1,220 research outputs found
Heart Rate Variability in Idiopathic Dilated Cardiomyopathy: Characteristics and Prognostic Value
AbstractObjectives. This study was designed to evaluate heart rate variability (HRV) in patients with idiopathic dilated cardiomyopathy (IDC), to determine its correlation with hemodynamic variables and ventricular arrhythmias and to evaluate its prognostic value in IDC.Background. Previous studies have shown that HRV could predict arrhythmic events in patients after infarction, but the characteristics of HRV in IDC have not been fully established.Methods. Time domain analysis of HRV on 24-h electrocardiographic (ECG) recording was performed in 93 patients with IDC, and results were compared with those in 63 control subjects.Results. Patients with IDC, even those without congestive heart failure, had significantly lower values for HRV than those of control subjects. HRV was related to left ventricular shortening fraction (R = 0.5, p = 0.0001) and to peak oxygen uptake (R = 0.53, p = 0.01). HRV was not different in patients with runs of ventricular tachycardia or in patients with late potentials on the signal-averaged ECG. During a mean follow-up period (±SD) of 49.5 ± 35.6 months, patients with reduced HRV had an increased risk of cardiac death or heart transplantation (p = 0.006). On multivariate analysis, cardiac events were predicted by increased left ventricular end-diastolic diameter (p = 0.0001), reduced standard deviation of all normal to normal RR intervals (p = 0.02) and increased pulmonary capillary wedge pressure (p = 0.04).Conclusions. Decreased HRV in patients with IDC is related to left ventricular dysfunction and not to ventricular arrhythmias. Analysis of HRV can identify patients with IDC who have an increased risk of cardiac death or heart transplantation
Parallelization of a relaxation scheme modelling the bedload transport of sediments in shallow water flow
In this work we are interested in numerical simulations for bedload erosion
processes. We present a relaxation solver that we apply to moving dunes test
cases in one and two dimensions. In particular we retrieve the so-called
anti-dune process that is well described in the experiments. In order to be
able to run 2D test cases with reasonable CPU time, we also describe and apply
a parallelization procedure by using domain decomposition based on the
classical MPI library.Comment: 19 page
Programming implantable cardioverter-defibrillators in primary prevention: Higher or later
SummaryDefibrillator shocks, appropriate or not, are associated with significant morbidity, as they decrease quality of life, can be involved in depression and anxiety, and are known to be proarrhythmic. Most recent data have even shown an association between shocks and overall mortality. As opposed to other defibrillator-related complications, the rate of inappropriate and unnecessary shocks can (and should) be decreased with adequate programming. This review focuses on the different programming strategies and tips available to reduce the rate of shocks in primary prevention patients with left ventricular dysfunction implanted with a defibrillator, as well as some of the manufacturers’ device specificities
Stroke, thromboembolism and bleeding in patients with atrial fibrillation according to the EHRA valvular heart disease classification
International audienc
Heart failure with preserved ejection fraction and atrial fibrillation: recent advances and open questions.
Atrial fibrillation (AF) and heart failure (HF) are frequently associated and can be caused or exacerbated by each other through different mechanisms. AF is particularly common in patients with heart failure with preserved ejection fraction (HFpEF) defined as left ventricular ejection fraction (LVEF) ≥ 50%, with a prevalence ranging around 40-60%.In two recent trials, treatment with SGLT2 inhibitors resulted in a lower risk of worsening heart failure or cardiovascular death than placebo in patients with HFpEF, and SGLT2 inhibitors similarly improved prognosis whether patients had AF or not at enrolment. Analyses for subgroups of interest of patients with HFpEF likely to be at higher risk of AF (particularly those with older age or obesity) similarly indicated a consistent benefit with SGLT2 inhibitors. That subgroup in patients with HFpEF is those with a history of previous HF with LVEF ≤ 40%. The EAST-AFNET 4 trial indicated that early rhythm-control therapy was associated with a lower risk of adverse cardiovascular outcomes than usual care among patients with recent AF and cardiovascular conditions, including those with HF. In patients with AF and HF included in the CABANA trial, catheter ablation produced marked improvements in survival, freedom from AF recurrence, and quality of life compared to drug therapy. When strategies aiming at rhythm control eventually fail in patients with AF and HFpEF, a strategy of rate control with atrioventricular junction ablation and cardiac resynchronisation should be discussed since it may also reduce all-cause mortality.Finally, and in conclusion, considering that patients with AF and HFpEF may have a variety of cardiovascular and non-cardiovascular additional comorbidities, they are among those likely to have the highest clinical benefit being adherent to a holistic and integrated care management of AF following the ABC (Atrial Fibrillation Better Care) pathway
