Tachycardia: Difference between revisions

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==Differentiation between SVT and VT==
==Differentiation between SVT and VT==
To differentiate between supraventricular tachycardias and ventricular tachycardias a 12 lead ECG is the cornerstone of the diagnostic process. At first, the physician has to make a differentiation between a small or broad complex tachycardia.  
To differentiate between supraventricular tachycardias and ventricular tachycardias a 12 lead ECG is the cornerstone of the diagnostic process. At first, the physician has to make a differentiation between a narrow or wide complex tachycardia.  


===Definitions===
===Definitions===
*'''Narrow complex tachycardia:''' QRS duration < 120 ms.
 
'''Narrow complex tachycardia:''' QRS duration < 120 ms.  
A narrow complex tachycardia is most likely to be a SVT. However, also a septal VT or His-tachycardia can appear as a narrow complex tachycardia.  
A narrow complex tachycardia is most likely to be a SVT. However, also a septal VT or His-tachycardia can appear as a narrow complex tachycardia.  


*'''Wide complex tachycardia:''' QRS duration > 120 ms.
'''Wide complex tachycardia:''' QRS duration > 120 ms.
A wide complex tachycardia can be due to a SVT with aberration, pre-exited tachycardia (eg antidrome re-entry tachycardia) or VT.  
A wide complex tachycardia can be due to a SVT with aberration, pre-exited tachycardia (eg antidrome re-entry tachycardia) or VT.  


===Differentiation===
===Differentiation===
These are the flow charts of a small and wide complex tachycardia to differentiate between the different rhythms:
These are the flow charts of a small and wide complex tachycardia to differentiate between the different rhythms:


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===Treatment===
===Treatment===
'''Haemodynamical instable (systolic blood pressure less than 100 mmHg):'''
'''Haemodynamical instability (systolic blood pressure less than 100 mmHg):'''  
*Electrical cardioversion (with anesthesia when concious)
*electrical cardioversion  


'''Haemodynamically stable regular narrow complex tachycardia:'''
'''Haemodynamical stability in a regular small complex tachycardia:'''  
*Carotid massage (after palpation and ausculatation of carotid arteries for exclusion of carotid occlusion/stenosis)  
*Carotid massage (after palpation and ausculatation of carotid arteries for exclusion of carotid occlusion/stenosis)  
*Vasalva manoeuvre  
*Vasalva manoeuvre