P6276Impact of the cardiac specific deletion of AMPKalpha2 on the contractile and metabolic phenotype of the heart in male and female mice

2019 ◽  
Vol 40 (Supplement_1) ◽  
Author(s):  
L Grimbert ◽  
M N Sanz ◽  
C Rucker-Martin ◽  
M Novotova ◽  
M Gressette ◽  
...  

Abstract Introduction Mitochondrial dysfunction plays a major role in the Heart Failure (HF) pathophysiology.The AMP activated protein kinase (AMPK) is activated by a high AMP-ADP/ATP ratio and regulates a number of metabolic pathways. Many studies have highlighted a protective role of AMPK in HF, but its relevance to cardiac tissue, its metabolic part and its sex specificity are not well established. Purpose Then, the aim of this study is to determine the role of AMPK in the healthy and failing heart in male and female mice. Methods We developed and validated a mouse strain with an adult-inducible cardiac-specific deletion of AMPKα2, the major cardiac isoform, using the Cre-Lox system (40mg/kg tamoxifen injection on two consecutive days at adult age). At four months after the deletion, cardiac contractility, morphology and metabolism were studied in control and KO mice from both sexes. Results We observed only in male KO mice a decrease of left ventricular ejection fraction (−10%), an increase of the total fibrosis (+64%) and defects in mitochondrial structures. Male KO mice also showed a reduced (−28%) mitochondrial respiration via complex I associated with a different cardiolipin species distribution. Conclusion Our results reveal in adult healthy hearts, a sex-specificity in the effects of AMPKα2 deletion, leading to impaired contractile function related to metabolic and non-metabolic alterations only in male mice.

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
B.M.L Rocha ◽  
G.J Lopes Da Cunha ◽  
P.M.D Lopes ◽  
P.N Freitas ◽  
F Gama ◽  
...  

Abstract Background Cardiopulmonary exercise testing (CPET) is recommended in the evaluation of selected patients with Heart Failure (HF). Notwithstanding, its prognostic significance has mainly been ascertained in those with left ventricular ejection fraction (LVEF) <40% (i.e., HFrEF). The main goal of our study was to assess the role of CPET in risk stratification of HF with mid-range (40–49%) LVEF (i.e., HFmrEF) compared to HFrEF. Methods We conducted a single-center retrospective study of consecutive patients with HF and LVEF <50% who underwent CPET from 2003–2018. The primary composite endpoint of death, heart transplant or HF hospitalization was assessed. Results Overall, 404 HF patients (mean age 57±11 years, 78.2% male, 55.4% ischemic HF) were included, of whom 321 (79.5%) had HFrEF and 83 (20.5%) HFmrEF. Compared to the former, those with HFmrEF had a significantly higher mean peak oxygen uptake (pVO2) (20.2±6.1 vs 16.1±5.0 mL/kg/min; p<0.001), lower median minute ventilation/carbon dioxide production (VE/VCO2) [35.0 (IQR: 29.1–41.2) vs 39.0 (IQR: 32.0–47.0); p=0.002) and fewer patients with exercise oscillatory ventilation (EOV) (22.0 vs 46.3%; p<0.001). Over a median follow-up of 28.7 (IQR: 13.0–92.3) months, 117 (28.9%) patients died, 53 (13.1%) underwent heart transplantation, and 134 (33.2%) had at least one HF hospitalization. In both HFmrEF and HFrEF, pVO2 <12 mL/kg/min, VE/VCO2 >35 and EOV identified patients at higher risk for events (all p<0.05). In Cox regression multivariate analysis, pVO2 was predictive of the primary endpoint in both HFmrEF and HFrEF (HR per +1 mL/kg/min: 0.81; CI: 0.72–0.92; p=0.001; and HR per +1 mL/kg/min: 0.92; CI: 0.87–0.97; p=0.004), as was EOV (HR: 4.79; CI: 1.41–16.39; p=0.012; and HR: 2.15; CI: 1.51–3.07; p<0.001). VE/VCO2, on the other hand, was predictive of events in HFrEF but not in HFmrEF (HR per unit: 1.03; CI: 1.02–1.05; p<0.001; and HR per unit: 0.99; CI: 0.95–1.03; p=0.512, respectively). ROC curve analysis demonstrated that a pVO2 >16.7 and >15.8 mL/kg/min more accurately identified patients at lower risk for the primary endpoint (NPV: 91.2 and 60.5% for HFmrEF and HFrEF, respectively; both p<0.001). Conclusions CPET is a useful tool in HFmrEF. Both pVO2 and EOV independently predicted the primary endpoint in HFmrEF and HFrEF, contrasting with VE/VCO2, which remained predictive only in latter group. Our findings strengthen the prognostic role of CPET in HF with either reduced or mid-range LVEF. Funding Acknowledgement Type of funding source: None


