evaluation and initial treatment of supraventricular tachycardia
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Evaluation and Initial Treatment of Supraventricular Tachycardia
2012;367:1438-48.
CLINICAL PRACTICE
Atrial fibrillation (AF)
Underlying causes
Cardiac disease, pulmonary disease, pulmonary embolism, hyperthyroidism, postoperative
RegularityIrregular
Rate (bpm)100-220
OnsetSudden or gradual (if in chronic AF)
Response to AdenosineTermination of tachycardia
Atiral Activity and P:QRS RelationshipFibrillatory waves, no relationship to QRS
ECG
Multifocal atrial tachycardia (MAT)
Underlying causes
Pulmonary disease, theophylline therapy
RegularityIrregular
Rate (bpm)100-150
OnsetGradual
Response to AdenosineNone
Atiral Activity and P:QRS RelationshipChanging P morphologic features before QRS
ECG
Frequent atrial premature contractions
Underlying causes
Caffeine, stimulants
RegularityIrregular
Rate (bpm)100-150
OnsetGradual
Response to AdenosineNone
Atiral Activity and P:QRS RelationshipP before QRS
ECG
Sinus tachycardia
Underlying causes
Sepsis, hypovolemia, anemia, pulmonary embolism, pain, fear, fright, exertion, myocardial ischemia, hyperthyroidism, heart failure
RegularityRegular
Rate (bpm)220 minus the patient’s age
OnsetGradual
Response to AdenosineTransient slowing
Atiral Activity and P:QRS RelationshipP before QRS
ECG
Atrial flutter (AFL)
Underlying causes
Cardiac disease
RegularityRegular (occasionally irregular if variable AV conduction)
Rate (bpm)
150
OnsetSudden
Response to AdenosineTransient slowing of ventricular rate
Atiral Activity and P:QRS RelationshipFlutter wave, usually 2:1
ECG
AV nodal reentrant tachycardia (AVNRT)
Underlying causesNon
RegularityRegular
Rate (bpm)150-250
OnsetSudden
Response to AdenosineTermination of tachycardia
Atiral Activity and P:QRS RelationshipNo apparent atrial activity or R’ at termination of QRS
ECG
AV reciprocating tachycardia (AVRT)
Underlying causesRarely, Ebstein’s anomaly
RegularityRegular
Rate (bpm)150-250
OnsetSudden
Response to AdenosineTermination of tachycardia
ECGIn narrow complex, P after QRS
In wide complex, P rarely observed
In irregular rhythm (Afib), no apparent P wave
Atrial tachycardia (AT)
Underlying causesCardiac disease, pulmonary disease
RegularityRegular
Rate (bpm)150-250
OnsetSudden
Response to AdenosineTermination of tachycardia
Atiral Activity and P:QRS RelationshipP before QRS
ECG
Irregular SupraventricularTachycardiasRegularSupraventricularTachycardias
Differential Diagnosis of Supraventricular Tachycardias
The initial differential diagnosis of supraventricular tachycardias should focus on the ventricular response characteristics of regularity, rate, and rapidity of onset, not on the atrial depolarization from the ECG.
The regular supraventricular tachycardias include sinus tachycardia, atrial flutter, atrioventricular nodal reentrant tachycardia, atrioventricular reciprocating tachycardia, and atrial tachycardia.
The irregular supraventricular tachycardias are atrial fibrillation, atrial flutter with variable atrioventricular block, and multifocal atrial tachycardia; multiple atrial premature contractions can cause a similar presentation.
Differential Diagnosis of Supraventricular Tachycardias
Sudden onset and termination are characteristic of acute atrial fibrillation and atrial flutter, atrioventricular nodal reentrant tachycardia, atrioventricular reciprocating tachycardia, and atrial tachycardia.
Gradual onset and recession occur with sinus tachycardia, chronic atrial fibrillation and atrial flutter, multifocal atrial tachycardia, and atrial premature contractions.
Differential Diagnosis of Supraventricular Tachycardias
Adenosine blocks the atrioventricular node and is useful in distinguishing among supraventricular tachycardias but should not be given in the case of irregular wide-complex tachycardias, since it may render these rhythms unstable.
After administration of adenosine, slowing of the heart rate is consistent with a diagnosis of sinus tachycardia, atrial tachycardia, atrial fibrillation, or atrial flutter, whereas termination of tachycardia points to atrioventricular nodal reentrant tachycardia, atrioventricular reciprocating tachycardia, and some atrial tachycardias.
Differential Diagnosis and Treatment of Narrow-Complex Tachycardias.
Narrow-complex tachycardia
Regular rhythm Irregular rhythm
Sudden onset Gradual onset HR <150 bpm HR 150 bpm≧�
Adenosine ST AF, MAT, NSR,or ST with APCs
AF, AFL withvariable block
Termination No termination Treat underlying cause
AVNRT, AVRT, AT
AT, AFL (ST,less frequently)
Rate control with β-blocker, verapamil, diltiazem; if unstable condition, cardioversion, procainamide, ibutilde
Differential Diagnosis and Treatment of Wide-Complex Tachycardias.
Wide-complex tachycardia
Underlying heart disease
No Yes
Irregular rhythm Regular rhythm
Unstable condition Stable condition Stable condition Unstable condition
PolymorphicVT, VF
AF with WPW
AF with aberrancyor AF with benignWPW
Adenosine
Termination No termination VTCardioversion–defibrillation
SVT with aberrancy,AVRT (WPW),idiopathic VT
Cardioversion; IVprocainamide,sotalol, lidocaine,or amiodarone
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