Health Science EKG Study

What is Sinus Rhythm?

Normal beat of the heart controlled by the heart's pacemaker

• 60-100bpm

What is an arrhythmia?

Abnormal cardiac rhythm that can happen anytime the electrical activity in the heart is changed

What is brachycardia?

Slow heart rate 60bpm or lower

What is tachycardia?

Faster heart rate of 100bpm or higher

How can cells primarily gain nutrients and excrete waste?

Diffusion, which happens over short distances.
- Means that cells must be within 2 cells of a blood vessel

What seven things does our circulatory system do for us?

- Transport nutrients
- Transport hormones
- Transport gases
- Transport wastes from throughout the body
- Regulates temperature
- Forms blood clots to prevent blood loss
- Protects the body against bacteria and viruses

3 Parts of the circulatory system

- Heart, to pump fluid
- Vessels
- blood vessels to carry fluid
- Blood
- Fluid to carry nutrients and waste

How many chambers does the heart have?

Four
- Birds/lizards have 3, fish have 2

How are the four chambers of the heart separated?

- Two halves, right and left
- Each half has two parts, an atrium and a ventricle

What do the atrium/atria do?

- Receive blood into heart
- Smaller than ventricles since just need to pump hard enough to reach ventricles, which are right beside them

What do the ventricles do?

- Send blood out of heart to body
- Due to this they need larger muscles and are bigger than the atriums

What separates the atria and ventricles?

Valves separate the atria and ventricles as well as the ventricles and the passages away from the heart

What is the one place where arteries carry deoxygenated blood and oxygenated blood?

The pulmonary cycle

Why does the left ventricle have thicker muscle wall around it than the right ventricle?

It pumps to the whole body, not just the lungs

What is the path of blood through the heart?

- 1. Blood from body
- 2. Right atrium
- 3. Right ventricle
- 4. Send blood to lungs
- 5. Blood from lungs
- 6. Left atrium
- 7. Left ventricle
- 8. Blood to body
- 9. Repeat

What keeps blood flowing the right direction in the heart?

Valves

What valves are between the atria and ventricles?

- Atrioventricular valves
- Mitral valve on the left
- Tricuspid on the right

What valves are leaving the ventricles?

- Semilunar valves
- Aortic valve on the left side
- Pulmonary valve on right side

What is the heart's beat controlled by?

- Two electrical nodes (Pacemakers)
- Sinoatrial(SA) node on atriums
- Sends electric pulse to atriums causing them to beat
- Then send signal to atrioventricular node, which sends electrical pulse through purkinje fibres, causing heart to beat
- This is why lub-dub sound

What are arteries?

- Blood leaves heart in large, wide vessels called arteries
- Thick and elastic to accommodate increase of blood pressure right after heart beats
- Arteries means AWAY

What are arterioles?

- Arteries branch into smaller vessels called arterioles
- Smaller arteries
- Branch into capillaries

What are capillaries?

- Smaller than blood cell (5-10nm vs 7nm)
- Blood cells go through one at a time to increase rate of diffusion
- Thin walls
- This is where oxygen and carbon dioxide are exchanged
- Then empty into slightly larger vessels called venules

What are venules?

- Venules are to veins as arterioles are to arteries
- Empty into larger vessels called veins which empty into heart

What are veins?

- Carry blood under lower pressure
- So they have thinner walls and have valves to keep them flowing in right direction

What is blood composed of?

- Fluid: Plasma (55%) - Clear portion
- Cellular components (45%)
- Red blood cells (Erythrocytes)
- White blood cells (Leukocytes)
- Platelets

What is surrounding red blood cells?

- Protein called antigen, used to identify blood as its own
- Two kinds: A and B, with O as absence
- A and B are co-dominant and O is recessive

What else is found in blood?

- Other antigens
- Next most important is Rhesus factor or Rh factor
- Can be present(Rh positive) or absent(Rh negative)
- Named after Rhesus monkey where it was discovered

What are the two factors of blood?

- ABO type
- Rh factor

What is heart disease?

- Heart needs oxygen and nutrients as it is a muscle
- Anything that interferes with heart's ability to pump blood - Could be caused by heart or something wrong with blood

Common heart diseases

- Myocardial infarction: heart attack, blood flow to heart is cut off
- Angina: blood flow to heart is partially of fully blocked
- Coronary artery diseases: When the arteries to the heart are blocked
- Arrhythmia: irregular heartbeat
- Atherosclerosis: Hardening of arteries
- Congestive heart failure: Heart not strong enough to pump blood, blood backs up
- Hypertension: High blood pressure
- Stroke: When a blood vessel gets blocked (In brain)
- Aneurysm: Blood vessel wall weakens and bulges out

What is blood disease?

- Anything that affects cells of blood or how they work
- Anemia: Red blood cells don't transport enough oxygen
- Hemophilia: Blood doesn't clot properly so excessive bleeding
- Leukemia: Cancer of the blood cells, specifically leukocytes

Ways to diagnose heart conditions?

- Stethoscope: Listening to heartbeat to see if it is right
- Electrocardiogram: Recording of electrical activity in heart - Symptoms: Certain symptoms that we look for

How are blood conditions diagnosed?

- Analyzing the blood
- Done as a result of symptom being present

Most common type of EKG

- Anterior 12 lead EKG
- Records electrical signal with 12 different electronic patches

Parts of standard EKG

- P wave: Beating of atriums
- QRS complex: Beating of ventricles
- T wave: Resetting of ventricles

What do doctors look for in an ECG?

- All components there
- Consistent intervals
- Clear abnormalities

Signs of stroke:

- F: Face. Is one side drooping?
- A: Arm. Do they have arm weakness?
- S: Speech. Is their speech slurred?
- T: Time. Call 911

Signs of heart attack

- Chest pain or discomfort
- Weak or lightheaded or dizzy
- Pain or discomfort in jaw, neck, back, arm or shoulders
- Shortness of breath or nausea

Medications taken

- Blood thinners: Prevents clots from happening and may be taken if there is a risk of clots
- Nitroglycerin: Helps regulate heartbeat
- Iron supplements: Help with low iron anemia

Lifestyle changes for health

- Healthy diet: Low fat, lots of veggies and fruits. Goal is to lower cholesterol
- More exercises to strengthen the heart and healthier weight. Takes more effort to pump through fatty tissue
- Reduce stress

Kinds of surgery

- Blocked vessel: Insert a stent, which is a small mesh that reinforces the blood vessel's walls
- Valves: Can replace valves inside heart with animal, human or mechanical one
- Blocked coronary artery: Can be bypassed by attaching blood vessels that go around blockage
- Heart transplants

What is the pulmonary system?

- Carries blood from heart to lungs
- Pulmonary means of the lungs
- Deoxygenated blood leaves the right ventricle through the pulmonary arteries
- Oxygenated blood returns through the pulmonary veins

What is systematic circulation?

- Part that carries blood between heart and body - Oxygenated blood leaves left ventricle through aorta
- Deoxygenated blood returns through veins into right atrium

What is the largest artery?

- The aorta, which receives blood directly from the heart

What is the largest vein?

- Inferior vena cava, which carries blood from lower body to heart
- Superior vena cava carries blood from upper body to heart

How do blood vessels help regulate processes?

- Becoming constricting (narrower) and dilating(wider)
- Happens in response to signals from autonomic nervous system or endocrine system
- Allows body to change amount of blood going to different parts of the body