Impaired subendocardial function in tachycardia-induced cardiac failure

1995 ◽  
Vol 268 (5) ◽  
pp. H1788-H1794 ◽  
Author(s):  
I. J. LeGrice ◽  
Y. Takayama ◽  
J. W. Holmes ◽  
J. W. Covell
Keyword(s):  
Heart Failure ◽  
Diastolic Pressure ◽  
Substantial Reduction ◽  
Median Sternotomy ◽  
Vena Cava ◽  
Oxygen Demand ◽  
Experimental Models ◽  
Left Ventricular ◽  
Miniature Swine ◽  
Reduced Ejection Fraction

Chronic rapid ventricular pacing (CRVP) in many experimental models induces ventricular dilatation, reduced ejection fraction, and symptomatic congestive heart failure. We have investigated transmural mechanical function in the left ventricular (LV) wall of five Hanford miniature swine before and after CRVP-induced failure. Three columns of radiopaque markers 1 mm in diameter were implanted in the anterior LV wall through a median sternotomy. A pair of LV pacing wires were sutured into the myocardium, a pneumatic cuff was placed around the inferior vena cava (IVC), and two fluid-filled Silastic catheters were implanted into the LV apex. Two weeks after surgery, the pigs were suspended awake in a sling, and markers were tracked with biplane cineradiography. The hearts were paced for 3 wk (225-240 beats/min), and the study was repeated with the pacemaker off. Saline infusion and IVC occlusion were used to vary LV end-diastolic pressure (EDP) so control-to-failure comparisons could be made at matched LV EDPs. End-systolic strains in the circumferential (E11), longitudinal (E22), and transmural (E33) directions were quantified using finite element methods. There was a significant reduction in E11 and E33 for the subendocardium: in E11, from -0.27 to -0.18; in E33, from 0.83 to 0.46. There were no significant changes in subendocardial E22 or in any of the outer wall normal strains. These results indicate that CRVP causes substantial reduction of subendocardial, but not subepicardial, function; taken together with previous data indicating subendocardial hypoperfusion, these results support the contention that an imbalance between blood flow and oxygen demand plays a role in the etiology of heart failure in this model.

DNA enzyme targeting TNF-α mRNA improves hemodynamic performance in rats with postinfarction heart failure

2001 ◽  
Vol 281 (5) ◽  
pp. H2211-H2217 ◽  
Author(s):  
Per Ole Iversen ◽  
Gunnar Nicolaysen ◽  
Mouldy Sioud
Keyword(s):  
Heart Failure ◽  
Therapeutic Potential ◽  
Diastolic Pressure ◽  
Substantial Reduction ◽  
Left Ventricular ◽  
Lung Weight ◽  
Cleavage Activity ◽  
Arterial Blood ◽  
Modified Dna ◽  
Tnf Α

Tumor necrosis factor-α (TNF-α) probably affects the pathogenesis of heart failure. Here we have investigated the therapeutic potential of a nuclease-resistant DNA enzyme that specifically cleaves TNF-α mRNA. A phosphorothioate-modified DNA enzyme was designed to retain similar cleavage activity as its unmodified version, and that inhibited the expression of TNF-α in vitro. To test its efficacy in vivo, postinfarction congestive heart failure was induced in anesthetized rats by ligation of the left coronary artery. A 4-wk treatment with the DNA enzyme induced a substantial reduction in left ventricular end-diastolic pressure and lung weight concomitant with an increase in arterial blood pressure and myocardial blood flow compared with controls. The concentration of TNF-α in coronary sinus blood was markedly lowered on treatment, and myocardial TNF-α mRNA was substantially reduced. Recovery studies showed that the DNA enzyme cleavage activity was present within the myocardium throughout the observation period and had no apparent toxic effects. Our findings indicate that DNA enzyme-based therapy may hold promise in the treatment of this debilitating disease.

Congestive Heart Failure in Copper-Deficient Mice

2003 ◽  
Vol 228 (7) ◽  
pp. 811-817 ◽  
Author(s):  
Laila Elsherif ◽  
Raymond V. Ortines ◽  
Jack T. Saari ◽  
Y. James Kang
Keyword(s):  
Heart Failure ◽  
Congestive Heart Failure ◽  
Left Ventricle ◽  
Diastolic Pressure ◽  
Systolic Pressure ◽  
Pressure Rise ◽  
Experimental Models ◽  
Left Ventricular ◽  
Mouse Heart ◽  
Total Period

