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■ Stable

■ Trial of amiodarone or lidocaine ORsynchronized cardioversion

■ Refractory stable VT →synchronized cardioversion as above.

TORSADES DEPOINTES

Torsades is a form of polymorphous VT in which the axis of the heart rotates,

creating a sinusoidal appearance of the ventricular rhythm. Definition requires

long QT (>600 msecs) seen on resting ECG or rhythm strip.

CAUSES

■ Prolongation of the QT interval

■ Medications (eg, class IC agents, TCAs)

■ Hypomagesemia

■ Hypokalemia

ECG FINDINGS(SEEFIGURE1.17)

■ Sinusoidal variation in amplitude and duration of wide QRS complexes

■ AV dissociation

RESUSCITATION

TABLE 1.8. Differentiating Ventricular Tachycardia (VT) From SVT With Aberrancy

Historical Clues That Suggest VT

Age> 35 years

History of heart disease

Prior history or family history of VT

General ECG Characteristics That Suggest VT

AV dissociation

Fusion beats

Concordance

Extreme left axis

QRS duration > 0.14 seconds

No response to vagal maneuvers

Brugada ECG Criteria That Suggest VT

Absence of RS complexes in all V leads

If RS complex present →RS duration > 0.1 sec

Presence of AV dissociation

Presence of VT QRS morphology

Torsades is due to

prolongation of repolarization

(QT interval).