Yearly Incidence of Stroke and Bleeding in Atrial Fibrillation with Concomitant Hyperthyroidism: A National Discharge Database Study
Background: Hyperthyroidism is associated with atrial fibrillation (AF), and the latter is a major risk factor for stroke. Aim: We aimed to investigate the yearly incidence of stroke and bleeding in AF patients with and without concomitant hyperthyroidism from the French National Hospital Discharge Database. Methods: Admissions with AF between January 2010 and December 2019 were retrospectively identified and retrieved from the French national database. Incidence rates of ischaemic stroke and bleeding were compared in AF patients with and without concomitant hyperthyroidism. The associations of risk factors with ischaemic stroke were assessed by Cox regression. Results: Overall 2,421,087 AF patients, among whom 32,400 had concomitant hyperthyroidism were included in the study. During the follow-up (mean: 2.0 years, standard deviation SD: 2.2 years), the yearly incidence of ischaemic stroke was noted to be 2.6 (95% confidence interval CI: 2.5–2.8) in AF patients with concomitant hyperthyroidism, and 2.3 (95%CI: 2.3–2.4) in non-thyroid AF patients. Hyperthyroidism was noted as an independent risk factor for ischaemic stroke (adjusted hazard ratio aHR: 1.133, 95%CI: 1.080–1.189) overall, particularly within the first year of hyperthyroidism diagnosis (aHR 1.203, 95%CI 1.120–1.291), however, the association became non-significant in subsequent years (aHR 1.047, 95%CI 0.980–1.118). Major bleeding incidence was lower in the hyperthyroid AF group in comparison to the non-thyroid AF group (incidence ratio: 5.1 vs. 5.4%/year, p < 0.001). The predictive value of CHA(2)DS(2)VASc and HAS-BLED scores for ischaemic stroke and bleeding events, respectively, did not differ significantly between AF patients with or without concomitant hyperthyroidism. Conclusions: Hyperthyroidism seems to be an independent risk factor of ischaemic stroke in AF patients, particularly within the first year of hyperthyroidism diagnosis
The evolution of infrahissian conduction time in myotonic dystrophy patients: clinical implications
International audienc
Long-range dependencies in heart rate signals- revisited
The RR series extracted from human electrocardiogram signal (ECG) is
considered as a fractal stochastic process. The manifestation of long-range
dependencies is the presence of power laws in scale dependent process
characteristics. Exponents of these laws: - describing power spectrum
decay, - responsible for decay of detrended fluctuations or
related to, so-called, roughness of a signal, are known to differentiate hearts
of healthy people from hearts with congestive heart failure. There is a strong
expectation that resolution spectrum of exponents, so-called, local exponents
in place of global exponents allows to study differences between hearts in
details. The arguments are given that local exponents obtained in multifractal
analysis by the two methods: wavelet transform modulus maxima (WTMM) and
multifractal detrended fluctuation analysis (MDFA), allow to recognize the
following four stages of the heart: healthy and young, healthy and advance in
years, subjects with left ventricle systolic dysfunction (NYHA I--III class)
and characterized by severe congestive heart failure (NYHA III-IV class).Comment: 24 page
Retrospective Assessment of Childhood Sexual and Physical Abuse: A Comparison of Scaled and Behaviorally Specific Approaches
This study compared retrospective reports of childhood sexual and physical abuse as assessed by two measures: the Childhood Trauma Questionnaire (CTQ), which uses a Likert-type scaling approach, and the Computer Assisted Maltreatment Inventory (CAMI), which employs a behaviorally specific means of assessment. Participants included 1,195 undergraduate students recruited from three geographically diverse universities. Agreement was high across the two measures in the classification of victim status (92% and 80% for sexual and physical abuse, respectively). However, the CTQ classified more participants as sexually abused than did the CAMI, whereas the opposite trend was found for physical abuse. For child physical abuse, many participants reporting abusive acts on the CAMI scored below the cut-point for physical abuse on the CTQ. Classifi cation differences for both types of abuse were largely unrelated to demographic factors, socially desirable responding, or self-reported withholding of information. The implications of these results are discussed in light of future research using retrospective methods of assessing childhood abuse
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