The ____ is the top of the heart and the _____ is the bottom of the heart
What are the 2 layers of the pericardium and where are they located?
- 1. parietal (outer layer)
- 2. visceral (inner layer-closest to the heart)
What secretes pericardial fluid into the pericardial cavity?
What is the auricle?
It is a pouch-liek structure that increases the volume capacity of the atria
True or false, chordae tendonae connect papillary muscles to the pulmonary and aortic valves.
False, only the mitral(bicuspid) and tricuspid valves have chordae tendonae
Which valves are on the right side of the heart?
Tricuspid and pulmonary valves
The superior and inferior vena cava feed ______ blood into the ______ _______.
What 3 arteries branch off the aorta?
- 1. Brachiocephalic trunk
- 2. Left common carotid
- 3. Left subclavian artery
What is the function of the pulmonary arteries?
They exchange CO2 with O2
What is the order of conduction through the heart?
- 1. SA node
- 2. AV ndoe
- 3. Bundle of His
- 4. Right & left bundle branches
- 5. Purkinje fibers
What layer of the heart lines the entire cardiovascular system?
What is the funciton of the pulmonary veins?
They bring oxygenated blood from the lungs into the left atrium
____ is when the heart is contracting and ____ is when the heart is relaxing
Which 3 phases of the cardiac cycle are considred systole?
- 1. Atrial contraction
- 2. isovolumetric contraction
- 3. Ventricular ejection
What is going on during isovolumetric contraction?
No blood is leaving the ventricle and the AV valves are closed, and the semi-lunar valves begin to open
Cardiac output is defined as?
The amount of blood pumped out of the left ventricle per minute
CO= HR x SV
What is EDV?
The volume of blood left in the ventricle at teh end of diastole
What is venous return?
The amount of blood returned to the right atrium
What determines pre-load?
EDV, if you increase EDV you increase SV
What is the Frank-starling mechanism?
When the sarcomeres reach optimal length leading to greater strength of contraction
What are chronotropic effects?
Any effects that change the heart rate (Ex: positive chronotropes increase HR)
___ wave is atrial depolariation
The QRS complex is _______ deplarization
____ wave is ventricular repolarization
S1 sound is the?
Closing of the AV valves
_____ sound is the closing of the semi-lunar valves
What do the S3 and S4 sounds signify?
- S3- ventricular filling
- S4- abnormality in atrial contraction
Why is AV node transmission delayed?
to allow for atrial contraction before the ventricles contract
due to fewer gap junctions
What is the resting membrane potential for the SA node?
_____ decreases HR by releasing ____ from the Vagus nerve, increasing _____ permeability causing ____polarization
_____ increases HR by releasing ____ which increases ___ and ___ permeability causing ____polarization
- NE (norepinephrine)
Where does calcium come from for use in cardiac muscle contraction? (2)
- 1. Sarcoplasmic recticulum
- 2. extracellular fluid
What is the time frame for a normal P-wave?
What is the time frame for a normal Q-P or P-R interval?
A wave of depolarization moving toward a positive electrode you get a ______ deflection on an EKG
A wave of depolarization moving away from a positive electrode you get a _______ deflection on an EKG
What are the 3 bipolar leads, their charges, and locations?
- Lead I - R arm (-), L arm (+)
- Lead II- R arm (-), L leg (+)
- Lead III- L arm (-), L leg (+)
What are the 3 unipolar leads, their charges, and locations?
- AVF- L foot (+), both arms (-)
- AVL- L arm (+), R arm & L foot (-)
- AVR- R arm (+), L arm & L foot (-)
Which 2 chest leads are the most positive? Why?
V5 and V6 because depolarization is moving directly toward those electrodes
Bradycardia is _____bpm and tachycardia ______bpm
What signifies a premature atrial contraction (PAC) on an EKG?
abnormal P-wave, earlier than expected
A tall/deep QRS complex signifies what on an EKG?
Premature ventricular contraction (PVC) because there is NO opposition of depolarization
Flutter is caused by ____ ectopic foci and has rythms at ____bpm
Fibrillation is caused by _____ ectopic foci and has rythms at ___ bpm
Identical P-waves in rapid succcession signifies _______ ________
A prolonged P-R interval (>0.2) signifies?
AV block, there is a delay in transmission
A widened QRS (>0.12) with "rabbit ears" signifies?
Bundle branch block
What is happening if the QRS is negative in Lead I and AVF?
There is extreme right axis deviation (RAD)
If QRS is ____ in Lead I and __ in AVF there is right axis deviation
If QRS is _____ in Lead I and ___ in AVF there is left axis deviation
RAD= (-)Lead I, (+) AVF
LAD= (+)Lead I, (-) AVF
Hypertrophy shifts the axis to the ______ side.
