What are the horizontal ridges of muscle on the anterior wall of the right and left atria?
What is the vertical ridge of muscle that connects the pectinate muscles? What chamber of the heart?
Crista terminalis. Located in the R and L atria. Pectinate muscles on the anterior wall.
What heart chamber and wall has the opening to the superior vena cava?
Right atrium. Posterior wall.
What heart chamber and wall has the opening of the superior vena cava?
Right atrium. Posterior wall.
What heart chamber and wall has the opening and valve of the inferior vena cava?
Right atrium. Posterior wall.
What heart chamber and wall has the opening and valve of the coronary sinus?
Right atrium. Posterior wall.
What heart chamber and wall has the fossa ovalis?
What is the fossa ovalis? Right atrium. Posterior wall. Remnant of the foramen ovale, a fetal shunt from R atrium to L atrium.
What is the remnant of the foramen ovale, and what was it? Where located?
Fossa ovalis. Right atrium, posterior wall. In fetal circulation, blood from the placenta arrived in R atrium and was shunted to L atrium, bypassing the lungs.
What is the border of the fossa ovalis called?
Limbus fossa ovalis.
Where is the sinuatrial node?
At the junction between the R atrium and SVC. At the superior end of the crista terminalis.
Where is the atrioventricular node?
In the interatrial septum, above the opening of the coronary sinus.
What is the other name for the right atrioventricular valve? How many cusps?
Tricuspid valve. 3 cusps = anterior, posterior, septal.
What connects the right atrioventricular valve to the wall of the right ventricle?
1) papillary muscles arise from the wall of the ventricle. Anterior, septal, and posterior. 2) Chordae tendonae = delicate tendons that pass from the right atrioventricular cusps to the apices of the papillary muscles.
Where are the papillary muscles located?
Anterior, septal, and posterior in the right ventricle. Connect ventricle wall to the cusps of the tricuspid valve.
Where are the chordae tendinae located?
Connect the papillary muscles to the cusps of the tricuspid valve in the R ventricle, and the mitral valve in the left ventricle.
What are the muscles on the inner surface of the ventricles called?
Where are the trabeculae carnae located?
Muscular ridges that roughen the inner surface of the wall of the right and left ventricle.
What extends from the atrioventricular septum to the base of the anterior papillary muscle? What functional part does it contain?
Septomarginal trabecula = moderator band. Contains part of the right bundle, which is the part that stimulates the anterior papillary muscle.
Where is the opening of the pulmonary trunk located?
Where is the pulmonary valve located? How many cusps?
Right ventricle. 3 semilunar cusps = anterior, right, left.
What are the parts of the cusps of the pulmonary valve?
Each cusp has one fibrous nodule and 2 lunules, all of which help seal the valve cusps so there is no backflow of blood during diastole.
What is the conus arteriosus (infundibulum)? Where is it located?
Cone-shaped portion of the right ventricle inferior to the opening of the pulmonary trunk.
Where is the inner wall of the right atrium smooth, and where is it rough?
The inner wall of the conus arteriosus (cone shaped portion inferior to the pulmonary trunk opening) is smooth. The part with the trabeculae carnae is rough.
Where do the pulmonary veins connect to the heart? How many?
4 pulmonary veins connect to the left atrium.
Where is the valve of the foramen ovale located?
In the interatrial septum, on the side of the L atrium.
Where is the aortic valve located? How many cusps?
Left ventricle. Has 3 semilunar cusps = right, left, posterior.
What are the parts of the aortic valve? Anything notable?
Each cusp has 1 nodule and 2 lunules. The aortic sinuses are the pockets in the cusps. The right and left coronary arteries arise from the sinuses of the right and left cusps. The posterior cusp is thus the noncoronary cusp.
What is the left atrioventricular valve also called? How many cusps?
Bicuspid valve = mitral valve. Has an anterior and posterior cusp.
What is different about the papillary muscles on the right and left side of the heart?
On the right side, there are 3. Anterior, posterior, and septal, to connect with the 3 cusps of the tricuspid valve. On the left, there are only 2 papillary muscles (anterior and posterior) to connect to the 2 cusps of the mitral valve.
What are the parts of the interventricular septum and where are the parts located?
1) muscular part 2) membraneous part= located inferior to the attachment of the right cusp of the aortic valve.
