Syncope ECG

1. ACS

2. Wolff-Parkinson-White syndrome (WPW): the most common form
of preexcitation, WPW is associated with the classic triad of
short PR interval, QRS complex widening greater than 100 milli-
seconds, and the delta wave (slurred upstroke of the QRS com-
plex). It is important to remember that delta waves, although the
most well known of the triad, are often absent in many leads.
The short PR interval is actually the most consistent finding in
all of the leads.

3. Brugada syndrome: Brugada syndrome is a purely electrical
phenomenon (meaning that patients have structurally normal hearts)
that is associated with unpredictable episodes of ventricular
tachycardia. Patients may have sudden death, but if the arrhythmia
terminates spontaneously, the patient presents instead with syncope.
The resting ECG demonstrates a right bundle branch block
morphology with STE in leads V1 to V2.

4. Hypertrophic cardiomyopathy (HCM): hypertrophic cardiomyopa-
thy may be associated with episodes of ventricular tachyarrhyth-
mias, usually associated with exertion, in relatively young patients.
The ECG manifestations of HCM are often nonspecific (high
voltage in the precordial leads, left atrial enlargement, tall R waves
in right precordial leads, and abnormal Q waves in the inferior and/
or lateral leads) [32]. However, the combination of high voltage
with deep, narrow Q waves in the inferior and/or lateral leads is
highly specific for this entity.

5. Prolongation of the QT interval: patients with a prolonged QTc
interval are at risk for torsades de pointes. Patients are at highest risk
when the QTc interval is greater than 500 milliseconds. Major causes
of prolonged QTc interval include hypokalemia, hypocalcemia,
hypomagnesemia, hypothermia, elevated intracranial pressure, acute
cardiac ischemia, sodium channel blocking drugs, and hereditary long
QT syndrome.

Dovgalyuk Am J Emerg Med. 2007 Jul;25(6):688-701


Michelle Lin Brugada Syndrome Card: