Flashcards in Exam 4 Deck (107):
Where is the heart located?
What does the pericardial sac secrete and which part?
Serous fluid from parietal pericardium
If there is less contraction force, what happens to blood pressure?
What is cardiac tamponade?
Bleeding into pericardial cavity and a clot forms. To treat clot is scooped out and sealed off
Where is myocardium the thickest?
What allows for ionic charges in muscle cell?
What prevents cardiac muscle from tearing apart?
What are characteristics of cardiac muscle cells?
Branched, uninucleate, striated, and have intercalated discs with gap junctions
What all brings blood to right atrium?
Superior vena cava, inferior vena cava, and coronary sinus
What muscle is on the anterior heart wall?
What muscle is on posterior heart wall?
If blood goes in opposite direction what is that called?
A heart murmur
What do chordae tendinae do?
Close valves when pressure is on them
What muscle is on auricles?
What produces the sounds heard through a stethoscope?
Closing of valves
What do septal marginal trabeculae do?
Prevent ventricle from overfilling
What do moderator bands do?
Moderate the amount of stretch in the right ventricle. Allows for greater contraction depolarizing quicker
What valve causes the first sound of contraction?
What valves cause the second sound of contraction?
Semilunar valves closing
What are problems with prosthetic heart valves?
Thrombosis, infection, structural failure, dehiscence, disproportion
What is dehiscence
Separation from prosthetic valve suture line from the heart, leading to paravascular leakage
Disproption of heart valve is what?
Prosthetic valve may not fit well In heart, so blood flow is not optimal
Blockage to which artery leads to death?
Left anterior descending artery
What is the biggest factor in smaller BVs?
Pathway conduction system
SA node, AV node, AV bundle, right and left bundle branches, purkinje fibers
Function of AV node
Pauses conduction allowing atrium to complete contraction as blood goes ventricles. Causes about 100 msec delay
Once impulse reaches purkinje fibers, what happens?
Ventricular contraction begins
What is the QRS complex caused by?
What is the T wave caused by?
What is P wave represent?
What does Ach do?
Decreases heart rate
What connects to SA and AV node for sympathetic activation?
What do postganglionic fibers secrete?
What does epinephrine do and what is it secreted by?
Increases heart rate, strength of contraction, and cardiac output
The middle cerebral artery supplies which sulcus?
If there is a stroke in posterior cerebral artery what may be effected?
If there is a stroke in anterior cerebral artery what may be effected?
What are the 5 special fetal structures of the cardiovascular system?
Ductus arteriosus, foramen ovale, ductus venosus, umbilical vein, umbilical arteries
Fetal structure of ligamentum arteriosum?
Fetal structure of fossa ovalis
Fetal structure of ligamentum venosum
Fetal structure of ligamentum teres
Fetal structure of medial umbilical ligaments?
What is ventricular septal defect (VSD)
Hole in membranous or muscular portions of intraventricular septum that produces a left to right shunt, more severe with larger defects
What is atrial septal defect? (ASD)
Hole in interatrial septum produces a modest left to right shunt. Blue baby
Patent ductus arteriosus (PDA)
Ductus arteriosus remains open and left to right shunt develops
Tetralogy of fallot
Pulmonic stenosis results in right ventricular hypertrophy and right to left shunt across a VSD which has an overriding aorta
Transposition of great vessels
Aorta rises from right ventricle and pulmonic trunk from left ventricle. There is right to left shunting. VSD or ASD with PDA is needed for survival
What are the three layers of blood vessels superficial to deep
Adventitia, media, intima
Functions of heart
Transport O2, Transport nutrients, transport hormones, transport antibodies, transport waste to kidneys
What are capillaries?
Small thin walled vessels that interconnect arteries and veins
Where is the pericardial cavity?
In the mediastinum
What is fibrous pericardium made of?
Dense irregular CT
The serous pericardium includes what?
Visceral and parietal pericardium
What does pericardial fluid do?
Found within pericardial cavity, it reduces friction between opposing surfaces
What is epicardium made of?
What tissue makes up endocardium?
What do intercalated discs have that make them special?
Desmosomes connecting sarcolemma, fascia adherens which allows cells to pull with max efficiency, gap junctions
Why is cardiac muscle called a functional synctium?
Contraction of one cell causes contraction of others
Elasticity of pericardium may be reduced due to inflammation of pericardium
What kind of pericardium are valves?