Copper Deficiency (CuD) leads to hypertrophic cardiomyopathy in various experimental models. The morphological, electrophysiological, and molecular aspects of this hypertrophy have been under investigation for a long time. However the transition from compensated hypertrophy to decompensated heart failure has not been investigated in the study of CuD. We set out to investigate the contractile and hemodynamic parameters of the CuD mouse heart and to determine whether heart failure follows hypertrophy in the CuD heart. Dams of FVB mice were fed CuD or copper-adequate (CuA) diet starting from the third day post delivery and the weanling pups were fed the same diet for a total period of 5 weeks (pre- and postweanling). At week 4, the functional parameters of the heart were analyzed using a surgical technique for catheterizing the left ventricle. A significant decrease in left ventricle systolic pressure was observed with no significant change in heart rate, and more importantly contractility as measured by the maximal rate of left ventricular pressure rise (+dP/dt) and decline (−dP/dt) were significantly depressed in the CuD mice. However, left ventricle end diastolic pressure was elevated, and relaxation was impaired in the CuD animals; the duration of relaxation was prolonged. In addition to significant changes in the basal level of cardiac function, CuD hearts had a blunted response to the stimulation of the β-adrenergic agonist isoproterenol. Furthermore, morphological analysis revealed increased collagen accumulation in the CuD hearts along with lipid deposition. This study shows that CuD leads to systolic and diastolic dysfunction in association with histopathological changes, which are indices commonly used to diagnose congestive heart failure.

Afterload-induced diastolic dysfunction contributes to high filling pressures in experimental heart failure with preserved ejection fraction

2015 ◽  
Vol 309 (10) ◽  
pp. H1648-H1654 ◽  
Author(s):  
Sara Leite ◽  
Sara Rodrigues ◽  
Marta Tavares-Silva ◽  
José Oliveira-Pinto ◽  
Mohamed Alaa ◽  
...  
Keyword(s):  
Heart Failure ◽  
Ejection Fraction ◽  
Diastolic Pressure ◽  
Vena Cava ◽  
Left Ventricular ◽  
Preserved Ejection Fraction ◽  
Stiffness Constant ◽  
Complete Relaxation ◽  
Filling Time ◽  
Wistar Kyoto

Myocardial stiffness and upward-shifted end-diastolic pressure-volume (P-V) relationship (EDPVR) are the key to high filling pressures in heart failure with preserved ejection fraction (HFpEF). Nevertheless, many patients may remain asymptomatic unless hemodynamic stress is imposed on the myocardium. Whether delayed relaxation induced by pressure challenge may contribute to high end-diastolic pressure (EDP) remains unsettled. Our aim was to assess the effect of suddenly imposed isovolumic afterload on relaxation and EDP, exploiting a highly controlled P-V experimental evaluation setup in the ZSF1 obese rat (ZSF1 Ob) model of HFpEF. Twenty-week-old ZSF1 Ob ( n = 12), healthy Wistar-Kyoto rats (WKY, n = 11), and hypertensive ZSF1 lean control rats (ZSF1 Ln, n = 10) underwent open-thorax left ventricular (LV) P-V hemodynamic evaluation under anesthesia with sevoflurane. EDPVR was obtained by inferior vena cava occlusions to assess LV ED chamber stiffness constant β, and single-beat isovolumic afterload acquisitions were obtained by swift occlusions of the ascending aorta. ZSF1 Ob showed increased ED stiffness, delayed relaxation, as assessed by time constant of isovolumic relaxation (τ), and elevated EDP with normal ejection fraction. Isovolumic afterload increased EDP without concomitant changes in ED volume or heart rate. In isovolumic beats, relaxation was delayed to the extent that time for complete relaxation as predicted by 3.5 × monoexponentially derived τ (τexp) exceeded effective filling time. EDP elevation correlated with reduced time available to relax, which was the only independent predictor of EDP rise in multiple linear regression. Our results suggest that delayed relaxation during pressure challenge is an important contributor to lung congestion and effort intolerance in HFpEF.

scholarly journals Effects of Apelin on Left Ventricular-Arterial Coupling and Mechanical Efficiency in Rats with Ischemic Heart Failure

2019 ◽  
Vol 2019 ◽  
pp. 1-9 ◽  
Author(s):  
Qiufang Ouyang ◽  
Tao You ◽  
Jinjian Guo ◽  
Rong Xu ◽  
Quehui Guo ◽  
...  
Keyword(s):  
Heart Failure ◽  
Cardiac Fibrosis ◽  
Diastolic Pressure ◽  
Systolic Function ◽  
Mechanical Efficiency ◽  
Left Ventricular ◽  
Mesenteric Arteries ◽  
Stroke Work ◽  
Reduced Ejection Fraction ◽  
Left Ventricular Arterial Coupling

