Chapter 26 Heart Flashcards
What are the layers of the heart?
- Pericardium
- Myocardium
- Endocardium
Where does the fibrous pericardium (external most layer of heart) connect to superiorly and inferiorly?
- Superiorly: blends with major blood vessels of the heart, vena cava, aorta, pulmonary vessels
- Inferiorly: blends with the central tendon of the diaphragm
What are auricles?
earlike appendages; attached laterally to the atria
What is the function of the auricles?
increase capacity of the atrium
What artery does the left coronary artery branch into?
- The anterior interventricular artery (left anterior descending artery)
- Circumflex branch
What artery does the right coronary artery branch into?
- Marginal branch
- Posterior interventricular artery
Where does the SVC, IVC, and coronary sinus drain into?
Right atrium
Where can a papillary muscle be found?
Attached to chordae tendinae
Where can a chordae tendinae be found and what type of valve is it associated with?
Attached to the lower surface of the cusps; AV valve
Trace the blood route through the heart starting with the SVC, IVC, and Coronary sinus and ending with the descending aorta.
Blood is deoxygenated
SVC –> IVC –> coronary sinus –> right atrium –> Right AV valve/tricuspid –> right ventricle –> pulmonary SL valve –> pulmonary trunk –> pulmonary arteries –> lungs
Blood is oxygenated
Lungs –> pulmonary veins –> left atrium –> left AV valve/bicuspid/mitral –> left ventricle –> aortic SL valve –> ascending aorta –> aortic arch –> descending aorta
Which chamber’s wall is the thickest?
Left ventricle
What artery supplies the breast?
- Internal thoracic artery (Principal blood supply to the breast; about 50%)
- Lateral thoracic artery
- Intercostal arteries
Where do the coronary arteries originate from?
- Right coronary artery: right aortic sinus
- Left coronary artery: left aortic sinus
How many cusps does each valve of the heart have?
- Bicuspid (mitral, left AV) valve: 2 cusps
- Tricuspid (right AV) valve: 3 cusps
- Aortic SL valve: 3 cusps
- Pulmonary SL valve: 3 cusps
What is the fossa ovalis?
Oval depression; located in right atrium
What is the foramen ovale?
A foramen that existed between the right and left atrium in the fetal stage; closes at birth and remains in an adult as the fossa ovalis
What is the ligamentum arteriosum?
A cord-like band that connects the pulmonary trunk and aortic arch
What area does the coronary sinus drain?
Drains deoxygenated blood into right atrium
What area does the IVC drain?
Lower half of the body
What area does the SVC drain?
Upper half of the body
What is musculi pectinati? Where is it found?
Muscular ridge-like extensions; In the auricular portion of the right atrium
What is trabeculae carnae? Where is it found?
Internal muscular ridge-like folds; In the inner surface of the right and left ventricle
Create a pathway of the electrical conduction of the heart starting with the sinoatrial node.
- SA node
- AV node
- AV bundle (bundle of His)
- left and right bundle branches
- Purkinje fibres
Discuss the location of each of the structures involved in electrical conduction
- SA node: Between the superior vena cava and the right atrium
- AV node: In the upper part of the interventricular septum
- AV bundle (bundle of His): Extends down into the interventricular septum
- left and right bundle branches: Interventricular septum
- Purkinje fibres: Inner ventricular walls of the heart; beneath the endocardium
Which structure of the heart is known as the pacemaker?
SA node
What is the moderator band?
A band that attaches to the interventricular septum and to the anterior papillary muscle
What is the interventricular septum?
The wall between the right and left ventricles
What is the interatrial septum?
The division between the right and left atrium
What structure(s) help protect the heart anteriorly and posteriorly?
- Anteriorly: Sternum
- Posteriorly: Thoracic vertebrae
Where can the apex of the heart be found?
At the level of the left sixth costal cartilage
