall mortality and major adverse cardiovascular events in patients with unprovoked VTE . Methods and Results We identified 2154 patients newly diagnosed with unprovoked VTE from Taiwan's National Health Insurance Database between 2000 and 2013, excluding those with reversible etiologies, underlying cancer, or autoimmune diseases. These patients with VTE were compared with an age‐, sex‐, and cardiovascular risk‐matched cohort of 4308 controls. The risk of mortality and major adverse cardiovascular events in patients with VTE was 2.23 ( CI , 1.93–2.57; P CI , 1.65–2.09; P VTE . Among patients with VTE , advanced age, male sex, and comorbid diabetes mellitus indicated a higher incidence of mortality and major adverse cardiovascular events. Conversely, comorbid hyperlipidemia attenuated these risks. Conclusions This nation‐wide cohort study revealed that patients with unprovoked VTE , particularly older males with diabetes mellitus, had an elevated risk of both mortality and cardiovascular events. Risk of mortality and major adverse cardiovascular events were highest within the first year after diagnosis and persisted during the 10 years of follow‐up.

The present study investigates the changes of peroxisome proliferator-activated receptorsδ(PPARδ) expression and troponin phosphorylation in heart of rats which were treated with doxorubicin (DOX). Wistar rats which were treated with DOX according to a previous method. The protein levels of PPARδand troponin phosphorylation were measured using Western blot. The PPARδexpression in heart was markedly reduced in DOX-treated rats showing a marked decrease in cardiac dP/dT and cardiac output. Also, cardiac troponin phosphorylation was lowered in DOX-treated rats. Meanwhile, combined treatment with the agonist of PPARδ(GW0742) reversed the decrease of cardiac dP/dT and cardiac output in DOX-treated rats. Then, primary cultured cardiomyocytes from neonatal rats were used to measure the changes of calcium concentration in cells. In addition to both decrease of PPARδexpression and troponin phosphorylation in neonatal cardiomyocytes by DOX, a marked decrease of calcium concentration was also observed. Our results suggest the mediation of cardiac PPARδin DOX-induced cardiotoxicity in rats. Thus, activation of PPARδmay restore the expression of p-TnI and the cardiac performance in DOX-induced cardio toxicity in rats.

Background Pulmonary hypertension ( PH ) is a rare but fatal condition. Large‐scale studies to examine the prognostic factors are lacking. In the present study, we aimed to investigate the factors associated with overall mortality in PH patients. Methods and Results Based on Taiwan's National Health Insurance Database, we identified 1092 newly identified PH patients between 1999 and 2011. These patients were matched with 8736 healthy subjects based on propensity score calculated with age, sex, and chronic cardiovascular risk factors. Overall mortality, death incidence rate ratio, and hazard ratio were calculated. Patients with PH had a higher mortality than controls (56.45 versus 18.51 per 1000 person‐years, P CI : 2.92–3.73, P PH patients at 1, 5, and 10 years were 87.9%, 72.5%, and 62.6%, respectively, which were significantly lower than controls with 98.4%, 90.8%, and 83.6% at 1, 5, and 10 years, respectively. Among patients with PH , the mortality rate was higher in the older and male patients. However, after stratifying by age and sex, the younger (PH , chronic obstructive pulmonary disease and pulmonary embolism led to most cases of mortality (adjusted hazard ratio: 3.2, 95% CI : 2.76–3.71 and 4.64, 95% CI : 2.74–7.87, P Conclusions PH has high mortality, especially in females, and patients with younger age and with chronic diseases. Chronic obstructive pulmonary disease and pulmonary embolism contributed to an increased risk of mortality in PH patients.

Increase of peroxisome proliferator-activated receptor δ (PPARδ) expression by digoxin in the heart of diabetic rats has been documented. The present study investigated the mediation of PPARδ in lipid metabolism improved by digoxin in the heart of diabetic rats and in the hyperglycemia-treated cardiomyocytes using the primary cultured cardiomyocytes from neonatal rat. The lipid deposition within the heart section was assessed in diabetic rats by oil red O staining. The fatty acid oxidation genes in cardiomyocytes were also examined. Inhibitor of calcium ions and siRNA-PPARδ were employed to investigate the potential mechanisms. After a 20-day digoxin treatment, the PPARδ expression was elevated in hearts of diabetic rats while the cardiac lipid deposition was reduced. In neonatal cardiomyocytes, digoxin also caused an increase in expressions of PPARδ and fatty acid oxidation genes. But both actions of digoxin were blocked by BAPTA-AM to chelate calcium ions and by siRNA-PPARδ in cardiomyocytes. The obtained results show that increase of PPARδ by digoxin is related to regulation of fatty acid oxidation genes in cardiac cells mediated by calcium-triggered signals.

