Isorhythmic A-V dissociation: Difference between revisions
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{{SK}} Isorhythmic AV dissociation | |||
==Overview== | ==Overview== | ||
Isorhythmic AV dissociation is a AV dissociation initiated by slowing of SA node due to sinus arrhythmia, sinus bradycardia, sinus arrest, or sinoatrial exit block due to bradycardia. This allows an independent ventricular pacemaker response like either junctional (giving a normal or near normal QRS appearance and duration) or idioventricular (with a more bizarre, wide QRS) rhythm to take over the ventricles. In the presence of some degree of antegrade and retrograde atrioventricular block, there is a synchronization of independently beating sinus or atrial pacemaker with the junctional or ventricular pacemaker such that each discharges in the absolute refractory period of the other. | |||
==Causes== | ==Causes== |
Revision as of 21:05, 3 September 2013
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Vendhan Ramanujam M.B.B.S [2]
Synonyms and keywords: Isorhythmic AV dissociation
Overview
Isorhythmic AV dissociation is a AV dissociation initiated by slowing of SA node due to sinus arrhythmia, sinus bradycardia, sinus arrest, or sinoatrial exit block due to bradycardia. This allows an independent ventricular pacemaker response like either junctional (giving a normal or near normal QRS appearance and duration) or idioventricular (with a more bizarre, wide QRS) rhythm to take over the ventricles. In the presence of some degree of antegrade and retrograde atrioventricular block, there is a synchronization of independently beating sinus or atrial pacemaker with the junctional or ventricular pacemaker such that each discharges in the absolute refractory period of the other.
Causes
Life Threatening Causes
Life-threatening causes include conditions which may result in death or permanent disability within 24 hours if left untreated.
- Acute coronary syndrome
- Diabetic ketoacidosis
- Myocardial rupture
- NSTEMI
- Organophosphate poisoning
- STEMI
Common Causes
- Acetylcholine
- Acute coronary syndrome
- Acute rheumatic fever
- Amiodarone
- Antiarrhythmic agents
- Beta-blockers
- Calcium channel blockers
- Cardiac catheterization
- Cardiomyopathy
- Congestive heart failure
- Digitalis toxicity
- Diltiazem
- Hypertensive heart disease
- Ischemic heart disease
- Myocarditis
- Sick sinus syndrome
- Sinus arrest
- Sinus bradycardia
- STEMI