Left ventricular ejection fraction (EF) remains the major parameter for diagnosis, phenotyping, prognosis and treatment decisions in heart failure. The 2016 ESC heart failure guidelines introduced a ...third EF category for an EF of 40-49%, defined as heart failure with mid-range EF (HFmrEF). This category has been largely unexplored compared with heart failure with reduced EF (HFrEF; defined as EF <40% in this Review) and heart failure with preserved EF (HFpEF; defined as EF ≥50%). The prevalence of HFmrEF within the overall population of patients with HF is 10-25%. HFmrEF seems to be an intermediate clinical entity between HFrEF and HFpEF in some respects, but more similar to HFrEF in others, in particular with regard to the high prevalence of ischaemic heart disease in these patients. HFmrEF is milder than HFrEF, and the risk of cardiovascular events is lower in patients with HFmrEF or HFpEF than in those with HFrEF. By contrast, the risk of non-cardiovascular adverse events is similar or greater in patients with HFmrEF or HFpEF than in those with HFrEF. Evidence from post hoc and subgroup analyses of randomized clinical trials and a trial of an SGLT1-SGLT2 inhibitor suggests that drugs that are effective in patients with HFrEF might also be effective in patients with HFmrEF. Although the EF is a continuous measure with considerable variability, in this comprehensive Review we suggest that HFmrEF is a useful categorization of patients with HF and shares the most important clinical features with HFrEF, which supports the renaming of HFmrEF to HF with mildly reduced EF.
Recent evidence indicates that a few human microRNAs (miRNAs), in particular hsa-miR-199a-3p and hsa-miR-590-3p, stimulate proliferation of cardiomyocytes and, once expressed in the mouse heart using ...viral vectors, induce cardiac regeneration after myocardial infarction. Viral vectors, however, are not devoid of safety issues and, more notably, drive expression of the encoded miRNAs for indefinite periods of time, which might not be desirable in light of human therapeutic application.
As an alternative to the use of viral vectors, we wanted to assess the efficacy of synthetic miRNA mimics in inducing myocardial repair after single intracardiac injection using synthetic lipid formulations.
We comparatively analyzed the efficacy of different lipid formulations in delivering hsa-miR-199a-3p and hsa-miR-590-3p both in primary neonatal mouse cardiomyocytes and in vivo. We established a transfection protocol allowing persistence of these 2 mimics for at least 12 days after a single intracardiac injection, with minimal dispersion to other organs and long-term preservation of miRNA functional activity, as assessed by monitoring the expression of 2 mRNA targets. Administration of this synthetic formulation immediately after myocardial infarction in mice resulted in marked reduction of infarct size and persistent recovery of cardiac function.
A single administration of synthetic miRNA-lipid formulations is sufficient to stimulate cardiac repair and restoration of cardiac function.
Evolving concepts in dilated cardiomyopathy Merlo, Marco; Cannatà, Antonio; Gobbo, Marco ...
European journal of heart failure,
February 2018, Letnik:
20, Številka:
2
Journal Article
Recenzirano
Odprti dostop
Dilated cardiomyopathy (DCM) represents a particular aetiology of systolic heart failure that frequently has a genetic background and usually affects young patients with few co‐morbidities. The ...prognosis of DCM has improved substantially during the last decades due to more accurate aetiological characterization, the red‐flag integrated approach to the disease, early diagnosis through systematic familial screening, and the concept of DCM as a dynamic disease requiring constant optimization of medical and non‐pharmacological evidence‐based treatments. However, some important issues in clinical management remain unresolved, including the role of cardiac magnetic resonance for diagnosis and risk categorization and the interaction between genotype and clinical phenotype, and arrhythmic risk stratification. This review offers a comprehensive survey of these and other emerging issues in the clinical management of DCM, providing where possible practical recommendations.
In mammals, enlargement of the heart during embryonic development is primarily dependent on the increase in cardiomyocyte numbers. Shortly after birth, however, cardiomyocytes stop proliferating and ...further growth of the myocardium occurs through hypertrophic enlargement of the existing myocytes. As a consequence of the minimal renewal of cardiomyocytes during adult life, repair of cardiac damage through myocardial regeneration is very limited. Here we show that the exogenous administration of selected microRNAs (miRNAs) markedly stimulates cardiomyocyte proliferation and promotes cardiac repair. We performed a high-content microscopy, high-throughput functional screening for human miRNAs that promoted neonatal cardiomyocyte proliferation using a whole-genome miRNA library. Forty miRNAs strongly increased both DNA synthesis and cytokinesis in neonatal mouse and rat cardiomyocytes. Two of these miRNAs (hsa-miR-590 and hsa-miR-199a) were further selected for testing and were shown to promote cell cycle re-entry of adult cardiomyocytes ex vivo and to promote cardiomyocyte proliferation in both neonatal and adult animals. After myocardial infarction in mice, these miRNAs stimulated marked cardiac regeneration and almost complete recovery of cardiac functional parameters. The miRNAs identified hold great promise for the treatment of cardiac pathologies consequent to cardiomyocyte loss.