How do electrical signals pass through the parts of the heart? Order?
1) SA node = in wall of the R atrium, superior end of crista terminalis, near SVC. 2) impulses from SA node pass thru wall of R atrium to AV node. (In the interatrial septum, above the opening of the coronary sinus.) 3) impulses from AV node pass thru the AV bundle in the membraneous part of the interventricular septum. 4) AV bundle divides into right and left bundles = on either side of the muscular part of the interventricular septum. Stimulates ventricles to contract!
What is the sinus venarum? What does it form? Where located?
It is the smooth part of the R atrium wall. Separated from the rest by the crista terminalis. Forms the SA node and the coronary sinus! Used to be the sinus venosus (btw SVC and IVC).
What is the portion of the left ventricle immediately inferior to the aortic orifice? What is special about its walls?
Aortic vestibule. Fibrous instead of muscular walls.
What kind of fibers make up the SA node? Where located?
Specialized cardiac muscle fibers, in the wall of the right atrium, superior wend of the crista terminalis, near the SVC opening.
What is the effect of sympathetic innervation of the SA node? Parasympathetic?
Sympathetic increases the heart rate, and parasympathetic decreases the rate.
What kind of fibers make up the AV node? Where located? From where does it receive impulses? And where does it distribute the impulses?
Specialized cardiac muscle fibers. In the interventricular septum. Receives impulses from both atria. Conducts impulses relatively slowly and distributes them to the AV bundle.
Where is the atrioventricular bundle (bundle of his)? From where does it receive its impulse, and where does it send the impulse?
Specialized cardiac muscle fibers in the interventricular septum. Then branches into left and right bundles. Right branch innervates the septal muscle, anterior papillary muscle, and wall of R ventricle. Left branch innervates septum, papillary muscles, and wall of L ventricle.
When do the papillary muscles contract, as compared to when the ventricles contract? Why?
The papillary muscles contract slightly before the ventricles so the cusps of the atrioventricular valves are held firmly in place. Prevents back flow.
What is the outer sac around the heart called? Where does it extend? Where is it notably anchored?
Fibrous pericardium. Cone-shaped bag extending from the diaphragm to the great vessels. Anchored in position because attachments involve fusion of fibers. And anchored to the posterior surface of the sternum, so the heart is anchored to the thorax.
What is the inner sac around the heart called? What are its special characteristics?
Serous pericardium. Double layered. Inner layer = epicardium = visceral portion. Covers the heart. Outer layer = parietal pericardium = lines the fibrous pericardium. 2 layers are continuous. The potential space between the parietal and visceral layers normally only contains a thin film of fluid to allow mvt.
Where is there potential space in the layers surrounding the heart?
Potential space between the visceral and parietal pericardium ( the 2 layers of the serous pericardium under the fibrous (outer) pericardium). Normally only a thin film of fluid between the 2 layers of serous pericardium, for mvt.
What is it called when there is a sudden insufficiency of arterial or venous blood supply? What does it cause in the heart wall?
Myocardial infarct. Results in a macroscopic area of necrosis in the muscular wall of the heart?
What is ischemia? What if there is ischemia of the heart muscle?
Ischemia = restriction of blood supply. Cardiac ischemia causes angina pectoris, severe pain in the chest that often radiates down the left arm. Usually caused by coronary disease. May precede a myocardial infarct.
What is it called when there is inflammation of the muscular walls of the heart?
What is it called when there is compression of venous return to the heart due to increased fluid volume in the pericardium?
What is it called when there is rapid beating of the heart? (Pulse over 100). What about slow beating (pulse under 60)?
tachycardia= fast beating. Bradycardia = slow beating.
What is it called when there are exceedingly rapid twitchings or contractions of heart muscle fibers? Why a problem?
Atrial or ventricular fibrillation. Very inefficient and must be stopped in order to have adequate blood flow.
What is atheroschlerosis?
One kind of arterioschlerosis (hardening of the arteries). Irregularly shaped lipid deposits in large and medium sized arteries.
What is it called when there is a progressive increase in muscle and elastic tissue of the arterial cells?
Hypertensive arterioschlerosis. One of the 2 kinds of arterioschlerosis (hardening of the arteries).
What is a stroke (cerebrovascular accident)?
Sudden neurological affliction resulting from a deficit in cerebral blood due to thrombosis, hemorrhage, or embolism.