Heart Structure, Function and Arrhythmias
Elizabeth M. Cherry and Flavio H. Fenton
Department of Biomedical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY
http://thevirtualheart.org
This document has three purposes.
First, it provides information about the heart's function and structure along with information about some
arrhythmias using interactive visualization techniques.
Second, it demonstrates how 3D PDF files can be used to include not only images or movies but also
interactive three-dimensional structures that can be manipulated by users to personalize their reading
experience.
Third, it shows an example of the future of documents. Many magazines and scholarly journals will benefit
from inclusion of interactive three-dimensional visualizations in the future.
Introduction.
The heart is a powerful muscle that pumps
blood throughout the body by means of a
coordinated contraction. The contraction is
generated by an electrical activation, which is
spread by a wave of bioelectricity that
propagates in a coordinated manner
throughout the heart. Under normal conditions,
the sinoatrial node initiates an electrical
impulse that propagates through the atria to
the atrioventricular node, where a delay
permits ventricular filling before the electrical
impulse proceeds through the specialized
His-Purkinje conduction system that spreads
the electrical signal at speeds of meters per
second throughout the ventricles. This
electrical impulse propagates diffusively
through the heart and elevates the voltage at
each cell, producing an action potential, during
which a surge in intracellular calcium initiates
the mechanical contraction. The normal
rhythm is altered when one or more spiral
(reentrant) waves of electrical activity appear.
These waves are life-threatening because they
Figure 1. The Heart. This is an interactive 3D heart. act as high-frequency sources and underlie
Click in the window to interact with it. The heart can complex cardiac electrical dynamics such as
be rotated, zoomed and panned by using the tachycardia and fibrillation. In the following
mouse as indicated in the figure. In addition, pages we describe in more detail the
pre-defined animations can be played by clicking heart's structure and function and illustrate
the "Explore" and "Spin" buttons. The object light, some of these lethal arrhythmias with
background and other properties can be changed movies and interactive 3D animations.
by using the menu that appears on the top of the
figure once it has been activated.
, Heart Anatomy and Structure
Figure 2 is a 3-D interactive heart. As you read about the heart’s components, click on their names in the list to
identify and visualize them.
Heart: A powerful muscle slightly larger than a clenched fist. It is composed of four chambers, two upper (the
atria) and two lower (the ventricles). It works as a pump to send oxygen-rich blood through all the parts of the
body. A human heart beats an average of 100,000 times per day. During that time, it pumps more than 4,300
gallons of blood throughout the entire body.
Right Ventricle: The lower right chamber of the heart. During the normal cardiac cycle, the right ventricle
receives deoxygenated blood as the right atrium contracts. During this process the pulmonary valve is closed,
allowing the right ventricle to fill. Once both ventricles are full, they contract. As the right ventricle contracts, the
tricuspid valve closes and the pulmonary valve opens. The closure of the tricuspid valve prevents blood from
returning to the right atrium, and the opening of the pulmonary valve allows the blood to flow into the pulmonary
artery toward the lungs for oxygenation of the blood
The right and left ventricles contract simultaneously; however, because the right ventricle is thinner than the left,
it produces a lower pressure than the left when contracting. This lower pressure is sufficient to pump the
deoxygenated blood the short distance to the lungs.
Left Ventricle: The lower left chamber of the heart. During the normal cardiac cycle, the left ventricle receives
oxygenated blood through the mitral valve from the left atrium as it contracts. At the same time, the aortic valve
leading to the aorta is closed, allowing the ventricle to fill with blood. Once both ventricles are full, they
contract. As the left ventricle contracts, the mitral valve closes and the aortic valve opens. The closure of the
mitral valve prevents blood from returning to the left atrium, and the opening of the aortic valve allows the blood
to flow into the aorta and from there throughout the body. The left and right ventricles contract simultaneously;
however, because the left ventricle is thicker than the right, it produces a higher pressure than the right when
contracting. This higher pressure is necessary to pump the oxygenated blood throughout the body.
To display the herat's
component click on the
names below
Figure 2. Interactive 3D heart structure. Click on the names on the right to display the components. Clicking
"Set View" first is recommended for a better visualization of the parts. The buttons below the figure allow
rotation and visualization of the structures in other modes, such as solid objects or sketches.
