A non-invasive method for estimating regional myocardial contractility in vivo would be of great value in the design and evaluation of new surgical and medical strategies to treat and/or prevent infarction-induced heart failure. As a first step towards developing such a method, an explicit finite element (FE) model-based formal optimization of regional myocardial contractility in a sheep with left ventricular (LV) aneurysm was performed using tagged magnetic resonance (MR) images and cardiac catheterization pressures. From the tagged MR images, 3-dimensional (3D) myocardial strains, LV volumes and geometry for the animal-specific 3D FE model of the LV were calculated, while the LV pressures provided physiological loading conditions. Active material parameters (T(max_B) and T(max_R)) in the non-infarcted myocardium adjacent to the aneurysm (borderzone) and in myocardium remote from the aneurysm were estimated by minimizing the errors between FE model-predicted and measured systolic strains and LV volumes using the successive response surface method for optimization. The significant depression in optimized T(max_B) relative to T(max_R) was confirmed by direct ex vivo force measurements from skinned fiber preparations. The optimized values of T(max_B) and T(max_R) were not overly sensitive to the passive material parameters specified. The computation time of less than 5 hours associated with our proposed method for estimating regional myocardial contractility in vivo makes it a potentially very useful clinical tool.
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http://dx.doi.org/10.1115/1.3148464 | DOI Listing |
J Clin Med
January 2025
Department of Cardiovascular & Thoracic Anaesthesia and Critical Care, University Hospital of Martinique, F-97200 Fort-de-France, Martinique, France.
Acute cardiovascular disorders are incriminated in up to 33% of maternal deaths, and the presence of sickle cell anemia (SCA) aggravates the risk of peripartum complications. Herein, we present a 24-year-old Caribbean woman with known SCA who developed a vaso-occlusive crisis at 36 weeks of gestation that required emergency Cesarean section. In the early postpartum period, she experienced fever with rapid onset of acute respiratory distress in the context of COVID-19 infection that required tracheal intubation and mechanical ventilatory support with broad-spectrum antibiotics and blood exchange transfusion.
View Article and Find Full Text PDFJ Clin Med
December 2024
Lakeland Regional Health Medical Center, Lakeland, FL 33805, USA.
The benefit of beta-blockers (BBs) for myocardial infarction (MI) patients with a preserved left ventricular ejection fraction (LVEF) is uncertain. While beneficial for a reduced LVEF, their efficacy with a preserved LVEF, especially with modern revascularization, is unclear. A PRISMA-guided systematic review and meta-analysis utilized PubMed and EMBASE.
View Article and Find Full Text PDFNutrients
December 2024
Department of Preventive Medicine and Public Health, School of Medicine-Clínica Universidad de Navarra, University of Navarra, Irunlarrea 1, 31008 Pamplona, Spain.
Background/objectives: Noncommunicable diseases, particularly cardiovascular disease (CVD), represent a significant global public health challenge, with unhealthy diets as a major risk factor. This study investigates the association between adherence to the Planetary Health Diet proposed by the EAT-Lancet Commission and CVD risk.
Methods: Utilizing data from the Seguimiento Universidad de Navarra (SUN) cohort, which included 18,656 participants (mean age 38 years; 61% women), we assessed dietary intake using a validated food frequency questionnaire and the Planetary Health Diet Index to evaluate adherence (range 0-42).
Int J Mol Sci
January 2025
School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510275, China.
Objective: The objective of this study was to explore the possibility of treating heart failure in rats by delivering mRNA of 24-dehydrocholesterol reductase (DHCR24) into the body through lipid nanoparticles (LNPs).
Methods: We established a heart failure rat model using doxorubicin. The experiment was divided into blank, model, mRNA stock solution cardiac injection, mRNA stock solution intravenous injection, LNP-mRNA stock solution cardiac injection, and LNP-mRNA stock solution intravenous injection groups.
Int J Mol Sci
December 2024
Department of Physiology and Pathophysiology, College of Medicine, Yanbian University, Yanji 133002, China.
Myocardial infarction (MI) is a highly challenging and fatal disease, with diverse challenges arising at different stages of its progression. As such, non-coding RNAs (ncRNAs), which can broadly regulate cell fate, and stem cells with multi-differentiation potential are emerging as novel therapeutic approaches for treating MI across its various stages. NcRNAs, including microRNAs (miRNAs) and long non-coding RNAs (LncRNAs), can directly participate in regulating intracellular signaling pathways, influence cardiac angiogenesis, and promote the repair of infarcted myocardium.
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