Term
| What is the equation for Ohm's Law of Hydrodynamics? |
|
Definition
Delta P= F X R
=>Delta P= change in P across the length of the vessel
=>F= flow (V/t)
=>R=resistance |
|
|
Term
| What is the equation for the Bulk Flow Law? |
|
Definition
F= delta P/R
=>F= flow
=>delta P= change in P across the length of the vessel
=>R= resistance |
|
|
Term
| What is the equation for calculating pulse pressure? |
|
Definition
| Systolic Pressure- Diastolic Pressure (mmHg) |
|
|
Term
| What is the equation for Mean Arterial Pressure? |
|
Definition
| MAP= P(diastolic) + (1/3) (Psystolic-Pdiasolic) |
|
|
Term
| Describe the relationship between flow, pressure, and resistance. |
|
Definition
|
|
Term
| How does vessel diameter affect resistance? How do changes in resistance affect flow? |
|
Definition
| Vessel diameter dec= R ic= Flow dec |
|
|
Term
| What type of vessels have the largest drop in pressure as the blood moves through the circulatory system? Why? |
|
Definition
-arterioles
-due to having the highest resistance as compared to the following capillary beds |
|
|
Term
| Why is the resistance of a capillary bed lower than that of the arterioles that supply it? |
|
Definition
| -because capillary beds as a whole have a cumulatively smaller resistance |
|
|
Term
| Definition: Driving Pressure |
|
Definition
| -the pressure that pushes blood through the vessels |
|
|
Term
| Definition: Hydrostatic Pressure |
|
Definition
| -in vessels that are vertical (changes with body position) force due to gravity |
|
|
Term
| Definition: Transmural Pressure |
|
Definition
=>P intravascular-P tissue
-pressure drop across the vessel wall |
|
|
Term
|
Definition
-a bullet-shaped profile in straight lines per level, idealized that the middle is the fastest due to least friction
-ideally silent |
|
|
Term
Definition: Turbulent Flow
-when does this clinically occur? |
|
Definition
-irregular, mixing flow of blood
-lots of E wasted, inc P, inc workload on heart
-occurs in bifurcations and stenosis |
|
|
Term
| Is laminar or turbulent flow noisy? |
|
Definition
|
|
Term
| Name 3 factors that tend to produce turbulent flow. |
|
Definition
| -vessel radius inc=inc turbulence -density inc= turbulene inc -viscosity inc= turbulence dec |
|
|
Term
| Definition: Systolic Pressure |
|
Definition
| -max ventricular P during contraction |
|
|
Term
| Definition: Diastolic Pressure |
|
Definition
| -min ventricular P during relaxation |
|
|
Term
| Definition: Mean Arterial Pressure |
|
Definition
| -mean pressure in arteries over time, area under the curve spends more time in diastole than systole |
|
|
Term
| What do we use to indirectly find blood pressure? How is it used? |
|
Definition
-sphygmomanometer
-cuff wrapped around limb/tail over an artery and pressurized to occlude flow=> pressure slowly released while flow is monitored=> expressed in mmHg as a difference from atmospheric P |
|
|
Term
| How is blood pressure directly measured? What are the downfalls of this method? |
|
Definition
-catheter with pressure transducer in vessel
-downfalls: invasive and technically demanding |
|
|
Term
| Between indirect and direct measurement of blood pressure, which is more accurate? |
|
Definition
|
|
Term
|
Definition
| -frictional resistance of layers within a fluid to flow |
|
|
Term
| How do changes in viscosity affect resistance? How does this affect flow? |
|
Definition
| viscosity inc= resistance inc= flow dec |
|
|
Term
| Give an example of a situation in which blood viscosity can change. |
|
Definition
| -when blood cells interact, like in clotting |
|
|
Term
| Fibrinogen interacts with RBCs in response to what clinical symptom? |
|
Definition
|
|
Term
|
Definition
| -friction of blood exerted on the vessel wall |
|
|
Term
| How do changes in vascular diameter affect R and flow through the affected vessel? |
|
Definition
| inc vascular diameter= dec R= inc flow |
|
|
Term
| Definition: Hydrostatic Pressure Difference |
|
Definition
| -difference between capillary P and interstitial P |
|
|
Term
| Definition: Colloid Osmotic Pressure |
|
Definition
| -pressure equivalent of the osmotic force exerted by protein (oncotic pressure) |
|
|
Term
| Is hydrostatic P constant along the length of the capillary? How about colloid osmotic P? |
|
Definition
-Hydrostatic changes
-Colloid osmotic remains constant |
|
|
Term
Definition: Net filtration pressure
-how does it affect absorption/filtration in capillaries? |
