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Heart Ventricles: The lower right and left chambers of the heart. The right ventricle pumps venous Blood into the Lungs and the left ventricle pumps oxygenated blood into the systemic arterial circulation.

Anatomy of the Heart

JoVE 10886

The human heart is made up of three layers of tissue that are surrounded by the pericardium, a membrane that protects and confines the heart. The outermost layer, closest to the pericardium, is the epicardium. The pericardial cavity separates the pericardium from the epicardium. Beneath the epicardium is the myocardium, the middle layer, and the endocardium, the innermost layer. There are four chambers of the heart: the right atrium, the right ventricle, the left atrium, and the left ventricle. These compartments have two types of valves—atrioventricular and semilunar—that prevent blood from flowing in the wrong direction. The right atrium receives blood from the coronary sinus and the superior and inferior vena cavae. This blood goes into the right ventricle via the right atrioventricular (or tricuspid) valve, a flap of connective tissue that prevents the backflow of blood into the atrium. Then, the blood leaves the heart, traveling through the pulmonary semilunar valve into the pulmonary artery. Blood is then carried back into the left atrium of the heart by the pulmonary veins. Between the left atrium and the left ventricle, the blood is again passed through an atrioventricular valve that prevents backflow into the atrium. This atrioventricular valve is called the bicuspid (or mitral) valve. The blood passes through the left ventricle into the aorta

 Core: Biology

Physiology of the Circulatory System- Concept

JoVE 10625

Homeostasis

Conditions in the external environment of an organism can change rapidly and drastically. To survive, organisms must maintain a fairly constant internal environment, which involves continuous regulation of temperature, pH, and other factors. This balanced state is known as homeostasis, which describes the processes by which organisms maintain their optimal internal…

 Lab Bio

Acquisition and Analysis of an ECG (electrocardiography) Signal

JoVE 10473

Source: Peiman Shahbeigi-Roodposhti and Sina Shahbazmohamadi, Biomedical Engineering Department, University of Connecticut, Storrs, Connecticut


An electrocardiograph is a graph recorded by electric potential changes occurring between electrodes placed on a patient's torso to demonstrate cardiac activity. An ECG signal…

 Biomedical Engineering

Cardiac Exam II: Auscultation

JoVE 10124

Source: Suneel Dhand, MD, Attending Physician, Internal Medicine, Beth Israel Deaconess Medical Center


Proficiency in the use of a stethoscope to listen to heart sounds and the ability to differentiate between normal and abnormal heart sounds are essential skills for any physician. Correct placement of the stethoscope on the chest…

 Physical Examinations I

The Cardiac Cycle

JoVE 10887

The heart beats rhythmically in a sequence called the cardiac cycle—a rapid coordination of contraction (systole) and relaxation (diastole).

Electrical signals—sent from the sinoatrial (SA) node in the right atrial wall to the atrioventricular (AV) node between the right atrium and right ventricle—cause both atria to simultaneously contract. When the signal reaches the AV node, it pauses for approximately a tenth of a second, allowing the atria to contract and empty blood into the ventricles before they contract. The electrical impulses are then conducted by the bundle of His and propagated to the left and right bundle branches. The signal is then conducted by Purkinje fibers in the ventricular walls, inducing ventricular contraction and pumping blood out of the heart. During diastole (relaxation), the heart fills with blood, and the cycle is repeated.

 Core: Biology

Pericardiocentesis

JoVE 10236

Source: Rachel Liu, BAO, MBBCh, Emergency Medicine, Yale School of Medicine, New Haven, Connecticut, USA


The heart lies within the pericardium, a relatively inelastic fibrous sac. The pericardium has some compliance to stretch when fluid is slowly introduced into the pericardial space. However, rapid accumulation overwhelms pericardial…

 Emergency Medicine and Critical Care

Diagnostic Necropsy and Tissue Harvest

JoVE 10294

Source: Kay Stewart, RVT, RLATG, CMAR; Valerie A. Schroeder, RVT, RLATG. University of Notre Dame, IN


Many animal experiments rely on final data collection time points that are gathered from the harvesting and testing of organs and tissues. The use of appropriate methods for the collection of organs and tissues can impact the quality of…

 Lab Animal Research

Computational Fluid Dynamics Simulations of Blood Flow in a Cerebral Aneurysm

JoVE 10479

Source: Joseph C. Muskat, Vitaliy L. Rayz, and Craig J. Goergen, Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana


The objective of this video is to describe recent advancements of computational fluid dynamic (CFD) simulations based on patient- or animal-specific vasculature. Here,…

 Biomedical Engineering

High-frequency Ultrasound Imaging of the Abdominal Aorta

JoVE 10397

Source: Amelia R. Adelsperger, Evan H. Phillips, and Craig J. Goergen, Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana


High-frequency ultrasound systems are used to acquire high resolution images. Here, the use of a state-of-the-art system will be demonstrated to image the morphology and …

 Biomedical Engineering
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