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Noninvasive Diagnosis Using Sounds Originating from within the Body
Published in Robert B. Northrop, Non-Invasive Instrumentation and Measurement in Medical Diagnosis, 2017
Another cardiac defect that can be diagnosed by hearing the S2 sound “split” is a left or right bundle branch block. The synchronization of the contraction of the muscle of the left and right ventricles is accomplished by the wave of electrical depolarization that propagates from the AV node, down the bundle of His, which bifurcates into the left and right bundle branches which run down on each side of the ventricular septum. Near the apex of the heart, the bundle branches branch extensively into the Purkinje fibers which invade the inner ventricular cardiac muscle syncytium, carrying the electrical activity that triggers ventricular contraction. See Figure 3.7 for a schematic, cut-away view of the heart, and Figure 3.8 for a time-domain schematic of where certain heart sounds occur in the cardiac cycle.
Introduction
Published in Laurence J. Street, Introduction to Biomedical Engineering Technology, 2016
Signals originate in the sinoatrial (SA) node. These signals cause the atria to contract, and are also carried to the atrioventricular (AV) node. From the AV node, action potentials travel down a bundle of fibers called the AV bundle or the bundle of His. This splits into left and right bundle branches, which in turn split into Purkinje fibers, or subendocardial fibers, which ultimately deliver the signals to the ventricular muscles.
Low-regret optimal control for an inverse electrocardiological problem with incomplete data
Published in International Journal of Control, 2023
Located between the lungs, the heart pumps blood from the lungs and the body and ejects it towards the whole body allowing the organs to operate thanks to the electrical conduction which can be defective, causing the heartbeat to be too fast, too slow or irregular. Some pathologies, as, for example, sinus node dysfunction or bundle branch block, are treated with an artificial pacemaker, which is used to help the heart to recover a quasi-normal electrical activity (see , for example, Jones et al., 2010, chap. 6, and the related article by Knight, 1972). Yet the use of artificial materials do not permit a direct access to the evaluation of the heart transmembrane potential without invasive intervention.