Supraventricular tachycardia differentiating SVT from VT: Difference between revisions
No edit summary |
|||
| (6 intermediate revisions by 2 users not shown) | |||
| Line 5: | Line 5: | ||
'''See also:''' [[Wide complex tachycardia]] | '''See also:''' [[Wide complex tachycardia]] | ||
==Overview== | ==Overview== | ||
Most supraventricular tachycardias have a narrow [[QRS complex]] on the [[EKG]]. It is not infrequent, however, for aberrant conduction to be be present, sometimes as a result of the more rapid rate of conduction. This widening of the QRS complex yields supraventricular tachycardia with aberrant conduction (SVTAC) which produces a [[wide-complex tachycardia]] that may mimic [[ventricular tachycardia]] (VT). In the clinical setting, it is important to determine whether a [[wide-complex tachycardia]] is an [[SVT]] or a | Most supraventricular tachycardias have a narrow [[QRS complex]] on the [[EKG]]. It is not infrequent, however, for aberrant conduction to be be present, sometimes as a result of the more rapid rate of conduction. This widening of the QRS complex yields supraventricular tachycardia with aberrant conduction (SVTAC) which produces a [[wide-complex tachycardia]] that may mimic [[ventricular tachycardia]] (VT). In the clinical setting, it is important to determine whether a [[wide-complex tachycardia]] is an [[SVT]] or a ventricular tachycardia, since they are treated differently. Ventricular tachycardia has to be treated appropriately, since it can quickly degenerate to [[ventricular fibrillation]] and [[death]]. A number of different [[algorithm]]s have been devised to determine whether a wide complex tachycardia is supraventricular or ventricular in origin.<ref>{{cite journal |author=Lau EW, Ng GA |title=Comparison of the performance of three diagnostic algorithms for regular broad complex tachycardia in practical application |journal=Pacing and clinical electrophysiology : PACE |volume=25 |issue=5 |pages=822-7 |year=2002 |pmid=12049375 |doi=}}</ref> | ||
In general, a history of structural heart disease, [[ischemic heart disease]] or [[congestive heart failure]] increases the likelihood that the tachycardia is ventricular in origin. | In general, a history of structural heart disease, [[ischemic heart disease]] or [[congestive heart failure]] increases the likelihood that the tachycardia is ventricular in origin. | ||
==Differentiating SVT from VT== | ==Differentiating SVT from VT== | ||
* | For a detailed discussion of how to distinguish [[ventricular tachycardia]] ([[VT]]) from [[supraventricular tachycardia]] ([[SVT]]), please visit the [[wide complex tachycardia differential diagnosis]] page. | ||
* | |||
* | In brief, the diagnosis of [[VT]] is more likely if: | ||
* | *There is a history of [[myocardial infarction]], [[congestive heart failure]] or [[structural heart disease]] | ||
* | *[[VT]] is more common in the elderly | ||
*The [[electrical axis]] is -90 to -180 degrees (a “northwest” or “superior” axis) | |||
* | *The [[QRS]] is > 140 msec | ||
* | *There is [[AV dissociation]]. [[P waves]] are normal in morphology, upright, but dissociated from the QRS complex (i.e. "march through" the [[QRS complex]]) | ||
*There are positive or negative [[QRS]] complexes in all the precordial leads | |||
*The morphology of the [[QRS]] complexes resembles that of a previous [[premature ventricular contraction]] ([[PVC]]). | |||
*Rate: More than 100 bpm and usually 150-200 bpm | |||
*Rhythm: The rhythm is regular | |||
*[[PR interval]]: Variable PR interval | |||
*Response to Maneuvers: VT does not terminate in response to [[adenosine]] or [[vagal maneuvers]] | |||
==References== | ==References== | ||
Latest revision as of 15:31, 20 August 2013
|
Supraventricular tachycardia Microchapters |
|
Differentiating Among the Different Types of Supraventricular Tachycardia |
|---|
|
Differentiating Supraventricular Tachycardia from Ventricular Tachycardia |
|
Diagnosis |
|
Treatment |
|
2015 ACC/AHA Guideline Recommendations |
|
Case Studies |
|
Supraventricular tachycardia differentiating SVT from VT On the Web |
|
American Roentgen Ray Society Images of Supraventricular tachycardia differentiating SVT from VT |
|
FDA on Supraventricular tachycardia differentiating SVT from VT |
|
CDC on Supraventricular tachycardia differentiating SVT from VT |
|
Supraventricular tachycardia differentiating SVT from VT in the news |
|
Blogs on Supraventricular tachycardia differentiating SVT from VT |
|
Directions to Hospitals Treating Supraventricular tachycardia |
|
Risk calculators and risk factors for Supraventricular tachycardia differentiating SVT from VT |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]
See also: Wide complex tachycardia
Overview
Most supraventricular tachycardias have a narrow QRS complex on the EKG. It is not infrequent, however, for aberrant conduction to be be present, sometimes as a result of the more rapid rate of conduction. This widening of the QRS complex yields supraventricular tachycardia with aberrant conduction (SVTAC) which produces a wide-complex tachycardia that may mimic ventricular tachycardia (VT). In the clinical setting, it is important to determine whether a wide-complex tachycardia is an SVT or a ventricular tachycardia, since they are treated differently. Ventricular tachycardia has to be treated appropriately, since it can quickly degenerate to ventricular fibrillation and death. A number of different algorithms have been devised to determine whether a wide complex tachycardia is supraventricular or ventricular in origin.[1]
In general, a history of structural heart disease, ischemic heart disease or congestive heart failure increases the likelihood that the tachycardia is ventricular in origin.
Differentiating SVT from VT
For a detailed discussion of how to distinguish ventricular tachycardia (VT) from supraventricular tachycardia (SVT), please visit the wide complex tachycardia differential diagnosis page.
In brief, the diagnosis of VT is more likely if:
- There is a history of myocardial infarction, congestive heart failure or structural heart disease
- VT is more common in the elderly
- The electrical axis is -90 to -180 degrees (a “northwest” or “superior” axis)
- The QRS is > 140 msec
- There is AV dissociation. P waves are normal in morphology, upright, but dissociated from the QRS complex (i.e. "march through" the QRS complex)
- There are positive or negative QRS complexes in all the precordial leads
- The morphology of the QRS complexes resembles that of a previous premature ventricular contraction (PVC).
- Rate: More than 100 bpm and usually 150-200 bpm
- Rhythm: The rhythm is regular
- PR interval: Variable PR interval
- Response to Maneuvers: VT does not terminate in response to adenosine or vagal maneuvers