Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

ECG > ECG > Flashcards

ECG Flashcards

(65 cards)

Start Studying
1
Q

What do p-waves represent?

A

atrial depolirisation

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

What does the PR interval represent?

A

Represents the time taken for electrical activity to move from atria to ventricles

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

What does the QRS complex represent?

A

Depolarisation of the ventricles

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

What does the ST segment represent?

A

The time between depolarisation and repolarisation of the ventricles ie - ventricular contraction

Should be isoelectric

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

What does the T wave represent?

A

Ventricular repolarisation

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

What does the QT interval represent

A

The time taken for the ventricles to depolarise and then repolarise.

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

List the chest leads and the view of the heart each one has

A

V1 – Septal view of heart

V2 – Septal view of heart

V3 – Anterior view of heart

V4 – Anterior view of heart

V5 – Lateral view of heart

V6 – Lateral view of heart

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

List the other, non-chest leads and the view of the heart each one has

A

Lead I – Lateral view (RA-LA)

Lead II – Inferior view (RA-LL)

Lead III – Inferior view (LA-LL)

aVR – Lateral view (LA+LL – RA)

aVL – Lateral view (RA+LL – LA)

aVF – Inferior view (RA+LA – LL )

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What does a small square represent?

A

0.04 seconds

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

What does a large square represent?

A

0.20 seconds

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

How many squares are 1 second

A

5 large squares

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

How many squares are 1 minute?

A

300 large squares

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

Which leads can you read cardiac axis from?

A

Leads I II III

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

What is the normal cardiac axis degrees?

A

-30 to +90

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

Which lead should be the most deflected one NORMALLY?

A

Lead II

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

Which lead is the most deflected one in RIGHT axis deviation?

A

Lead III

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Which lead is the most deflected one in LEFT axis deviation?

A

Lead I

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What does Right axis deviation mean?

A

Right ventricular hypertrophy

It’s also a normal finding in really tall people

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What does Left axis deviation mean?

A

Usually caused by conduction defects and not by increased mass of the left ventricle.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

List the 9 steps on interpreting an ECG

A
  1. INTRO
  2. HR
  3. Rhythm
  4. Axis
  5. P waves
  6. PR interval
  7. QRS
  8. ST interval
  9. T waves
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What do you need to state in the INTRO?

A

Name and DOB

Date and Time

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

How do you calculate HR on an ECG?

A

300/number of large squares between RR intervals

eg: 300/4=75bpm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

How do you calculate HR on an ECG when the rhythm is irregular?

A

Count the number of QRS complexes on the rhythm strip and multiply by 6

each rhythm strip is 10seconds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

How do you calculate heart RHYTHM on an ECG?

A

Mark out several consecutive R-R intervals on a piece of paper, then move them along the rhythm strip to check if the subsequent intervals are the same.

Regularly irregular (i.e. a recurrent pattern of irregularity)

