Accelerated idioventricular rhythm: Difference between revisions
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==Background== | ==Background== | ||
[[File:SinusRhythmLabels.svg|thumb]] | |||
[[File:ConductionsystemoftheheartwithouttheHeart-en.png|thumb|Conduction system of the heart.]] | |||
*Results when rate of an ectopic ventricular pacemaker exceeds sinus node | *Results when rate of an ectopic ventricular pacemaker exceeds sinus node | ||
*Usually benign,self limiting | *Usually benign,self limiting | ||
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==Differential Diagnosis== | ==Differential Diagnosis== | ||
{{Tachycardia (wide) DDX}} | |||
{{Palpitations DDX}} | {{Palpitations DDX}} | ||
==Evaluation== | ==Evaluation== | ||
[[File:AIVR from the LV.png|thumb|Accelerated idioventricular rhythm (AIVR) at a rate of 55/min presumably originating from the left ventricle (LV). Note the typical QRS morphology in lead V1 characteristic of ventricular ectopy from the LV. Monophasic R-wave with smooth upstroke and notching on the downstroke (i.e., the so-called taller left peak or "rabbit-ear".)]] | |||
===[[ECG]] features=== | ===[[ECG]] features=== | ||
*Regular rhythm | *Regular rhythm | ||
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*AIVR is a benign rhythm in most settings and does not usually require treatment | *AIVR is a benign rhythm in most settings and does not usually require treatment | ||
*Self limiting and resolves when sinus rate exceeds that of the ventricular foci | *Self limiting and resolves when sinus rate exceeds that of the ventricular foci | ||
* | *[[Antiarrhythmics]] may cause precipitous haemodynamic deterioration and should be '''avoided''' | ||
*Treat the underlying cause: e.g. correct electrolytes, restore myocardial perfusion | *Treat the underlying cause: e.g. correct electrolytes, restore myocardial perfusion | ||
*Patients with low-cardiac-output states (e.g. severe biventricular failure) may benefit from restoration of AV synchrony to restore atrial kick – in this case atropine may be trialled to increase sinus rate and AV conduction | *Patients with low-cardiac-output states (e.g. severe biventricular failure) may benefit from restoration of AV synchrony to restore atrial kick – in this case [[atropine]] may be trialled to increase sinus rate and AV conduction | ||
==Disposition== | ==Disposition== | ||
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==See Also== | ==See Also== | ||
*[[ECG]] | |||
==External Links== | ==External Links== | ||
*http://lifeinthefastlane.com/ecg-library/aivr/ | *[http://lifeinthefastlane.com/ecg-library/aivr/ LITFL - Accelerated Idioventricular Rhythm (AVIR)] | ||
==References== | ==References== | ||
Latest revision as of 03:33, 8 January 2022
Background
- Results when rate of an ectopic ventricular pacemaker exceeds sinus node
- Usually benign,self limiting
- Terminology
- Idioventricular rhythm: 20-40 bpm
- Accelerated idoventricular rhythm: 40-120 bpm
- Ventricular tachycardia: >120 bpm
Causes
- Reperfusion phase of acute myocardial infarction (most common cause)
- Beta-sympathomimetics (isoprenaline or adrenaline)
- Drug toxicity, especially digoxin, cocaine and volatile anaesthetics such as desflurane
- Electrolyte abnormalities
- Cardiomyopathy
- congenital heart disease
- myocarditis
- Return of spontaneous circulation (ROSC) following cardiac arrest
- Athletic heart
Clinical Features
- Asymptomatic or palpitations
Differential Diagnosis
Wide-complex tachycardia
Assume any wide-complex tachycardia is ventricular tachycardia until proven otherwise (it is safer to incorrectly assume a ventricular dysrhythmia than supraventricular tachycardia with abberancy)
- Regular
- Monomorphic ventricular tachycardia
- PSVT with aberrant conduction:
- PSVT with bundle branch block^
- PSVT with accessory pathway
- Atrial flutter with bundle branch block^
- Sinus tachycardia with bundle branch block^
- Accelerated idioventricular rhythm (consider if less than or ~120 bpm)
- Metabolic
- Irregular
- Atrial fibrillation/atrial flutter with variable AV conduction AND bundle branch block^
- Atrial fibrillation/atrial flutter with variable AV conduction AND accessory pathway (e.g. WPW)
- Atrial fibrillation + hyperkalemia
- Polymorphic ventricular tachycardia
^Fixed or rate-related
Palpitations
- Arrhythmias:
- Non-arrhythmic cardiac causes:
- Psychiatric causes:
- Drugs and Medications:
- Alcohol
- Caffeine
- Drugs of abuse (e.g. cocaine)
- Medications (e.g. digoxin, theophylline)
- Tobacco
- Misc
Evaluation
Accelerated idioventricular rhythm (AIVR) at a rate of 55/min presumably originating from the left ventricle (LV). Note the typical QRS morphology in lead V1 characteristic of ventricular ectopy from the LV. Monophasic R-wave with smooth upstroke and notching on the downstroke (i.e., the so-called taller left peak or "rabbit-ear".)
ECG features
- Regular rhythm
- Rate 50-110 bpm
- Three or more ventricular complexes
- QRS complexes >120ms
- Fusion and capture beats
Management
- AIVR is a benign rhythm in most settings and does not usually require treatment
- Self limiting and resolves when sinus rate exceeds that of the ventricular foci
- Antiarrhythmics may cause precipitous haemodynamic deterioration and should be avoided
- Treat the underlying cause: e.g. correct electrolytes, restore myocardial perfusion
- Patients with low-cardiac-output states (e.g. severe biventricular failure) may benefit from restoration of AV synchrony to restore atrial kick – in this case atropine may be trialled to increase sinus rate and AV conduction
Disposition
- Normally outpatient