2020 ◽  
Vol 72 (1) ◽  
Author(s):  
Ahmed Ayuna ◽  
Nik Abidin

Abstract Background Anthracycline-induced cardiotoxicity has been classified based on its onset into acute, early, and late. It may have a significant burden on the quality and quantity of life of those exposed to this class of medication. Currently, there are several ongoing debates on the role of different measures in the primary prevention of cardiotoxicity in cancer survivors. Our article aims to focus on the role of neurohormonal blockers in the primary prevention of anthracycline-induced cardiotoxicity, whether it is acute, early, or late onset. Main body of the abstract PubMed and Google Scholar database were searched for the relevant articles; we reviewed and appraised 15 RCTs, and we found that angiotensin-converting enzyme inhibitors (ACEI) and B-blockers were the most commonly used agents. Angiotensin II receptor blockers (ARBs) and mineralocorticoid receptor antagonists (MRAs) were used in a few other trials. The follow-up period was on the range of 1–156 weeks (mode 26 weeks). Left ventricular ejection fraction (LVEF), left ventricular diameters, and diastolic function were assessed by either echocardiogram or occasionally by cardiac magnetic resonance imaging (MRI). The occurrence of myocardial injury was assessed by troponin I. It was obvious that neurohormonal blockers reduced the occurrence of LVEF and myocardial injury in 14/15 RCTs. Short conclusion Beta-blockers, especially carvedilol and ACEI, especially enalapril, should be considered for the primary prevention of acute- and early-onset cardiotoxicity. ARB and MRA are suitable alternatives when patients are intolerant to ACE-I and B-blockers. We recommend further studies to explore and establish the role of neurohormonal blockers in the primary prevention of the acute-, early-, and late-onset cardiotoxicity.


2021 ◽  
Vol 102 (4) ◽  
pp. 510-517
Author(s):  
E V Khazova ◽  
O V Bulashova

The discussion continues about the role of systemic inflammation in the pathogenesis of cardiovascular diseases of ischemic etiology. This article reviews the information on the role of C-reactive protein in patients with atherosclerosis and heart failure in risk stratification for adverse cardiovascular events, including assessment of factors affecting the basal level of highly sensitive C-reactive protein. Research data (MRFIT, MONICA) have demonstrated a relationship between an increased level of C-reactive protein and the development of coronary heart disease. An increase in the serum level of highly sensitive C-reactive protein is observed in arterial hypertension, dyslipidemia, type 2 diabetes mellitus and insulin resistance, which indicates the involvement of systemic inflammation in these disorders. Currently, the assessment of highly sensitive C-reactive protein is used to determine the risk of developing myocardial infarction and stroke. It has been proven that heart failure patients have a high level of highly sensitive C-reactive protein compared with patients without heart failure. The level of C-reactive protein is referred to as modifiable risk factors for cardiovascular diseases of ischemic origin, since lifestyle changes or taking drugs such as statins, non-steroidal anti-inflammatory drugs, glucocorticoids, etc. reduce the level of highly sensitive C-reactive protein. In patients with heart failure with different left ventricular ejection fraction values, it was found that the regression of the inflammatory response is accompanied by an improvement in prognosis, which confirms the hypothesis of inflammation as a response to stress, which has negative consequences for the cardiovascular system.


2018 ◽  
Vol 47 (5) ◽  
pp. 361-371 ◽  
Author(s):  
Qing Kuang ◽  
Ning Xue ◽  
Jing Chen ◽  
Ziyan Shen ◽  
Xiaomeng Cui ◽  
...  

Background: Chronic kidney disease (CKD) has been proposed to associate with decreased hydrogen sulfide (H2S) level. Nevertheless, the role of H2S in the pathogenesis of CKD has not been fully investigated. Our study aimed to investigate the plasma level of endogenous H2S in patients with different stages of CKD, and to identify the role of H2S in the progression of CKD and its relationship with cardiovascular diseases. Methods: A total of 157 non-dialysis CKD patients were recruited in our study, with 37 age- and sex-matched healthy individuals as control. Plasma concentration of H2S was measured with spectrophotometry. Sulfhemoglobin, the integration of H2S and hemoglobin, was characterized and measured by dual wavelength spectrophotometry. Serum levels of homocysteine (Hcy), cardiac troponin T (cTnT), and N-terminal pro B type natriuretic peptide were measured using automated analyzers. Conventional transthoracic echocardiography was performed and left ventricular ejection fraction (LVEF) was analyzed as a sensitive parameter of cardiac dysfunction. Results: The plasma H2S level (μmol/L) in CKD patients was significantly lower than those in healthy controls (7.32 ± 4.02 vs. 14.11 ± 5.24 μmol/L, p < 0.01). Plasma H2S level was positively associated with estimated glomerular filtration rate (eGFR; ρ = 0.577, p < 0.01) and negatively associated with plasma indoxyl sulfate concentration (ρ = –0.554, p < 0.01). The mRNA levels of cystathionine β-synthase and cystathionine γ-lyase, 2 catalytic enzymes of H2S formation, were significantly lower in blood mononuclear cells of CKD patients with respect to controls; however, the mRNA level of 3-mercaptopyruvate sulfurtransferase, as another H2S-producing enzyme, was significantly higher in CKD patients. The serum concentration of Hcy, acting as the substrate of H2S synthetase, was higher in the CKD group (p < 0.01). Specifically, the content of serum Hcy in CKD stages 3–5 patients was significantly higher than that in CKD stages 1–2, indicating an increasing trend of serum Hcy with the decline of renal function. Examination of ultrasonic cardiogram revealed a negative ­correlation between plasma H2S level and LVEF (ρ = –0.204, p < 0.05) in CKD patients. The H2S level also correlated negatively with cTnT concentration (ρ = –0.249, p < 0.01). Conclusions: Plasma H2S level decreased with the decline of eGFR, which may contribute to the cardiac dysfunction in CKD ­patients.