Irregularly irregular (i.e. completely disorganised)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
How do you calculate Cardiac axis on an ECG?
To determine the cardiac axis you need to look at leads I,II and III. Most deflected lead and meaning: I - LAD II - Normal III - RAD
26
When looking at p waves on an ECG what do you have to look for?
Are p waves present? | Is each p wave followed by a QRS?
27
What are ECG findings for AF?
Absent p waves | Irregularly irregular rhythm
28
Whats the normal PR interval duration?
120-200ms | 3-5 small squares
29
What does a prolonged PR interval suggest?
AV delay
30
What are the findings of FIRST degree heart block on ECG?
First degree heart block involves a fixed prolonged PR interval (>200 ms, >5 small squares)
31
What are the findings of SECOND degree heart, Mobitz type I, block on ECG?
PR interval slowly increases then there is a dropped QRS complex (beat).
32
What are the findings of SECOND degree heart, Mobitz type II, block on ECG?
The PR interval is fixed but there are dropped beats.
33
What are the findings of THIRD degree heart block on ECG?
The P waves and QRS complexes are completely unrelated
34
Whats the anatomical location of a FIRST degree heart block?
Occurs between the SA node and the AV node (i.e. within the atrium)
35
Whats the anatomical location of a SECOND degree heart block, Mobitz I ?
Occurs IN the AV node. This is the only piece of conductive tissue in the heart which exhibits the ability to conduct at different speeds
36
Whats the anatomical location of a SECOND degree heart block, Mobitz II?
Occurs AFTER the AV node in the bundle of His or Purkinje fibres
37
Whats the anatomical location of a THIRD degree heart block?
Occurs anywhere from the AV node down causing complete blockage of conduction
38
What does a shortened PR interval indicate?
Simply, the P-wave is originating from somewhere closer to the AV node so the conduction takes less time (the SA node is not in a fixed place and some people’s atria are smaller than others!) The atrial impulse is getting to the ventricle by a faster shortcut instead of conducting slowly across the atrial wall. This is an accessory pathway and can be associated with a delta wave (see below which demonstrates an ECG of a patient with Wolff Parkinson White syndrome)
39
What does a delta wave indicate?
Wolff parkinson white syndrome
40
What aspects of the QRS complex should you asses?
Width Height Morphology
41
What is the normal width of a QRS complex?
0.12 s | 3 small squares
42
What does a narrow QRS complex indicate?
Could indicate an atrial ectopic beat
43
What does a broad QRS complex mean?
An abnormal depolarisation sequence – for example, a ventricular ectopic where the impulse spreads slowly across the myocardium from the focus in the ventricle. A bundle branch block results in a broad QRS because the impulse gets to one ventricle rapidly down the intrinsic conduction system then has to spread slowly across the myocardium to the other ventricle.
44
What is the normal height of a QRS complex?
Limb leads: 5mm | Chest leads: 10mm
45
What do tall QRS complexes imply?
Ventricular hypertrophy or due to being tall and slim - normal.
46
What does the delta wave indicate regarding electrical activity?
Its a sign that the ventricles are being activated earlier than normal from a point distant to the AV node. The early activation then spreads slowly across the myocardium causing the slurred upstroke of the QRS complex.
47
What is diagnostic of Wolff Parkinson White syndrome on an ECG?
Delta waves | AND tacchyarrhythmias
48
How does a pathological Q wave appear on ECG?
A pathological Q wave is > 25% the size of the R wave that follows it or > 2mm in height and > 40ms in width.
49
What are normal finding for R waves on ECG?
R wave progression across chest leads V1-V6
50
When should the transition of S>R to S
V3 or V4
51
What does poor R wave progression indicate?
Previous MI Can also occur in very large people due to lead position
52
What is the J point segment?
The J point is where the S wave joins the ST segment
53
What should a ST segment look like normally?
Isoelectric line
54
When is ST elevation significant?
When its greater than 1mm in 2 or more contiguous limn leads OR When its greater than 2mm in 2 or more chest leads
55
What does ST elevation indicate?
It is most commonly caused by acute full thickness myocardial infarction.
56
What does ST depression indicate?
Myocardial Ischaemia
57
When are T waves deemed TALL?
T waves are tall if they are: > 5mm in the limb leads AND > 10mm in the chest leads (the same criteria as ‘small’ QRS complexes)
58
What are tall T waves associated with?
``` Hyperkalaemia (“Tall tented T waves”) Hyperacute STEMI (as in the very early stages of STEMI) ```
59
What do inverted T waves indicate?
Ischaemia Bundle branch blocks (V4 – 6 in LBBB and V1 – V3 in RBBB) Pulmonary embolism Left ventricular hypertrophy (in the lateral leads) Hypertrophic cardiomyopathy (widespread) General illness Around 50% of ITU admissions have some evidence of T wave inversion during their stay THIS ECG FINDING SHOULD BE APPLIED IN CONTEXT OF THE PATIENT
60
Where are T waves normally inverted?
T waves are normally inverted in V1 and inversion in lead III is a normal variant
61
What do biphasic T waves indicate?
Biphasic T waves have two peaks and can be indicative of ISCHAEMIA AND HYPOKALEMIA
62
What do flattened T waves indicate?
Another non-specific sign, this may represent ischaemia or electrolyte imbalance.
63
What are U waves?
The U wave is a > 0.5mm deflection after the T wave best seen in V2 or V3. Not common.
64
When do U waves appear?
These become larger the slower the bradycardia – classically U waves are seen in various electrolyte imbalances or hypothermia, or antiarrhythmic therapy (such as digoxin, procainamide or amiodarone).
65
List the coronary territories
Inferior (right coronary artery): II, III, aVF Anterior (left anterior descending): V1-V5 Lateral (left circumflex): I, aVL, V5/6 Posterior (posterior descending): tall R wave + ST depression in V1-3

ECG (1 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions