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1.
JAMA ; 2020 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-32219386

RESUMO

Importance: Additional treatments are needed for heart failure with reduced ejection fraction (HFrEF). Sodium-glucose cotransporter 2 (SGLT2) inhibitors may be an effective treatment for patients with HFrEF, even those without diabetes. Objective: To evaluate the effects of dapagliflozin in patients with HFrEF with and without diabetes. Design, Setting, and Participants: Exploratory analysis of a phase 3 randomized trial conducted at 410 sites in 20 countries. Patients with New York Heart Association classification II to IV with an ejection fraction less than or equal to 40% and elevated plasma N-terminal pro B-type natriuretic peptide were enrolled between February 15, 2017, and August 17, 2018, with final follow-up on June 6, 2019. Interventions: Addition of once-daily 10 mg of dapagliflozin or placebo to recommended therapy. Main Outcomes and Measures: The primary outcome was the composite of an episode of worsening heart failure or cardiovascular death. This outcome was analyzed by baseline diabetes status and, in patients without diabetes, by glycated hemoglobin level less than 5.7% vs greater than or equal to 5.7%. Results: Among 4744 patients randomized (mean age, 66 years; 1109 [23%] women; 2605 [55%] without diabetes), 4742 completed the trial. Among participants without diabetes, the primary outcome occurred in 171 of 1298 (13.2%) in the dapagliflozin group and 231 of 1307 (17.7%) in the placebo group (hazard ratio, 0.73 [95% CI, 0.60-0.88]). In patients with diabetes, the primary outcome occurred in 215 of 1075 (20.0%) in the dapagliflozin group and 271 of 1064 (25.5%) in the placebo group (hazard ratio, 0.75 [95% CI, 0.63-0.90]) (P value for interaction = .80). Among patients without diabetes and a glycated hemoglobin level less than 5.7%, the primary outcome occurred in 53 of 438 patients (12.1%) in the dapagliflozin group and 71 of 419 (16.9%) in the placebo group (hazard ratio, 0.67 [95% CI, 0.47-0.96]). In patients with a glycated hemoglobin of at least 5.7%, the primary outcome occurred in 118 of 860 patients (13.7%) in the dapagliflozin group and 160 of 888 (18.0%) in the placebo group (hazard ratio, 0.74 [95% CI, 0.59-0.94]) (P value for interaction = .72). Volume depletion was reported as an adverse event in 7.3% of patients in the dapagliflozin group and 6.1% in the placebo group among patients without diabetes and in 7.8% of patients in the dapagliflozin group and 7.8% in the placebo group among patients with diabetes. A kidney adverse event was reported in 4.8% of patients in the dapagliflozin group and 6.0% in the placebo group among patients without diabetes and in 8.5% of patients in the dapagliflozin group and 8.7% in the placebo group among patients with diabetes. Conclusions and Relevance: In this exploratory analysis of a randomized trial of patients with HFrEF, dapagliflozin compared with placebo, when added to recommended therapy, significantly reduced the risk of worsening heart failure or cardiovascular death independently of diabetes status. Trial Registration: ClinicalTrials.gov Identifier: NCT03036124.

2.
Cardiovasc Drugs Ther ; 34(1): 79-88, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32076931

RESUMO

PURPOSE: Although impaired glucose tolerance (IGT) promotes cardiovascular events, our Alpha-glucosidase-inhibitor Blocks Cardiac Events in Patients with Myocardial Infarction and Impaired Glucose Tolerance (ABC) study showed that alpha-glucosidase inhibitors do not prevent cardiovascular events in patients with myocardial infarction (MI) and IGT. The aim of the present study was to identify potential clinical factors for cardiovascular events in patients with MI and IGT. METHODS: Using the limitless-arity multiple testing procedure, an artificial intelligence (AI)-based data mining method, we analyzed 385,391 combinations of fewer than four clinical parameters. RESULTS: We identified 380 combinations predicting the occurrence of (1) all-cause hospitalization, (2) hospitalization due to worsening of heart failure (HF), (3) hospitalization due to non-fatal MI, and (4) hospitalization due to percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG) for stable angina among 385,391 combinations in 853 patients. Among these, either plasma BNP levels ≥ 200 pg/dl or diuretic use exclusively predicted (1) all-cause hospitalization, (2) hospitalization due to worsening of HF, and (3) hospitalization due to a non-fatal MI, with plasma BNP levels ≥ 200 pg/dl being the sole predictor of hospitalization due to PCI and CABG. Importantly, each finding was verified by independently drawn Kaplan-Meier curves, revealing the unexpected role of plasma BNP levels in the progression of coronary stenosis determined as the necessity of PCI and CABG for stable angina. CONCLUSIONS: In patients with MI and IGT, high plasma BNP levels predicted the occurrence of coronary stenosis, recurrent MI, and worsening of HF, whereas diuretic use did not predict the progression of coronary stenosis but non-fatal MI and worsening of HF.