2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
Y Wasserstrum ◽  
E Itelman ◽  
R Barriales-Villa ◽  
X Fernandez-Fernandez ◽  
Y Adler ◽  
...  

Abstract Background Advanced hypertrophic cardiomyopathy (HCM) may be complicated by a dilated hypokinetic transformation. Reduced left ventricular ejection fraction (HFrEF) has been described in terms of specific risks of morbidity and mortality, and specifically in terms of increased risk for fatal arrhythmias. Nevertheless, recent publications have casted doubt regarding the role of arrhythmia in non-ischemic HFrEF and questioned the role of primary prevention strategies in these cases. Methods We've reviewed clinical characteristics of 883 patients age ≥40, diagnosed with HCM who were evaluated in the cardiomyopathy clinic in two tertiary medical centers in Israel and Spain. Results Forty-five patients (5%) suffered from hypokinetic transformation. They were younger at diagnosis (median 32 [IQR 24–55] vs. 49 [35–60], p&lt;0.001), had a lower body-mass index (28.4 [±4.7] vs. 26.0 [±3.9], p&lt;0.001), and suffered more from strokes (19% vs 6%, p&lt;0.001). They had lower had a lower NYHA class (p=0.001) and lower exercise capacity (7.3 [4.5–10.8] vs. 9.6 [6.7–12.0] METS, p&lt;0.001). Patients with hypokinetic HCM had higher rates of pacemaker and implanted defibrillator (ICD) implantations (41% vs 11%, p&lt;0.001) and (43% vs 13%, p&lt;0.001) respectively. These patients had a higher incidence of sustained ventricular tachyarrhythmias (14% vs 2%, p&lt;0.001). Among patients who had an ICD, patients suffering from hypokinetic transformation had received more appropriate ICD therapy (27% vs 12%, p&lt;0.001). These patients received more heart transplantations (13% vs 1%, p&lt;0.001), and had a trend for higher incidence rate of Sudden cardiac death (6% vs 2% p=0.06) and a higher 5-year mortality rates (21% vs. 5%, p&lt;0.001). Conclusions HCM patients suffering from hypokinetic transformation have lower functional and exercise capacities, are more likely to suffer from ventricular tachyarrhythmias and experience appropriate ICD therapy, and undergo heart transplantation. They also have a significantly lower 5-year survival. Five-year survival Funding Acknowledgement Type of funding source: None


2020 ◽  
Author(s):  
Wendy Bottinor ◽  
Natalie Kelsey ◽  
Elizabeth C Riley ◽  
John Craycroft ◽  
Maiying Kong

ABSTRACT Background: Standard of care treatment for human epidermal growth factor receptor 2 (HER2) positive (HER2+) breast cancer often involves HER2 antagonism and anthracyclines. Anthracyclines and HER2 antagonists are associated with cardiotoxicity and cardiac screening is suggested. The optimal strategy for cardiac monitoring is not definitively established and the potential role of biomarkers to detect subclinical cardiotoxicity is an active area of interest within the field of cardio-oncology. Methods: This single center retrospective cohort analysis, examined the role of troponin I (Tp I) to detect subclinical cardiotoxicity and predict subsequent cardiovascular dysfunction in patients undergoing treatment for HER2+ breast cancer treated with combination trastuzumab and pertuzumab therapy. Subjects were identified by review of cardio-oncology and medical oncology clinical registries. Demographic and clinical data were obtained through chart review. Tp I absolute values and temporal trends, and subsequent decline in left ventricular ejection fraction or development of symptomatic heart failure were evaluated and compared for different chemotherapeutic regimens. Results: The incidence of Tp I elevation was significantly higher in patients treated with both anthracycline and HER2 antagonism when compared to patients treated with anthracycline or HER2 antagonism alone. In patients treated with both anthracycline and HER2 antagonism (either trastuzumab alone or in combination with pertuzumab), Tp I levels became positive (greater than 0.03 ng/mL) after the completion anthracycline therapy and 3.8 + 1.93 infusions of anti-HER2 therapy. The average peak Tp I was 0.104 + 0.05. Resolution of Tp I elevation occurred by infusion 14 + 1.94. Conclusions: Patients treated with a combination of anthracycline and HER2 antagonism, demonstrated elevated Tp I values with peak Tp I occurring after completion of anthracyclines and approximately 7 infusions of HER2 antagonist therapy.


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