Cardiophysiology Flashcards
How many types of tissues are used?
4
Connective tissue (6) types
Blood, cartilage, bone, etc. Everything else.
Nervous Tissue
Neurons and glial cells for communication
Muscle Tissue
Cardiac- contract
Skeletal- move body through joint and space
Smooth-Lining of organs like GI track
Dependent on calcium and sodium.
Epithetial tissue
-Lining of the respiratory and digestive track.
-Epidermis, outside and endodermis inside.
Decide what travels the barrier.
Luminal- facing the light
basolateral- facing inwards.
Heart located within what cavity? What is the anatomical position?
In the thorax cavity.
Look at it facing someone else.
My right will be the left.
Vena Cava
Aorta
Coronary arteries
Vena Cava Biggest vein of the heart that brings deoxygenated blood to the right atrium.
Aorta biggest artery of the heart that carries oxygenated blood out to the body.
Coronary arteries wraps around the heart and feeds it like a crown.
Veins take blood in the heart and artery take blood away.
Where does the right side and left side of the heart pump blood to?
Right side pumps deoxygenated blood to the lungs.
Left side pumps oxygenated blood to the body.
What anchors the valves and what are the two atrial/ventricular valves?
LABRAT
the chordae tendineae anchor the valves and prevents backflow of blood. They are the heartstrings of the heart.
What is the flow of blood?
Always from high to low pressure.
What is ischemia and ischemia stroke?
Ischemia is when parts of the body are deprived of oxygens and nutrients from the blood.
An ischemia stroke is when the brain isn’t being fed.
What is a heart murmur ?
Leakage sound that occurs when the blood flows back to the atrium from the ventricle or from the aorta or pulmonary valves to the ventricles.
What happens when the heart is overworked?
The ventricles get smaller which leads to heart failure.
What are the interventricular septum and papillary muscles?
The interventricular septum is what divides the left and right ventricles.
Papillary muscles are muscles from which the chordae tendinea arise from.
What is the sequence of blood flow?
Deoxygenated blood from the right atrium(though the vena cava) goes through tricuspid valve to the right ventricle then up the pulmonary valve to the pulmonary trunk and pulmonary arteries then to the lung to get oxygenated. Oxygenated blood comes through the pulmonary veins to the left atrium then though the mitral or bicuspid valve to the left ventricle then trough the aortic valve to the aorta and goes to every part of the body.
Autorhythmic cells (SA and AV nodes)
Generate action potentials and control the heartrate though slow depolarization. No need for the nervous system. Never at rest.
-60 is the new resting potential and -40 is the threshold potential.
1)At -60 mV, If (funny) channels open and sodium rushes in and potassium leave the cell. Depolarization occurs.
2)At -40 mV, funny channels closes and Calcium T-channels open because the threshold is reached. Then L-channels open and it’s the action potential rising phase.
3) At the peak, calcium channels closes then slowly potassium channels open which repolarizes the cell.
4) Once at -60 mV, the cycle starts again.
Contractile cells
Electrical signals direct the sequential contraction and moves blood through the heart.
Resting potential at -90 mV.
Sodium goes in first, then potassium and chloride leave. Calcium goes in and potassium keeps leaving which creates a plateau effect. Potassium keeps leaving till resting potential is reached.
Why is the plateau effect necessary
The plateau effect prevents tetany because we don’t want the heart to fully contract.
Systole vs diastole
Systole is when the heart contracts and diastole is the heart at rest.
Where does the electrical conduction occurs
It begins at the SA node and continues through the AV node, bundle of his and through the purkinje fibers.
They activate ventricular contraction.
Tachycardia vs bradycardia
Tachy is fast and brady is slow
The autonomic nervous system ANS controls heart rate
Parasympathetic slows heart rate
Sympathetic raises heart rate
Electrical conduction of the heart is measured by the EKG
P wave for atrial contraction, depolarization
QRS complex for the activation of the ventricles
T wave is the recovery wave after the QRS complex.
The pressure-volume loop is the changing relationship between ventricular volume and fluid pressure.