To evaluate the efficacy and safety of valsartan in Taiwanese patients with essential hypertension.This 12-week multi-center, open-label, observational, post-marketing surveillance study enrolled 2046 hypertensive patients who were prescribed valsartan 80 or 160 mg as monotherapy or in combination with other antihypertensives based on clinical judgment. The primary endpoint was the incidence rate of dizziness with valsartan 160 mg monotherapy or combination therapy at Week 4. Secondary endpoints included the blood-pressure-lowering efficacy and the overall safety and tolerability of valsartan at Weeks 4 and 12.The monotherapy and combination groups had comparable baseline characteristics. At Week 4, monotherapy was found non-inferior to combination for incidence rate of dizziness (monotherapy, 9.25%; combination, 10%; difference in incidence of dizziness, 0.75%; 95% CI - 0.61% to 2.12%; non-inferiority margin, -1.33%;WaldTest approach). Greater blood pressure (BP) reduction was noted atWeek 12 than atWeek 4.The antihypertensive effect was greater with combination therapy and the 160-mg dose. BP control (systolic140 mmHg or diastolic90 mmHg) was achieved in 80-90% patients.Valsartan was well tolerated; most commonly reported adverse events included dizziness, headache, constipation and cough.Valsartan is an effective treatment option for essential hypertension in Taiwanese patients.

To assess the efficacy, safety, and tolerability of a combination of 10 mg ezetimibe and 20 mg simvastatin in Taiwanese patients with hypercholesterolemia.A prospective, open-label, multi-center, hospital-based cohort study was conducted to evaluate the efficacy, safety, and tolerability of a single tablet combination of ezetimibe/simvastatin for the treatment of hypercholesterolemia. Taiwanese adults without low-density lipoprotein cholesterol (LDL-C) goal achievement, based on the National Cholesterol Education Program Adult Treatment Panel III guidelines, were treated with ezetimibe/simvastatin once daily for 6 weeks. The primary endpoint was the percentage of patients achieving LDL-C treatment goals after 6 weeks of treatment. Secondary endpoints included percentage change from baseline of LDL-C, total cholesterol, high-density lipoprotein cholesterol, and triglyceride. Safety and tolerability were assessed via clinical and laboratory examinations. The clinicaltrial.gov identifier of this study was NCT00654628.In total, 173 patients with a mean age of 57.9 ± 10.4 years were included. Of these, 57.8% were female and the average body mass index was 25.5 ± 3.4 kg/m(2). After 6 weeks of treatment, the great majority of the patients had reached their treatment goals (90.4% for LDL-C; 87% for TC; and 59% for TG). LDL-C levels were significantly reduced from 156.8 ± 30.8 mg/dL at baseline to 75.9 ± 25.4 mg/dL (51.4%, P 0.0001) after only 6 weeks of therapy. Forty-nine adverse events (AEs), including one non-drug related serious AE, were reported. For non-serious AEs, the most common reported AEs during the entire study period were myalgia and upper respiratory infection (both n = 7). Nine patients dropped out of the study, reportedly due to AEs.A single tablet combination of 10 mg ezetimibe and 20 mg simvastatin in Taiwanese patients with hypercholesterolemia provided high LDL-C goal attainment rates and resulted in significant reductions in LDL-C.

