Heart Part 1 Flashcards
Which chamber of the heart has the thickest walls?
Left ventricle (2-3x more)
Which chamber of the heart has the thinnest walls?
Right atrium
What is a pulmonary embolism?
Obstruction of a pulmonary artery by a blood clot
What is the typical pathway of a pulmonary embolism?
Passes through the inferior or superior vena cava to the right atrium, then right ventricle, then pulmonary trunk, then pulmonary arteries where the block occurs
How can heart failure occur with a pulmonary embolism?
Dilation of the right ventricle and atrium can occur (death within minutes)
What three things do all of the heart valves have?
Valve orifice, fibrous ring (anulus), and cusps
Which two heart valves posses semilunar cusps?
Pulmonary and aortic valves
Which heart valve is the only one without 3 cusps?
Mitral (bicuspid) valve
What is the location of the pulmonary valve?
Between the right ventricle and pulmonary trunk
What is the location of the aortic valve?
Between the left ventricle and aorta
What is the location of the mitral (bicuspid) valve?
Between the left atrium and left ventricle
What is the location of the tricuspid valve?
Between the right atrium and right ventricle
What are the cusps of the pulmonary valve?
Anterior, left and right
What are the cusps of the aortic valve?
Left, right, and posterior
What are the cusps of the mitral (bicuspid) valve?
Anterior and posterior
What are the cusps of the tricuspid valve?
Anterior, posterior, and septal
What are the alternative names for the mitral and tricuspid valves?
Left and right atrioventricular valves, respectively
What causes the “lub” sound?
Contraction of the ventricles and closure of the tricuspid and mitral valves
What causes the “dup” sound?
Closure of the pulmonary and aortic valves
Where is the pulmonary valve most audible?
Over the left second intercostal space
Where is the aortic valve most audible?
Over the right second intercostal space
Where is the mitral valve most audible?
Over the left fifth intercostal space at the midclavicular line
Where is the tricuspid valve most audible?
Over the left fifth intercostal space at the border with the sternum
Which is the most frequently diseased valve?
Mitral valve
Which is the second most frequently diseased valve?
Aortic valve
Why is the mitral valve the most frequently diseased valve?
Due to the increased pressure generated by the left ventricle leading to microabrasions
What is the orientation of the heart?
From base to apex: forward, downward, and to the left (roughly a 45 degree angle)
What forms the base of the heart?
Left and right atria
What forms the apex of the heart?
Left ventricle
The apex of the heart lies in which intercostal space?
Left 5th
What forms the majority of the anterior surface of the heart?
Right ventricle
What forms the diaphragmatic surface of the heart?
Right and left ventricles
What mostly forms the left pulmonary surface of the heart?
Left ventricle
What mostly forms the right pulmonary surface of the heart?
Right atrium
What is the ear-like appendage from the superior aspect of the right atrium?
Right auricle
What are the prominent parallel ridges located in the anterior atrial wall?
Pectinate muscle
What is the vertical muscular ridge that runs from the opening of the superior vena cava to that of the inferior vena cava & marks the termination of the pectinate muscles?
Crista terminalis
What separates the right atrium proper from the sinus of vena cave?
Crista terminalis
What is the smooth-walled area located posterior to the crista terminalis that receives openings of the superior vena cava, inferior vena cava, coronary sinus, and anterior veins of the right ventricle?
Sinus of venae cavae
What is the remnant of the foramen ovale which is the opening between the right and left atrium that closes at birth?
Fossa ovalis
What is an atrial septal defect?
When the foramen ovale persists as a small opening in the superior part of the fossa ovalis
What is the rate of occurrence of atrial septal defect?
25% of adults
What is the term for minimal atrial septal defect?
Probe patent foramen ovale
What is the term for larger atrial septal defect?
Clinical atrial septal defect
What becomes dilated in atrial septal defect due to the blood being shunted from the left atrium to the right?
Right atrium, right ventricle, pulmonary trunk
What opening of the right atrium doesn’t have a valve?
Superior vena cava
What are the interconnecting muscular ridges located in the ventricular wall?
Trabeculae carneae
What are the cone-shaped muscles which originate from the ventricular wall that tend to be bifid, trifid, or multiple?
Papillary muscles
What attach the papillary muscles to the borders of the cusps of the tricuspid valve?
Chordae tendinae
What is significant about the chordae tendonae?
They prevent eversion of the valve during ventricular contraction
What is the upper portion of the right ventricle which ends in the pulmonary trunk?
Conus arteriosus
What is the thick, muscular ridge which separates the conus arterioles from the rest of the right ventricle?
Supraventricular crest
What is the large trabecular which extends from the inter ventricular septum to the base of the anterior papillary muscle?
Septomarginal trabecula (moderator band)
What are the two openings of the right ventricle?
Right atrium and pulmonary trunk
What is the ear-like appendage of the left atrium?
Left auricle
What is significant about the pectinate muscles of the left atrium?
Most of the left atrium wall is smooth due to fewer pectinate muscles
What are the two openings into the left atrium?
Pulmonary veins and left ventricle
What is significant about the trabecular carneae of the left ventricle?
Finer and more numerous
What is the aortic vestibule?
Smooth-walled portion of the left ventricle below the cusps of the aortic valve
What are the openings in the left ventricle?
Left atrium and aorta
What is the purpose of the septal wall?
Divides the heart into left and right halves
Which part of the septal wall is found between the two atria?
Interatrial septum
Which part of the septal wall is above the septal cusp of tricuspid valve and below the anterior cusp of mitral valve?
Atrioventricular septum
Which part of the septal wall is thin, smooth, and fibrous in structure?
Membranous interventricular septum
Which part of the septal wall is very think and no membranous like the rest?
Muscular interventricular septum
What are the two ways in which enlargement of the heart can occur?
Muscular hypertrophy or dilation of a chamber
Why does muscular hypertrophy of the heart occur?
To compensate for age, atherosclerosis, and/or hypertension when more force is required to push blood through the arteries
How does dilation of a heart chamber occur?
Septal defects and/or valve incompetency
What occurs with an incompetent mitral valve?
Regurgitation of blood from the left ventricle into the left atrium
Which valves lack chord tendineae and papillary muscles?
Pulmonary and aortic valves
What are the spaces between the semilunar cusps and the walls of the vessel called that are located superiorly?
Pulmonary and aortic sinuses