|
Definition
-combined influences of hydrostatic P and osmotic P
-when pos: fluid is filtered out of capillary
-when neg: fluid is reabsorbed into the capillary |
|
|
Term
| What are the 3 main types of vessels? |
|
Definition
-Smallest arterioles: smalles branches of arteries, control entry of blood to capillary beds, diameter is highly regulated
-Capillaries: smallest, no SMC, only one layer of endothelium
-Smallest venules: merge to form veins, low P, allow leukocyte diapedesis |
|
|
Term
| In what ways is the flow in capillaries different from flow in other vessels? |
|
Definition
-not constant: periodic opening (via closing of precapillary sphincters)
-flow dep on arteriole R |
|
|
Term
|
Definition
| -periodic opening and closing of precapillary sphincter to control blood flow in the capillaries |
|
|
Term
| What are precapillary sphincters located? |
|
Definition
|
|
Term
| How is the open/closed state of capillaries regulated? |
|
Definition
-metabolic control (via local control with molecules)
-myogenic control (control stretch)
-Autoregulation |
|
|
Term
| Name two arterial constrictors |
|
Definition
-Vasopressin
-Angiotensin II |
|
|
Term
| Describe the neural control of arterial pressure |
|
Definition
-sympathetically innervated
=>Adrenergic receptorsG-protein coupled
A1 :causes constriction, NE > EPI; IP3/Ca2+
B2 : EPI (adrenal gland); cAMP, causes relaxation (fight or flight/ adrenal medulla)
=> Cholinergic receptors:
Acetylcholine induces vasodilation; nitric oxide dependent
***Quick rule: 1 – excitatory; 2 – inhibitory
-Endothelium-derived substances: NO |
|
|
Term
| Give a few examples of molecular changes that would produce vasodilation |
|
Definition
-dec O2
-inc CO2
-inc lactinic/carbonic acids
-inc K (Na/K ATPase can't restore gradient fast enough)
-inc osmolarity (inc metabolite levels)
-inc adenosine (breakdown of ATP) |
|
|
Term
| Definition: Active Hyperemia |
|
Definition
| -tissue becomes more active, thus metabolic subs inc or dec, thus inc blood flow |
|
|
Term
| Definition: Reactive Hyperemia |
|
Definition
| -tissue at resting state and block off blood flow into tissue, thus waste products not removed, then release all of a sudden and blood flow increases to wach out build-up |
|
|
Term
| How do most brain capillaries differ from typical continuous capillaries? |
|
Definition
| -do not have spaces b/n endothelial cells due to the presence of tight junction (BBB) -does not allow AAs, Gluc, Hormones, cytokines, proteins, and some drugs |
|
|
Term
| Only ______-soluble substances cross the wall of all capillaries. |
|
Definition
|
|
Term
| Name some common physiological examples of lipid-soluble substances. |
|
Definition
| -O2, CO2, FAs, hormones, drugs |
|
|
Term
| What are the 3 types of capillaries? Structurally describe them |
|
Definition
1) continuous: lipid soluble
-has channels for water-soluble (Na, K, Gluc)
-plasma proteins trapped outside
-uses transcytosis (vesicles) for proteins
2) fenestrated and discontinuous/sinusoidal: have holes across walls that allow rapid diffusion of water and solutes
-liver capillaries: allows proteins to cross (albumin and clotting factors)
-bone marrow allows newly formed RBCs
3) Capillaries of BBB: have tight junctions and only allow lipid-soluble substances |
|
|
Term
|
Definition
| -fluid moves out of capillaries |
|
|
Term
|
Definition
| -fluid moves into capillaries |
|
|
Term
| Does a hydrostatic pressure difference favor fluid movement into or out of the capillary? A colloid osmotic pressure difference? |
|
Definition
-hydrostatic: out of capillary
-colloid: into capillary |
|
|
Term
| How does an increase in hydrostatic pressure affect fluid movement across capillary walls? An increase in colloid osmotic pressure? |
|
Definition
-inc H= inc filtration out of
-inc C: inc reabsorption |
|
|
Term
| What are the functions of the lymphatic system (4)? |
|
Definition
-removes fluid not reabsorbed by capillaries
-prevents fluid accumulation in interstitium
-returns protein lost from blood
-a "second circulation" without a central pump |
|
|
Term
| How much fluid does the lymphatic system filter a day? The capillary system? |
|
Definition
-Lymph: 3L/day
-Capillary: 17L/day |
|
|
Term
| What are the 4 main causes of edema? |
|
Definition
-inc capillary hydrostatic Pc
-dec capillary colloid osmotic PIc
-dec lymphatic drainage
-inc capillary permeability |
