WEEK 1 (Cardiac Anatomy) Flashcards
What does the anterior surface of the heart consist of?
- Mostly the right ventricle
- Right atrium
- Left ventricle
What is important about the heart in its anatomical position?
- Rests on the diaphragmatic surface
- Consists of LEFT VENTRICLE, small portion of the RIGHT VENTRICLE
- L&R VENTRICLE separated by the POSTERIOR INTERVENTRICULAR GROOVE
Left pulmonary surface
- Faces the left lung
- Broad & convex
- Consists of the LEFT VENTRICLE and a portion of the LEFT ATRIUM
Right pulmonary surface
- Faces the right lung
- Broad & convex
- Consists of the right atrium
Obtuse margin
- Separates the anterior and left pulmonary surfaces
- Round
- Extends from the left auricle to the cardiac apex
- Formed mostly by the LEFT VENTRICLE and a small portion of the LEFT AURICLE
Coronary Sulcus
- Circles the heart
- Separates atria from the ventricles
- Contains RIGHT CORONARY ARTERY, SMALL CARDIAC VEIN, CORONARY SINUS and CIRCUMFLEX BRANCH of the LEFT CORONARY ARTERY
Which two Sulci separate the two ventricles?
The anterior and posterior inter ventricular sulci
Anterior interventricular sulci
- Separates the two ventricles
- Anterior surface of the heart
- Contains anterior interventricular artery & great cardiac vein
Posterior interventricular sulci
- On the DIAPHRAGMATIC SURFACE OF THE HEART
- Contains the POSTERIOR INTERVENTRICULAR ARTERY and the MIDDLE CARDIAC VEIN
Function of the heart pumps
The RIGHT PUMP receives deoxygenated blood from the body and sends it to the lungs. The LEFT PUMP receives oxygenated blood from the lungs and sends it to the body.
[each pump consists of an ATRIUM and a VENTRICLE separated by a valve]
Function of Atria
Receive blood coming into the heart
Function of Ventricles
Pump blood out of the heart
Why is the muscular wall of the left ventricle thicker than the right?
More force is required to pump blood through the body than through the lungs
Blood returning to the Right atrium enters through one of three vessels, which are?
- SUPERIOR VENA CAVA
- INFERIOR VENA CAVA
[deliver blood to heart from body] - CORONARY SINUS
[returns blood from the walls of the heart itself]
Right atrioventricular orifice
- Where blood passes from the right atrium into the right ventricle
- Opening faces forward and medially
- Closed during ventricular contraction by the TRICUSPID VALVE
Sulcus terminalis cordis
- Shallow, vertical groove
- Externally indicates the division of the right atrium into two continuous spaces
- From the right side of the opening of the SUPERIOR VENA CAVA to the right side of the opening of the INFERIOR VENA CAVA
Crista terminalis
- Internally indicates the division of the right atrium into two continuous spaces
- Smooth, muscular ridge
Interatrial Septum
Separates the right from the left atrium
Right ventricle
- To the left of the RIGHT ATRIUM and is in front of and to the left of the ATRIOVENTRICULAR ORIFICE
- Outflow tract leading to pulmonary trunk is CONUS ARTERIOSUS
What are the three Papillary muscles in the right ventricle?
- Anterior papillary muscle
- Posterior papillary muscle
- Septal papillary muscle
Anterior papillary muscle
- Largest & most constant papillary muscle
- Arises from the anterior wall of the ventricle
Posterior papillary muscle
- Some CHORDAE TENDINEAE arising directly from the ventricular wall
- May consist of one, two or three structures
Septal papillary muscle
- Most inconsistent papillary muscle
- Chordae tendineae emerging directly from the septal wall
Tricuspid Valve
- The RIGHT ATRIOVENTRICULAR ORIFICE is closed during ventricular contraction by the TRICUSPID VALVE
- Three cusps: ANTERIOR, SEPTAL and POSTERIOR CUSPS
Describe the function of the Tricuspid valves
- During filling of the right ventricle, the tricuspid valve is open and the three cusps project into the right ventricle
- PAPILLARY MUSCLES and associated CHORDAE TENDINEAE keep the valves closed during contraction
- CHORDAE TENDINEAE from two PAPILLARY MUSCLES attach to each cusp which prevents separation during ventricular contraction
- Proper closing of the tricuspid valve causes blood to exit the right ventricle into the pulmonary trunk
Pulmonary Valve
- Closes the opening of the PULMONARY TRUNK from the RIGHT VENTRICLE
- Three SEMILUNAR CUSPS (Left, Right and Anterior Semilunar cusps)
- After ventricular contraction, the recoil of blood fills the PULMONARY SINUSES and forces the cusps closed preventing blood in the PULMONARY TRUNK from refilling the right ventricle
Left Atrium
POSTERIOR HALF (INFLOW PORTION):
- Receives the four pulmonary veins
- Smooth walls
- Derived from the proximal parts of the pulmonary veins that are incorporated into the left atrium during development
ANTERIOR HALF:
- Continuous with the left auricle
Valve of the Foramen Ovale
During development, VALVE OF THE FORAMEN OVALE prevents blood from passing from the left atrium to the right atrium. This valve may not be completely fused in some adults leaving a PROBE PATENT PASSAGE between the two atria
Left Ventricle
- Blood enters the ventricle through the LEFT ATRIOVENTRICULAR ORIFICE
- Longer than right ventricle
- Thickest layer of MYOCARDIUM
- TRABECULAE CARNEAE are fine and delicate in contract to those in the right ventricle
- ANTERIOR and POSTERIOR PAPILLARY MUSCLES are found in the left ventricle and are larger than those in the right ventricle
Mitral valve (Bicuspid valve)
- Left atrioventricular valve
- Two cusps: ANTERIOR and POSTERIOR CUSPS
Aortic Valve
- Continuous superiorly with the ASCENDING AORTA
- Opening from left ventricle into the AORTA is closed by the AORTIC VALVE
- Three SEMILUNAR CUSPS
- RIGHT, LEFT & POSTERIOR SINUSES between semilunar cusps and wall of ascending aorta
What are the two types of Valve disease?
- INCOMPETENCE = poorly functioning valves
- STENOSIS = narrowing of the orifice
What heart changes do stenosis and incompetence lead to?
- Left ventricular hypertrophy
- Increased pulmonary venous pressure
- Pulmonary edema
- Enlargement and hypertrophy of left atrium
Valve disease in the right side of the heart
- Caused by infection
- Produces abnormal pressure changes in the right atrium and right ventricle
- Cardiac failure
Cardiac Skeleton
- A collection of dense, fibrous connective tissue in the form of four rings with interconnecting areas in a plane between the atria and the ventricles
- FUNCTION: Helps maintain the integrity of the openings it surrounds and provides points of attachment for the cusps
Sinu-atrial node
- Where impulses begin (CARDIAC PACEMAKER)
- Collection of cells located at the superior end of the CRISTA TERMINALIS at the junction of the SUPERIOR VENA CAVA and the RIGHT ATRIUM
- Signals here spread across the ATRIA causing the muscle to contract
Atrioventricular node
- Stimulation caused by excitation of ATRIA
- Forms beginning of ATRIOVENTRICULAR BUNDLE which extends excitatory impulse to VENTRICLE MUSCLES
What is the autonomic division of the peripheral nervous system directly responsible for regulating?
- Heart rate
- Force of each contraction
- Cardiac output
What are the Tricuspid and Bicuspid Valve collectively called?
Atrioventricular Valves