Abstract
Aims
To evaluate the impact of the COVID-19 pandemic on patient admissions to Italian cardiac care units (CCUs).
Methods and Results
We conducted a multicentre, observational, nationwide ...survey to collect data on admissions for acute myocardial infarction (AMI) at Italian CCUs throughout a 1 week period during the COVID-19 outbreak, compared with the equivalent week in 2019. We observed a 48.4% reduction in admissions for AMI compared with the equivalent week in 2019 (P < 0.001). The reduction was significant for both ST-segment elevation myocardial infarction STEMI; 26.5%, 95% confidence interval (CI) 21.7–32.3; P = 0.009 and non-STEMI (NSTEMI; 65.1%, 95% CI 60.3–70.3; P < 0.001). Among STEMIs, the reduction was higher for women (41.2%; P = 0.011) than men (17.8%; P = 0.191). A similar reduction in AMI admissions was registered in North Italy (52.1%), Central Italy (59.3%), and South Italy (52.1%). The STEMI case fatality rate during the pandemic was substantially increased compared with 2019 risk ratio (RR) = 3.3, 95% CI 1.7–6.6; P < 0.001. A parallel increase in complications was also registered (RR = 1.8, 95% CI 1.1–2.8; P = 0.009).
Conclusion
Admissions for AMI were significantly reduced during the COVID-19 pandemic across Italy, with a parallel increase in fatality and complication rates. This constitutes a serious social issue, demanding attention by the scientific and healthcare communities and public regulatory agencies.
Aims
An algorithm for non‐invasive diagnosis of amyloid transthyretin cardiac amyloidosis (ATTR‐CA) and novel disease‐modifying therapies have prompted an active search for CA. We examined the ...prevalence of CA in different settings based on literature data.
Methods and results
We performed a systematic search for screening studies on CA, focusing on the prevalence, sex and age distribution in different clinical settings. The prevalence of CA in different settings was as follows: bone scintigraphy for non‐cardiac reasons (n = 5 studies), 1% (95% confidence interval CI 0%–1%); heart failure with preserved ejection fraction (n = 6), 12% (95% CI 6%–20%); heart failure with reduced or mildly reduced ejection fraction (n = 2), 10% (95% CI 6%–15%); conduction disorders warranting pacemaker implantation (n = 1), 2% (95% CI 0%–4%); surgery for carpal tunnel syndrome (n = 3), 7% (95% CI 5%–10%); hypertrophic cardiomyopathy phenotype (n = 2), 7% (95% CI 5%–9%); severe aortic stenosis (n = 7), 8% (95% CI 5%–13%); autopsy series of ‘unselected’ elderly individuals (n = 4), 21% (95% CI 7%–39%). The average age of CA patients in the different settings ranged from 74 to 90 years, and the percentage of men from 50% to 100%. Many patients had ATTR‐CA, but the average percentage of patients with amyloid light‐chain (AL) CA was up to 18%.
Conclusions
Searching for CA in specific settings allows to identify a relatively high number of cases who may be eligible for treatment if the diagnosis is unequivocal. ATTR‐CA accounts for many cases of CA across the different settings, but AL‐CA is not infrequent. Median age at diagnosis falls in the eighth or ninth decades, and many patients diagnosed with CA are women.
Objectives The purpose of this study was to determine the prevalence and prognostic role of left ventricular reverse remodeling (LVRR) in idiopathic dilated cardiomyopathy (IDCM). Background Tailored ...medical therapy can lead to LVRR in IDCM. The prevalence and prognostic impact of LVRR remain unclear. Methods We consecutively enrolled 361 IDCM patients. LVRR was defined as a left ventricular ejection fraction increase of ≥10 U or a left ventricular ejection fraction of ≥50% and a decrease in indexed left ventricular end-diastolic diameter of ≥10% or indexed left ventricular end-diastolic diameter of ≥33 mm/m2 at 24 months (range 9 to 36 months). Follow-up echocardiographic data were available for 242 patients (67%), 34 (9%) died/underwent heart transplantation (HTx) before re-evaluation, and 85 (24%) did not have a complete re-evaluation. After re-evaluation, the surviving patients were followed for 110 ± 53 months; there were 55 deaths (23%) and 32 HTx (13%). Results LVRR was found in 89 of 242 patients (37%). Baseline predictors of LVRR were higher systolic blood pressure (p = 0.047) and the absence of left bundle branch block (p = 0.009). When added to a prognostic baseline model including male sex, heart failure duration, New York Heart Association functional classes III to IV, LVEF, significant mitral regurgitation, and beta-blockers, LVRR, New York Heart Association functional classes III to IV, and significant mitral regurgitation after 24 months emerged as independent predictors of death/HTx and heart failure death/HTx. The model including follow-up variables showed additional prognostic power with respect to baseline model (for death/HTx, area under the curve: 0.80 vs. 0.70, respectively, p = 0.004). Furthermore, only LVRR was significantly associated with sudden death/major ventricular arrhythmia in the long-term. Conclusions LVRR characterized approximately one-third of IDCM patients surviving 2 years while receiving optimal medical therapy and allowed a more accurate long-term prognostic stratification of the disease.
