Supraventricular Tachycardias - Atrial flutter

Question 1

Definition

Answer 1

Irregular ORGANISED atrial firing 250-350bpm -
less common + less severe than AF

Question 2

Risk factors

Answer 2

Atrial fibrillation

Question 3

Epidemiology

Answer 3

Increasing Age
Female

Question 4

Pathophysiology

Answer 4

Atrial flutter is caused by “re-entrant rhythm” in either atrium. This is where the electrical signal re-circulates in a self-perpetuating loop due to an extra electrical pathway. The signal goes round and around the atrium without interruption = Fast atrial ectopic firing (250-350 bmp). The signal makes its way into the ventricles every second lap due to the long refractory period to the AV node- causing 150 bpm ventricular contraction = SAW TOOTH APPEARANCE with p wave after p wave.
Causes atrial spasm, but not as uncoordinated as A.fib = pathway typically form around tricuspid annulus (opening of valve).

Question 5

Aetiology

Answer 5

HEART FAILURE
Hypertension,
IHD
Mitral stenosis
Pneumonia
Hyperthyroidism
Hypokalaemia
Hypomagnesemia

Question 6

Signs

Answer 6

Tachycardia
Tachypnoea
Hypotension
Pallor
Cold and clammy
Signs of Pulmonary oedema
Raised JVP

Question 7

Symptoms

Answer 7

May be asymptomatic
Palpitations
SOB
Dizziness
Ischaemic chest pain
Syncope
Confusion
Sweating

Question 8

Diagnosis

Answer 8

GOLD STANDARD = ECG = F WAVE “SAW TOOTH” pattern often with 2:1 block (2 p waves for every QRS)
TFTs: hyperthyroidism
U&E’s and metabolic panel: hyperkalaemia

Question 9

Treatment

Answer 9

Acutely unstable: DC synchronised cardioversion
Stable - rhythm rate control = beta blocker with oral anticoagulation (prevent thromboemboli or radiofreq ablation
- IV Amiodarone may be needed if rate control proving difficult