Week 3 - Cardiac Rhythms

Question 1

What are the different types of cardiac rhythms?

Answer 1

• Normal Sinus Rhythm
• Arrhythmias
• Asystole
• Atrial Fibrillation

Question 2

Name 2 different types of Arrhythmias

Answer 2

Ventricular Tachycardia (VT)
Ventricular Fibrillation (VF)

Question 3

What is Ventricular Tachycardia (VT)?

Answer 3

• Ventricular Tachycardia (VT) is characterised by an absence of P waves as the ventricles have taken over - QRS complex is wide and fast
• There is initially a pulse, but VT can progress onto no palpable pulse (no cardiac output) = cardiac arrest (needs defibrillation)
• This is a life-threatening rhythm

Question 4

What is Ventricular Fibrillation (VF)?

Answer 4

• Ventricular fibrillation (VF) is characterised by rapid disorganised contraction of the ventricles = life-threatening rhythm - needs defibrillating immediately!!
• No discernible atrial or ventricular activity
• No palpable pulse (no cardiac output) or respirations = cardiac arrest
• VF is the most common arrhythmia in patients with cardiac arrest - can be because of myocardial infarction (MI)

Question 5

What is Asystole?

Answer 5

• Easiest rhythm to memorise
• Complete absence of electrical activity - straight line on the monitor
• No QRS complexes - no cardiac output
• Cessation of the heart’s functioning

Question 6

What is Atrial Fibrillation (AF)?

Answer 6

• Atrial Fibrillation (AF) - completely disorganised atrial electrical activity
• Impulses arise from the SA node and other sites in the atria
• Conduction through the AV node is irregular and usually fast
• There are no P waves and it is irregular
• Instead of a P wave - it has uneven fibrillary lines (F waves) before the QRS complex

Question 7

What are some Atrial Fibrillation Risk Factors?

Answer 7

Older age

Male gender

Obesity

Hypertension

Excessive alcohol intake

Heart Failure

Question 8

What are some signs and symptoms of Atrial Fibrillation?

Answer 8

SOB

Fatigue

Palpitations

Chest pain

Haemodynamic instability (abnormal or unstable blood pressure)

Question 9

What is the treatment for Atrial Fibrillation?

Answer 9

Depends on the cause, severity of symptoms and the pattern

Get the rate down – Beta Blockers

Control the rhythm – medication or cardioversion

Anticoagulation due to the risk of thromboembolism

Question 10

What is a 12 lead ECG?

Answer 10

• A diagnostic tool used to help identify pathological changes associated with Acute coronary syndromes (ACS) such as a myocardial infarction (MI)
• Detects the heart’s electrical activity through electrodes attached to the skin and relays them as waveforms for interpretation on graph paper
• 10 physical leads to attach to the patient showing 12 different views of the heart

Question 11

Where do the ECG leads go?

Answer 11

On the 4th intercostal space

Question 12

Name the landmarks for each ECG lead

Answer 12

• V1 should go on the right side of the sternum, where the sternum meets the rib
• V2 should go on the left side of the sternum, where the sternum meets the rib
• V4 goes on the mid-clavicular line on the 5th intercostal space
• V3 goes in the middle of V2 and V4
• V5 goes horizontally to V4 on the anterior axillary line which is furthest to the front of the side of the chest wall
• V6 goes in the mid axillary line which is on the side, vertical to the armpit
• One electrode on each arm
• Leg electrodes go somewhere down on the calves or thighs which depends on what kind of access you have to the patient’s lower extremities