Tachycardia: Difference between revisions

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=Ventricular tachycardia=
=Ventricular tachycardia=
Ventricular tachycardias are rhythm disturbances that arise in the ventricles.
Ventricular tachycardias (VT's) are rhythm disturbances that arise in the ventricles.
 
===History===
Symptoms can arise in every ventricular tachycardia, depending on the heart rate, the presence of underlying heart disease and the degree of systolic heart failure. Various symptoms are:
* Palpitations
* Abnormal chest sensation
* Angina
* Presyncope (lightheadedness, weakness, diaphoresis)
* Syncope
* Cardiogenic shock
 
Additional information about drug is mandatory. Toxic levels of digoxin and cocain can lead to VT's.
 
===Physical Examination===
Although the diagnosis of VT is generally made by a 12 lead ECG, the following physical symptoms may be present:
* Cannon "A" waves on the jugular venous pulse in the neck. These represent intermittant retrograde propulsion of blood into the jugular veins during right atrial contraction against a closed AV valve. This is evidence of AV dissociation.
* Decreased or variable amplitude of the carotid or peripheral pulses. This is related to the intermittent periods of atrial and ventricular synchronization, which transiently augment cardiac output.
* Variable intensity of the first heart sound (although this is difficult with a rapid heart rate).
* Variable splitting of the first and second heart sounds, and intermittent presence of a third and/or fourth heart sound.
 


==Ventricular tachycardia==
==Ventricular tachycardia==
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