BACKGROUND AND PURPOSE Digoxin has been used as an inotropic agent in heart failure for a long time. Troponin I (TnI) phosphorylation is related to cardiac contractility, and the genes are regulated by peroxisome proliferator-activated receptors (PPARs). Our previous studies indicated that cardiac abnormality related to the depressed expression of PPARδ in the hearts of STZ rats is reversed by digoxin. However, the cellular mechanisms for this effect of digoxin have not been elucidated. The aim of the present study was to investigate possible mechanisms for this effect of digoxin using the H9c2 cell line cultured in high glucose (HG) conditions. METHODS The effects of digoxin on PPARδ expression, intracellular calcium and TnI phosphorylation were investigated in cultured H9c2 cells, maintained in a HG medium, by using Western blot analysis. RESULTS Digoxin increased PPARδ expression in H9c2 cells subjected to HG conditions, and increase the intracellular calcium concentration. This effect of digoxin was blocked by BAPTA-AM at concentrations sufficient to chelate calcium ions. In addition, the calcineurin inhibitor cyclosporine A and KN93, an inhibitor of calcium/calmodulin-dependent protein kinase, inhibited this action. Digoxin also increased TnI phosphorylation and this was inhibited when PPARδ was silenced by the addition of RNAi to the cells. Similar changes were observed on the contraction of H9c2 cells. CONCLUSION The results suggest that digoxin appears, through calcium-triggered signals, to reverse the reduced expression of PPARδ in H9c2 cells caused by HG treatment.

Radial artery occlusion (RAO) occurs in 2% to 18% of patients after transradial access (TRA) cardiac catheterization. Using a kaolin-filled pad (QuikClot) reduces compression time during TRA and might reduce RAO. We examined the RAO risk with the kaolin-filled pad after TRA cardiac catheterization. This was a prospective cross-sectional study of 260 patients who underwent TRA cardiac catheterization in a cardiac ward of a Medical Center from 2012 to 2016. Patients were randomly assigned to 1 of 2 groups: the case group (n = 130) was postoperatively treated with a kaolin-filled pad, and the control group (n = 130) was treated with conventional hemostasis. Color duplex ultrasound was used to evaluate the 24-hour and 1-month postoperative radial artery flow velocity, diameter, patency, and RAO risk. RAO risk was not significantly different between the case and control groups after 24 hours (4.6% vs 5.4%, P = .776) or after 1 month (5.4% vs 6.1%, P = .789), regardless of whether it was a first TRA cardiac catheterization (after 24 hours [P = .153] or after 1month [P = .617], respectively) or a repeated TRA cardiac catheterization (after 24 hours [P = .754] or after 1month [P = .753], respectively). Using a kaolin-filled pad after TRA cardiac catheterization did not significantly reduce RAO risk compared with conventional hemostasis.

The absorption efficiency of cholesterol is closely correlated to dietary phytosterol content and determined by genetic factors. The ATP-binding cassette (ABC) transporters ABCG5 and ABCG8 act as a sterol efflux pump to regulate the absorption of cholesterol and phytosterol. The levels of cholesterol and phytosterol associated with a Chinese diet are very different from those associated with a Western diet. This study aims to explore the association between serum total cholesterol/LDL-C levels and ABCG5/ABCG8 polymorphisms in a Taiwanese population consuming an ordinary Chinese diet. A total of 1,046 subjects (894 men and 152 women) were recruited in a hospital-based health check-up center in Kaohsiung Medical University Hospital. Five nonsynonymous polymorphisms of Q604E (ABCG5), D19H, C54Y, T400 K and A632 V (ABCG8) were analyzed by TaqMan genotyping assay. Analysis showed that the D19H polymorphism of the ABCG8 gene was significantly associated with serum total cholesterol, LDL-C levels and HOMA-IR index. Adjusting for sex and age, subjects with the D19H (GC) genotype were significantly associated with a threefold higher risk of high cholesterol and LDL-C levels than subjects with D19 (GG). These results suggest that the D19H polymorphism of ABCG8 could be considered a susceptible gene marker indicating an increased likelihood of developing high cholesterol and LDL-C levels in Taiwanese consuming an ordinary Chinese diet. It is supposed that the coexistence of higher insulin resistance and hypercholesterolemia for carriers of the D19H polymorphism may result in a greater risk of cardiovascular disease.