Apelin plays important roles in cardiovascular homeostasis. However, its effects on the mechanoenergetics of heart failure (HF) are unavailable. We attempted to investigate the effects of apelin on the left ventricular-arterial coupling (VAC) and mechanical efficiency in rats with HF. HF was induced in rats by the ligation of the left coronary artery. The ischemic HF rats were treated with apelin or saline for 12 weeks. The sham-operated animals served as the control. The left ventricular (LV) afterload and the systolic and diastolic functions, as well as the mechanoenergetic indices were estimated from the pressure-volume loops. Myocardial fibrosis by Masson’s trichrome staining, myocardial apoptosis by TUNEL, and collagen content in the aorta as well as media area in the aorta and the mesenteric arteries were determined. Our data indicated that HF rats manifested an increased arterial load (Ea), a declined systolic function (reduced ejection fraction, +dP/dtmax, end-systolic elastance, and stroke work), an abnormal diastolic function (elevated end-diastolic pressure, τ, and declined −dP/dtmax), and decreased mechanical efficiency. Apelin treatment improved those indices. Concomitantly, increased fibrosis in the LV myocardium and the aorta and enhanced apoptosis in the LV were partially restored by apelin treatment. A declined wall-to-lumen ratio in the mesenteric arteries of the untreated HF rats was further reduced in the apelin-treated group. We concluded that the rats with ischemic HF were characterized by deteriorated LV mechanoenergetics. Apelin improved mechanical efficiency, at least in part, due to the inhibiting cardiac fibrosis and apoptosis in the LV myocardium, reducing collagen deposition in the aorta and dilating the resistant artery.

scholarly journals Heart Failure with Preserved Ejection Fraction – Concept, Pathophysiology, Diagnosis and Challenges for Treatment

2015 ◽  
Vol 3 (3) ◽  
pp. 521-527 ◽  
Author(s):  
Lidija Veterovska Miljkovik ◽  
Vera Spiroska
Keyword(s):  
Heart Failure ◽  
Atrial Fibrillation ◽  
Ejection Fraction ◽  
Diastolic Dysfunction ◽  
Diastolic Pressure ◽  
Coronary Revascularization ◽  
Left Ventricular ◽  
Heart Catheterization ◽  
Elevated Concentration ◽  
Reduced Ejection Fraction

Heart failure (HF) with preserved left ventricular (LV) ejection fraction (HFpEF) occurs in 40 to 60% of the patients with HF, with a prognosis which is similar to HF with reduced ejection fraction (HFrEF). HFpEF pathophysiology is different from that of HFrEF, and has been characterized with diastolic dysfunction. Diastolic dysfunction has been defined with elevated left ventricular stiffness, prolonged iso-volumetric LV relaxation, slow LV filing and elevated LV end-diastolic pressure. Arterial hypertension occurs in majority cases with HFpEF worldwide. Patients are mostly older and obese. Diabetes mellitus and atrial fibrillation appear proportionally in a high frequency of patients with HFpEF. The HFpEF diagnosis is based on existence of symptoms and signs of heart failure, normal or approximately normal ejection and diagnosing of LV diastolic dysfunction by means of heart catheterization or Doppler echocardiography and/or elevated concentration of plasma natriuretic peptide. The present recommendations for HFpEF treatment include blood pressure control, heart chamber frequency control when atrial fibrillation exists, in some situations even coronary revascularization and an attempt for sinus rhythm reestablishment. Up to now, it is considered that no medication or a group of medications improve the survival of HFpEF patients. Due to these causes and the bad prognosis of the disorder, rigorous control is recommended of the previously mentioned precipitating factors for this disorder. This paper presents a universal review of the most important parameters which determine this disorder.

Abstract 3361: Progressive Left Ventricle, Myocyte Dysfunction, and Heart Failure in the Lethality of Anthrax Toxin in Conscious Dogs

Circulation ◽  
2007 ◽  
Vol 116 (suppl_16) ◽  
Author(s):  
Che-Ping Cheng ◽  
Satoshi Masutani ◽  
Heng-Jie Cheng ◽  
Michael Cross ◽  
Chun-Xian Zhang ◽  
...  
Keyword(s):  
Heart Failure ◽  
Diastolic Pressure ◽  
Contractile Function ◽  
Left Ventricular ◽  
Conscious Dogs ◽  
Pathologic Finding ◽  
Primary Role ◽  
Similar Time ◽  
Reduced Ejection Fraction ◽  
Cardiac Depression

