How can you distinguish between ventricular tachycardia and supraventricular tachycardia?

There are two situations in which it may be difficult to differentiate supraventricular tachycardia from ventricular tachycardia via the surface 12 lead electrocardiogram: (1) when supraventricular tachycardia is conducted to the ventricles with aberration, and (2) when ventricular preexcitation is present.

How do you interpret ventricular tachycardia?

If the QRS complex in V1–V2 resembles a left bundle branch block (i.e negative QRS)

1. The initial portion of the QRS complex is smooth in ventricular tachycardia.
2. R-wave duration ≥40 ms suggest ventricular tachycardia.
3. Duration from start of QRS complex to nadir of S-wave ≥60 ms suggests ventricular tachycardia.

How many beats of VT is significant?

VT is defined as 3 or more heartbeats in a row, at a rate of more than 100 beats a minute. If VT lasts for more than a few seconds at a time, it can become life-threatening. Sustained VT is when the arrhythmia lasts for more than 30 seconds, otherwise the VT is called nonsustained.

Are P waves present in ventricular tachycardia?

TREATMENT OF VENTRICULAR TACHYCARDIA. VT is recognized by abnormally wide and bizarre QRS complex morphology. P waves are present but may be hiding in the QRS-T complexes. AV dissociation occurs due to the accelerated ventricular rate as compared to the sinus rate.

What is discordant ST elevation?

ST-elevation is “excessively discordant” when the ST-elevation (measured at the J-point) is > 0.25 or 25% the depth of the S-wave. ST-depression is “excessively discordant” when the ST-depression (measured at the J-point) is > 0.3 or 30% the height of the R-wave.

What distinction do ventricular rhythms share?

The inherent rate of a ventricular rhythm is very slow, between 20-40 beats per minute. The defining characteristics of ventricular rhythms are the lack of P waves and the wide QRS complexes. The QRS complex will be over 0.12 seconds in duration (over three small boxes wide).

What is AV and VA concordance?

Atrioventricular (AV) discordance with ventriculoarterial (VA) concordance is a rare form of congenital heart disease that consists of 5 different anatomic types.

What does AV and VA concordance mean?

there is atrioventricular (AV) discordance and ventricular- arterial (VA) concordance (AVD-VAC). 1 Thus although the aorta arises from the left ventricle and the pulmonary artery (PA) originates from the right ventricle, the systemic and pulmo- nary circulations are in parallel and not in series.

Is VT a shockable rhythm?

VF and pulseless VT are both shockable rhythms.

Why does ventricular tachycardia have wide QRS?

During VT, the width of the QRS complex is influenced by: The site of VT origin: free wall sites of origin result in wider QRS complexes due to sequential activation (in series) of the two ventricles, as compared to septal sites, which result in simultaneous activation (in parallel).