|
|
Term
| What causes right-sided heart failure? What happens during this issue? What kind of edema does this cause? |
|
Definition
-RV doesn't empty effectively=> blood backs up in vena cava=> peripheral capillaries have inc P
-causes peripheral edema |
|
|
Term
| What causes left-sided heart failure? What happens during this issue? What kind of edema does this cause? |
|
Definition
-LV doesn't empty effectively=> blood backs up in pulmonary vein=> lung capillaries have in P
-causes pulmonary edema |
|
|
Term
| What factors affect diffusion rate? |
|
Definition
-concentration gradient inc= inc DR
-O2 higher in capillary
-CO2 higher in tissue (opposite in pulmonary tissue)
-SA inc= inc DR
-MW of solute inc= dec DR
-diffusion distance inc= dec DR |
|
|
Term
| How do you calculate hematocrit? |
|
Definition
| Hematocrit= ht of RBCs/ total ht |
|
|
Term
Definition: Plasma
-does it require anticoagulant? |
|
Definition
-fluid component of blood,
-YES, draw blood with anticoagulant |
|
|
Term
|
Definition
| -fluid remaining after clot formation, draw blood without anticoagulant |
|
|
Term
| Which organ synthesizes the majority of plasma proteins? |
|
Definition
| -liver (albumin most common, fibrinogen becomes clotting factors, etc) |
|
|
Term
| What are the clinical consequences of decreased plasma protein levels that occur secondary to damage to that organ (2)? |
|
Definition
|
|
Term
| What is the major protein contained in erythrocytes? What is its function? |
|
Definition
| -Hemoglobin: binds O2 for transport |
|
|
Term
| What hormone stimulates erythrocyte production? Where is it synthesized? |
|
Definition
| -Erythropoietin -kidney and liver |
|
|
Term
| What is erythropoietin's site of action? |
|
Definition
| -sitmulates inc RBC pdn in bone marrow |
|
|
Term
| How are erythropoietin levels regulated? |
|
Definition
| -O2 levels are monitored by kidney, thus when O2 levels are too low, erythropoietin is stimulated to make more RBCs |
|
|
Term
| Heme is degraded to _______ in the _______. It is secreted in ________ and is further metabolized by _____ bacteria. |
|
Definition
-bilirubin
-liver
-bile
-gut |
|
|
Term
| What is the clinical manifestation of impairments to the heme degradation process? |
|
Definition
|
|
Term
| What are two possible ways that the heme degradation process could be impaired? CARD NOT FINISHED |
|
Definition
| -Liver damage: bilirubin not removed from circock bile duct: bilirubin not secreted to gut -Bl |
|
|
Term
| What are the 3 main types of circulating blood cell types? Relative abundance? Relative sizes? |
|
Definition
-RBCs: erythrocytes, most numerous, very small (large in avians)
-WBCs: Leukocytes, least numerous, larger than RBCs (same in avians)
-Platelets: thrombocytes, second most numerous, smallest |
|
|
Term
| How do leukocytes reach their site of action within tissues? |
|
Definition
| -interact with endothelial cell (act via inflammation), will secrete cell attachment proteins, leukocytes adhere to these proteins and roll along wall until they reach a gap in endothelium to get into tissues |
|
|
Term
| Where are platelets formed? From what precursor cell type? |
|
Definition
-bone marrow
-megakaryocytes |
|
|
Term
| What hormone regulates platelet production? What is its site of synthesis? How is its levels regulated? |
|
Definition
-thrombopoietin
-produced in liver
-stimulates pdn of and differentiation of megakaryocytes |
|
|
Term
| Name key platelet structures and functions (6) |
|
Definition
-Microtubules: under mem to change shape
-Mit: gen E
-Glycogen: sub for mit
-Open Canalicular System: mem invaginations to inc SA
-Dense granules: storage site for biochem mediators (ATP<ADP), serotonin Ca -Alpha Granules: storage site for proteins (clotting proteins like fibrinogen, vWF, Factor V), albumin growth factors (PDGF, TGF-beta, VEGF) |
|
|
Term
| Name the two main mechanisms for producing hemostasis. Which is needed for larger repairs? |
|
Definition
-Platelet plug formation: small holes
-Clotting: larger repairs |
|
|
Term
| How do platelets change shape when activated? What happens to platelet granules? |
|
Definition
-send out pseudopods to become spiky, contractile proteins contract
-granules move towards center of platelet, fuse with open canalicular system and released outside of cells |
|
|
Term
| Platelet activation is _____ dep and activated by _____ and _____ |
|
Definition
|
