Short QT syndrome differential diagnosis: Difference between revisions
(Created page with "__NOTOC__ {{Short QT syndrome}} {{CMG}} ==Overview== In contrast to Long QT Syndrome (LQTS), there is often no specific trigger (such as a loud noise or exercise) for...") |
No edit summary |
||
(9 intermediate revisions by 2 users not shown) | |||
Line 1: | Line 1: | ||
__NOTOC__ | __NOTOC__ | ||
'''To go back to the main page, click [[Short QT syndrome|here]].''' | |||
{{Short QT syndrome}} | {{Short QT syndrome}} | ||
{{CMG}} | {{CMG}}{{sumanthK}} | ||
==Overview== | ==Overview== | ||
In contrast to [[Long QT Syndrome]] ([[LQTS]]), there is often no specific trigger (such as a loud noise or exercise) for an episode of [[arrhythmia]]. | In contrast to [[Long QT Syndrome]] ([[LQTS]]), there is often no specific trigger (such as a loud noise or exercise) for an episode of [[arrhythmia]]. Short QT syndrome must be differentiated from the normal variant, secondary causes of QT prolongation, and deceleration dependent shortening of QT interval. | ||
<br /> | |||
==Differentiating SQTS from other Diseases== | |||
[[Short QT syndrome]] must be differentiated from [[normal variant]], [[secondary causes of QT prolongation]], and [[deceleration dependent shortening of QT interval]]. | |||
* Normal variant: The presence of shorter QT interval does not automatically qualify for a diagnosis of SQTS. It may also represent a normal variant in the general population. Up to 2 % population has QT interval of ≤ 360 msec. This highlights the importance of using the diagnostic criteria for a final diagnosis of SQTS. | |||
* Acquired causes of SQT interval: Conditions like hyperkalemia, acidosis, hyperthermia, hypercalcemia, digitalis, Acetylcholine, and catecholamines are a few causes of SQT interval. For more acquired causes click [[Short QT syndrome causes|here]]. | |||
* Deceleration dependent shortening of QT interval: This is a paradoxical ECG phenomenon termed as a deceleration-dependent shortening of QT interval. A strong parasympathetic stimulation not only leads to bradycardia but also leads to the activation of acetylcholine-sensitive K+ channels (KACh).In this case, the QT interval shortens paradoxically with bradycardia instead of prolongation. This change is a transient one and shall revert when the parasympathetic stimulus is decreased<ref name="pmid10068851">{{cite journal| author=Gussak I, Liebl N, Nouri S, Bjerregaard P, Zimmerman F, Chaitman BR| title=Deceleration-dependent shortening of the QT interval: a new electrocardiographic phenomenon? | journal=Clin Cardiol | year= 1999 | volume= 22 | issue= 2 | pages= 124-6 | pmid=10068851 | doi=10.1002/clc.4960220213 | pmc=6655337 | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=10068851 }} </ref>. | |||
==References== | ==References== | ||
{{Reflist|2}} | {{Reflist|2}} |
Latest revision as of 03:30, 23 June 2020
To go back to the main page, click here.
Short QT syndrome Microchapters |
Diagnosis |
---|
Case Studies |
Short QT syndrome differential diagnosis On the Web |
American Roentgen Ray Society Images of Short QT syndrome differential diagnosis |
Risk calculators and risk factors for Short QT syndrome differential diagnosis |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]Sumanth Khadke, MD[2]
Overview
In contrast to Long QT Syndrome (LQTS), there is often no specific trigger (such as a loud noise or exercise) for an episode of arrhythmia. Short QT syndrome must be differentiated from the normal variant, secondary causes of QT prolongation, and deceleration dependent shortening of QT interval.
Differentiating SQTS from other Diseases
Short QT syndrome must be differentiated from normal variant, secondary causes of QT prolongation, and deceleration dependent shortening of QT interval.
- Normal variant: The presence of shorter QT interval does not automatically qualify for a diagnosis of SQTS. It may also represent a normal variant in the general population. Up to 2 % population has QT interval of ≤ 360 msec. This highlights the importance of using the diagnostic criteria for a final diagnosis of SQTS.
- Acquired causes of SQT interval: Conditions like hyperkalemia, acidosis, hyperthermia, hypercalcemia, digitalis, Acetylcholine, and catecholamines are a few causes of SQT interval. For more acquired causes click here.
- Deceleration dependent shortening of QT interval: This is a paradoxical ECG phenomenon termed as a deceleration-dependent shortening of QT interval. A strong parasympathetic stimulation not only leads to bradycardia but also leads to the activation of acetylcholine-sensitive K+ channels (KACh).In this case, the QT interval shortens paradoxically with bradycardia instead of prolongation. This change is a transient one and shall revert when the parasympathetic stimulus is decreased[1].
References
- ↑ Gussak I, Liebl N, Nouri S, Bjerregaard P, Zimmerman F, Chaitman BR (1999). "Deceleration-dependent shortening of the QT interval: a new electrocardiographic phenomenon?". Clin Cardiol. 22 (2): 124–6. doi:10.1002/clc.4960220213. PMC 6655337 Check
|pmc=
value (help). PMID 10068851.