Arrythmias Flashcards
What are examination findings for Atrial Fibrillation?
- Irregular irregular pulse
- Apical pulse rate is greater than the radial rate and 1st heart sounds of variable intensity
- Signs of left ventricular failure
What are tests in Atrial Fibrillation?
- ECG: show absent P waves, irregular QRS complexes
- Bloods: U&Es, cardiac enzymes, thyroid function tests
- Echocardiography for Atrial enlargement, Mitral valve disease, Left ventricular function and other structural abnormalities
What is the acute management of an Atrial Fibrillation?
- Oxygen then ITU/CCU
- Emergency electrical cardioversion if unavailable then IV amiodorane.
- Treat associated illnesses if present
What are the indications for emergency cardioversion?
- Electrical Cardioversion as an emergency if the patient is haemodynamically unstable
- Electrical or Pharmacological cardioversion as an elective procedure where a rhythm control strategy is preferred.
What is the management of Atrial Fibrillation with an onset for <48 hours who have non-lifethreatening haemodynamic instability?
- Patient heparinised with LMWH
- Patients may be cardioverted. Following electrical cardioversion if AF is confirmed as being less than 48 hours duration then further anticoagulation is unnecessary
- Patients with risk factors for ischaemic stroke should be put on lifelong oral anticoagulation
How can patients be cadioverted?
1st line: Electrical ‘DC’ cardioversion
2nd line (if electrical cadioversion is not unavailable): Pharmacological cadioversion
- Amiodarone if structural heart disease.
- Flecainide or Amiodarone in those without structural heart disease
What is the management of Atrial Fibrillation with an onset for >48 hours?
- Rate control initiaited.
- If Rhythm control refferal is thought to be appropriate:
- Anticoagulation should be given for at least 3 weeks prior to cardioversion.
- An alternative strategy is to perform a transoesophageal echo (TOE) to exclude a left atrial appendage (LAA) thrombus. If excluded patients may be heparinised and cardioverted immediately.
- NICE recommend electrical cardioversion in this scenario, rather than pharmacological.
What is done if there is high risk of cardioversion failure with patients with an onset of >48 hours?
- Recommend to have at least 4 weeks amiodarone or sotalol prior to electrical cardioversion
- Following electrical cardioversion patients should be anticoagulated for at least 4 weeks
- After this time decisions about anticoagulation should be taken on an individual basis depending on the risk of recurrence
What is the ongoing treatment for rate control?
1st Line: Verapamil or Bisoprolol
2nd line: Digoxin or Amiodarone
If this doesn’t work, combination of 2 of the following can be given: beta-blocker, diltiazem, digoxin
What is the ongoing treatment for rhythm control?
- Beta-blockers
- Dronedarone in patients as an option for the maintenance of sinus rhythm after successful cardioversion in people with paroxysmal or persistent atrial fibrillation
- Consider Amiodorane for people with LV impairment or heart failure
When is rhythm control as ongoing treatment done in patients?
In patients
- Whose atrial fibrillation is not controlled by first line therapy and have at least 1
- Hypertension, Diabetes mellitus, previous TIA, Stroke or systemic embolism, left atrial diameter of 50mm or greater, age 70 years or older
- Who do not have left ventricular systolic dysfunction
- Who do not have a history of heart failure
What is done in the event of treatment failure of Atrial Fibrillation?
- Try left atrial ablation
- Pacing and atrioventriclar ablation for people with permanent atrial fibrillation and symptoms or left ventricular dysfunction thought to be cause by high ventricular rates
What is the recommendation of anticoagulation in Stroke/TIA?
- Following a stroke or TIA, Warfarin should be given as the anticoagulant of choice.
- In acute stroke patients, in the absence of haemorrhage, anticoagulation therapy should be commenced after 2 weeks. If imaging shows a very large cerebral infarction then the initiation of anticoagulation should be delayed
- Aspirin/dipyridamole should only be given if needed for the treatment of other co-morbidities
How is anticoagulation methods reversed used in major bleeding?
- Stop warfarin
- Give intravenous vitamin K 5mg
- Prothrombin complex concentrate
- if not available then fresh frozen plasma*
What is a Torsade de Pointes?
- Torsades de pointes (‘twisting of the points’) is a rare arrhythmia associated with a long QT interval.
- It may deteriorate into ventricular fibrillation and hence lead to sudden death