In this study, we investigated the acute hemodynamic effects of an infusion of the endothelin-1 (ET-1)-A-selective receptor antagonists BQ-610 and BQ-123 in heatstroke rats with circulatory shock and cerebral ischemia. Heatstroke was induced by putting the anesthetized adult Sprague-Dawley rats into an ambient temperature of 42°C. The moment in which the mean arterial pressure dropped irreversibly from the peak for an extent of 25 mmHg was taken as the onset of heatstroke. The interval between initiation of heat exposure and heatstroke onset was found to be about 80 min for rats treated with vehicle solution. When the animals were exposed to 42°C for 80 min, hyperthermia, arterial hypotension, decrement of cardiac output (due to decreased stroke volume and decreased total peripheral resistance), increment of plasma ET-1 and tumor necrosis factor-α, and increment of cerebral ischemia and injury markers were manifested. Prior antagonism of ET-1 A receptors with BQ-610 (0.5 mg/kg, i.v.) or BQ-123 (1 mg/kg, i.v.), but not ET-1B receptors with BQ-788 (0.5 mg/kg, i.v.), 60 min before the initiation of heat exposure, appreciably alleviated hyperthermia, arterial hypotension, decreased cardiac output, increment of tumor necrosis factor-α, and increment of cerebral ischemia (e.g., glutamate and lactate/pyruvate ratio) and injury (e.g., glycerol) markers exhibited during heatstroke. The data indicates that ET-1A receptor antagonism may maintain appropriate levels of mean arterial pressure and cerebral circulation during heatstroke by reducing production of tumor necrosis factor-α. Keywords:: blood pressure, cardiac output, endothelin, heatstroke, receptor

BACKGROUND AND AIMS: Agents having a positive inotropic effect on the heart are widely used for the treatment of heart failure. However, these agents have the side effect of altering heart rate. It has been established that peroxisome proliferator-activated receptor δ (PPARδ) is mediated in cardiac contraction, however the effect on heart rate is unknown. Thus, we used an agonist of PPARδ, GW0742, to investigate this issue in the present study. METHODS AND RESULTS: We used isolated hearts in Langendorff apparatus and hemodynamic analysis in catheterized rats to measure the actions of GW0742 extra-vivo and in vivo. In diabetic rats with heart failure, GW0742 at a dose sufficient to activate PPARδ reversed cardiac contraction without changes in heart rate. In normal rats, PPARδ enhanced cardiac contractility and hemodynamic dP/dtmax significantly more than dobutamine. Both actions were diminished by GSK0660 at a dose enough to block PPARδ. However, GW0742 at the same dose failed to modify heart rate, although it did produce a mild increase in blood pressure. Detection of intracellular calcium level and Western blotting analysis showed that the intracellular calcium concentration and troponin I phosphorylation were both enhanced by GW0742. CONCLUSION: Activation of PPARδ by GW0742 increases cardiac contractility but not heart rate. Thus, PPARδ may be a suitable target for the development of inotropic agents to treat heart failure without changing heart rate.

Background An impairment of cardiovascular function in streptozotocin (STZ)-diabetic rats has been mentioned within 5 days-to-3 months of induction. ATP-sensitive potassium (KATP) channels are expressed on cardiac sarcolemmal membranes. It is highly responsive to metabolic fluctuations and can have effects on cardiac contractility. The present study attempted to clarify the changes of cardiac KATP channels in diabetic disorders. Methods Streptozotocin-induced diabetic rats and neonatal rat cardiomyocytes treated with a high concentration of glucose (a D-glucose concentration of 30 mM was used and cells were cultured for 24 hr) were used to examine the effect of hyperglycemia on cardiac function and the expression of KATP channels. KATP channels expression was found to be linked to cardiac tonic dysfunction, and we evaluated the expression levels of KATP channels by Western blot and Northern blot analysis. Results The result shows diazoxide produced a marked reduction of heart rate in control group. Furthermore, the methods of Northern blotting and Western blotting were employed to identify the gene expression of KATP channel. Two subunits of cardiac KATP channel (SUR2A and kir 6.2) were purchased as indicators and showed significantly decreased in both diabetic rats and high glucose treated rat cardiac myocytes. Correction of hyperglycemia by insulin or phlorizin restored the gene expression of cardiac KATP in these diabetic rats. Conclusions Both mRNA and protein expression of cardiac KATP channels are decreased in diabetic rats induced by STZ for 8 weeks. This phenomenon leads to result in desensitization of some KATP channel drugs.