Mutations in LMNA, which encodes the nuclear proteins Lamin A/C, can cause cardiomyopathy and conduction disorders. Here, we employ induced pluripotent stem cells (iPSCs) generated from human cells ...carrying heterozygous K219T mutation on LMNA to develop a disease model. Cardiomyocytes differentiated from these iPSCs, and which thus carry K219T-LMNA, have altered action potential, reduced peak sodium current and diminished conduction velocity. Moreover, they have significantly downregulated Na
1.5 channel expression and increased binding of Lamin A/C to the promoter of SCN5A, the channel's gene. Coherently, binding of the Polycomb Repressive Complex 2 (PRC2) protein SUZ12 and deposition of the repressive histone mark H3K27me3 are increased at SCN5A. CRISPR/Cas9-mediated correction of the mutation re-establishes sodium current density and SCN5A expression. Thus, K219T-LMNA cooperates with PRC2 in downregulating SCN5A, leading to decreased sodium current density and slower conduction velocity. This mechanism may underlie the conduction abnormalities associated with LMNA-cardiomyopathy.
Abstract Objective Atrial fibrillation is often asymptomatic, but outcomes require further characterization. The study objective was to investigate the clinical presentation, management, and outcomes ...in asymptomatic and symptomatic patients with atrial fibrillation who were prospectively enrolled in the EurObservational Research Programme – Atrial Fibrillation (EORP-AF) Pilot General Registry. Methods A total of 3119 patients were enrolled, and 1237 (39.7%) were asymptomatic (European Heart Rhythm Association EHRA score I). Among symptomatic patients, 963 (51.2%) had mild symptoms (EHRA score II) and 919 (48.8%) had severe or disabling symptoms (EHRA III-IV). Permanent atrial fibrillation was 3-fold more common in asymptomatic patients than in symptomatic patients. Results On multivariate analysis, male gender (odds ratio OR, 1.630; 95% confidence interval CI, 1.384-1.921), older age (OR, 1.019; 95% CI, 1.012-1.026), previous myocardial infarction (OR, 1.681; 95% CI, 1.350-2.093), and limited physical activity (OR, 1.757; 95% CI, 1.495-2.064) were associated significantly with asymptomatic (EHRA I) atrial fibrillation. Fully asymptomatic atrial fibrillation (absence of current and previous symptoms) was present in 520 patients (16.7%) and was associated independently with male gender, age, and previous myocardial infarction. Appropriate guideline-based prescription of oral anticoagulants was lower in these patients, and aspirin was prescribed more frequently. Mortality at 1 year was more than 2-fold higher in asymptomatic patients compared with symptomatic patients (9.4% vs 4.2%, P < .0001) and was associated independently with older age and comorbidities, including chronic kidney disease and chronic heart failure. Conclusions Asymptomatic atrial fibrillation is common in daily cardiology practice and is associated with elderly age, more comorbidities, and high thromboembolic risks. A higher 1-year mortality was found in asymptomatic patients compared with symptomatic patients.
Prompt coronary catheterization and revascularization have markedly improved the outcomes of myocardial infarction, but have also resulted in a growing number of surviving patients with permanent ...structural damage of the heart, which frequently leads to heart failure. There is an unmet clinical need for treatments for this condition
, particularly given the inability of cardiomyocytes to replicate and thereby regenerate the lost contractile tissue
. Here we show that expression of human microRNA-199a in infarcted pig hearts can stimulate cardiac repair. One month after myocardial infarction and delivery of this microRNA through an adeno-associated viral vector, treated animals showed marked improvements in both global and regional contractility, increased muscle mass and reduced scar size. These functional and morphological findings correlated with cardiomyocyte de-differentiation and proliferation. However, subsequent persistent and uncontrolled expression of the microRNA resulted in sudden arrhythmic death of most of the treated pigs. Such events were concurrent with myocardial infiltration of proliferating cells displaying a poorly differentiated myoblastic phenotype. These results show that achieving cardiac repair through the stimulation of endogenous cardiomyocyte proliferation is attainable in large mammals, however dosage of this therapy needs to be tightly controlled.
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