Elizabeth M. Cherry and Flavio H. Fenton
Department of Biomedical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY
http://thevirtualheart.org
This document has three purposes.
First, it provides information about the heart's function and structure along with information about some
arrhythmias using interactive visualization techniques.
Second, it demonstrates how 3D PDF files can be used to include not only images or movies but also
interactive three-dimensional structures that can be manipulated by users to personalize their reading
experience.
Third, it shows an example of the future of documents. Many magazines and scholarly journals will benefit
from inclusion of interactive three-dimensional visualizations in the future.
Introduction.
The heart is a powerful muscle that pumps
blood throughout the body by means of a
coordinated contraction. The contraction is
generated by an electrical activation, which is
spread by a wave of bioelectricity that
propagates in a coordinated manner
throughout the heart. Under normal conditions,
the sinoatrial node initiates an electrical
impulse that propagates through the atria to
the atrioventricular node, where a delay
permits ventricular filling before the electrical
impulse proceeds through the specialized
His-Purkinje conduction system that spreads
the electrical signal at speeds of meters per
second throughout the ventricles. This
electrical impulse propagates diffusively
through the heart and elevates the voltage at
each cell, producing an action potential, during
which a surge in intracellular calcium initiates
the mechanical contraction. The normal
rhythm is altered when one or more spiral
(reentrant) waves of electrical activity appear.
These waves are life-threatening because they
Figure 1. The Heart. This is an interactive 3D heart. act as high-frequency sources and underlie
Click in the window to interact with it. The heart can complex cardiac electrical dynamics such as
be rotated, zoomed and panned by using the tachycardia and fibrillation. In the following
mouse as indicated in the figure. In addition, pages we describe in more detail the
pre-defined animations can be played by clicking heart's structure and function and illustrate
the "Explore" and "Spin" buttons. The object light, some of these lethal arrhythmias with
background and other properties can be changed movies and interactive 3D animations.
by using the menu that appears on the top of the
figure once it has been activated.
, Heart Anatomy and Structure
Figure 2 is a 3-D interactive heart. As you read about the heart’s components, click on their names in the list to
identify and visualize them.
Heart: A powerful muscle slightly larger than a clenched fist. It is composed of four chambers, two upper (the
atria) and two lower (the ventricles). It works as a pump to send oxygen-rich blood through all the parts of the
body. A human heart beats an average of 100,000 times per day. During that time, it pumps more than 4,300
gallons of blood throughout the entire body.
Right Ventricle: The lower right chamber of the heart. During the normal cardiac cycle, the right ventricle
receives deoxygenated blood as the right atrium contracts. During this process the pulmonary valve is closed,
allowing the right ventricle to fill. Once both ventricles are full, they contract. As the right ventricle contracts, the
tricuspid valve closes and the pulmonary valve opens. The closure of the tricuspid valve prevents blood from
returning to the right atrium, and the opening of the pulmonary valve allows the blood to flow into the pulmonary
artery toward the lungs for oxygenation of the blood
The right and left ventricles contract simultaneously; however, because the right ventricle is thinner than the left,
it produces a lower pressure than the left when contracting. This lower pressure is sufficient to pump the
deoxygenated blood the short distance to the lungs.
Left Ventricle: The lower left chamber of the heart. During the normal cardiac cycle, the left ventricle receives
oxygenated blood through the mitral valve from the left atrium as it contracts. At the same time, the aortic valve
leading to the aorta is closed, allowing the ventricle to fill with blood. Once both ventricles are full, they
contract. As the left ventricle contracts, the mitral valve closes and the aortic valve opens. The closure of the
mitral valve prevents blood from returning to the left atrium, and the opening of the aortic valve allows the blood
to flow into the aorta and from there throughout the body. The left and right ventricles contract simultaneously;
however, because the left ventricle is thicker than the right, it produces a higher pressure than the right when
contracting. This higher pressure is necessary to pump the oxygenated blood throughout the body.
To display the herat's
component click on the
names below
Figure 2. Interactive 3D heart structure. Click on the names on the right to display the components. Clicking
"Set View" first is recommended for a better visualization of the parts. The buttons below the figure allow
rotation and visualization of the structures in other modes, such as solid objects or sketches.