|
Term
| Name the two clotting pathways that converge one the common pathway. How are they activated? |
|
Definition
-Intrinsic: act by contact by neg charged surfaces (act platelets)
-Extrinsic: act by Factor III/ tissue thromboplastic (expressed on nonvascular cells) |
|
|
Term
| What is the key event in the common pathway of the clotting cascade? |
|
Definition
| -thrombin generation by conversion of Fibrinogento Fibrin |
|
|
Term
| What is the function of Thrombin? How does this occur? |
|
Definition
-functions as a procoagulant and anticoagulant
-pro activities platelets through its receptor on the platelets
-regulates its own generation by activating coagulation factors resulting in a burst of thrombin
-also stimulatesfibrinogen to fibrin, but also effects the cross-hooking of fibrin monomers to produce a firm fibrin clot |
|
|
Term
| What role does Vitamin K play in blood clotting? |
|
Definition
| -required cofactor for several clotting factors |
|
|
Term
| How does anticoagulant rat poison act? |
|
Definition
| -prevent regeneration of active vitamin K |
|
|
Term
| List and describe 3 causes of abnormal clotting function. |
|
Definition
-Factor VIII deficiency: Hemophilia A (dogs, cats, horses, cattle), X-linked recessive trait
-Factor IX deficiency: hemophilia B (dogs, cats)
-Von Willebrand's disease: defective von Willebrand factor (dogs, cats, pigs) delayed bleeding after injury due to poor adhesion of platelet aggregates to EC |
|
|
Term
| What are the key functions of the cardiovascular system (5)? |
|
Definition
-substrate delivery
-waste disposal
-endocrine signaling
-immune response
-thermoregulation |
|
|
Term
| What is the basic relationship between heart weight and body weight? |
|
Definition
|
|
Term
| What is the basic relationship between blood volume and body weight? |
|
Definition
|
|
Term
| Is BW directly or indirectly proportional to HR? |
|
Definition
|
|
Term
| Identify the 2 pumps that comprise the heart and name the circulations they supply. |
|
Definition
-Right: pulmonary arteries to pulmonary
-Left: aortic artery to systemic |
|
|
Term
| Contrast the amount of pressure present in the systemic circulation vs pulmonary circulation. How does this affect cardiac walls? |
|
Definition
-pulmonary circulation has lower pressure, thus right side of heart has thinner wall
-systemic circulation has higher pressure thus the left side has thicker wall |
|
|
Term
| Outline the route that blood takes through the heart (14) |
|
Definition
1. Vena cava: venous return from body
2. Right atrium
3. Tricuspid valve
4. Right ventricle
5. Pulmonary valve
6. Pulmonary artery
7. Lungs (to oxygenate)
8. Pulmonary veins
9. Left Atrium
10. Mitral valve
11. Left ventricle
12. Aortic valve
13. Aorta
14. Body |
|
|
Term
Which muscle types (skeletal, cardiac, smooth) fit into each of the following categories:
a) striated
b) nonstriated
c) voluntary
d) involuntary |
|
Definition
a) Striated: skeletal and cardiac, orderly contractile proteins
b) Nonstriated: smooth, disorderly contractile proteins
c) Voluntary: skeletal
d) Involuntary: cardiac and smooth |
|
|
Term
| What is the location of intercalated disks? Their key components? Function? |
|
Definition
-located in cardiac muscle between myocytes
-desmosomes, cadherins, gap junctions
-allow cardiac myocytes to be electrically and mechanically linked |
|
|
Term
| Definition and Function: Gap junctions |
|
Definition
-connections to form half of an ion channel
-F: ion movement between cells |
|
|
Term
|
Definition
| -cytoskeletal links, linked to desmin in fil |
|
|
Term
Definition: Functional syncytium
-how is this accomplished in cardiac muscle? |
|
Definition
-act line one cell thus contract/relax as a unit
-intercalated disks |
|
|
Term
|
Definition
-3rd most abundant protein in cardiac m, anchored to z line and stretches across to next Z line
-maaaaaassive protein |
|
|
Term
| True or False: In cardiac muscle, actin is the thick filament and myosin is thin. |
|
Definition
| FALSE, actin is thin and myosin is thick |
|
|
Term
| Definition: L-type Ca2+ Handling Protein |
|
Definition
-loc on plasma mem
-voltage-activated
-open a long time
-allows Ca2+ into cytoplasm |
|
|
Term
| Definition: SR Ca2+ Release Channel |
|
Definition
-on SR mem
-releases Ca2+ from SR for contraction (CICR) |
|
|
Term
| Definition: SERCA (SR Ca2+ ATPase) |
|
Definition
-on SR mem
-pumps Ca2+ back into SR |
|
|
Term
| Definition: NXC (Na+-Ca2+ exchanger) |
|
Definition
-on plasma mem
-transports Ca2+ out of cell and Na+ in |
|
|
Term
| Definition: Plasma Mem Ca2+ Pump |
|
Definition
| -transports Ca2+ out of cell, USES ATP |
|
|
Term
| What are the regulatory proteins of Ca2+ handling in cell? |
|
Definition
-Phospholamban: inh SERCA
-Calsequestrin: Ca2+ binding protein in SR, helps SR hold lots of Ca2+ |
|
|
Term
| How can you reverse the effects of Phospholamban? |
|
Definition
| -rev by phosphorylation by PKA or CaMKII blocks inh, thus faster relaxation |
|
|
Term
| How does the role of Ca2+ in smooth muscle contraction differ from its role in skeletal and cardiac muscle? |
|
Definition
-Ca mainly from outside the cell, not SR
-Ca calmodulin dependent process
-changes in myosin, NOT actin, initiates cross-bride cycling |
|
|
Term
| What are the steps of contraction in smooth muscle? |
|
Definition
| Calmodulin binds 4 Ca=> acti MLCK (myosin light chain kinase)=> the phosphorylates myosin=> can now bind actin |
|
|
Term
| How does muscle relaxation differ in smooth muscle than that in skeletal and cardiac? How is it regulated? |
|
Definition
-myosin light chains dephosphorylated by MLCP
-actin/myosin do not interact
-reg by signaling pathways (NO, prostacyclin, stretching) |
|
|
Term
| Outline the relaxation steps in smooth muscle |
|
Definition
| NO (pdc by endothelial cells)=> diffuse to SMC as gas=> act guanylyl cyclase => pd cGMP=> PKG=> myosin light chain phophatase |
|
|
Term
| Where in the body is smooth muscle found? |
|
Definition
| -wall of hollow organs and tubes (GI tract, SI, LI, bladder, blood vessels) |
|
|
Term
|
Definition
| -contracts in bursts to propel contents (uterus, GI tract) |
|
|
Term
|
Definition
| -partially contracted at all times for maintaining pressure (vasculature) |
|
|
Term
| Definition: Single-unit smooth muscle |
|
Definition
| -contracts as a single unit with gap junctions (most, vascular) |
|
|
Term
| Definition: Multi-unit smooth muscle |
|
Definition
| -contains different units that must be neutrally stim to contract (large airways, eye muscles) |
|
|
Term
|
Definition
| -contraction initiated by nerves, multiunit |
|
|
Term
|
Definition
| -contraction not initiated by nerves |
|
|
Term
| Know which initiates action potentials in the heart: cardiac cells or nerves |
|
Definition
-ALWAYS cardiac cells
-pacemaker cells spont gen AP |
|
|
Term
| Know the normal sequence of depolarization in the heart |
|
Definition
0= depolarization
1= partial/rapid depolarization
2= plateau
3= repolarization
4= resting mem potential |
|
|
Term
| Outline the sequence of depolarization of SA node/AV node |
|
Definition
4: pacemaker current, dec K+ current
0: L-type Ca channels open
1,2: not present
3: Ca channels close, K channels open |
|
|
Term
| Outline the sequence of depolarization of Atria/Ventricles/Purkinje Fibers |
|
Definition
4: no major currents active
0: fast Na channels open
1: fast Na channels close
2: L-type Ca channels open (slower but responsible for plateau)
3: L-type Ca channels close, K channels open |
|
|
Term
| What are the major ion currents of the heart? |
|
Definition
-Na+ low inside cells, so rushes in, and depolarizes (towards +72): voltage-gated
-K+ high inside, so goes out, and repolarizes (towards -88) voltage-gated
-Ca2+ low inside cells, so rushed in, and depolarizes (towards +123) voltage-gated |
|
|
Term
| How does the ionic basis of the action potential in pacemaker cells of the SA and AV nodes differs from that in atrial and ventricular muscle cells? |
|
Definition
|
|
Term
| What determines which cell will be the one to generate the action potential for the entire heart? |
|
Definition
| -whichever one depolarizes first |
|
|
Term
| Definition: Effective Refractory Period |
|
Definition
| -cell is depolarized, Na (closed) and Ca (open) channels cannot be reactivated |
|
|
Term
| Definition: Relative Refractory Period |
|
Definition
| -cell is repolarize, some Na and Ca can be activated |
|
|
Term
| Describe the effect of sympathetic NS influence on the rate of pacemaker cell depolarization, AV node conduction velocity, AV node refractory period, and HR |
|
Definition
-sympathetic NS releases NE to act B1 adrenergic
-inc rate of depolarization
-inc conduction speed
-dec refractory period
-inc HR |
|
|
Term
| Describe how sympathetic NS influences rate of pacemaker cell depolarization, AV node conduction velocity, AV node refractory period, and HR |
