Chap. 7 Cardiovascular Flashcards
The Atrium is known as the
Receivers
The Ventricles are know as the
Pumpers
What is systemic blood flow?
Out to the body
What side does blood flow start?
Right side- Pulmonary
The blood flow on the right side of the heart is oxygenated or deoxygentated?
Deoxygenated
The Left Side of the heart is what type of circulation?
Systemic
What happens to the left side of the heart with exercise and fatigue?
Hypertrophies
What muscle fiber is the heart muscle?
Type I
What is the heart muscle called?
Myocardium
What is the myocardium highly composed of?
Capillary density and Mitochondria
What are cardiac fibers connected by?
Intercalated discs
Gap junctions rapidly conduct what?
Action potentials
Desmosomes do what?
Hold cells together
What are the 3 characteristics for Skeletal muscles?
Large, long, multinucleated
What type of contractions are skeletal muscle?
Intermittent, voluntary
What happens with Calcium within skeletal muscle?
It is released from the SR
4 Characteristics with Myocardial cells: (Heart muscle)
Small, short, branches, one nucleus
What type of contractions does heart muscle or myocardial cells have?
Continuous, involuntary rhythmic contractions
What bring blood supply to the heart?
Coronary Arteries, Right to Right & Left to Left
What is the blood flow on the right side of the heart? (Slide 8)
Inferior & Superior Vena Cava, Right Atrium, Right Semilunar (Tricuspid Valve), Right Ventricle, Pulmonary Valve, Pulmonary Artery to LUNGS to oxygenate.
What is the blood flow on the LEFT side of the heart?
From lungs, pulmonary veins, Left Atrium, Mitral valve (Bicuspid Valve), Left ventricle, aortic valve, aorta to body.
What is the cardiac cycle?
All mechanical and electrical events during one heartbeat
What is Diastole?
Relaxation phase- chambers fill with blood- lasts 2x as long at systole
Systole is
Contraction phase
What happens during Ventricular Systole?
Ventricular pressure rises, “Lub”, SLV open, Blood is ejected, ESV
What sound happens when the AV valves close?
Heart sound 1, “Lub”
What are the 4 heart cells that generate electrical signal?
-SA Node
- AV Node
- AV Bundle
- Purkinje Fibers
How is the electrical signal spread?
Via Gap Junctions
What is rate of intrinsic HR?
100 BPM
The pacemaker of the heart?
SA Node
What side does the SA stimulate?
Right Atrium & Left Atrium
What is the job of the AV node?
Regulator, delays to allow ventricles not to close or fill too quickly.
Allows the Right side to contract before the left.
What is the purpose of the AV Bundle?
Relays signal to the RV and LV
What are the 4 parts of the electrical activity of the heart?
- SA node- pacemaker initiates contraction
- AV node is the regulator it allows the right side to contract before the left side.
- AV bundle (bundle of him) travels signal down interventricular septum, divides into right and left bundle toward apex
- Purkinje fibers send signal INSIDE RV and LV, stimulating contraction
What is ejection fraction?
% of blood that is leaving per stroke
What is stroke volume?
How much blood is leaving the heart
What is Diastole?
Fill up, relax
What is Systole?
Push out, contract.
SBP
Systolic Blood Pressure: highest pressure in artery
DBP
Lowest pressure in artery
How much blood to veins contain at rest?
2/3 of blood volume
What area within the vasculature holds the most blood volume?
Veins- 64%
When does “LUB” occur?
Ventricular Systole- or Ventricular Contraction; when the AV valves close at the start. (V pressure rises)
The “Dub” is?
The Aortic and Pulmonary valves closing; pressure drops.
What extrinsic control of heart activity occurs with parasympathetic nervous system?
Vagus nerve carries impulses to SA, AV nodes, releases acetylcholine
Decreases HR below intrinsic HR
What extrinsic control of heart activity occurs with sympathetic nervous system?
Carries impulse to SA, AV nodes, releases Norepinephrine, depolarizes, increases HR above intrinsic
What is the maximal HR?
250 bpm
What is bradycardia?
HR under 60 bpm in an UNTRAINED person.
What is Tachycardia and examples of how it occurs?
Fast HR, naturally (stress), exercise, caffeine
What is a PVC?
Premature Ventricular Contraction, extra beat
What is torsional contraction?
During systole the heart twists gradually like a spring, filling up the left side as much as possible.
When does abrupt untwisting occur that allows atrial filling?
Diastole
What is hemodynamics?
Blood Flow
What are 4 examples of resistance that opposes flow?
- Vasodilation
- Vasoconstriction
- Blood clots
- Plaques
Easiest way to change flow?
Change R
What are 3 things that blood does?
- Transportation
- Temperature regulation
- Acid-base- (pH) balance
What is whole blood composed of?
Plasma and Formed Elements
Will men or women carry more blood in volume?
Men (5-6L)
What percentage is Plasma of blood volume?
55-60%
How much can plasma decrease with dehydration?
-10%
How much can plasma increase with training and heat acclimation?
10%
What 4 parts is plasma broken down into?
90% Water
7% Protein
3% Nutrients
Ions
What are the 3 formed elements?
-RBC
-WBC
-Platelets
What is hematocrit?
Total percentage of volume composed of formed elements.