3.
Circ J ; 84(3): 384-385, 2020 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-32062637
4.
FASEB J ; 34(2): 2041-2054, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31916304

RESUMO

Most eukaryotic cells generate adenosine triphosphate (ATP) through the oxidative phosphorylation system (OXPHOS) to support cellular activities. In cultured cell-based experiments, we recently identified the hypoxia-inducible protein G0/G1 switch gene 2 (G0s2) as a positive regulator of OXPHOS, and showed that G0s2 protects cultured cardiomyocytes from hypoxia. In this study, we examined the in vivo protective role of G0s2 against hypoxia by generating both loss-of-function and gain-of-function models of g0s2 in zebrafish. Zebrafish harboring transcription activator-like effector nuclease (TALEN)-mediated knockout of g0s2 lost hypoxic tolerance. Conversely, cardiomyocyte-specific transgenic zebrafish hearts exhibited strong tolerance against hypoxia. To clarify the mechanism by which G0s2 protects cardiac function under hypoxia, we introduced a mitochondrially targeted FRET-based ATP biosensor into zebrafish heart to visualize ATP dynamics in in vivo beating hearts. In addition, we employed a mosaic overexpression model of g0s2 to compare the contraction and ATP dynamics between g0s2-expressing and non-expressing cardiomyocytes, side-by-side within the same heart. These techniques revealed that g0s2-expressing cardiomyocyte populations exhibited preserved contractility coupled with maintained intra-mitochondrial ATP concentrations even under hypoxic condition. Collectively, these results demonstrate that G0s2 provides ischemic tolerance in vivo by maintaining ATP production, and therefore represents a promising therapeutic target for hypoxia-related diseases.

5.
Lab Invest ; 100(2): 324-337, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31896817

RESUMO

Abnormal Ca2+ handling is essential in the pathophysiology of degenerative muscle disorders, such as dilated cardiomyopathy (DCM) and muscular dystrophy (MD). Transient receptor potential cation channel, subfamily V, member 2 (TRPV2) is a candidate for Ca2+ entry and a potential therapeutic target for degenerative muscle disorders, there are few specific inhibitors for TRPV2. In this study, we produced a monoclonal antibody (designated mAb88-2) and two polyclonal antibodies (pAb591 and pAb592) that selectively recognize TRPV2 from the outside of cells and interact with the turret region of the pore-forming outer gate. These antibodies inhibited Ca2+ influx via TRPV2 in cultured cells and substantially reduced TRPV2 in the plasma membrane via cellular internalization. We evaluated the therapeutic efficacy of the functional antibody in δ-sarcoglycan-deficient hamster (J2N-k) models of DCM and MD and in the 4C30 DCM model of murine heart failure. The intraperitoneal administration of the functional antibody (0.5 mg/kg) for 2 weeks (once a week) prevented the progression of cardiac dysfunction, as evaluated by echocardiography and histological staining, and improved the abnormal Ca2+ handling (high diastolic Ca2+ level and small Ca2+ transient peak) in cardiomyocytes isolated from J2N-k hamsters and prevented skeletal muscle damage. Further, the antibody effectively prevented heart failure in the 4C30 mouse model with end-stage DCM. Interestingly, endogenous TRPV2 that accumulated in the cardiac and skeletal muscle sarcolemma disappeared upon antibody administration. Thus, the newly produced antibodies are capable of ameliorating DCM and MD by promoting the cellular internalization of TRPV2; antibodies specific to human TRPV2 may substantially improve the treatment of patients with degenerative muscle diseases.

6.
Circulation ; 141(2): 90-99, 2020 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-31736335

RESUMO

BACKGROUND: Goals of management in patients with heart failure and reduced ejection fraction include reducing death and hospitalizations, and improving health status (symptoms, physical function, and quality of life). In the DAPA-HF trial (Dapagliflozin and Prevention of Adverse-Outcomes in Heart Failure), sodium-glucose cotransporter-2 inhibitor, dapagliflozin, reduced death and hospitalizations, and improved symptoms in patients with heart failure and reduced ejection fraction. In this analysis, we examine the effects of dapagliflozin on a broad range of health status outcomes, using the Kansas City Cardiomyopathy Questionnaire (KCCQ). METHODS: KCCQ was evaluated at randomization, 4 and 8 months. Patients were divided by baseline KCCQ total symptom score (TSS); Cox proportional hazards models examined the effects of dapagliflozin on clinical events across these subgroups. We also evaluated the effects of dapagliflozin on KCCQ-TSS, clinical summary score, and overall summary score. Responder analyses were performed to compare proportions of dapagliflozin versus placebo-treated patients with clinically meaningful changes in KCCQ at 8 months. RESULTS: A total of 4443 patients had available KCCQ at baseline (median KCCQ-TSS, 77.1 [interquartile range, 58.3-91.7]). The effects of dapagliflozin vs placebo on reducing cardiovascular death or worsening heart failure were consistent across the range of KCCQ-TSS (lowest to highest tertile: hazard ratio, 0.70 [95% CI, 0.57-0.86]; hazard ratio, 0.77 [95% CI, 0.61-0.98]; hazard ratio, 0.62 [95% CI, 0.46-0.83]; P for heterogeneity=0.52). Patients treated with dapagliflozin had greater improvement in mean KCCQ-TSS, clinical summary score, and overall summary score at 8 months (2.8, 2.5 and 2.3 points higher versus placebo; P<0.0001 for all). Fewer patients treated with dapagliflozin had a deterioration in KCCQ-TSS (odds ratio, 0.84 [95% CI, 0.78-0.90]; P<0.0001); and more patients had at least small, moderate, and large improvements (odds ratio, 1.15 [95% CI, 1.08-1.23]; odds ratio, 1.15 [95% CI, 1.08-1.22]; odds ratio, 1.14 [95% CI, 1.07-1.22]; number needed to treat=14, 15, and 18, respectively; P<0.0001 for all; results consistent for KCCQ clinical summary score and overall summary score). CONCLUSIONS: Dapagliflozin reduced cardiovascular death and worsening heart failure across the range of baseline KCCQ, and improved symptoms, physical function, and quality of life in patients with heart failure and reduced ejection fraction. Furthermore, dapagliflozin increased the proportion of patients experiencing at least small, moderate, and large improvements in health status; these effects were clinically important. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov. Unique identifier: NCT03036124.

7.
Biochim Biophys Acta Mol Basis Dis ; 1866(3): 165623, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31778748

RESUMO

The role of the cardiac isoform of the electrogenic sodium-bicarbonate ion cotransporter (NBCe1) in cardiac remodeling is not fully understood. The aim of this study was to assess the effects of NBCe1 overexpression on cardiac remodeling induced by myocardial infarction (MI) in mice. We generated NBCe1 transgenic (Tg) mice and NBCe1 overexpressing adult mouse ventricular myocytes (AMVMs) to investigate the role of NBCe1 on post-MI remodeling and calcium kinetics. Tg mice showed a markedly higher mortality rate and larger infarct size after MI. At 6 weeks after MI, the maximum rising rates of left ventricular pressure (dp/dt), contractility index, and the exponential time constant of relaxation (τ) were markedly lower, and there was higher cardiomyocyte apoptosis, in Tg mice compared with WT mice. In cultured AMVMs, overexpression of NBCe1 decreased sarcomere shortening and calcium amplitude. In WT AMVMs, the rates of the rise and decay phase of calcium transients, indicated by the rising time (Tpeak, time to peak) and decay time constant (τd), and the number of apoptotic cells, were increased following hypoxia, while overexpression of NBCe1 further increased Tpeak and cellular apoptosis, but not τd. Intracellular resting calcium and sodium concentrations were significantly increased following both hypoxia and NBCe1 overexpression. Co-treatment with S0859, an NBCe1 antagonist, blocked the hypoxia-induced increase in Tpeak, τd, intracellular resting calcium and sodium concentrations, and apoptosis in cardiomyocytes. These findings indicate that NBCe1 overexpression promotes cardiac remodeling by increasing intracellular calcium overload. Therefore, NBCe1 should be a potential target for treatment of cardiac remodeling.

8.
J Cardiol ; 75(4): 439-446, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31813675

RESUMO

BACKGROUND: Left ventricular (LV) hypertrophy is reported to cause LV diastolic dysfunction. This study aimed to examine the prevalence of LV diastolic dysfunction in each group categorized by the geometric pattern of LV hypertrophy in a community-based population. METHODS: We studied 1260 community-dwelling subjects who experienced no symptoms of obvious heart disease (461 men, 799 women) and who participated in annual health check-ups in a rural Japanese community. The subjects were divided into 4 groups according to LV mass index and relative wall thickness: normal geometry, concentric remodeling, eccentric hypertrophy, and concentric hypertrophy. We investigated the prevalence of LV diastolic dysfunction in the overall and stratified population by LV geometric pattern. LV diastolic function was determined by 3 echocardiographic parameters of LV diastolic function: early diastolic myocardial velocity, the ratio of early diastolic mitral inflow velocity and myocardial velocity, and indexed left atrial dimension. LV diastolic dysfunction was defined as the presence of abnormal values in more than 2 of 3 echocardiographic parameters. RESULTS: The prevalence of LV diastolic dysfunction was higher in the categories with more severe LV hypertrophy. However, LV mass index, rather than relative wall thickness, was a significant determinant of LV diastolic dysfunction, after adjustment for comorbidities. In addition, 71 (10%) out of 740 subjects with normal LV geometric pattern had LV diastolic dysfunction even without obvious LV geometric change. CONCLUSIONS: The prevalence of LV diastolic dysfunction was higher in the subjects with more severe LV hypertrophy in a community-based population. Subclinical LV diastolic dysfunction without obvious LV geometric change should be noted and its clinical impact should be elucidated.

9.
Cardiovasc Res ; 116(1): 101-113, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30689763

RESUMO

AIMS: Proton pump inhibitors (PPIs) are widely used in patients receiving percutaneous coronary intervention to prevent gastric bleeding, but whether PPIs are beneficial for the heart is controversial. Here, we investigated the effects of lansoprazole on cardiac hypertrophy and heart failure, as well as the underlying mechanisms. METHODS AND RESULTS: Adult male C57 mice were subjected to transverse aortic constriction (TAC) or sham surgery and then were treated with lansoprazole or vehicle for 5 weeks. In addition, cultured neonatal rat ventricular cardiomyocytes and fibroblasts were exposed to angiotensin II in the presence or absence of lansoprazole. At 5 weeks after TAC, the heart weight/body weight ratio was lower in lansoprazole-treated mice than in untreated mice, as was the lung weight/body weight ratio, while left ventricular (LV) fractional shortening and the maximum and minimum rates of change of the LV pressure were higher in lansoprazole-treated mice, along with less cardiac fibrosis. In cultured cardiomyocytes, lansoprazole inhibited angiotensin II-induced protein synthesis and hypertrophy, as well as inhibiting proliferation of fibroblasts. Lansoprazole decreased myocardial levels of phosphorylated Akt, phosphorylated glycogen synthase kinase 3ß, and active ß-catenin in TAC mice and in angiotensin II-stimulated cardiomyocytes. After overexpression of active ß-catenin or knockdown of H+/K+-ATPase α-subunit, lansoprazole still significantly attenuated myocyte hypertrophy. CONCLUSION: Lansoprazole inhibits cardiac remodelling by suppressing activation of the Akt/GSK3ß/ß-catenin pathway independent of H+/K+-ATPase inhibition, and these findings may provide a novel insight into the pharmacological effects of PPIs with regard to alleviation of cardiac remodelling.

10.
Lab Invest ; 100(2): 207-217, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31857697

RESUMO

Heart transplantation is currently the only viable option available for the treatment of severe heart failure conditions such as dilated cardiomyopathy. Hence, novel drugs for treating such conditions need to be developed urgently. Recent studies suggest that Ca2+ overload is involved in the onset and progression of dilated cardiomyopathy, and thus heart failure. The expression and activation of the Ca2+ permeable channel, transient receptor potential vanilloid 2 (TRPV2) channel have been found to play an essential role in sustained intracellular Ca2+ concentration increase, leading to heart failure. However, since there have been no TRPV2-specific inhibitors available until recently, the effect of TRPV2 inhibition on the pathology has not been clearly elucidated. Recent reports show that inhibiting TRPV2 activity effectively improves cardiac function, suppressing myocardial fibrosis and ameliorating the prognosis in animal models of cardiomyopathy with heart failure. In addition to that, inflammation is reported to be involved in the development of heart failure. Here, we review the recent findings on TRPV2 in cardiomyocytes and immune cells involved in the development of heart failure and discuss the current progress of drug development for the treatment of heart failure via targeting TRPV2.

11.
Heart Vessels ; 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31686125

RESUMO

Physical activity (PA) in the daily life is strongly related to prognosis in patients with or at high risk of heart failure (HF). However, factors limiting habitual exercise and their prognostic impacts remain unknown in HF patients. We sent questionnaires asking factors limiting habitual exercise in the daily life to 8370 patients with Stage A/B/C/D HF in our nationwide registry and received valid responses from 4935 patients (mean age 71.8 years, 71.0% male). Among the 5 components consisting of "busyness", "weak will", "dislike, "socioeconomic reasons" and "diseases" in the questionnaires, "busyness" (34.5%) and "diseases" (34.7%) were the most frequently reported factors limiting habitual exercise, while "socioeconomic reasons" were the least (15.3%). Multiple Cox proportional hazard models indicated that "busyness"and "diseases" were associated with better (hazard ratio (HR) 0.53, 95% confidence interval (CI) 0.39-0.72, P < 0.001) and worse prognosis (HR 1.57, 95% CI 1.21-1.98, P < 0.001), respectively, while other components were not. Furthermore, it was noted that, while prognostic relevance of "busyness" limiting exercise did not differ by age or sex, negative impact of "diseases" was particularly evident in patients with age < 75 years (P for interaction < 0.01). Factors limiting habitual exercise were associated with "busyness" and "diseases", but not with "weak will", "dislike, or "socioeconomic reasons". While "busyness" was associated with better prognosis regardless of age and sex, "diseases" was associated with worse prognosis in younger populations. Thus, physicians may pay more attentions to the reasons that limit exercise in the daily lives of HF patients rather than the low amount of exercise itself.

13.
N Engl J Med ; 381(21): 1995-2008, 2019 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-31535829

RESUMO

BACKGROUND: In patients with type 2 diabetes, inhibitors of sodium-glucose cotransporter 2 (SGLT2) reduce the risk of a first hospitalization for heart failure, possibly through glucose-independent mechanisms. More data are needed regarding the effects of SGLT2 inhibitors in patients with established heart failure and a reduced ejection fraction, regardless of the presence or absence of type 2 diabetes. METHODS: In this phase 3, placebo-controlled trial, we randomly assigned 4744 patients with New York Heart Association class II, III, or IV heart failure and an ejection fraction of 40% or less to receive either dapagliflozin (at a dose of 10 mg once daily) or placebo, in addition to recommended therapy. The primary outcome was a composite of worsening heart failure (hospitalization or an urgent visit resulting in intravenous therapy for heart failure) or cardiovascular death. RESULTS: Over a median of 18.2 months, the primary outcome occurred in 386 of 2373 patients (16.3%) in the dapagliflozin group and in 502 of 2371 patients (21.2%) in the placebo group (hazard ratio, 0.74; 95% confidence interval [CI], 0.65 to 0.85; P<0.001). A first worsening heart failure event occurred in 237 patients (10.0%) in the dapagliflozin group and in 326 patients (13.7%) in the placebo group (hazard ratio, 0.70; 95% CI, 0.59 to 0.83). Death from cardiovascular causes occurred in 227 patients (9.6%) in the dapagliflozin group and in 273 patients (11.5%) in the placebo group (hazard ratio, 0.82; 95% CI, 0.69 to 0.98); 276 patients (11.6%) and 329 patients (13.9%), respectively, died from any cause (hazard ratio, 0.83; 95% CI, 0.71 to 0.97). Findings in patients with diabetes were similar to those in patients without diabetes. The frequency of adverse events related to volume depletion, renal dysfunction, and hypoglycemia did not differ between treatment groups. CONCLUSIONS: Among patients with heart failure and a reduced ejection fraction, the risk of worsening heart failure or death from cardiovascular causes was lower among those who received dapagliflozin than among those who received placebo, regardless of the presence or absence of diabetes. (Funded by AstraZeneca; DAPA-HF ClinicalTrials.gov number, NCT03036124.).


Assuntos
Compostos Benzidrílicos/uso terapêutico , Glucosídeos/uso terapêutico , Insuficiência Cardíaca/tratamento farmacológico , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Idoso , Compostos Benzidrílicos/efeitos adversos , Fármacos Cardiovasculares/uso terapêutico , Doenças Cardiovasculares/mortalidade , Terapia Combinada , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Quimioterapia Combinada , Feminino , Glucosídeos/efeitos adversos , Hemoglobina A Glicada/análise , Insuficiência Cardíaca/complicações , Hospitalização , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Inibidores do Transportador 2 de Sódio-Glicose/efeitos adversos , Volume Sistólico/efeitos dos fármacos , Disfunção Ventricular Esquerda/complicações , Disfunção Ventricular Esquerda/tratamento farmacológico
15.
Int J Cardiol Heart Vasc ; 24: 100396, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31334333

RESUMO

Background: Endogenous adenosine levels increase under stress in various organs. Exogenously administered adenosine is a well-known pulmonary vasodilator. However, the physiology and therapeutic potential of endogenous adenosine during alteration in pulmonary hemodynamics such as pulmonary embolism is not elucidated. We hypothesized that the adenosine level increases following an acute elevation of pulmonary resistance, resulting in pulmonary vasodilation. Methods: We induced acute pulmonary embolization by injecting plastic beads in anesthetized dogs. Plasma adenosine levels, defined as the product of plasma adenosine concentration and simultaneous cardiac output, were assessed from blood samples from the superior vena cava, main pulmonary artery (MPA), and ascending aorta 1 and 10 min following injection. Hemodynamics were assessed with (n = 3) and without (n = 8) administration of the adenosine receptor blocker, 8-(p-sulfophenyl)theophylline (8SPT). Results: Mean pulmonary arterial pressure (PAP) increased from 11 ±â€¯1 mmHg, peaking at 28 ±â€¯4 mmHg at 52 ±â€¯13 s after injection. During this period, total pulmonary resistance (TPR) elevated from 11 ±â€¯1 to 33 ±â€¯6 Wood unit. Plasma adenosine levels increased in the MPA from 14.5 ±â€¯2 to 38.8 ±â€¯7 nmol/min 1 min after injection. TPR showed greater elevation under 8SPT treatment, to 96 ±â€¯12 Wood unit at PAP peak. Conclusions: Endogenously released adenosine after acute pulmonary embolization is one of the initial pulmonary vasodilators. The immediate surge in plasma adenosine levels in the MPA could lead to a hypothesis that adenosine is released by the right heart in response to pressure overload.

16.
Hypertens Res ; 42(11): 1716-1725, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31209398

RESUMO

Beta-blockers are recommended as a standard therapy for patients with heart failure (HF). However, beta-blockers are reportedly less effective in HF patients with atrial fibrillation (Af) compared with those with sinus rhythm (SR). Here, we investigated whether HR at discharge determined the cardiovascular outcomes in HF patients with Af treated with beta-blockers. In this analysis, we enrolled 97 HF patients with concomitant Af. These patients were divided into 6 groups according to beta-blocker use and tertiles of discharge HR: lowest <60 beats per minute (bpm), middle 61-70 bpm and highest >71 bpm. The primary endpoint was defined as a composite of rehospitalization due to worsening of HF and all-cause mortality. During a median follow-up of 772 days after discharge, the composite cardiovascular outcome occurred in 37 (61%) and 25 (69%) patients with or without beta-blockers, respectively. In the Cox proportional hazard analysis, the lowest HR tertile in patients with beta-blockers was associated with an increased risk of the composite outcome compared with the middle and highest tertiles in both the unadjusted model (hazard ratio: 2.568, 95% confidence interval (CI): 1.089-6.057, p = 0.031; hazard ratio: 2.024, 95% CI: 0.921-4.447, p = 0.079, respectively) and the model adjusted for potential confounders (hazard ratio: 2.631, 95% CI: 1.078-6.421, p = 0.034; hazard ratio: 2.876, 95% CI: 1.147-7.207, p = 0.024, respectively). In patients with HF and Af receiving beta-blockers, low HR adversely increased the risk of cardiovascular events. This fact may blunt the beneficial effects of beta-blockers in patients with HF and Af.

