Twenty years' experience with continuous endocardial stimulation of the heart is summed up. The bulk of the reviewed data falls to the period of 1980 through 1985, when 1776 primary implantations were performed, whereas more than 3,000 implantations have been performed in the past 6 years. Opinions are voiced on many aspects related to endocardial stimulation. Endocardial application of electrodes is believed to be the principal method, while myocardial stimulation should only be done simultaneously with heart surgery. Electrode application via puncture is discussed with special reference to its advantages (possible application of two electrodes at once, small cosmetic defect) and possible side effects. The results obtained with a borer electrode, designed by the authors, are reported (130 cases). Complications associated with developing rhythm competition are discussed. It is proposed that the manufacture of asynchronous pacemakers be limited considerably, and that they should mostly be implanted in cases of clinically manifest myopotential inhibition.
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J Am Heart Assoc
December 2024
Centro Nacional de Investigaciones Cardiovasculares (CNIC) Novel Arrhythmogenic Mechanisms Program Madrid Spain.
Background: Electrophysiological characterization of ventricular tachycardia (VT) isthmus sites is complex and time-consuming. We aimed at developing and validating a global mapping strategy during programmed ventricular stimulation (PVS) to reveal the underlying electrophysiological properties of the infarct-related substrate and to enable identification of highly heterogeneous activation sites associated with protected VT isthmus sites.
Methods And Results: Experimental study that included 22 pigs with established myocardial infarction undergoing in vivo characterization of the anatomical and functional myocardial substrate associated with potential arrhythmogenicity.
Cardiology
November 2024
People's Liberation Army General Hospital of Southern Theatre Command, Guangzhou, China.
Introduction: The aim of the study was to investigate the differences in safety and efficacy between high-frequency stimulation (HFS) and anatomically guided endocardial catheter ablation (AA) of the ganglionated plexi (GPs) for treating vasovagal syncope (VVS) in individuals engaged in high-intensity physical training.
Methods: Forty-five patients (age 22.5 ± 4.
J Magn Reson Imaging
October 2024
Department of Radiology, University Medical Center Groningen, Groningen, The Netherlands.
Background: Cardiac magnetic resonance elastography (MRE) shows promise in assessing the mechanofunctional properties of the heart but faces clinical challenges, mainly synchronization with cardiac cycle, breathing, and external harmonic stimulation.
Purpose: To determine the reproducibility of in vivo cardiac multifrequency MRE (MMRE) for assessing diastolic left ventricular (LV) stiffness and viscosity.
Study Type: Prospective.
Comput Cardiol (2010)
October 2023
Scientific Computing and Imaging Institute, University of Utah, SLC, UT, USA.
Individual variability in parameter settings, due to either user selection or disease states, can impact accuracy when simulating the electrical behavior of the heart. Here, we aim to test the impact of inevitable uncertainty in conduction velocities (CVs) on the output of simulations of cardiac propagation, given three stimulus locations on the left ventricular (LV) free wall. To understand the role of physiological variability in CV in simulations of cardiac activation, we generated detailed maps of the variability in propagation simulations by implementing bi-ventricular activation simulations and quantified the effects by deploying robust uncertainty quantification techniques based on polynomial chaos expansion (PCE).
View Article and Find Full Text PDFAim: To evaluate the efficacy and safety of the advanced technique for positioning the endocardial electrodes of a cardiac contractility modulation (CCM) device.
Materials And Methods: The CCM system was implanted in 100 patients, of which 60 CCM electrodes were positioned in the most optimal zones of myocardial perfusion, in particular, in the zone of the minor focal-scar/fibrotic lesion (the Summed Rest Score of 0 to 1-2, the intensity of the radiopharmaceutical at least 30%), and in 40 patients according to the standard procedure. Before the implantation of the CCM system, 60 patients underwent tomography (S-SPECT) of the myocardium with Tc-methoxy-isobutyl-isonitrile at rest to determine the most optimal electrode positioning zones and 100 patients underwent transthoracic echocardiography at baseline and after 12 months to assess the effectiveness of surgical treatment.
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