scholarly journals Resting Heart Rate and Chronotropic Response to Exercise: Prognostic Implications in Heart Failure Across the Left Ventricular Ejection Fraction Spectrum

2018 ◽  
Vol 24 (11) ◽  
pp. 753-762 ◽  
Author(s):  
Mário Santos ◽  
Erin West ◽  
Hicham Skali ◽  
Daniel E. Forman ◽  
Wilson Nadruz ◽  
...  
2000 ◽  
Vol 99 (1) ◽  
pp. 27-35 ◽  
Author(s):  
Stephan SCHMIDT-SCHWEDA ◽  
Christian HOLUBARSCH

In the failing human myocardium, both impaired calcium homoeostasis and alterations in the levels of contractile proteins have been observed, which may be responsible for reduced contractility as well as diastolic dysfunction. In addition, levels of a key protein in calcium cycling, i.e. the sarcoplasmic reticulum Ca2+-ATPase, and of the α-myosin heavy chain have been shown to be enhanced by treatment with etomoxir, a carnitine palmitoyltransferase inhibitor, in normal and pressure-overloaded rat myocardium. We therefore studied, for the first time, the influence of long-term oral application of etomoxir on cardiac function in patients with chronic heart failure. A dose of 80 mg of etomoxir was given once daily to 10 patients suffering from heart failure (NYHA functional class II–III; mean age 55±4 years; one patient with ischaemic heart disease and nine patients with dilated idiopathic cardiomyopathy; all male), in addition to standard therapy. The left ventricular ejection fraction was measured echocardiographically before and after a 3-month period of treatment. Central haemodynamics at rest and exercise (supine position bicycle) were defined by means of a pulmonary artery catheter and thermodilution. All 10 patients improved clinically; no patient had to stop taking the study medication because of side effects; and no patient died during the 3-month period. Maximum cardiac output during exercise increased from 9.72±1.25 l/min before to 13.44±1.50 l/min after treatment (P < 0.01); this increase was mainly due to an increased stroke volume [84±7 ml before and 109±9 ml after treatment (P < 0.01)]. Resting heart rate was slightly reduced (not statistically significant). During exercise, for any given heart rate, stroke volume was significantly enhanced (P < 0.05). The left ventricular ejection fraction increased significantly from 21.5±2.6% to 27.0±2.3% (P < 0.01). In acute studies, etomoxir showed neither a positive inotropic effect nor vasodilatory properties. Thus, although the results of this small pilot study are not placebo-controlled, all patients seem to have benefitted from etomoxir treatment. Etomoxir, which has no acute inotropic or vasodilatory properties and is thought to increase gene expression of the sarcoplasmic reticulum Ca2+-ATPase and the α-myosin heavy chain, improved clinical status, central haemodynamics at rest and during exercise, and left ventricular ejection fraction.


2021 ◽  
Author(s):  
Mohanad Alkhodari ◽  
Herbert F. Jelinek ◽  
Shiza Saleem ◽  
Leontios J. Hadjileontiadis ◽  
Ahsan H. Khandoker

Abstract Analysis of heart failure is important in clinical practice to ensure coronary artery disease (CAD) patients will be provided with appropriate timely treatment. The current gold standard, echocardiography, although reliable, provides a once-off left ventricular ejection fraction (LVEF) measurement but does not provide information about heart function the during day / night cardiac cycles. The aim of this study was to investigate the ability of heart rate variability (HRV) features in classifying CAD patients into multiple LVEF groups through a new index, HRV ejection fraction (HRVEF) and its agreement to established norms. A total of 92 heart failure patients were included in this study. HRVEF groups optimized on hourly basis through Jenks natural breaks algorithm exhibited a consistent pattern with a goodness of variance fit (GVF) of more than 0.70 accuracy during the late-night to early-morning (01:00-08:00) and evening (17:00-23:00) time periods. At these hours, several HRV features were found significant in differentiating between HRVEF groups using statistical analysis of variance (ANOVA) test. These features include the successive differences between normal heartbeats (RMSSD), low and high frequency (LF, HF) power, standard deviation of normal heartbeats (SD2), short-term scaling exponent (alpha1), and percentage of normal heartbeats in alternation segments (PAS). This study paves the way towards new LVEF guidelines based on the association between LVEF and HRV features for a better demonstration of the circadian cardiac function at different LVEF levels in CAD patients.


2020 ◽  
Vol 90 (1-2) ◽  
pp. 49-58 ◽  
Author(s):  
Wang Chunbin ◽  
Wang Han ◽  
Cai Lin

Abstract. Vitamin D deficiency commonly occurs in chronic heart failure. Whether additional vitamin D supplementation can be beneficial to adults with chronic heart failure remains unclear. We conducted a meta-analysis to derive a more precise estimation. PubMed, Embase, and Cochrane databases were searched on September 8, 2016. Seven randomized controlled trials that investigated the effects of vitamin D on cardiovascular outcomes in adults with chronic heart failure, and comprised 592 patients, were included in the analysis. Compared to placebo, vitamin D, at doses ranging from 2,000 IU/day to 50,000 IU/week, could not improve left ventricular ejection fraction (Weighted mean difference, WMD = 3.31, 95% confidence interval, CL = −0.93 to 7.55, P < 0.001, I2 = 92.1%); it also exerts no beneficial effects on the 6 minute walk distance (WMD = 18.84, 95% CL = −24.85 to 62.52, P = 0.276, I2 = 22.4%) and natriuretic peptide (Standardized mean difference, SMD = −0.39, 95% confidence interval CL = −0.48 to 0.69, P < 0.001, I2 = 92.4%). However, a dose-response analysis from two studies demonstrated an improved left ventricular ejection fraction with vitamin D at a dose of 4,000 IU/day (WMD = 6.58, 95% confidence interval CL = −4.04 to 9.13, P = 0.134, I2 = 55.4%). The results showed that high dose vitamin D treatment could potentially benefit adults with chronic heart failure, but more randomized controlled trials are required to confirm this result.


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