Background . Bacillus anthracis ( BA ) infection is a cause of human and animal disease and associated with biowarfare. Although circulatory shock related to anthrax lethal toxin (LeTx) may play a primary role in lethality due to BA infection, its mechanisms are unclear. Methods . Six chronically-instrumented conscious dogs were assigned to receive a bolus injection of LeTx (10 ml saline with equivalent doses PA/LF, about 0.265 mg/kg, iv, n = 2) or saline (10 ml, iv, n = 4). Hemodynamic, left ventricular (LV) systolic and diastolic responses were determined periodically until 96 hours (h) in both groups. LV biopsies were performed at about 98H (before death). Isolated myocyte contractile function and histopathological alterations were determined. Results . Compared with control, in LeTx-treated animals, there were progressive decreases in LV contractility and slowed LV relaxation during the transition from LV dysfunction to heart failure (HF) over 96–98H. The cardiac depression was apparent about 6 – 8H after LeTx, but progressed through the subsequent 72–98H. At 72H after LeTx, heart rate (LeTx:129vsControl:95 bpm), LV end-diastolic pressure (P) (21vs9 mmHg), and the time constant of relaxation (40.9vs29.7 ms) were increased with markedly reduced ejection fraction, stroke volume (SV, 8.4vs15.8 ml), and end-systolic P (92vs118 mmHg). Moreover, LV contractility was decreased 49% (E ES , 4.1vs8.2 mmHg/ml and M SW , 44.9vs88.9 mmHg) with rightward shifts of LV P-V loops. At 96H, M SW , SV, and EF were further decreased accompanied by the development of severe HF. Pathologic finding of LV dilatation was associated with significantly increased length of LV myocytes (201±11vs122±13 μm). In LeTx-treated myocytes, there were about 46% reductions in cell contraction (79.0±9.7vs146.2±11.4 μm/s) and relaxation, respectively. LeTx produced lethality in dogs 4 days after LeTx treatment with similar time courses to those previously reported in man. Conclusions . LeTx causes direct and time-dependent progressive decrease in LV contractility, slow relaxation, cardiomyocyte dysfunction, LV, and myocyte remodeling and leads to HF, which suggests that the heart could be the primary target for the action of LeTx and plays an important role in lethality due to BA infection.

scholarly journals Left Atrial Volume Index in Diagnosis of Heart Failure With Preserved Ejection Fraction

2021 ◽  
Author(s):  
Xingxue Pang ◽  
Ruoyi Liu ◽  
Li Xu ◽  
Xin Tao ◽  
Xuezeng Hao ◽  
...  
Keyword(s):  
Heart Failure ◽  
Ejection Fraction ◽  
Diastolic Pressure ◽  
Left Atrial Volume ◽  
Left Ventricular ◽  
Volume Index ◽  
Control Group ◽  
Preserved Ejection Fraction ◽  
Left Atrial Volume Index ◽  
Reduced Ejection Fraction

Abstract Objective To assess the value of left atrium volume index（LAVI）for diagnosing heart failure with preserved ejection fraction (HFpEF) based on the invasive determination of left ventricular end-diastolic pressure (LVEDP).Methods A total of 710 cases of patients with dyspnea (LVEF≥50%) were enrolled in this retrospective study. Left ventricular end-diastolic pressure (LVEDP) was measured through selective coronary angiography. According to the value of LVEDP, cases were divided into the HFpEF group ( LVEDP≥15mmHg) and the control group (LVEDP<15mmHg). LAVI was calculated based on cardiac compartment diameter, as measured by echocardiography, and body surface area (BSA). Differences of LAVI between the HFpEF group and the control group, and between subgroups in the HFpEF group were analyzed.Results The difference in LAVI between the control group and the HFpEF group was statistically significant (41.35±2.28vs.46.78±2.63ml/m2, p=0.008). LVEDP was positively correlated with LAVI (Pearson: r=0.787, P＜0.001). When LAVI took the best cutoff value of 43.7 mm/m2, the sensitivity and specificity of diagnosis of HFpEF were 92.0% and 88.9%. When the boundary value of LAVI was from 41.7 to 45.7 mm/m2, the sensitivity of the diagnosis of ejection fraction retention heart failure was from 97.4% to 64.4% and the specificity was from 51.2.0% to 92.2%.Conclusion In patients with dyspnea after exclusion of heart failure with reduced ejection fraction (HFrEF), LAVI is positively correlated with LVEDP. LAVI can be used to diagnose HFpEF when HFrEF is excluded.

Heart Failure with Preserved Ejection Fraction – A Review

2012 ◽  
Vol 9 (1) ◽  
pp. 90-95 ◽  
Author(s):  
Otto A Smiseth ◽  
Anders Opdahl ◽  
Espen Boe ◽  
Helge Skulstad
Keyword(s):  
Heart Failure ◽  
Ejection Fraction ◽  
Diastolic Heart Failure ◽  
The Elderly ◽  
Left Ventricular ◽  
Filling Pressure ◽  
Left Ventricular Ejection ◽  
Ventricular Ejection Fraction ◽  
Reduced Ejection Fraction ◽  
Objective Evidence

Heart failure with preserved left ventricular ejection fraction (HF-PEF), sometimes named diastolic heart failure, is a common condition most frequently seen in the elderly and is associated with arterial hypertension and left ventricular (LV) hypertrophy. Symptoms are attributed to a stiff left ventricle with compensatory elevation of filling pressure and reduced ability to increase stroke volume by the Frank-Starling mechanism. LV interaction with stiff arteries aggravates these problems. Prognosis is almost as severe as for heart failure with reduced ejection fraction (HF-REF), in part reflecting co-morbidities. Before the diagnosis of HF-PEF is made, non-cardiac etiologies must be excluded. Due to the non-specific nature of heart failure symptoms, it is essential to search for objective evidence of diastolic dysfunction which, in the absence of invasive data, is done by echocardiography and demonstration of signs of elevated LV filling pressure, impaired LV relaxation, or increased LV diastolic stiffness. Antihypertensive treatment can effectively prevent HF-PEF. Treatment of HF-PEF is symptomatic, with similar drugs as in HF-REF.

Prognostic value of global longitudinal layer specific strain for patients with heart failure with reduced ejection fraction

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
C Johnsen ◽  
M Sengeloev ◽  
P Joergensen ◽  
N Bruun ◽  
D Modin ◽  
...  
Keyword(s):  
Heart Failure ◽  
Ejection Fraction ◽  
Prognostic Value ◽  
Left Ventricular ◽  
Volume Index ◽  
Funding Source ◽  
Reduced Ejection Fraction ◽  
Patients With Heart Failure ◽  
All Cause Mortality ◽  
Echocardiographic Parameters

Abstract Background Novel echocardiographic software allows for layer-specific evaluation of myocardial deformation by 2-dimensional speckle tracking echocardiography. Endocardial, epicardial- and whole wall global longitudinal strain (GLS) may be superior to conventional echocardiographic parameters in predicting all-cause mortality in patients with heart failure with reduced ejection fraction (HFrEF). Purpose The purpose of this study was to investigate the prognostic value of endocardial-, epicardial- and whole wall GLS in patients with HFrEF in relation to all-cause mortality. Methods We included and analyzed transthoracic echocardiographic examinations from 1,015 patients with HFrEF. The echocardiographic images were analyzed, and conventional and novel echocardiographic parameters were obtained. A p value in a 2-sided test &lt;0.05 was considered statistically significant. Cox proportional hazards regression models were constructed, and both univariable and multivariable hazard ratios (HRs) were calculated. Results During a median follow-up time of 40 months, 171 patients (16.8%) died. A lower endocardial (HR 1.17; 95% CI (1.11–1.23), per 1% decrease, p&lt;0.001), epicardial (HR 1.20; 95% CI (1.13–1.27), per 1% decrease, p&lt;0.001), and whole wall (HR 1.20; 95% CI (1.14–1.27), per 1% decrease, p&lt;0.001) GLS were all associated with higher risk of death (Figure 1). Both endocardial (HR 1.12; 95% CI (1.01–1.23), p=0.027), epicardial (HR 1.13; 95% CI (1.01–1.26), p=0.040) and whole wall (HR 1.13; 95% CI (1.01–1.27), p=0.030) GLS remained independent predictors of mortality in the multivariable models after adjusting for significant clinical parameters (age, sex, total cholesterol, mean arterial pressure, heart rate, ischemic cardiomyopathy, percutaneous transluminal coronary angioplasty and diabetes) and conventional echocardiographic parameters (left ventricular (LV) ejection fraction, LV mass index, left atrial volume index, deceleration time, E/e', E-velocity, E/A ratio and tricuspid annular plane systolic excursion). No other echocardiographic parameters remained an independent predictors after adjusting. Furthermore, endocardial, epicardial and whole wall GLS had the highest C-statistics of all the echocardiographic parameters. Conclusion Endocardial, epicardial and whole wall GLS are independent predictors of all-cause mortality in patients with HFrEF. Furthermore, endocardial, epicardial and whole wall GLS were superior prognosticators of all-cause mortality compared with all other echocardiographic parameters. Funding Acknowledgement Type of funding source: Public hospital(s). Main funding source(s): Herlev and Gentofte Hospital

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