Background: Treatment of heart failure patients with aldosterone antagonists has been shown to reduce the occurrence of sudden cardiac death. Therefore we aimed at determining the consequences of chronic exposure to aldosterone and the aldosterone antagonists eplerenone and spironolactone on the electrophysiological properties of the heart in a rat model.
Methods And Results: Male Wistar rats were chronically treated (4weeks) with aldosterone (ALD) via an osmotic minipump. Spironolactone (SPI) or eplerenone (EPL) was administered with the rat chow. ALD treated animals developed left ventricular hypertrophy, prolonged QT-intervals, a higher rate of ventricular premature beats and non-sustained ventricular tachycardia despite normal blood pressure values. Spironolactone and eplerenone were both able to inhibit the alterations. Left-ventricular mRNA expressions of Kv4.2 and Kv4.3 (Ito), Kv1.5 (IKur), Kir2.1 and Kir2.3 (IK1) and of Cav1.2 (L-type Ca(2+) channel) were significantly down-regulated in ALD. Correspondingly, the protein expressions of subunits Kv1.5, Kir2.3 and Cav1.2 were significantly decreased. A diminished calcineurin activity and mRNA expression of the Aß subunit of calcineurin were found in ALD, which was insensitive to aldosterone antagonists.
Conclusions: Chronic aldosterone-overload induces blood pressure independent structural and electrical remodeling of the myocardium resulting in an increased risk for malignant ventricular arrhythmias.
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http://dx.doi.org/10.1016/j.ijcard.2011.06.100 | DOI Listing |
Echocardiography
February 2025
Department of Cardiology, Loyola University Medical Center, Maywood, Illinois, USA.
The left atrium (LA) is pivotal in cardiac hemodynamics, serving as a dynamic indicator of left ventricular (LV) compliance and diastolic function. The LA undergoes structural and functional adaptations in response to hemodynamic stress, infiltrative processes, myocardial injury, and arrhythmic triggers. Remodeling of the LA in response to these stressors directly impacts pulmonary circulation, eventually leading to pulmonary capillary involvement, pulmonary artery hypertension, and eventually right ventricular failure.
View Article and Find Full Text PDFEchocardiography
February 2025
Department of Obstetrics and Gynecology, Ministry of Health, Ankara City Hospital, Ankara, Turkey.
Purpose: To investigate fetal cardiac functions and remodeling in pregnancies conceived via in vitro fertilization (IVF).
Methods: This prospective case-control study included 40 singleton IVF pregnancies and 46 uncomplicated control pregnancies at 28-36 weeks of gestation. The IVF group consisted of pregnancies applied to the outpatient clinic, excluding those with anatomical or chromosomal abnormalities.
Eur Heart J Cardiovasc Imaging
January 2025
Heart Institute. Department of Cardiology. Cardiovascular Imaging Unit. Hospital Universitari Germans Trias i Pujol, Barcelona, Spain.
Aims: How the underlying etiology and pathophysiology of left ventricular (LV) hypertrophy affects LA remodeling and function remains unexplored. The present study aims to investigate the influence of various hypertrophic phenotypes on LA remodeling and function.
Methods And Results: Patients with LV hypertrophy who underwent cardiac magnetic resonance (CMR) were compared to a control group.
Rev Cardiovasc Med
January 2025
Department of Cardiology, Renmin Hospital of Wuhan University, 430060 Wuhan, Hubei, China.
With a better understanding of the susceptibility to atrial fibrillation (AF) and the thrombogenicity of the left atrium, the concept of atrial cardiomyopathy (ACM) has emerged. The conventional viewpoint holds that AF-associated hemodynamic disturbances and thrombus formation in the left atrial appendage are the primary causes of cardiogenic embolism events. However, substantial evidence suggests that the relationship between cardiogenic embolism and AF is not so absolute, and that ACM may be an important, underestimated contributor to cardiogenic embolism events.
View Article and Find Full Text PDFJ Clin Med Res
January 2025
Department of Life, Health and Environmental Science, University of L'Aquila, L'Aquila, Italy.
Left ventricular non-compaction (LVNC) is a rare primary cardiomyopathy with genetic etiology, resulting from an abnormality of myocardial development during embryogenesis. It carries an elevated risk of left ventricular dysfunction, thromboembolic events and malignant arrhythmias. We report the case of LVNC associated with paroxysmal atrial fibrillation and ankyrin 2 () mutation at the genetic test.
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