What separates the right and left atria?
How long is foramen ovale present?
5th week until birth
If foramen ovale does not close what happens?
Efficiency of systemic circulation is reduced leading to cardiac enlargement, fluid buildup in lungs, and heart failure
What is the span of the moderator band?
From interventricular septum in right ventricle to bases of papillary muscles
What are the names for the left atrioventricular valve?
Mitral valve and bicuspid valve
Is there a moderator band in left ventricle?
What prevents aortic semilunar valve cusps from sticking to the wall of the aorta?
Aortic sinuses where right and left coronary arteries originate
For their contractions, which ventricle relies on the others pressure?
Right relies on left because of its thinner wall
What happens when the right ventricle contracts?
Distance between base and apex decreases and diameter of ventricular chamber decreases
What is the extensive connective tissue network that encircle base of pulmonary trunk and valves of the heart?
What are functions of the fibrous skeleton?
Stabilizing positions of muscle cells and valves. Providing physical support for cardiac muscle cells for blood vessels and nerves in myocardium, distribute forces of contraction, reinforcing valves preventing over expansion of heart, helping heart return to original shape after contraction, isolates atrial muscle cells from, ventricle muscle cells for coordination of contraction
Branches of which artery supply the sinoatrial node?
Interconnection between arteries/veins that keeps blood flow constant regardless of pressure fluctuations
What is an example of an anastomoses?
In the coronary circuit. Small branches from LAD to posterior interventricular artery
Partial or complete blockage of coronary arteries due to plaque
First symptoms of CAD. Insufficiency in delivery of oxygen when workload increases
What cells are responsible for conducting within the heart?
Nodal cells and pacemaker cells
What do conducting fibers do?
Distribute contractile stimulus to the general myocardium
What are nodal cells responsible for?
Establishing rate of heart contraction
Describe pacemaker cells
Usually reach threshold first and determine normal rate of contraction. Found in SA node
What is moderator bands role in conduction
Spreads impulse to papillary muscle in right ventricle
Where does left bundle branch deliver impulses to?
Where does right bundle branch deliver impulses to?
Where does purkinje fibers deliver impulses to?
Contractile cells of ventricular myocardium
What receptors relay information back to cardiac centers?
Baroreceptors (BP) and chemoreceptors(gas).
What innervates Baroreceptors and chemoreceptors?
Glossopharyngeal and vagus nerves
NE increases HR by binding to which receptors on what cells?
Beta receptors on nodal cells
Ach decreases heart rate by binding to which receptors on which cells?
Muscarinic receptors of nodal cells
Which layer of blood vessels does vasoconstriction and vasodilation?
Blood vessels in the walls of large vessels that supply smooth muscle cells, fibroblasts, and fibrocytes of media and adventitia
Largest type of artery. Can expand handling large volume of blood. Small density of smooth muscle cells in media
What are examples of elastic arteries?
Pulmonary trunk, aorta, common carotid, subclavian, common iliac artery
What are the three types of arteries?
Elastic arteries, muscular arteries, arteriole
Where do muscular arteries transport blood and what are examples?
Skeletal muscle and internal organs. Have a thicker media. External carotid, brachial artery, femoral artery, Mesenteric artery
Smaller arteries. Poor adventitia. Control blood flow between arteries and capillaries
Describe continuous capillaries
Complete epithelial lining connected by tight junctions and desmosomes. Found in most of the body
Describe fenestrated capillaries
Windows in endothelial lining. Allow molecules to pass through. Found in kidneys, endocrine organs
What are sinusoids?
Flattened and irregular. They follow the internal contours of complex organs. Found in liver, bone marrow, spleen, supra renal glands
What are atriovenous anastomoses?
Direct connections between arterioles and Venules. Found where changes in body position could alter blood flow
Where are arterial anastomoses found?
Brain, heart, stomach, and other organs needing a lot of blood supply
What is capillary autoregulation?
Pre capillary sphincters go through cycles of alternately contracting and blood flow in capillary occurs in pulses. Blood reaches Venules by one route now then another later
If pericardium becomes inflamed or infected, fluid accumulates
The CT of the epicardium and interventricular sulci?
What separates the atria and ventricles?
Coronary sulcus or atrioventricular sulcus
When the heart is rotated slightly to the left, what is the anterior surface called?