A-A” is passive ventricular filling, blood in atrium
A’-B is atrial contraction, forces blood down to ventricles
B-C is isovolumetric ventricular contraction, throw blood against valves
C-D is ventricular ejection
D-A is isovolumetric ventricular relaxation
Under parasympathetic( slow heart rate)
The resting potential is lower which causes a slower rate of spontaneous depolarization due to the increase efflux of potassium and slower influx of sodium into the Autorhythmic cells.
Under sympathetic( fast heart rate)
There is a faster rate of spontaneous depolarization due to the increase of calcium and sodium in Autorhythmic cells.
Cardiac output (Q)is the work of the heart
Calculated by stroke volume( EDV-ESV) x the heart rate.
Increased by sympathetic NS and decreased parasympathetic NS
Wiggers diagram describe the relationship between pressure, volume, electrical conduction and blood flow
QRS is the beginning of Ventricular systole
Ventricular pressure goes higher than atrial pressure
Two heart sounds
Sound 1 occurs when the mitral valve closes and the ventricle is contracting
Sound 2 occurs when the aortic valve closes and the blood hits the valve. Dicrotic notch
Risks factors of Heart disease
Smoking
Hypertension
High levels of LDL
Cholesterol
Steroid hormone formed by 4 fused rings that stabilized the membrane. Total cholesterol is LDL+
LDL
Low density Lipoprotein adds cholesterol to plaque.( atherosclerosis) which can lead to hardening of arteries.
HDL
High Density Lipoprotein that removes cholesterol from plaque. We want more of this.
Heart Attack= myocardial infraction
Necrotic tissue formation at a specific part of the heart due to ischemia. the lack of oxygen delivery.
Two types of stroke
Ischemic: Lack of blood flow in the brain, build up of pressure
Hemorrhagic: Broken blood vessel in the brain
Diseases affecting the valves
Stenosis- Valve is stiff and unable to open fully.
Regurgitant- Valve allows backflow of blood from one chamber to the next, think of vomit.
Congestive Heart Failure
Inability of the heart to adequately pump blood throughout the body.
Left side failure leads to backup of fluid into the lungs, rales or crackles in the lung, pink, frothy sputum.
Right side failure:
Backup of fluid into systemic circuit and edema especially in lower extremities.
Atrial fibrilation
Irregular heartbeat due to disorganized electrical signal and the atriums shake.
Arrhythmia
Leads to ventricular tachycardia due to abnormal electrical signals in the ventricles.
Caused by cation imbalance.
Partial Block vs Complete block
A partial block is when the heart rhythm is reduced due to a delay in electrical conduction. Lowers the EKG rhythm from 5 to 3 cycles.
A complete block is the rhythm is reduced to only 2 slow cycles with reoccurring p waves in between.
Calcium and Potassium imbalances can be identified through changes
They both affect the P wave.
Calcium makes the P wave smaller when hypercalcemia and wider when hypocalcemia.
Potassium makes the P wave smaller in length when hypokalemia and bigger when hyperkalemia.
Atherosclerosis, vessel occlusion
hardening of arteries due to plaque buildup that limits blood flow.
LDLs gets trapped into the plaques which hardens and forms blood clots that decreases blood flow and makes the heart work harder.
Stenosis
The narrowing of arteries.
How do babies breathe?
Through a closed pulmonary circuit causes shunting of blood directly from the right heart to the left heart and aorta.
The oxygenated blood from the mother travels through the placenta then the umbilical cord and through the liver and into the vena cava.
Ductus Arteriosus and Foramen Ovale
Ductus Arteriosus allows oxygenated blood to flow directly from the pulmonary trunk to the aorta.
Foramen Ovale allows oxygenated blood to flow directly from the right to the left atrium.
PFO
Failure of the foramen Ovale to close at birth and the deoxygenated blood can go the left atrium and mix with oxygenated blood to other parts of the body.
DVT and embolism
Deep Vein thrombosis is when a blood clot forms.
Thrombus is when the blood clot doesn’t move.
Embolism is when the blood clot travels to different location of the body. Ex: Blood clot from the calf can go up to the lungs and lead to pulmonary embolism.
What happens when PFO and DVT occur together? PFO co-morbidity
A blood clot from a part of the body can travel up to the right atrium and it can directly go the left atrium through the open Foremen Ovale which can lead to a stroke and other issues in the body
What is the difference between veins and arteries?
