Sinus Arrhythmias

Question 1

how many leads on EASI lead ECG?

Answer 1

5-lead ECG

Question 2

positions of the 5-lead ECG

Answer 2

BROWN= lower sternum (5th ICS)
RED= left mix-axillary line (5th ICS)
BLACK= upper sternum (just below sternal angle)
WHITE= right mid-axillary line (5th ICS)
GREEN= anywhere

Question 3

ECG paper small square time

Answer 3

0.04 seconds

Question 4

ECG paper large square time

Answer 4

0.20 seconds

Question 5

five step approach to ECG rhythm strip

Answer 5

1. heart rate
2. rhythm
3. P waves
4. PR interval
5. QRS complex

Question 6

what can cause artefacts on an ECG?

Answer 6

patient movement
defective electrodes (fuzzy baseline)
improper grounding
faulty apparatus

Question 7

what does a U wave on ECG indicate?

Answer 7

hypokalaemia

Question 8

how to calculate HR on ECG

Answer 8

300/ number of small squares between R-R

number of QRS in 30 large squares x 6 ?

Question 9

what is the atrial count?

Answer 9

number of P waves in 1 minute

Question 10

what is the ventricular rate?

Answer 10

count number of QRS in 1 minute

Question 11

normal PR interval

Answer 11

0.12-0.2 seconds

Question 12

normal QRS interval

Answer 12

0.06-0.12 seconds (1.5-3 small boxes)

Question 13

five common variations in sinus rhythm

Answer 13

1. normal sinus rhythm (60-100bpm)
2. sinus bradycardia (<60bpm)
3. sinus tachycardia (>100bpm)
4. sinus arrhythmia
5. sinus pause/ arrest

Question 14

define bradycardia

Answer 14

PR interval and QRS are normal, there is just a longer pause between beats

Question 15

causes of bradycardia

Answer 15

normal in athletes
sleep
vagal manoeuvre
hypoglycaemia
hypothermia
hypothyroid
previous cardiac history
medications
toxic exposure
MI (right coronary artery, inferior wall)

Question 16

management of bradycardia

Answer 16

atropine or pacing if haemodynamically compromised

Question 17

define sinus tachycardia

Answer 17

heart rhythm over 100bpm at rest

Question 18

causes of sinus tachycardia

Answer 18

damage to heart tissues
hypertension
fever
stress
excess alcohol
caffeine
nicotine
cocaine
medication
response to pain
imbalance of electrolytes
hyperthyroidism

Question 19

what is the risk in tachycardia?

Answer 19

risk of falling CO due to inadequate ventricular filling time and myocardial demand is increased so can precipitate ischaemia and infarction

Question 20

management of narrow QRS tachycardia

Answer 20

vagal manoeuvres
adenosine
beta blockers
CCBs
synchronised cardioversion

Question 21

management of broad QRS tachycardia

Answer 21

procainamide
amiodarone
sotalol

Question 22

define sinus arrhythmia

Answer 22

rate increases with inspiration

Question 23

causes of sinus arrhythmia

Answer 23

can be normal
heart disease
stress
caffeine
nicotine
alcohol

Question 24

management of sinus arrhythmias

Answer 24

reduced CO but only treat if symptomatic

Question 25

define sinus pause/ arrest

Answer 25

transient absence of P waves that lasts 2 seconds to several minutes

Question 26

causes of sinus pause/ arrest

Answer 26

healthy hearts during sleep
myocarditis
cardiomyopathy
MI
digoxin toxicity
elderly
vagal stimulation

Question 27

risks of sinus pause/ arrest

Answer 27

sudden cardiac death
falls 
VTE events
CHF
AF

Question 28

management of sinus arrest/ pause

Answer 28

atropine

pacemaker