c_aflutter
Table of Contents
Atrial flutter
see also: cardiology; cardiac arrhythmias; AF
Introduction:
- clinically, atrial flutter is managed similarly as for Atrial Fibrillation with which it is often in association, although of the two, AF is 7-8x more common as a cause for admission.
- often flutter is not as well tolerated as AF due to the rapid and often difficult to control ventricular rate, especially with minimal exertion.
- The common form of type I atrial flutter has sawtooth flutter (F) waves, best seen in leads II, III, and aVF, with atrial rates of 240-340 bpm and without an isoelectric interval between these F waves.
often it presents as a HR of 150 due to a atrial rate of 300 with a 2:1 block
- Variable AV conduction can also be seen (commonly present with 2:1 or 3:1 AV conduction).
- With 1:1 AV conduction, hemodynamic collapse may occur.
- 75% of patients are male
- most patients are older adults with average age 64yrs
- 30% have ischaemic heart disease
- 30% have hypertensive heart disease
- 30% have no underlying cardiac disease
- other associations:
- cardiomyopathy
- hypoxia
- COPD
- thyrotoxicosis
- phaeochromocytoma
- electrolyte imbalance
- alcohol consumption
Mx in the ED:
- general care is as for Atrial Fibrillation
haemodynamically unstable
- if rapidly deteriorating, then synchronised reversion
- if delay in access to synchronised reversion then:
- metaraminol (Aramine) 0.5mg iv over 1 minute and repeat minutely until either:
- arrhythmia reversion
- max dose 5mg metaraminol given
- systolic BP > 100
diagnosis:
- when it is not clear from the ECG, vagal manouvres or IV adenosine may block the AV node to display the underlying rhythm
- is there evidence of, or a history of a pre-excitation syndrome such as WPW - this should be determined because agents that act exclusively at the level of the AV node may enhance accessory pathway conduction and cause rapid ventricular response with 1:1 conduction and ventricular rate of 300/min which may precipitate VF.
ventricular rate control:
- can be difficult and need to watch for adverse effects of Rx such as hypotension & negative inotropic effects (cardiac failure)
- if no pre-excitation syndrome such as WPW, no other C/I (such as poor LV function) then, either:
termination of sustained episodes:
- if duration < 48hrs after cardiac consultation, DC reversion is effective in 95% & requires less energy than for AF eg. 50J synchronized
- IV amiodarone slows rate and may result in reversion
- other anti-arrhythmics
prevention:
- avoid precipitants - eg. caffeine, alcohol,
- anti-arrhythmics as for AF - consider sotalol
- referral for radiofrequency ablation or surgery if recurrent & problematic
prevention of thrombo-embolic complications:
- risk is ~14% over 4-5yrs, probably more related to unrecognised associated episodes of AF
- see AF.
c_aflutter.txt · Last modified: 2013/07/16 07:18 by 127.0.0.1