RV hypertrophy causes ___ HTN
LV hypertrophy causes ___ HTN
If there is an amplified QRS complex (>35mm in V1 and V5) what is wrong?
Left ventricular hypertrophy
Myocardial infarction shifts the axis ______ from the side of infacrtion
What are the 3 signs of myocardial infarction?
- 1. inverted T-wave (opposite repolarization)
- 2. elevated/depressed S-T segments (not at baseline)
- 3. significant Q-wave (>1 box) *don't look in AVR-there will always be a Q-wave
What is the function of the capillaries?
They are the site for fluid and gas exhcange
What is the thickest tunic around the arteries? (It has smooth muscle and is innervated by the SNS)
_____ are more compliant than _____ because they hold more blood and act as a reservoir.
What is the purpose of having muscular arteries?
They allow for greater vasocontriction/dilation
True or false, veins do not have valves to prevent the backflow of blood
False, veins DO have valves to prevent backflow
True or false, low compliance increases pressure
A decrease in vessel diameter ______ TPR, thus _________ compliance
What is total peripheral resistance (TPR)?
The resistance of blood flow through the vasculature
The respiratory pump ______ venous return due to the pressure gradients during inspiration
Activation of RAAS _____ blood pressure
How does angiotensin II cause the kidneys to retain salt and water? (2 ways)
- 1. direct- stimulates kidneys to retain salt and water
- 2. indirect- stimulates adrenal gland to secrete aldosterone
ADH (vasopressin) ______ blood pressure and is released from the ______ _______ ______
posterior pituitary gland
Under what 2 circumstances is ADH released?
- 1. decreased BV (causing vasoconstriction)
- 2. increased osmolarity (cause kidneys to retain salt and water)
ANP (atrial natriuric peptide) ______ blood pressure and is released by cells of the _____ inresponse to stretch
Under what 2 circumstances is ANP released?
- 1. increased BV (causing vasodilation)
- 2. decreased osmolarity (causing the kidneys to loose salt and water)
True or false, there is SNS innervation in the capillaries, precapillary sphincters, and metarterioles.
False, NO SNS innervation in those areas
What are baroreceptors and where are they located?
They are stretch receptors useful regulate rapid BP changes
Located in the walls of large arteries (carotid, aortic arch)
What are chemoreceptors and where are they located?
They are receptors that sense the CO2, O2, and pH levels
Located in the carotid and aortic bodies
The barorecptors function in ___-___mm Hg and the chemoreceptors function in _____ mm Hg
What is the vasodilator theory?
Decreased O2 causes the release of vasodilators which act on precapillary sphicters, metarterioles, and arterioles dilating them
What is the most important vasodilator substance?
When is NO released? Where is it released from?
Released in response to shearing stress of increased blood flow in the arteries
Released from endothelial cells
_______ is a vasoconstrictor released from damaged vessels
Bradykinin and histamine cause _______ and ______ capillary permeability
Ischemia causes tissues to release _____ and ____ stimulating angiogenesis
What are the 4 starling forces?
- 1. capillary hydrostatic pressure (BHP)
- 2. interstitial fluid colloid osmostic pressure (IFOP)
- 3. intersitial fluid hydrostatic pressure (IFHP)
- 4. capillary colloid osmotic pressure (BCOP)
Which starling force is normally zero?
intersitial fluid hydrostatic pressure (IFHP)
_____ side favors net filtration and _____ side favors net reabsorption
Which 2 starling forces cause fluid to leave the capillary?
capillary hyrdrostatic pressure (BHP)
interstitial fluid colloid osmotic pressure (IFOP)
What is the lymphatic pump?
Contraction of muscles surrounding the lymph, they increase lymph flow
Net filtration pressure=____?
- (BHP + IFOP) - (BCOP + IFHP)
- (Forces out) - (Forces in)
What is atherosclerosis?
Thickening of an artery wall as a result of a build-up of fatty materials like cholesterol
What are 3 main causes of atherosclerosis?
- 1. Shear stress
- 2. Hypertension
- 3. Smoking
True or false, LDL supresses TGF-gamma which normally protects vessels from injury
False, LDL supresses TGF-beta which protects the vessels
Hypercholestereolemia and smoking leads to _________ LDLox
In what 3 ways does atherosclerosis alter blood flow?
- 1. narrowing of the artery due to ischemia
- 2. plaque rupture leading to clot formation
- 3. aneurysm leading to ballooning and rupture
In what 4 ways does hyperglycemia lead to atherosclerosis?
- 1. increase in vascular smooth muscle proliferation
- 2. increase in magrophage engulfment of oxLDL leadign to fatty streak formation
- 3. decreases NO production which decreases vasodilation and compliance
- 4. increases production of AGEs
How does the production of AGEs in hyperglycemia lead to atherosclerosis? (4)
- The excess glucose will attach itself to other proteins altering their structure and function causing:
- 1. cross-linking of proteins trapping oxLDL
- 2. alters ECM decreasing compliance
- 3. generating ROSs
- 4.binding to AGEs stimulating inflammatory response
Hypertension is defined as BP _____?