17.
Cardiovasc Drugs Ther ; 33(3): 363-370, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30850916

RESUMO

BACKGROUND AND AIMS: Diabetes mellitus (DM) can cause left ventricular (LV) diastolic dysfunction, leading to heart failure with preserved ejection fraction (HFpEF). Dipeptidyl peptidase IV (DPP-IV) inhibitors have failed to reduce hospitalization due to HF in type 2 DM (T2D) patients in a large-scale clinical trial, despite their cardiovascular protective effects. Therefore, it is important to investigate whether DPP-IV inhibitors can improve LV diastolic dysfunction in T2D patients. The aim of the study was to evaluate whether teneligliptin, the strongest of the DPP-IV inhibitors, improves LV dysfunction or prevents the worsening of LV diastolic function in T2D patients. METHODS: The TOPLEVEL study is designed as an open-labeled, marker-stratified randomized, parallel-group comparison, standard treatment-controlled multicenter study. TOPLEVEL includes two marker-defined subgroups to give treatment recommendations for T2D patients with normal (E/e' < 8) or impaired LV diastolic function (E/e' ≥ 8), where E/e' is the ratio of peak velocity of early transmitral diastolic filling by echocardiography to early diastolic mitral annular velocity by tissue Doppler echocardiography as LV diastolic function. Patients are randomly assigned to either teneligliptin (20 or 40 mg) or the standard treatment group. All patients are followed up for 2 years. The primary endpoint measure is the change in E/e' from baseline and 2 years after enrollment. CONCLUSION AND PERSPECTIVES: TOPLEVEL is a clinical trial of teneligliptin targeting LV diastolic dysfunction in T2D patients. This study demonstrates the effectiveness of DPP-IV inhibitors on LV diastolic dysfunction, an important surrogate endpoint to predict the cardiovascular outcomes of HFpEF (UMIN000014589).

18.
Cardiovasc Drugs Ther ; 33(3): 277-286, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30903544

RESUMO

PURPOSE: Several lines of evidence suggest that renal dysfunction is associated with cardiovascular toxicity through the action of uremic toxins. The levels of those uremic toxins can be reportedly reduced by the spherical carbon adsorbent AST-120. Because heart failure (HF) causes renal dysfunction by low cardiac output and renal edema, the removal of uremic toxins could be cardioprotective. METHOD: To determine whether blood levels of the uremic toxin indoxyl sulfate (IS) increase in HF and whether AST-120 can reduce those levels and improve HF. We induced HF in 12 beagle dogs by 6 weeks of rapid right ventricular pacing at 230 beats per min. We treated six dogs with a 1-g/kg/day oral dosage of AST-120 for 14 days from week 4 after the start of rapid ventricular pacing. The other six dogs did not receive any treatment (control group). RESULTS: In the untreated dogs, IS levels increased as cardiac function deteriorated. In contrast, plasma IS levels in the treated dogs decreased to baseline levels, with both left ventricular fractional shortening and pulmonary capillary wedge pressure also improving when compared with untreated dogs. Finally, AST-120 treatment was shown to reduce both myocardial apoptosis and fibrosis along with decreases in extracellular signal-regulated kinase phosphorylation, the Bax/Bcl-2 ratio, and TGF-ß1 expression and increases in AKT phosphorylation. CONCLUSIONS: IS levels are increased in HF. AST-120 treatment reduces the levels of IS and improves the pathophysiology of HF in a canine model. AST-120 could be a novel candidate for the treatment of HF.

19.
J Mol Cell Cardiol ; 129: 257-265, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30880253

RESUMO

To date, there is no established treatment for heart failure with preserved ejection fraction (HFpEF). Dipeptidyl peptidase-IV (DPP-IV) inhibitors reportedly have improved not only diabetes mellitus but also heart failure with systolic dysfunction in experimental models. We investigated the effects of a DPP-IV inhibitor on HFpEF in rats. Dahl salt-sensitive rats were fed either high-salt (high-salt diet (HSD): 8% NaCl) or low-salt diets (0.3% NaCl) from 6.5 weeks of age. They were then treated with or without a DPP-IV inhibitor, vildagliptin (10 mg/kg/day, orally), from 11 weeks of age for 9 weeks and analyzed at the age of 20 weeks. HSD rats mimicked the pathophysiology of HFpEF. There were no differences in heart rate, blood pressure, left ventricular (LV) systolic function, or the extent of LV hypertrophy between HSD rats with or without vildagliptin. However, vildagliptin decreased LV end-diastolic pressure, the most reliable hemodynamic parameter of HFpEF in HSD rats. Vildagliptin also decreased the LV distensibility index, a sensitive marker of LV diastolic function in HSD rats. Vildagliptin decreased the expression of collagen genes in HSD hearts and attenuated LV interstitial fibrosis (HSD with vehicle and vildagliptin, 2.9% vs. 1.9%; P < 0.05). Furthermore, vildagliptin administration reduced both plasma renin activity and aldosterone concentrations in HSD rats. A DPP-IV inhibitor, vildagliptin, improved the severity of LV fibrosis, and thus, diastolic dysfunction of HFpEF in Dahl salt-sensitive hypertensive rats. DPP-IV inhibitors are promising medicines for treatment of HFpEF in patients with diabetes mellitus.