Veins are larger than arteries, they can carry more blood but they are less muscular. Veins defy gravity and therefore have valves to prevent backflow.
Arteries are very muscular and can expand and contract. They are elastic.
Dicrotic Notch
When the aorta expands to receive blood and then contract which makes the second heart sounds when the blood hits the aortic valve.
Capillaries
Exchange of nutrients and wastes between arteries and veins. Across the capillary membranes.
Fenestrated Capillaries
Windows that allow passage of larger substances like in the kidney.
How is flow of blood calculated?
Q= change in pressure( force of fluid in a container)/ resistance( determined by length, diameter and viscosity).
Portal System 1
Between GI and Liver.
Two sets of capillaries that don’t go to the heart first.
Guts and liver capillaries absorb nutrients and send it to liver and detoxification.
Portal System 2
HPA AXIS produces hormones.
Hypothalamus sends a signal to the pituitary gland then to the endocrine capillaries and the exchange occurs there.
Antidiuretics hormone (vasopressin is a high pressure protein) decreases urine output so waste stays in blood which means increasing blood pressure and blood volume.
Increased Blood Volume=
Increased Blood Pressure
Capillary exchange reflects the balance of oncotic and osmotic forces
capillary hydrostatic pressure= interstitial fluid hydrostatic pressure. It decreases when water leaves the cell.
Capillary osmotic pressure= Interstitial fluid osmotic pressure or colloid osmotic pressure. It doesn’t change because the proteins are non penetrating.
What is the net pressure?
The net pressure equals= hydrostatic pressure- colloid osmotic pressure.
Positive NT indicated filtration and a negative NT indicates absorption.
Arteries vs Veins
Arteries in red do net filtrations (pushes out the plasma) and veins in blue do net absorption( pushes in the plasma).
There are equal at the capillaries.
Respiratory system
CO2 travels as bicarb thru veins with wastes and goes to the lungs. O2 and nutrients gets absorbed via arteries and goes into the cells.
Hb-O2 saturation rages from 98% to 75% during normal breathing
From the lungs ( hemoglobin is completely saturated) then to the tissues, hemoglobin release 25% of oxygen at 40 which is the resting potential.
Fetal hemoglobin
Fetal hemoglobin has a higher affinity than an adult, fetus suck oxygen out of the body.
Bohr Effect
Results from changes in temperature, pH and PCO2 that alters hemoglobin O2 affinity.
Effect of Ph
pH drops when exercising or doing physical activities which signals hemoglobin to let go of some oxygen.
Ph changes the confirmation of molecules.
Effect of temperature
While exercising, the body’s temperature increases which lead to more oxygen being released.
Effect of pressure CO2
As C02 pressure increases, hemoglobin releases more oxygen.
Effect of BPG
BPG is a signal that tells hemoglobin to release more oxygen.
Low blood pressure in venous vessels requires adaptation to maintain blood flow
Veins have a low pressure due to a larger diameter and thinner walls. They have valves and muscle pumps.
Role of the Lymphatic system
The lymphatic system drains interstitial fluid from capillaries and returns to the blood.
Also transport lipids, immune function and maintain blood volume= pressure.
What does impediments to capillary exchange and lymphatic return lead to?
It leads to Kwashiorkor which is a deficit of proteins in children which drains water from capillaries and lead to swelling (edema)
It also leads to Lymphedema which is due to the lymphatic system not draining the excess fluid and therefor leads to extreme edema.
Arterial blood pressure
It reflects diastole and systole by measuring how much pressure is exerted and how hard is the heart working.
Stop arterial blood flow and no sounds can be heard then sounds are created by blood flow. Blood flow is silent when the artery is no longer compressed.
Blood pressure homeostasis
The mean arterial pressure is affect by cardiac output which is measured by stoke volume and heart rate.
What is the mass movement of fluid between the blood and the interstitial fluid and what two pressure gradients determined that
Bulk flow
Determined by hydrostatic or osmotic pressure.
If the direction of bulk flow is into capillary then the movement is
Absorption
If the movement of bulk flow is out of the capillary then the movement is called
Filtration