|
Definition
-via Vagus n (branches R=SA and L=AV)
-dec rate of depolarization
-dec conduction speed
-inc refractory period
-dec HR |
|
|
Term
| Why is the AV node referred to as a "secondary pacemaker" in the heart? Why does it not normally initiate depolarization of the heart? |
|
Definition
-does not normally initiate depolarization of the heart
-SA depolarizes more uickly |
|
|
Term
| Explain why conduction in the ventricular conduction pathways must be fast for proper cardiac function. |
|
Definition
| -want ventricles to contract in a unit so all cells must receive signal at the same time |
|
|
Term
| Definition and Equation: Stroke Volume |
|
Definition
-V of blood ejected by the ventricle with each beat
EDV-ESV |
|
|
Term
| Definition and Equation: Ejection fraction |
|
Definition
-% of blood ejected with each beat
SV/EDV x 100= % |
|
|
Term
| What are the two types of heart valves? Which valves fit into each category? |
|
Definition
-Atrial-ventricular: Right AV (tricuspid) and Left AV (mitral)
-Semilunar (b/n venricles and vessels): no valves between veins and atria |
|
|
Term
| Definition: Cardiac Cycle |
|
Definition
| -electric and mechanical events that repeat with each heartbeat (60/HR) |
|
|
Term
| Describe the mechanism by which valves open and close. |
|
Definition
| -open in one direction when P above> P below (atrial=close when P below>P above (atrial>ventricles and arteries> ventricles) |
|
|
Term
| What are the 4 phases of the cardiac cycle? What occurs in each? |
|
Definition
1. Inflow: when ventricle relaxes= P dec until lower than Left atrium thus opens=> blood goes to atrium so BV (rapid inflow), then atrium contracts (atrial kick) to kick a little more blood into ventricle
2. Isovolumetric contraction: ventricle contracts but cannot go anywhere, so P inc, constant V
3. Ejection: Ventricular P> Aortic P, thus ejected into aorta, aortic valve closes once P reverses again
4. Isovolumetric relaxation: all valves shut, opens once P lower than aortic P |
|
|
Term
| Definition: End-systolic Volume |
|
Definition
| -V of blood in ventricle at the end of Phase 3/ejection (min V) |
|
|
Term
| Definition: End-diastolic Volume |
|
Definition
| -V of blood in ventricle at the end of Phase I/Inflow (max V) |
|
|
Term
| What events of the cardiac cycle correspond to the S1 and S2 heart sounds? Bonus: third and fourth? |
|
Definition
-S1: first, closure of mitral and tricuspin valves (AV)
-S2: second, closure of aortic and pulmonary valves
-Third: near end of ventricular filling, caused by inc tension in chordae tendinae
-Fourth: associated with atrial contraction |
|
|
Term
|
Definition
| -workload put on the heart BEFORE contraction starts |
|
|
Term
| Describe the relationship between fiber length, EDV, and preload |
|
Definition
-fiber length prop to EDC (determined by venous return)
-EDV inc= inc Preload as evident in Frank-Starling Curve |
|
|
Term
| How do increases in preload and afterload affect stroke volume? |
|
Definition
-inc preload= inc F of Contraction= inc SV (up to a point)
-inc afterload= dec SV |
|
|
Term
| Definition: Contractility |
|
Definition
| -strength of the heart's contractile perfomance |
|
|
Term
| How does increased contractility affect stroke volume? |
|
Definition
| -inc contractility= inc peak tension= inc rate of fiber shortening (due to inc Ca influx)= inc SV by emptying ventricles more quickly |
|
|
Term
| When can systolic murmurs be heard? |
|
Definition
-b/n 1st and 2nd heart sound
-contracting: P of LV high and P of LA is low |
|
|
Term
Definition: Mitral incompetence
-what kind of murmur is this? |
|
Definition
-LV leaks back to LA (congenital, degenerative, infection)=> thus body inc HR to make up for blood flow going backwards=> leads to heart failure
-systolic murmur |
|
|
Term
Definition: Tricuspid incompetence
-what kind of murmur is this? |
|
Definition
-RV to RA=> eventually leads to right heart failure
-systolic murmur |
|
|
Term
Definition: Ventral Septal Defect (congenital)
-what kind of murmur is this? |
|
Definition
-would cause blood to flow from LV to RV
-systolic murmur |
|
|
Term
Definition: Aortic stenosis
-what kind of murmur is this? |
|
Definition
-flow will be forced thru too narrow of an opening LV to Aorta
-systolic murmur |
|
|
Term
Definition: Pulmonic stenosis
-what kind of murmur is this? |
|
Definition
