cardio Flashcards
Left and right atria
Chambers that receive blood returning from your body through your veins
Left and right ventricles
Chambers where blood is pumped to your body through your arteries
Mitral valve
The mitral valve controls the flow of oxygen-rich blood from the left atrium to the left ventricle
Tricuspid valve
The tricuspid valve controls the flow of oxygen-poor blood from the right atrium to the right ventricle
Aortic valve
The aortic valve controls flow of oxygen-rich blood from the left ventricle to the body
Pulmonary valve
The pulmonary valve controls flow of oxygen-poor blood from the right ventricle to the lungs
heart wall
- pericardium - outer layer of the heart.
- parietal layer and visceral layer with space between
- Myocardium - muscle layer in middle
- endocardium - inner lining
heart chambers
- right atrium - collects oxygen poor blood returning from your body
- left atrium - chamber that collects oxygen rich blood returning from the lungs
- right ventricle - pumps oxygen poor blood through pulmonary valve and into lungs
- left ventricle - largest and strongest chamber of the heart. pumps o2 rich blood through aortic valve. extra myocardium muscle
heart valves
- atrioventricular valves:
1. tricuspid valve: The tricuspid valve controls the flow of oxygen-poor blood from the right atrium to the right ventricle
2. mitral valve: The mitral valve controls the flow of oxygen-rich blood from the left atrium to the left ventricle - semilunar valves:
1. pulmonic semiulnar valve: The pulmonary valve controls flow of oxygen-poor blood from the right ventricle to the lungs
2. aortic semiulnar valve: The aortic valve controls flow of oxygen-rich blood from the left ventricle to the body
heart vessels
- Superior/Inferior Vena Cava (SVC, IVC) = into rt atrium
- Pulmonary Trunk to Pulmonary Arteries = out rt vent to lungs
- Only deoxy arteries in body
- Pulmonary Veins = into lt atrium
- Only oxy veins in body
- Aorta = out lt vent to all tissues of body
SinoAtrial Node
- pacemaker of the body
- starts the first contraction of the heart
- keeps HR consistent and constant
AtriVentricular Node
- sends impulse through ventricles to contract
Systole and Distole
- Systole = contraction, Diastole = relaxation
- We can say atrial systole occurs during ventricular diastole, and atrial diastole
occurs during ventricular systole - when you just hear “systole” that refers to ventricular systole (ventricles are contracting while the atria are relaxed, atrial diastole)
Pulmonary vs. Systemic circulation
pulmonary - heart and lungs
- recycles blood
- takes up co2 and puts o2 into blood
systemic - heart and rest of body organs and tissues
- distribute o2 to tissues and organs and pick up CO2 and recycle it through pulmonary circulation
- brain picked up 02 from systemic blood and giving back co2
- blood travels through vena cava - to right atrium - through tricuspid valve - to rt ventricle - to semilunar valve - pulmonary after - lungs - gas exchange vis diffusion co2 into lungs and o2 into blood - blood leaves lungs with o2 - pulmonary vein - to lt atrium - bicuspid valve - lt ventricle - semilunar valve - aorta - to body tissues and organs - tissues pick up 02, give back co2
cardiac circulation
heart’s blood supply
- myocardium - left main corononary (left descending and circumflex) and right main coronary after
- intramyocardial arteries
- perfusion to myocardium
- changes in aortic pressure and compression of myocardial vessles during systole
- during heart contractions it affects coronary blood supply
- during systole - pressure on myocardial vessels and reduces myocardial blood flow
- during stress cardiac arteries dilate. ischemia happens when these arteries cannot dilate
- cardiac veins drain into cardiac sinus = collects deoxy blood from coronary heart circulation and sends back to rt atrium to get o2
Coronary arteries
§ Come off the aorta (=fresh O2!) either on the LEFT or RIGHT side of the Pulm. Trunk
§ Left Coronary Artery; branches into:
• Left Anterior Descending (LAD) or Anterior interventricular
o “Widow maker” because its blockage leads to sudden and deadly MI (heart attack)
• Circumflex Artery
§ Right Coronary Artery; branches into:
• Right Marginal
• Posterior Descending (PDA) or Posterior interventricular
conduction system
SA node - wall of atrium - AV node - atria contracts - atrioventricular bundle - right and left bundle branches - action potential goes to apex - ventricular walls - perking fibers - contraction in unison
- SA node
- AV node
- Bundle of His
- Right and left bundle branches
- Perkinje fibers
EKG
Know how to draw and label!
o Measures ELECTRICITY of heart (not heartbeat!) o Pwave
- Atrial Depo o QRS Complex
- Vent. Depo and Atrial Repo (Atr. repo is hidden by big vent. depo) o Twave Vent. Repo
o Flat segment between P-Q = Atr. contraction o Flat segment between S-T = Vent. contraction
- rt atrium signal from SA node (pacemaker)
- signal spreads across both atria and tell muscle cells to depolarize and contract = atrial systole = p wave
- period of conduction between atrial systole and ventricle contraction = PR segment = AV node releases signal to ventricles
- enters bundle of his and spreads through bundle branches and perkinge fibers along ventricle walls = ventricle systole = contraction of ventricles = QRS = rapid ventricle depolarization
- signal passes out of ventricles, vertical walls relax and recover = ventricle diastole = ST period = ventricle depolarization
- T wave = ventricle depolarization
- QT period = depolarization and depolarization of ventricles
heart sounds
Heart sounds (“lub/dub”) = sounds made of the valves closing
o S1 –“lub”
- AV’s closing = vents. start to contract
o S2–“dub”
- Semi’s closing = vents. relax
Cardiac Innervation from Brain
o Sympathetic nerves - increase heart rate (norepi/epi) - increase blood pressure o Parasympathetic nerves (Vagus nerve) - decrease heart rate (AcH)
Arteries
o Greatest velocity of blood
o Highest pressure
Arterioles
o Greatest resistance (due to push of narrower vessel walls on blood flow)
o Resistance leads to many pathos!
Capillaries
o Lowest resistance
o allows for fluid/gas/nutrient exchange with tissues
Venules
o drain out of caps
Veins
o Lowest pressure
Vessel Anatomy
o Lumen = open center of the tube o Tunica intima = endothelium
- smooth epithelial lining for good blood flow
- need to keep intact or PATHOs!
- veins have added valves made from this endothelium
• =prevents backflow and ensure 1-way flow back to heart
• aided with skeletal muscle contractions and respiration to move
deoxy blood back to heart
o Tunica media
- smooth muscle = vasoconstriction and vasodilation!
- arteries have thicker muscle and have added elastic layers due to high
pressure!
o Tunica externa = adventitia
- outer connective tissue of vessel
Blood Pressure (BP)
o = force of blood on vessel walls
o Resistance = blood vessel walls’ push back on blood
Measurement BP
o BP = CO x PR (cardiac output times peripheral resistance)
- CO = HR x SV (heart rate times stroke volume)
- Cardiac Output is the amount of blood pumped out of the heart per
minute – we multiply the heart rate (beats/min) times the stroke
volume (amt of blood pumped per beat (mL/beat))
- You will not have to actually calculate any of these
o Cardiac output is affected by the preload and afterload
- Preload – how much did ventricle fill = STRECTH
- Afterload – pressure needed to eject this blood out of heart
• Myocardial contractility = the heart muscles’ ability to contract
• more contractility = more force of contraction = increase BP
Control of BP
o nervous system measure with baro’s (pressure) and chemo’s (CO2) to modify
cardiac function and BP
o vasodilation/vasoconstriction of vessels