Greater than or equal to 140/90
Which type of HTN is caused by NSAIDs, caffeine, ephedrine, and excessive salt intake?
What are the 4 factors contributing to primary HTN?
- 1. overstimulation of SNS
- 2. Increased BV (due to kidneys restting equilibrium)
- 3. Increased RAAS activation
- 4. Increased release of vasoconstrictors
What are the 5 causes of heart failure?
- 1. dysfuntion of coronary arteries
- 2. HTN
- 3. cardiomyopathy
- 4. heart valve disorder
- 5. abnormal HR
What is heart failure?
When the heart fails to pump an adequate blood supply to satisfy needs (decreased CO)
True or false, norepinephrine is toxic to myocardial cells.
True, it can cause necrosis or apoptosis
How does activation of RAAS exacerbate heart failure?
- It increases the workload of the heart
- Angiotensin II will stimulate ventricular remodeling
- Aldosterone leads to water retention causing volume overload
What is the most common cause of death in heart failure? Why?
Pulmonary edema because it causes deoxygenation of the blood
What are they main causes of death for patients with HTN? (4)
- 1. strokes
- 2. coronary heart disease
- 3. heart failure
- 4. renal failure
Why does ventricular remodeling contribute to heart failure?
It changes the size, shape, and function of the heart leading to a decline in systolic or diastolic function
What stimulates ventricular remodeling in heart failure? (3)
- 1. myocyte loss
- 2. hypertrophy
- 3. fibrosis in ECM
Why are beta-blockers beneficial in treating heart failure?
They inhibit the SNS reducing the workload of the heart
Why are ACE inhibitors, ARBs, aldosterone antagonists, and diuretics beneficial in treating heart failure?
ACEs, ARBs, and aldosterone antagonists inhibit RAAS activation to decrease salt and water retention
Diuretics decrease the salt and water intake
What is pericarditis?
Inflammation of the pericardium caused by fluid accumulation in between the visceral and parietal pericardium
True or false, pericarditis can be caused by pharmacologic therapies.
True, hydralazine, dilantin, and penicillin can cause pericarditis
It can also be caused by infections
How does pericarditis decrease MAP?
It prevents ventricle filling causing a decrease in EDV, SV, CO, decreasing MAP
What are the symptoms of pericarditis?
Referred pain on the left side of the chest, neck, and shoulder
How is pericarditis treated?
Acute- NSAIDs and corticosteroids
Pericardiocenteis (draining fluid)
Pericardiectomy (removal of pericardium)
What is hypertropic cardiomyopathy?
A disease of the myocardium where there is thickening(hypertrophy) of the walls of the heart
True or false, hypertrophic cardiomyopathy is a genetic disorder.
Besides sudden death, what other symptoms are associated with hypertropic cardiomyopathy?
Breathlessness, angina, arrhythmias, or fainting
Why is alcohol septal ablation effective in treating hypertrophic cardiomyopathy?
The injection of the alcohol will thin tissue
Why are calcium channel cblockers effective in treating hypertrophic cardiomyopathy?
The decrease the contractility of the heart and slow the heart rate, reducing the workload
What is the most effective treatment for hypertrophiccardiomyopathy?
Implanting a defibrillator
What is mitral valve prolapse?
When the mitral valve bulge bacck into the left atrium preventing a tight seal
True or false, in secondary mitral valve prolapse the cusps are oversized or too thick
False, the cusps are thickend in primary mitral valve prolapse
What 4 diseases are linked to mitral valve prolapse?
- 1. marfan's syndrome
- 2. osteogenesis imperfecta
- 3. myxomatous degeneration
- 4. ischemic heart disease
What are 4 methods for diagnosing mitral valve prolapse?
- 1. listening to the heart (midsystolic click)
- 2. echocardiography
- 3. transesophageal echocardiogram
- 4. EKG (inverted T-waves)
Why are anticoagulants used for treatment in mitral valve prolapse?
It prevents the leftover blood from coagulating
What is hypovolemic shock?
Shock due to a decrease in blood vilume due to burns. dehydration, or excessive blood loss
How does the body compensate for hypovolemic shock?
RAAS activation, SNS activation, baroreceptors, ADH ad NE secretion
What treatments are used in hypovolemic shock? (3)
- 1. electrolyte replenishment
- 2. total blood transfusion
- 3. dopamine (to protect the kidneys)
What stage of hypovolemic shock is marked by total blood volume loss >40%, HR>140, coma?
Symptoms of stage 1 hypovolemic shock are?
Stage 1=total BV loss up to 15%
slight anxiety and pallor skin