ECG

Question 1

what leads supply the septal heart

Answer 1

V1, V2

Question 2

what leads supply the anterior heart

Answer 2

V3, V4

Question 3

what leads supply the apical/lateral heart

Answer 3

V5, V6

Question 4

what leads supply the lateral heart

Answer 4

L1, aVL

Question 5

what leads supply the inferior heart

Answer 5

L2, L3, aVF

Question 6

How much is each small square in ECG worth

Answer 6

0.04s

Question 7

How much is each large square in ECG worth

Answer 7

0.2s

Question 8

What leads does the LAD supply

Answer 8

V1-V4

Question 9

What occurs if the LAD is blocked

Answer 9

HF

because the LAD suppies the powerhouse of the heart

Question 10

What leads does the LCx supply

Answer 10

L1, AVL + V5, V6

Question 11

what artery supply leads L2, L3, AvF

+ SAN, AVN

Answer 11

RCA&raquo_space; obstruction of this artery leads to heart block

Question 12

How must you present an ECG (order of things)

Answer 12

1. Patient details + indictions + prior ECG
2. Rate
3. Rhythm
4. Axis
5. P wave
6. PR interval
7. BBB
8. QRS complex
9. T wave
10. ST segment
11. QT interval

Question 13

How do you count rate

Answer 13

number of R waves on rhythm strip x 6
OR
300/ number of large squares betweeen R waves

Question 14

How do you assess rhythm

Answer 14

P waves before every QRS? > sinus

regular? if not, is it IRregularly irreg or regularly irreg

Question 15

What can cause a regularly irreg rhythm

Answer 15

heart block second degree

Question 16

what causes an irreg irreg rhytm

Answer 16

SVT (AF, AFlut)

VF, torsade

Question 17

What is a common cause of a bradicardia

Answer 17

Heart block (esp 1st degree, which is regular)

Question 18

How do you determine AXIS

Answer 18

look at LI and LII:

• if they Leave > LEFT AXIS DEVIATION
• if they Reach for each other > RIGHT axis deviation

Question 19

causes of right axis deviatino

Answer 19

normal in children and skinny adults
lateral MI
RVH

Question 20

causes of left axis dev

Answer 20

LBBB
inferior MI
pacemaker rhythm

(LVH does NOT cause Left axis deviation because even as it enlarges the rhythm keeps going the normal direction)

Question 21

What causes an abnormal P wave

Answer 21

Tall peaked P wave - Pulmonary HTN, cor pulmomale

Question 22

How long is a prolonged PR interval?

Answer 22

> 0.2 seconds

Question 23

What is a first degree HB

Answer 23

PR interval prolonged but constant

Question 24

What is second degree HB

Answer 24

Mobitz T1: progressive prolongation of PR, drops, cycle restarts

Mobitz T2: occasional P not followed by QRS at a ration (e.,g. 2:1, 3:1)

Question 25

What is third degree HB

Answer 25

complete HB with P and QRT occurring independently

Question 26

What is left an right BBB

Answer 26

look at V1 and V6 Left BBB: WiLLiaM Right BBB : MaRRoW

Question 27

What abnormality can be detected in QRS compex?

Answer 27

WIDE >0.12 s | due to BBB, pacmaker, hyperkalaemia

Question 28

What causes an inverted T wav?

Answer 28

post MI

Question 29

What causes a tall and tented T wav

Answer 29

``` hyperacyte MI (early stemi) hyperkalaemia ```

Question 30

what are causes of ST elevation

Answer 30

Full thickness MI prinzmetal angina, coronary spasm Pricarditis

Question 31

What causes ST depression

Answer 31

Partial thicknss MI (NSTEMI) unstable angiina digoxin doxcity

Question 32

what are causes of prolonged QT interval

Answer 32

congential channelopathies meds e.g. SSRI metabolic e.g. hypokalaemia, hypocalcaema

Question 33

How does ventricular tachy present

Answer 33

WIDE QRS (broad complex tachy) Rate > 120 REGULAR

Question 34

Ventricular fibrillation on ECG

Answer 34

irregular broad complex tachy extremely IRREGULAR HR 300-600

Question 35

how does PE present on ECG

Answer 35

usually normal sinus tachycardia RBBB due to R heart strain S1Q3T3 (S wave in lead I, Q wave and inverted T wave in lead III)

Question 36

how does hyperkalaemia present on ECG

Answer 36

tall and tented T wave flattened P wave Broad QRS

Question 37

what condition presents with a short PR interval and why?

Answer 37

WPW

Question 38

HOw does WPW preseent on ECG

Answer 38

``` short PR interval delta wave (slurred upstroke of QRS complex - due to accessory pathway early firing) ```

Question 39

what do you see in a posterior MI

Answer 39

tall R waves in V1, V2

Question 40

when should you worry a QT is prolonged?

Answer 40

when >0.5