Background/Aims: The role of opioid receptors in the regulation of vascular function remains unclear. In the current study, we evaluated the ability of loperamide, a peripheral opioid receptor agonist, to regulate blood pressure in spontaneously hypertensive rats (SHRs) and examined the mechanism(s) by which loperamide exerts its effects. Methods: In male SHRs, mean arterial pressure (MAP) was measured and hemodynamic analysis was recorded. Additionally, the isometric tension of aortic rings isolated from SHRs was determined. Results: Loperamide dose-dependently decreased MAP in SHRs but not in the normal group of Wistar-Kyoto rats. This reduction of MAP in conscious SHRs was abolished by the selective opioid µ-receptor antagonist cyprodime, but not by naloxonazine, the µ1-opioid receptor antagonist. However, cardiac output was not altered by loperamide in anesthetized SHRs. Moreover, loperamide-induced relaxation in isolated aortic rings precontracted with phenylephrine or vasopressin. This relaxation was abolished by cyprodime, but not by naloxonazine. Loperamide-induced relaxation was also attenuated by glibenclamide, an ATP-sensitive potassium (KATP) channel blocker. Additionally, vasodilatation by loperamide was reduced by an inhibitor of protein kinase A (PKA) and enhanced by an inhibitor of phosphodiesterases. Conclusion: We suggest that loperamide can lower MAP in SHRs via µ2-opioid receptor-dependent cAMP-PKA pathway that induces vascular relaxation by opening KATP channels.

The present study is designed to investigate the role of peroxisome proliferator-activated receptors delta (PPARdelta) in the action of digoxin in diabetic rats showing cardiac hypertrophy. We used Wistar rats to induce diabetes by injection of streptozotocin (STZ-rat) and examined the effect of digoxin on PPARdelta expression in these hyperglycemic rats (STZ-rat) at 10 weeks later. We measured the changes of body weight, water intake, and food intake in three groups of age-matched rats; the vehicle treated normal control (Wistar rats), the vehicle treated STZ-rats, and the digoxin-treated STZ-rats. Cardiac output, heart rate, and blood pressure in addition to plasma insulin or glucose level were also determined. The mRNA and protein levels of PPARdelta were measured using Northern and Western blotting, respectively. Cardiac output, heart rate, and blood pressure were markedly reduced while food intake, water intake, and blood glucose were raised in STZ-rats showing lower body weight and plasma insulin as compared with the vehicle-treated controls. After a 20-day of digoxin treatment, cardiac output was raised in STZ-rats but the diabetic parameters were not modified. The PPARdelta expressions, both mRNA and protein, were markedly elevated in the hearts of STZ-rats by digoxin treatment. The related signals with PPARdelta, such as carnitine palmitoyltransferase 1B (CPT1B), acetyl-coenzyme A, carboxylase alpha (ACC1), fatty acid synthase (FAS), and troponin I, were also raised. The increase of cardiac output by digoxin was reversed by the combined treatment with PPARdelta antagonist GSK0660. Thus, we suggest a new finding that PPARdelta is involved in digoxin induced cardiac inrotropic action.

Background Human recombinant activated protein C (APC) has been found to be beneficial in treating heatstroke in both humans and rats. Here, we further investigated the possible mechanism underlying the therapeutic action exerted by APC in experimental heatstroke. Methods Unanesthetized and unrestrained mice were exposed to an ambient temperature of 42.4°C for 1 hour to induce heatstroke. They were given normal saline or APC (5 mg/kg of body weight, intravenously) 1 hour after the termination of heat stress. Their physiologic and biochemical parameters were continuously monitored for 4 hours after cessation of heat stress. Mice that survived on day 4 of heat treatment were considered survivors. Results When the vehicle-treated mice underwent heat treatment, the fraction survival and core temperature at 4 hours of body heating were found to be 0 of 12 and 33.8 ± 0.6°C, respectively. Administration of APC 1 hour after the cessation of heat stress rescued the mice from heat-induced death (fraction survival, 12 of 12) and reduced hypothermia (core temperature, 37.4 ± 0.2°C). Heat-induced apoptosis in the hypothalamus was significantly reduced by APC. The increased levels of cellular ischemia (eg, glutamate, lactate-to-pyruvate ratio, nitrite, and dihydroxybenzoic acid) and damage (eg, glycerol) markers in the hypothalamus during heatstroke were also decreased significantly by APC therapy. The hypothalamic levels of tumor necrosis factor- α (a proinflammatory cytokine) that are upregulated in heat-stressed mice were significantly lower in APC-administered mice. Conclusions Our results show that human recombinant APC improves heatstroke through restoration of normal hypothalamic and thermoregulatory function.

Background Transgenic mice have been used to examine the role of heat shock protein (HSP)72 in experimental heatstroke. Transgenic mice that were heterozygous for a porcine HSP70β gene ([+] HSP72) and transgene-negative littermate controls ([-] HSP72), under pentobarbital sodium anesthesia, were subjected to heat stress to induce heatstroke. It was found that the overexpression of HSP72 in multiple organs improved survival during heatstroke by reducing hypotension and cerebral ischemia and damage in mice. Herein we attempted to further assess the effect of heat exposure on thermoregulatory function, hypothalamic integration, and survival in unrestrained, unanesthetized [+]HSP72 and compare with those of [-]HSP72. In this research with the transgenic mice, we first conducted several biochemical, physiologic and histological determinations and then investigated the beneficial effects of HSP72 overexpression on the identified hypothalamic deficits, thermoregulatory dysfunction, and mortality during heatstroke. Results We report here that when [-]HSP72 mice underwent heat stress (ambient temperature 42.4°C for 1 h), the fraction survival and core temperature at 4 h after heat stress were found to be 0 of 12 and 34.2°C ± 0.4°C, respectively. Mice that survived to day 4 after heat stress were considered as survivors. In [+]HSP72 mice, when exposed to the same heat treatment, both fraction survival and core temperature values were significantly increased to new values of 12/12 and 37.4°C ± 0.3°C, respectively. Compared to [-]HSP mice, [+]HSP72 mice displayed lower hypothalamic values of cellular ischemia (e.g., glutamate and lactate-to-pyruvate ratio) and damage (e.g., glycerol) markers, pro-oxidant enzymes (e.g., lipid peroxidation and glutathione oxidation), pro-inflammatory cytokines (e.g., interleukin-1beta and tumor necrosis factor-alpha), and neuronal damage score evaluated 4 h after heat stress. In contrast, [+]HSP72 mice had higher hypothalamic values of antioxidant defences (e.g., glutathione peroxidase and glutathione reductase), ATP, and HSP72 expression. Conclusion This study indicates that HSP72 overexpression appears to be critical to the development of thermotolerance and protection from heat-induced hypothalamic ischemic and oxidative damage.

Intra-aortic balloon pumping (IABP) is widely used for hemodynamic support in critical patients with cardiogenic shock (CS). We examined whether the in-hospital mortality of patients in Taiwan treated with IABP has recently declined. We used Taiwan's National Health Insurance Research Database to retrospectively review the in-hospital all-cause mortality of 9952 (7146 men [71.8%]) 18-year-old and older patients treated with IABP between 1998 and 2008. The mortality rate was 13.84% (n = 1377). The urbanization levels of the hospitals, and the number of days in the intensive care unit, of hospitalization, and of IABP treatment, and prior percutaneous coronary intervention (PCI) were associated with mortality. Seven thousand six hundred thirty-five patients (76.72%) underwent coronary artery bypass grafting (CABG) surgery, and 576 (5.79%) underwent high-risk PCI with IABP treatment. The number of patients treated with IABP significantly increased during this decade (ptrend < 0.0001), the in-hospital all-cause mortality for patients treated with IABP significantly decreased (ptrend = 0.0243), but the in-hospital all-cause mortality of patients who underwent CABG and PCI plus IABP did not decrease. In conclusion, the in-hospital mortality rate of IABP treatment decreased annually in Taiwan during the study period. However, high-risk patients who underwent coronary revascularization with IABP had a higher and unstable in-hospital mortality rate.

Naltrexone, a nonselective antagonist of opioid receptors, is found to be beneficial in protecting against heatstroke. Further investigation using selective mu, delta, and kappa opioid receptor antagonists are needed to prove the involvement of specific receptors in heatstroke. Rats under sodium pentobarbital anesthesia were exposed to high ambient temperature of 43 degrees C to induce heatstroke. Control rats were exposed to 24 degrees C. In rats treated with normal saline 20 minutes before heat stress, the values for survival time were found to be 89-101 minutes. Intravenous administration of CTAP (a selective mu-opioid receptor antagonist; 50-200 microg/kg), but not nor-binaltorphimine (20-200 microg/kg; a kappa-opioid receptor antagonist) or ICI-174864 (50-500 microg/kg; a delta-opioid receptor antagonist), significantly increased the survival time to new values of 180-212 minutes. In vehicle-treated rats after heatstroke onset, the values for core temperature, intracranial pressure, and the extracellular markers for ischemia (eg, glutamate and lactate/pyruvate ratio) or damage (eg, glycerol) and neuronal damage scores in striatum were significantly higher than those of normothermic controls. In contrast, the values for mean arterial pressure, cerebral perfusion pressure, cerebral blood flow, and brain partial pressure of O2 were significantly lower than those of normothermic controls. The heatstroke-induced hyperthermia, arterial hypotension, intracranial hypertension, cerebral hypoperfusion and hypoxia, and increased levels of cellular ischemia and damage markers in striatum were all significantly attenuated by prior administration of CTAP. The data indicate that prior antagonism of mu-opioid receptors protects against circulatory shock and cerebral ischemia during heatstroke.

Thrombomodulin is an endothelial glycoprotein that decreases thrombin activity and activates protein C. A recent study has shown that G-33A promoter mutation of the thrombomodulin gene occurs particularly in Asians. In this study, we analyzed the distribution of G-33A mutation in the promoter region of the thrombomodulin gene in the Chinese population and determined whether the mutation might be a risk for coronary artery disease (CAD). In addition, the influence of this mutation on plasma soluble thrombomodulin levels in patients with CAD was also examined. We studied 320 consecutive patients (mean age 63 years; 73% men) with CAD and 200 age- and sex-matched control subjects. Screening for thrombomodulin G-33A promoter mutation was conducted using polymerase chain reaction, single-strand conformation polymorphism, and direct deoxyribonucleic acid sequencing. The frequency of the G-33A mutation (GA+AA genotypes) was significantly higher in the CAD group (23.8% vs 15.5%, odds ratio [OR] 1.70, p = 0.031). Multiple logistic regression analysis showed that the mutation was an independent risk factor (OR 1.81, p = 0.016) for CAD, as was hypertension (OR 1.44, p = 0.040), diabetes mellitus (OR 2.50, p0.001), and smoking (OR 2.15, p0.001). In CAD patients with GG genotype, the soluble thrombomodulin level increased with the extent of CAD (36 +/- 15 vs 47 +/- 18 vs 55 +/- 36 ng/ml in 1-, 2-, or 3-vessel CAD, p0.001). However, in CAD patients with G-33A mutation, there was no difference between the levels of soluble thrombomodulin (39 +/- 17 vs 37 +/- 15 vs 42 +/- 18 ng/ml, p = NS) in 1-, 2-, or 3-vessel CAD. Our observations suggest that there is a significant association of the G-33A mutation in thrombomodulin gene with CAD, and this mutation may influence the soluble thrombomodulin levels in patients with CAD.

Background Despite the known risk of diabetes-induced cardiac fibrosis, less is known about whether diabetes causes an altered cardiac phenotype independent of coronary atherosclerosis. Peroxisome proliferator-activated receptor δ (PPARδ), a versatile regulator of metabolic homeostasis, may be a potential therapeutic target. Herein we investigated the effectiveness of telmisartan, a unique angiotensin receptor blocker that increases PPARδ expression, in improving left ventricular remodeling in diabetic humans and rats. Methods In this longitudinal, prospective study, we enrolled 15 diabetic patients receiving telmisartan (20 mg/day) for 12 weeks. After treatment, strain was measured and compared with the baseline value. Using streptozotocin to induce type 1 diabetes rat model, we measured PPARδ expression and downstream targets. Results After treatment with telmisartan, both longitudinal and circumferential strains improved in diabetic patients. Compared with that of controls, the diabetic rat heart developed significant fibrosis, which markedly decreased after treatment with telmisartan (30 mg/kg/day, orally) for 7 days. After incubation with 30 mM glucose, rat cardiomyocytes showed a significant down-regulation of PPARδ. Interestingly, the increased expression of fibrosis-associated proteins, including signal transducer and activator of transcription 3 (STAT3) was attenuated by the co-incubation of GW0742, a PPARδ agonist. By knockdown or inhibition of STAT3, the hyperglycemia related high expression of fibrosis associated targets was reversed. Independent from the hyperglycemic incubation, STAT3 over-expression led to similar results. Conversely, in the presence of GSK0660, a PPARδ inhibitor, the protective effects of telmisartan were diminished. Conclusion Telmisartan improved the hyperglycemia-induced cardiac fibrosis through the PPARδ/STAT3 pathway.Graphical abstractSummary of the mechanism of telmisartan’s effect on the suppression of hyperglycemia-induced cardiac fibrosis through PPARδ instead of the AMPK pathway. PPARδ peroxisome proliferator-activated receptor δ, STAT3 signal transducer and activator of transcription 3, CTGF connective tissue growth factor, MMP9 matrix metallopeptidase 9