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Question 1

How many small squares are in each large square in an ECG paper? What is the width and height of the large square

Answer 1

No. 5x5

Width and height:5mm x 5mm

Question 2

What does the Y axis of each large square represent?

Answer 2

Voltage

(bc V looks like a Y without a stick)

Question 3

How many milivolts is the Y axis of each large square?

Answer 3

0.5 mv

(so each small square it 0.1)

Question 4

How many seconds is the x axis of each large square?

Answer 4

0.20

Question 5

What does the X axis of each large square represent?

Answer 5

duration

Question 6

How many seconds is the x axis of each small square?

Answer 6

0.04 s

(bc the large square is 0.20 and there are 5 small squares, so 0.20/5= 0.04)

Question 7

How many milivolts is the Y axis of each small square?

Answer 7

**0.1 mv **

(bc the large square is 0.5, and we have 5 small squares, so 0.5/5= 0.1)

Question 8

How do you measure the exact time interval of each heart beat?

Answer 8

You count the number of small boxes (or no. of big boxes x 5) between 2 R-R intervals, then you multiply it by 0.04.

Question 9

How do you do an Exact calculation of Heart Rate from an ECG trace?

Answer 9

You calculate the R-R interval (the time of each heart beat)

then you divide 60 by it.

So if the R-R interval is 0.8, then the heart rate would be= 60/0.8 = 75 BPM

Question 10

How do estimate the heart rate from ecg?

Answer 10

300/by number of big boxes in the R-R interval

Question 11

How do you calculate the time of segments and intervals from the ecg?

Answer 11

1.Count the number of small boxes inside the interval

2. Multiply No. of boxes x 0.04

Question 12

What is the PQ/PR interval rate supposed to be?

Answer 12

0.12-0.2 seconds

Question 13

What is the QRS complex time supposed to be?

Answer 13

< 0.10 seconds

Question 14

What is the QT interval time supposed to be?

Answer 14

generally less than 0.4 s at rest

Question 15

What does the mean electrical axis indicate?

Answer 15

Indicates:
– Orientation of heart –

Size of ventricular chambers

– Conduction block

Question 16

What is the normal axis for the MEA?

Answer 16

From +90 till -30

Question 17

What is the range for the Left axis deviation of the MEA? What are the conditions that this is commonly seen in?

Answer 17

Range: -30 to -90

Conditions: Commonly seen in any condition causing
left ventricular hypertrophy, inferior STEMI

Question 18

What is the range for the Right axis deviation of the MEA? What are the conditions that this is commonly seen in?

Answer 18

Range: +90 to +180

Conditions: Normal finding in children and tall thin adults

Commonly seen in any condition causing
right ventricular hypertrophy

Question 19

What is the range for the Exterme axis deviation of the MEA? What are the conditions that this is commonly seen in?

Answer 19

Range: +180 to -90

Conditions Lateral STEMI, COPD, Dextrocardia

Question 20

How do you know if it is Right axis in ECG?

Answer 20

If lead I is negative, look at avF

Question 21

How many small squares would a normal pq interval be?

Answer 21

< 5

Question 22

What does it mean if the p wave is upside down?

Answer 22

The SA node is non functional, The av node is acting as the main pacemaker. (upside down bc the ap is spreading away from the +ve electrode)

Question 23

What is normal duration of QRS complex? How do you determine it?

Answer 23

Normal: <0.1

Determine: Look at the number of small boxes that the QRS covers. (normal in this case bc 1 box so 0.1 sec)

Question 24

What is sinus bradycardia?

Answer 24

When everything is normal except the BPM is low (less than 60)

(brad, so broad, so the spaces between the R waves will be broad)

Question 25

What is sinus **tachy**cardia?

Answer 25

When everything is normal except the BPM is High (more than 100)

Question 26

What is the first degree heart block? How do you determine that it is a first degree heart block from the ECG? What are some conditions that cause it?

Answer 26

**It is** a partial block of the av node which prolonges The PQ interval. **Diagnosis**: if the PQ interval is prologned (more than 0.20 s) and there is normal rythem P-QRS-T **Conditions:** fibrosis, Calcium channel blocking drugs enhanced vagal tone athletic training.

Question 27

What is a second degree heart block?

Answer 27

Pr interval is over 0.24 seconds, and the pre interval keeps on getting longer and longer after each contraction, until no QRS is generated.

Question 28

What are the two types of Second degree heart block?

Answer 28

Mobitz Type I Mobitz Type II

Question 29

What is **Second degree** heart block **Mobitz Type I**? How do diagnose it from the ECG? What are some conditions that this can be seen in?

Answer 29

**It is:** Partial block of the av node **Diagnosi**s:Progressive lengthening of the PR interval until not QRS is generated **conditions:** may be seen normally in children, athletes or individuals with elevated vagal tone.

Question 30

What is **Second degree** heart block **Mobitz Type II**? How do diagnose it from the ECG? What are some conditions that this can be seen in?

Answer 30

**It is:** Partial block of the **Bundle of his** (bc type II so two branches) **Diagnosi**s: Sudden loss of QRS, wide QRS (more than 1 small square) **conditions:** may be seen normally in children, athletes or individuals with elevated vagal tone.

Question 31

What is the general treatment for Second degree mobitz type II?

Answer 31

Pacemaker implantation is generally the treatment for this condition

Question 32

What is **Third degree heart block?**

Answer 32

* Complete block of AV node or Bundle of His

Question 33

What is **Third degree** heart block? How do diagnose it from the ECG?

Answer 33

**It is:**Complete block of AV node or Bundle of His **Diagnosi**s: QRS is opposite to t waves, if QRS is positive, t waves will be negative and vice versa. P-P interval is Normal, R-R is short 20-40. 2-4 p waves for every QRS.

Question 34

Where is the AP of the ventricles generated in **Third degree heart block?**

Answer 34

Purkinje-his system

Question 35

What is atrial fibrillation? How do you diagnoss it on the ecg

Answer 35

Re-entry current causes a "jittery" reading on the ECG, no clear p waves, the r-waves are very inconsistent.

Question 36

What is ventricular fibrillation? How do you diagnoss it on the ecg

Answer 36

**it is** Re-entry in ventricles **Diagnosis** Distinguishable by the total absence of any pattern

Question 37

What is Regularly regular Rhythm? What is an example?

Answer 37

The R-R intervals are the same for each heartbeat and the rhythm is maintained. (P-QRS-T is the same, even if smth is wrong with one of the parts) **(regular pattern and rhythm)** **Example** Sinus bradycardia, sinus tachycardia, first degree heart block

Question 38

What is regulary irregular Rhythm? Example?

Answer 38

Rythm that doesn't have the same R-R intervals, but has a pattern that repeats. (P-QRS-T is not consistent, but its inconsistency is repeated ) **Time:** Second degree heart block

Question 39

What is irregulary irregular Rhythm? Example?

Answer 39

No pattern, no rhythm **example** atrial fibrilation

Question 40

What is prolonged QT syndrome?

Answer 40

Prolonged QT interval due to genetic mutations.

Question 41

What is the normal duration for QT interval? What is considered as prolonged?

Answer 41

**Normal:** < 400 **Prolonged** > 450 ms in men and 470 in women