Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

HHP > Heart & ECG > Flashcards

Heart & ECG Flashcards

1
Q

What is the role of the heart?

A
  • pumps blood through vessels to many organs
  • blood transports O2 and nutrients and removes waste CO2
  • performs sensory and endocrine functions which regulate variables in the heart such as blood volume and pressure

ULTIMATE ROLE - “to provide adequate blood flow to all of the organs and tissues of the body”

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the role of the right atrium?

A

Removes blood from systemic circuit

systemic = bodily

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the role of the right ventricle?

A

Pumps blood to pulmonary circuit

pulmonary = lungs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the role of the left atrium?

A

Receives blood from pulmonary circuit

pulmonary = lungs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the role of the left ventricle?

A

Pumps blood to systemic circuit

systemic = bodily

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are the role of the valves?

A
  • Allows for uniderectionality.

- Maintains pressure in the heart

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the septum?

A

muscle that separates the right and left atria.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Describe the route of blood through the heart.

A
  1. Deoxygenated blood enters the right atria through superior and inferior vena cava.
  2. Blood enters the right ventricle through the the atrio-ventricular valve into the right ventricle.
  3. Blood exits the right ventricle into the pulmonary artery though the semi lunar valve.
  4. Blood travels to the lungs where it becomes oxygenated and releases CO2.
  5. Blood travels from the lungs to the left atrium though the pulmonary vein.
  6. Blood travels from the left atria to the left ventricle through the atrioventricular valve.
  7. Blood travels from the left ventricle to the aorta through the semi lunar valve.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Define Myogenic

A

Signals itself- doesn’t require input from the brain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Define Autorhythmicity

A

Generates its own rhythm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are Pacemaker cells

A

Spontaneously create action potentials.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Define Systole

A

The phase of the heartbeat when the heart muscle contracts and pumps blood from the chambers into the arteries.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Define Diastole

A

The phase of the heartbeat when the heart muscle relaxes and allows the chambers to fill with blood.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are contractile cells

A

They are responsible for contraction of the heart muscle.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Where are pacemaker cells located?

A

Located in the SAN (found in the upper right atrium) And in the atrioventricular node (found near the tricuspid valve in inter-atrial septum)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What do conduction fibres do?

A

conduct the action potential through the myocardium. The action potential travels of speeds of 4m/s. Conduction fibres have low electrical resistance

17
Q

What forms the conduction system of the heart

A

Pacemaker cells+ conduction fibres= conduction system of the heart

18
Q

what is the passage of an action potential

A

pacemakers –> conduction fibres –> contractile cells, this is possible because all cardiac cells are connected by gap junctions, inside intercalated disks

19
Q

what are desmosomes, where are these found?

A

protein fibres which form physical bonds between cells to resist mechanical stress. This enables myocardium to resist stretching, as occurs every time heart fills with blood
found inside Intercalated disks

20
Q

Describe the Initiation and Conduction of an Impulse during a Heartbeat

A

1) Impulse initiated in SA node –> AV node via conduction fibres and through most of atrial muscle
2) AV node transmits AP less rapidly, therefore delayed by 0.1 seconds
3) AV node –> atrioventricular bundle (bundle of His) in interventricular septum
4) Signals split into left and right branches to ventricles
5) From the bundle branches, signals travel through a network of branches known as Purkinje fibres which spread through ventricular myocardium

21
Q

Describe the electrical activity in pacemaker cells

A
  • Pacemaker cells fire AP spontaneously - doesn’t have a steady resting potential.
  • After AP, pacemaker cell immediately depolarises slowly until membrane potential reaches threshold, which triggers next AP.
  • Slow depolarisations are known as pacemaker potentials
  • Changes in membrane permeability to different ions.
22
Q

Cardiac contractile cells -

A
  • Responsible for the contraction of the heart.

- The depolarisation/repolarisation of these cells are different to the pacemaker cells.

23
Q

What does an Electrocardiogram (ECG) record?

A

• “Records the spread of electrical current through the heart as a function of time through the cardiac cycle.”

24
Q

What is Einthoven’s triangle

A

 Equilateral triangle surrounding the heart.
 Right arm, left arm and left leg.
 Electrodes are connected to an oscilloscope.

25
Q

Arrhythmias -

A 
Irregular heartbeat caused by abnormal SA firing which can cause fast (more than 100 bpm) 
Or slow (less than 50 bpm) heart rates
26
Q

Problems with the conduction through the AV node can cause problems such as…

A
  1. Third degree block - no conduction though the AV node causing dissociation between atrial and ventricular contractions, potentially lethal.
  2. Depolarisation can occur from electrical signal outside the conduction pathway, causing PAC or PVC (pre atrial and pre ventricular contraction). Not usually significant
  3. Ventricular fibrillation: no longer synchronised heart beats. Can’t pump blood efficiently round body. Deadly. Atrial fibrillation: weakness but not deadly and the problems associated are not as significant as ventricular fibrillations. , as ventricles still contract sufficiently
27
Q

P wave

A

atrial depolarisation

28
Q

QRS complex

A

ventricular depolarisation

29
Q

T wave

A

ventricular repolarisation

30
Q

p-q interval

A

AV node conduction time

31
Q

q-t interval

A

ventricular systole

32
Q

t-q interval

A

ventricular diastole

33
Q

r-r interval

A

time between heart beats

34
Q

how is data recorded in an ecg

A

• Data is recorded via electrodes placed in the skin at certain parts of the body.

35
Q

What does the ECG tell you?

A

It breaks down each heartbeat into a series of electrical waves, P wave, QRS complex and T wave.

36
Q

What does the sinoatrial node do?

A

Sets the time and rate at which the cardiac muscle cells contract

37
Q

What can ECG’s be influenced by?

A

Nerves, hormones, body temperature, exercise etc.

38
Q

How can you tell if the activity of an ECG is well synchronised

A

• If the activity is well synchronised, the amplitude of the peaks are larger.

HHP (2 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions