Search results for "Cardiomegaly"

Cardiomyocyte proliferation prevents failure in pressure overload but not volume overload

2017

Induction of the cell cycle is emerging as an intervention to treat heart failure. Here, we tested the hypothesis that enhanced cardiomyocyte renewal in transgenic mice expressing cyclin D2 would be beneficial during hemodynamic overload. We induced pressure overload by transthoracic aortic constriction (TAC) or volume overload by aortocaval shunt in cyclin D2-expressing and WT mice. Although cyclin D2 expression dramatically improved survival following TAC, it did not confer a survival advantage to mice following aortocaval shunt. Cardiac function decreased following TAC in WT mice, but was preserved in cyclin D2-expressing mice. On the other hand, cardiac structure and function were compr…

[Cardiac arrhythmias in hypertensive subjects with and without left ventricular hypertrophy compared to the circadian profile of the blood pressure].

1990

To evaluate possible correlations between cardiac arrhythmias and circadian pattern of blood pressure (BP) and of heart rate (HR), we studied 2 groups of 20 males with stable arterial hypertension of mild to moderate entity, with (Group I) or without (Group II) left ventricular hypertrophy (LVH). In patients with LVH the mean age (56 vs 46 years), the duration of the hypertensive state (48.1 vs 15.7 months), the thickening of interventricular septum (IVS; 13.7 vs 9.6 mm) and of the posterior wall of the left ventricle (13.2 vs 9.2 mm) and the mass of LV (149.8 vs 99.7 g/m2) were significantly greater (p less than 0.01). On the contrary, the 2 groups did not show significant differences conc…

Different prevalence of some indices of cardiac and vascular impairment in normal weight and obese patients with essential arterial hypertension

1989

Certain physiopathological features that differentiate essential arterial hypertension in normal weight and obese patients are recalled. The results of a retrospective study carried out in 293 hypertensive patients admitted to the Clinic in recent years are reported with a view to evaluating the prevalence of certain parameters (ischaemic cardiopathy, left ventricular hypertrophy, renal, vasculo-cerebral and retinal impairment) in patients subdivided into two groups: normal weight and obese. The study showed in the first group a higher prevalence of signs of ischaemic cardiopathy; in the second a higher prevalence of left ventricular hypertrophy. This difference is accentuated in the subgro…

Relation of endocrine and cardiac findings in acromegalics

1992

Cardiac involvement in 32 acromegalics was related to endocrine parameters, clinical score and duration of the disease as well as compared to that of 50 controls free of cardiac disease. Stress ECG, 24h Holter monitoring and echocardiography revealed that supraventricular premature complexes did not occur more often in acromegalics than in controls, both prevalence and severity of ventricular arrhythmia, however, were higher in patients compared to controls: 15/32 (48%) acromegalics had complex ventricular arrhythmia as compared with 6/50 (12%) normal subjects (p less than 0.01). Repetitive ventricular arrhythmia was manifest in 10/32 (31%) patients but only in 4/50 (8%) controls (p less th…

Relation between late potentials and echocardiographically determined left ventricular mass in healthy subjects.

1991

A member of the TGF-β superfamily, GDF11: functions in the cardiac regeneration, perhaps an “elixir of youth?”

2015

Endothelial Leptin Receptor Deletion Promotes Cardiac Autophagy and Angiogenesis Following Pressure Overload by Suppressing Akt/mTOR Signaling.

2019

Background: Cardiac remodeling is modulated by overnutrition or starvation. The adipokine leptin mediates energy balance between adipose tissue and brain. Leptin and its receptors are expressed in the heart. Methods and Results: To examine the importance of endothelial leptin signaling in cardiac hypertrophy, transverse aortic constriction was used in mice with inducible endothelium-specific deletion of leptin receptors (End.LepR-KO) or littermate controls (End.LepR-WT). End.LepR-KO was associated with improved left ventricular function (fractional shortening, 28.4% versus 18.8%; P =0.0114), reduced left ventricular dilation (end-systolic inner left ventricular diameter, 3.59 versus 4.08 m…

miR-133a Enhances the Protective Capacity of Cardiac Progenitors Cells after Myocardial Infarction

2014

Summary miR-133a and miR-1 are known as muscle-specific microRNAs that are involved in cardiac development and pathophysiology. We have shown that both miR-1 and miR-133a are early and progressively upregulated during in vitro cardiac differentiation of adult cardiac progenitor cells (CPCs), but only miR-133a expression was enhanced under in vitro oxidative stress. miR-1 was demonstrated to favor differentiation of CPCs, whereas miR-133a overexpression protected CPCs against cell death, targeting, among others, the proapoptotic genes Bim and Bmf. miR-133a-CPCs clearly improved cardiac function in a rat myocardial infarction model by reducing fibrosis and hypertrophy and increasing vasculari…

Myocardial maladaptation to pressure overload in CB2 receptor-deficient mice

2019

Abstract Background Adaptation to aortic valve stenosis leads to myocardial hypertrophy, which has been associated with inflammation, fibrosis and activation of the endocannabinoid system. Since the endocannabinoid system and the CB2 receptor provide cardioprotection and modulate immune response in experimental ischemia, we investigated the role of CB2 in a mouse model of cardiac pressure overload. Methods Transverse aortic constriction was performed in CB2 receptor-deficient (Cnr2−/−) mice and their wild-type littermates (Cnr2+/+). After echocardiography and Millar left heart catheter hemodynamic evaluation hearts were processed for histological, cellular and molecular analyses. Results Th…

Right ventricular collagen type III and IV gene expression increases during early phases of endurance training in hypobaric hypoxic condition

1997

The objective of this study was to examine the effects of prolonged exposure to hypobaric hypoxic condition, physical training and their combination on collagen type I, III and IV gene expression in the ventricles and atria of rat heart. Male rats were assigned to four groups: normobaric sedentary (NS) and trained (NT), and hypobaric sedentary (HS) and trained (HT). Exposure to and treadmill running training in hypobaric condition were carried out in a hypobaric chamber (770–740 mbar, 2250–2550 m). Experimental periods were 10, 21 and 56 days; the groups of 91 days served as recovery groups from experimental settings of 56 days. Exposure to hypobaric condition as such and in combination wit…