-flow will be forced thru too narrow of an opening from RV to Pulmonary a
-systolic murmurs |
|
|
Term
Definition: Patent ductus arteriosus
-what kind of murmur is this? |
|
Definition
-blood from aorta to pulmonary artery (supposed to go away at birth)
-constant murmur |
|
|
Term
Definition: Mitral stenosis
-what kind of murmur is this? |
|
Definition
-blood flow from LA to LV
-diastolic murmur |
|
|
Term
Definition: Tricuspid stenosis
-what kind of murmur is this? |
|
Definition
-blood flow from RA to RV
-diastolic murmur |
|
|
Term
Definition: Aortic insufficiency
-what kind of murmur is this? |
|
Definition
-blood flow from aorta to LV
-diastolic murmur |
|
|
Term
Definition: Pulmonic insufficiency
-what kind of murmur is this? |
|
Definition
-blood flow from Pulmonary a to RV
-diastolic murmur |
|
|
Term
| Definition: Valve incompetence |
|
Definition
| -valve does not close properly, blood leaks through (aka insufficiency and regurgitation) |
|
|
Term
| Definition: Valve stenosis |
|
Definition
| -valve is narrowed thus needs more F |
|
|
Term
Definition: Arborization
-how does this affect diameter and number of vessels |
|
Definition
-branching of the CV vasculature
-diameter dec and number of vessels inc at each branch |
|
|
Term
| Describe the main function of arteries, veins, and capillaries |
|
Definition
-A: distribution of blood from the heart to capillary beds
-C: gas exchange system
-V: collection and return system |
|
|
Term
| How does the total number of vessels of each type and the total area of vessels of each type changes at different levels of arborization (exact number not important). |
|
Definition
-Arteries: as they branch into smaller and smaller vessels, individual vessel A dec, but total A inc
-V: as veins branch, individual A inc and total A dec |
|
|
Term
| Which type of vessels possess the greatest total cross-sectional area? |
|
Definition
| capillaries> veins and arteries |
|
|
Term
| In which type of vessels have the lowest flow velocity? Why is this functionally significant? |
|
Definition
-capillaries
-needs to be slow for proper diffusion of O2 |
|
|
Term
| Describe the basic structural differences b/n arteries, capillaries, and veins |
|
Definition
-A: 3 layers (intima, media, adventitia)
-C: no smooth muscle cells, very little CT
-V: mostly indistinguishable layers |
|
|
Term
| Name and describe the contents of the 3 layers of the arterial wall |
|
Definition
1)Tunica Intima: innermost on lumen; EC, some SMC, some elastic fibers
2)Tunic Media: middle with lots of CT, some SMC. and elastic fibers
3)Tunica Adventitia: outermost; CT mainly colagen |
|
|
Term
| What are the two major cell types that make up the vascular wall in vessels larger than capillaries? |
|
Definition
-vascular endothelial cells
-vascular smooth muscle cells |
|
|
Term
| What cell type forms the capillary wall? |
|
Definition
| -endothelial simple squamous |
|
|
Term
| Give a few examples of the key functions of endothelium (5) |
|
Definition
-interface for gas exchange
-release vasoactive cpds (NO, prostaglandincs, endothelium, etc)=> influence blood flow
-produce and respond to growth factors (VEGF)=> cause new vessel growth (angiogenesis)
-interact with circulating BC's in inflammation
0regulates blood clotting |
|
|
Term
|
Definition
| -veins that are found in between the muscles, as muscles contract, squishes vein, thus making blood move back to heart |
|
|
Term
| Defintion: Respiratory Pump |
|
Definition
| -as you breath in, P drops, thus more blood flows from peripheral to central (following P gradient) |
|
|
Term
Definition and Equation: Fractional shortening
-what is the normal range? |
|
Definition
-the reduction in the D of the L. ventricle that occurs during contraction
(LVD diastole- LVD systole)/ LVD diastole x 100
-normally: 30-45% |
|
|
Term
|
Definition
|
|
Term
| What are the two negative electrodes in the augmented limb leads used for? |
|
Definition
| -their recordings are summed to produce an imaginary reference potential halfway b/n the electrodes (the theoretical center of the heart) |
|
|
Term
| Why do we use 6 different leads? |
|
Definition
| -to look at the heart from different angles |
|
|
Term
| What do each of the parts of a normal ECG trace represent? |
|
Definition
-P wave: atrial depolarization
-QRS cplx: ventricular depolarization
-T wave: ventricular repolarization |
|
|
Term
