This study aimed at investigating the role of ventricular volume (VV), left ventricular pressure (LVP) and myocardial contractility in causing changes in coronary flow (CF), in the absence of autoregulation. Changes in VV and, consequently, in LVP and myocardial contractility were induced in 5 anesthetized dogs using an extracorporeal circulation including a heart-lung machine. Left VV was changed in steps of 10 ml, from a lowest value of 10 ml to a maximum value of 70 ml and back, by introducing and subtracting different volumes of water in and from a latex balloon placed in the left ventricle. In order to suppress any interference by autoregulatory mechanisms, the experimental manoeuvres were performed in the presence of complete coronary vasodilation obtained with dipyridamole. Each increase in VV was accompanied by an increase in diastolic LVP which was in turn responsible for a greater development of pressure by the myocardial contraction, thus producing an increase in systolic LVP. Then, the pressure developed by the myocardial contraction, considered as the difference between systolic and diastolic LVP, decreased when the ventricle was dilated to 60 and 70 ml. Diastolic CF decreased only starting from a ventricular volume of 60 ml, varying independently of the changes in diastolic LVP. In addition, the amplitude of the coronary flow reduction in systole was found to change together with the pressure developed by the myocardial contraction with which showed a significant linear correlation. During the reduction in VV, a progressive fall of diastolic LVP occurred without any significant difference with respect to the phase of increased volumes; on the contrary, systolic LVP, at each ventricular volume, was lower than in the previous phase. Also diastolic CF, when the volume was progressively reduced, was lower than in the previous manoeuvre. The amplitude of the systolic flow reduction and the pressure produced by the contraction both decreased when the ventricular volume was reduced showing a significant linear correlation. The reduction of the pressure produced by the contraction is likely to be due to a loss of contractility after the ventricle was expanded more than 3 times its resting volume. It is concluded that changes in ventricular pressure do not influence phasic CF directly and that diastolic CF decreases only following extreme ventricular dilation. Finally, systolic flow reduction is seen to depend on the myocardial contractility and not on the levels reached by the pressure inside the ventricle.
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Mol Genet Metab
January 2025
Image Processing & Analysis Core (iPAC), Department of Radiology, University of Massachusetts Chan Medical School, Worcester, MA, USA. Electronic address:
Objective: GM1 gangliosidosis is a rare lysosomal storage disorder characterized by the accumulation of GM1 gangliosides in neuronal cells, resulting in severe neurodegeneration. Currently, limited data exists on the brain volumetric changes associated with this disease. This study focuses on the late-infantile and juvenile subtypes of type II GM1 gangliosidosis, aiming to quantify brain volumetric characteristics to track disease progression.
View Article and Find Full Text PDFSci Rep
January 2025
Instituto do Coração (InCor), Faculdade de Medicina, Hospital das Clínicas HCFMUSP, Universidade de São Paulo, São Paulo, Brazil.
Doxorubicin-induced cardiomyopathy (DOX-IC) is a significant and common complication in patients undergoing chemotherapy, leading to cardiac remodeling and reduced heart function. We hypothesized that the intrapericardial injection of hydrogels derived from the cardiac decellularized extracellular matrix (dECM) loaded with adipose tissue-derived stromal cells (ASC) and their secretome dampens or reverses the progression of DOX-IC. DOX-IC was induced in Wistar male rats through ten weekly intra-peritoneal injections of doxorubicin (cumulative dose: 18 mg/kg).
View Article and Find Full Text PDFEur 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.
Future Cardiol
January 2025
Echocardiography research Center, Rajaie cardiovascular medical and research Center, Iran University of Medical Science, Tehran, Iran.
Introduction: Decreased left atrial appendage emptying velocity (LAAV) is a marker for thrombus formation. This study evaluates the association between LAAV and inflammatory indices in non-valvular atrial fibrillation (AF) patients.
Methods: The study population was 1428 patients with AF, 875 of whom enrolled.
Surg Radiol Anat
January 2025
Department of Neurosurgery, Saitama Sekishinkai Hospital, 2-37-20 Irumagawa, Sayama, Saitama, 350-1305, Japan.
Purpose: To describe a case of short common trunk of the occipital artery (OA) and ascending pharyngeal artery (APA) arising from the internal carotid artery (ICA).
Methods: A 36-year-old woman with a history of surgical resection of a right lateral ventricular meningioma and atheromatous plaque of the right ICA underwent cranial magnetic resonance (MR) imaging and MR angiography of the head and neck region with a 3-Tesla scanner.
Results: MR angiography of the neck region showed a small atheromatous plaque at the origin of the right ICA and an anomalous artery arising from the posteromedial aspect of the right ICA at the distal end of the carotid bulb.
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