Aim: To elucidate the cardioprotective effects of T-type calcium channel blocker mibefradil and compare with that of the angiotensin-converting enzyme inhibitor ramipril in a stroke-prone spontaneously hypertensive rats (SHR-SP) model of congestive heart failure (CHF) after myocardial infarction (MI).
Methods: SHR-SP rats were subjected to permanent ligation of the left anterior decending coronary artery. Treatment with mibefradil (10 mg.kg(-1).d(-1)), ramipril (10 mg.kg(-1).d(-1)), or placebo was initiated 4 weeks before surgery and continued up to 6 weeks after induction of MI. Sham-operated rats served as controls.
Results: In placebo-treated MI rats, six weeks after MI, left ventricular circumference, inner diameter, and left ventricular end-diastolic pressure (LVEDP) were increased, whereas mean arterial blood pressure (MAP) and maximum rate of rise of left ventricular pressure (dp/dt(max)) were decreased compared with sham-operated controls (P<0.01). In ramipril-treated MI rats, heart weight, heart weight to body weight ratio and interstitial collagen content were reduced (P<0.05, P<0.01), LVEDP was slightly decreased (P>0.05), and dp/dt(max) was improved (P<0.01) compared with placebo-treated MI rats. In contrast, in mibefradil-treated MI rats, heart weight, heart weight to body weight ratio were slightly but not significantly reduced, LVEDP was slightly elevated compared with placebo-treated MI rats, and was elevated (P<0.05) compared with ramipril-treated MI rats, although interstitial collagen content were reduced (P<0.01) compared with placebo-treated MI rats.
Conclusion: Chronic treatment with ramipril diminishes cardiac remodeling of heart failure after MI to a greater extent than mibefradil. Moreover, 6 weeks after MI, mibefradil treatment results in a slight rise in LVEDP compared with placebo-treated rats. Therefore, treatment with mibefradil might be deleterious rather than beneficial compared with ramipril or even placebo treatment in experimental MI.
Download full-text PDF |
Source |
---|
Oper Neurosurg (Hagerstown)
September 2024
Department of Neurology, Washington University in St Louis, St Louis, Missouri, USA.
Background And Objectives: Surgical planning is critical to achieve optimal outcome in deep brain stimulation (DBS). The relationship between clinical outcomes and DBS electrode position relative to subthalamic nucleus (STN) is well investigated, but the role of surgical trajectory remains unclear. We sought to determine whether preoperatively planned DBS lead trajectory relates to adequate motor outcome in STN-DBS for Parkinson's disease (PD).
View Article and Find Full Text PDFPhysiol Res
December 2024
Department of Physiology, Faculty of Medicine, Masaryk University, Brno, Czech Republic.
Myocardial remodelling involves structural and functional changes in the heart, potentially leading to heart failure. The deoxycorticosterone acetate (DOCA)/salt model is a widely used experimental approach to study hypertension-induced cardiac remodelling. It allows to investigate the mechanisms underlying myocardial fibrosis and hypertrophy, which are key contributors to impaired cardiac function.
View Article and Find Full Text PDFPhysiol Res
December 2024
Children's Heart Center, Second Faculty of Medicine, Charles University and Motol University Hospital, Praha, Czech Republic.
Although the heart atria have a lesser functional importance than the ventricles, atria play an important role in the pathophysiology of heart failure and supraventricular arrhythmias, particularly atrial fibrillation. In addition, knowledge of atrial morphology recently became more relevant as cardiac electrophysiology and interventional procedures in the atria gained an increasingly significant role in the clinical management of patients with heart disease. The atrial chambers are thin-walled, and several vessels enter at the level of the atria.
View Article and Find Full Text PDFJ Thorac Cardiovasc Surg
January 2025
Coronary Center, Department of Thoracic and Cardiovascular Surgery, Miller Family Heart, Vascular, & Thoracic Institute, Cleveland Clinic, Cleveland, Ohio. Electronic address:
Cardiol Rev
January 2025
From the Department of Internal Medicine, Division of Cardiology, Wayne State University, Detroit, MI.
Heart failure (HF) poses a significant medical challenge, affecting millions of adults in the United States. High-output heart failure (HOHF) is a distinct subtype characterized by elevated cardiac output exceeding 8 L/min or a cardiac index >4 L/min/m². Patients with HOHF often present similarly to those with heart failure with reduced ejection fraction and heart failure with preserved ejection fraction.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!