20.
Circulation ; 139(18): 2157-2169, 2019 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-30764634

RESUMO

BACKGROUND: Bradyarrhythmia is a common clinical manifestation. Although the majority of cases are acquired, genetic analysis of families with bradyarrhythmia has identified a growing number of causative gene mutations. Because the only ultimate treatment for symptomatic bradyarrhythmia has been invasive surgical implantation of a pacemaker, the discovery of novel therapeutic molecular targets is necessary to improve prognosis and quality of life. METHODS: We investigated a family containing 7 individuals with autosomal dominant bradyarrhythmias of sinus node dysfunction, atrial fibrillation with slow ventricular response, and atrioventricular block. To identify the causative mutation, we conducted the family-based whole exome sequencing and genome-wide linkage analysis. We characterized the mutation-related mechanisms based on the pathophysiology in vitro. After generating a transgenic animal model to confirm the human phenotypes of bradyarrhythmia, we also evaluated the efficacy of a newly identified molecular-targeted compound to upregulate heart rate in bradyarrhythmias by using the animal model. RESULTS: We identified one heterozygous mutation, KCNJ3 c.247A>C, p.N83H, as a novel cause of hereditary bradyarrhythmias in this family. KCNJ3 encodes the inwardly rectifying potassium channel Kir3.1, which combines with Kir3.4 (encoded by KCNJ5) to form the acetylcholine-activated potassium channel ( IKACh channel) with specific expression in the atrium. An additional study using a genome cohort of 2185 patients with sporadic atrial fibrillation revealed another 5 rare mutations in KCNJ3 and KCNJ5, suggesting the relevance of both genes to these arrhythmias. Cellular electrophysiological studies revealed that the KCNJ3 p.N83H mutation caused a gain of IKACh channel function by increasing the basal current, even in the absence of m2 muscarinic receptor stimulation. We generated transgenic zebrafish expressing mutant human KCNJ3 in the atrium specifically. It is interesting to note that the selective IKACh channel blocker NIP-151 repressed the increased current and improved bradyarrhythmia phenotypes in the mutant zebrafish. CONCLUSIONS: The IKACh channel is associated with the pathophysiology of bradyarrhythmia and atrial fibrillation, and the mutant IKACh channel ( KCNJ3 p.N83H) can be effectively inhibited by NIP-151, a selective IKACh channel blocker. Thus, the IKACh channel might be considered to be a suitable pharmacological target for patients who have bradyarrhythmia with a gain-of-function mutation in the IKACh channel.


Assuntos
Fibrilação Atrial , Bloqueio Atrioventricular , Bradicardia , Canais de Potássio Corretores do Fluxo de Internalização Acoplados a Proteínas G , Doenças Genéticas Inatas , Mutação de Sentido Incorreto , Substituição de Aminoácidos , Animais , Animais Geneticamente Modificados , Fibrilação Atrial/genética , Fibrilação Atrial/metabolismo , Fibrilação Atrial/patologia , Fibrilação Atrial/fisiopatologia , Bloqueio Atrioventricular/genética , Bloqueio Atrioventricular/metabolismo , Bloqueio Atrioventricular/patologia , Bloqueio Atrioventricular/fisiopatologia , Benzopiranos/farmacologia , Bradicardia/genética , Bradicardia/metabolismo , Bradicardia/patologia , Bradicardia/fisiopatologia , Técnicas Eletrofisiológicas Cardíacas , Feminino , Canais de Potássio Corretores do Fluxo de Internalização Acoplados a Proteínas G/antagonistas & inibidores , Canais de Potássio Corretores do Fluxo de Internalização Acoplados a Proteínas G/genética , Canais de Potássio Corretores do Fluxo de Internalização Acoplados a Proteínas G/metabolismo , Doenças Genéticas Inatas/genética , Doenças Genéticas Inatas/metabolismo , Doenças Genéticas Inatas/patologia , Doenças Genéticas Inatas/fisiopatologia , Humanos , Masculino , Xenopus laevis , Peixe-Zebra
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