| Why are the electrical activity of the SA and AV nodes is not shown directly on ECG traces? |
|
Definition
-depolarization not seen b/c too small to be seen when measured at the surface of the bodies
-atrial repolarization is obscured by QRS cplx |
|
|
Term
| How do you determine HR from an ECG trace? |
|
Definition
-mark off 6 seconds, count QRS cplxs, and multiple by 10
=>may sometimes need to count P waves along with/instead of QRS |
|
|
Term
| Definition (short answer): Normal Sinus rhythm |
|
Definition
| -each QRS cplx is preceded by a P wave |
|
|
Term
| Definition (short answer): Bradycardia |
|
Definition
-dec SA node activity= AV node slowly takes over
-rhythm is slower than reference frame in which there is not a P wave before every QRS cplx |
|
|
Term
| Definition (short answer): Tachycardia |
|
Definition
| -heart rate is faster than reference frame |
|
|
Term
| Definition (short answer): Atrial Fibrillation |
|
Definition
| -uncoordinated electrical activity in atria, almost random |
|
|
Term
| Definition (short answer): Atrial Flutter |
|
Definition
| -impulses are being made too quickly, constant P waves, no distinct P waves |
|
|
Term
| Definition (short answer): Ventricular Ectopic Pacemaker Activity (PVCs) |
|
Definition
-Above ventricles (atria, AV node, Bundle of His: QRS will be normal in shape=> supraventricular tachycardia, QRS cplxs abnormally fast and not proceeded by P waves
-in ventricles or ventricular conducting system: QRS will be bizarre in shape=> palpitation, 3 or more PVCs in a row: ventricular tachycardia |
|
|
Term
| Definition (short answer): AV Block |
|
Definition
-1st degree: conduction throughout the AV node is delayed
-2nd degree: only some SA node APs are conducted through the AV node
-3rd degree: none of the SA node APs are conducted through the AV node |
|
|
Term
| True or False: In 2nd and 3rd degree AV Blocks, P waves and QRS cplxs are completely coordinated. |
|
Definition
| FALSE, not coordinated at all |
|
|
Term
| What are a few possible sources of artifacts in ECG recordings? |
|
Definition
-movement of animal during recording
-panting
-limb movement
-coughing |
|
|
Term
| What is meant by "left axis deviation"? Right? |
|
Definition
-left side of heart is enlarged
-right side of heart is enlarged |
|
|
Term
| Which leads do we use to calculated mean electrical axis of the heart? |
|
Definition
|
|
Term
| How do we calculate mean electrical axis of the heart? |
|
Definition
1) measure ht of R wave [up=pos/down=neg]
2)plot on circle of axis [arbitrary units]
3) mark on the tick mark on the corresponding axis for each lead
4) draw straight line from each lead mark
5) draw line from center through the point at which lead lines cross
6) this point is the mean electrical axis |
|
|
Term
| How is the Mean Electrical Axis of the heart clinically significant? |
|
Definition
| -the calculated axis shifts because the affected side of the heart is larger, thus the electrical signal is stronger |
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
| What are the main effector mechanisms for controlling Mean Arterial Pressure |
|
Definition
-vascular radius
-CO
-salt/H2O balance |
|
|
Term
| Where are baroreceptors located? What do they DIRECTLY sense? |
|
Definition
-specialized nerve endings in carotid sinus and aortic arch
-sense wall STRETCH, not P directly |
|
|
Term
Describe the effects of inc/dec MAO on the following:
a) baroreceptor nerve firing rate
b) sympathetic and parasympathetic nervous system activity
c) cardiac output and blood vessel diameter |
|
Definition
-Inc MAP: inc firing of baroreceptors, dec symp tone, inc parasymp tone=> vasodilation: dec HR, lower MAP
-Dec MAP: dec firing of baroreceptors, inc cymp tone, dec parasymp tone=> vasoconstriction: inc HR, raises MAP |
|
|
Term
| Why is the baroreceptor reflex considered a short-term regulatory mechanism and not a long-term one? Ex: sustained hypertension |
|
Definition
| -it will adjust to long-term changes, regarding it as the new normal, thus will not work well for long-term changes |
|
|
Term
| Describe the role that the baroreceptor reflex plays in adjustment of MAP with changes in body position. What occurs without this mechanism? |
|
Definition
-when going from laying down to standing up, blood would want to pool in the feet, but with baroreflex, BP regulates to keep same BP
-without this, BP will drastically drop, called Orthostatic intolerance |
|
|
