In 1976 by Kambara and Phillips suggested that early
repolarization was defined by:
1) end-QRS notching or slurring;
2) elevation of the ST-segment; and
3) an upwardsloping ST-segment followed by a tall,
Haissaguerre et al. defined early repolarization as “an
elevation of the QRS-ST-segment junction (J-point) in at least
2 leads” (within the same territory; e.g., inferior or lateral
leads) as being a sign of early repolarization.
The amplitude of the J-point elevation had to be at least 0.1
mV above the baseline level, as either QRS slurring or
notching. The amplitude and slope of the ST-segment were not
part of the definition
Tikkanen et al. definition also measured the degree of J-point
elevation, which was stratified at levels of 0.1 and 0.2 mV. These
investigators also introduced the concept of the ST-segment slope,
showing that a horizontal or downwardsloping ST-segment is
associated with greater arrhythmic risk
The prevalence of early repolarization in the general
population varies from 1% to 9%, depending on
age (predominant in young adults),
race (highest among black populations),
gender (predominant in men), and
the criterion for J point elevation (0.05 mV versus 0.1 mV)
In a study of a community-based general population of 10,864
middle-aged subjects, the prevalence of early repolarization (J
point elevation >0.1 mV) was
inferior leads- 3.5%,
J point elevation > 0.2 mV,
The ST segment after the J point was
horizontal or descending – 71.5%
rapidly ascending - 28.5%.
incidence - idiopathic VF
age <45 years - 3:100 000.
J-waves- 11:100 000
The presence of ER is associated with 3 times the risk of developing
VF, but the overall risk is still negligible
ER syndrome - syncope or cardiac arrest is attributed
to ER after systematic exclusion of other etiologies.
Another concurrent case–control study also
demonstrated a higher prevalence of ER (42%)
among survivors of idiopathic VF compared with
controls (13%, P<0.01)
ER increases the RR of arrhythmic events, the AR
remains very low.
Incidental identification of ER should not be
interpreted as a high risk marker.
Clinical decisions are driven by the presence and
severity of symptoms and comorbidities
Mechanism of Early
the association of ER with arrhythmic risk is
typically at rest or during sleep,and not during
Prominent phase 1 notch
larger transient-outward K+ current (Ito) -
Greater net repolarizing (outward) current flow
during phase 1.
In ER -enhancement in epi net outward current,
enhancement of the endo-to-epi AP differences
manifests as J-waves
which reflects current flow from depolarized
endo to substantially-repolarized epi - phase 1
Case Report: This young female (14 years) was resuscitated in 2001 following
an episode of sudden death due to VF. All examinations including coronary
angiogram with ergonovine injection, MRI, and flecainide or isoproterenol
infusion were normal. The patient had multiple (>100) recurrences of VF
unresponsive to beta-blockers, lidocaine/mexiletine, verapamil, and amiodarone.
Recurrences of VF were associated with massive accentuation of the early
repolarization pattern at times mimicking acute myocardial ischemia. Coronary
angiography during an episode with 1.2 mV J/ST elevation was normal.
Isoproterenol infusion acutely suppressed electrical storms, while quinidine
eliminated all recurrences of VF and restored a normal ECG over a follow-up of
65 months. Genomic DNA sequencing of KATPchannel genes showed missense
variant in exon 3 (NC_000012) of the KCNJ8 gene, a subunit of the
KATP channel, conferring predisposition to dramatic repolarization changes and
Haissaguerre et al
Ventricular fibrillation with prominent
early repolarization associated with a rare variant of
J Cardiovasc Electrophysiol. 2009;20:93–98.
ER vs Brugada
pause/bradycardia dependent accentuation
dynamic nature - ECG pattern,
suppression of the ECG features and
arrhythmia with isoproterenol and quinidine.
provocation by sodium channel blocker
Some individuals with Brugada syndrome may also
have ER (approximately 12%)
Life-threatening arrhythmias are often the first and unexpected
manifestation of ERsyndrome
Incidental ECG finding – present intermittently.
Repeated measurements from 542 subjects with ER demonstrated the
subsequent absence of ER in≈20%.
Even in the cardiac arrest population, 58% of patients whose
arrest was attributed to ER syndrome had ≥1 ECG that did not
demonstrate the ER pattern during their hospitalization
There is no proven provocative test to identify concealed ER.
Conflicting evidence - association between syncope and ER
Classification – arrythmic risk
associated spatial distribution
Type 1 (ER in the lateral precordial leads) - healthy male athletes and -
Type 2 (ER in the inferior or inferolateral leads) a moderate risk.
Type 3 (ER globally in the inferior,lateral, and right precordial leads) -
Brugada syndrome is classified as type 4 (j-wave/point elevation in
the right precordial leads).
ST characteristics are incremental to the
location with a clear higher risk associated with
the horizontal or down-sloping pattern.
ER pattern on ECG should not lead to classification
of a ER syndrome
other etiologies have been excluded
J-point elevation is augmented immediately preceding
Systematic assessment of survivors of SCD without
evidence of infarction or left ventricular dysfunction.
Diagnosis of Ventricular Fibrillation
from Early Repolarization Syndrome
other etiologies excluded
High risk baseline ER pattern
Increased parasympathetic tone provokes high
risk ER characteristics
Cardiac arrest occurs during sleep/at rest
current guidelines do not recommend
evaluation of coronary
Signal averaged ECG
intravenous epinephrine and
sodium channel blocker
A careful review of
all available ECGs
for evidence of ER is
the time of the
Prognostic Variables of
• Electrocardiographic Markers
• Sex, Family History, and Ethnicity
• Autonomic Tone
greater amplitude of ER
horizontal or down-sloping ST-segment
QRS notching vs slurring
highest risk - ER of high amplitude (≥0.2 mV) in
the inferior limb leads + horizontal or
Horizontal ST-segment after early repolarization
Sex, Family History, and
Bradycardia-dependent augmentation of ER is
observed in both VF cases and healthy controls
Tachycardia tends to normalize ER.
night when parasympathetic tone is augmented
Early Repolarization modifying risk
of underlying Cardiac Pathology
Much more common modifier in the context of structural heart disease
and primary electric disorders
↑ risk of ischemic VF in the event of a myocardial infarction/ischemia
ER - inferior leads -increased risk of life-threatening ventricular
arrhythmias in patients with chronic CAD , after adjustment for LVEF
Predict higher risk of sudden death in nonischemic cardiomyopathy
ER + Brugada pattern
with a ECG is an incremental predictor of arrhythmic events
short QT syndrome .
isoproterenol infusion - acute cases , immediately suppressed
Isoproterenol - initiatedat1.0 μg/min,
targeting a20% increase in heart rate or
an absolute heart rate 90. bpm,
quinidine - chronic cases, decreased recurrent VF suppresses
outward currents - Ito, restored a normal ECG
Adrenergic activation – enhancing inward currents ( L type Ca2+
current) –offset the net outward K+ current excess
is indicated after cardiac arrest.
highly effective in terminating ventricular arrhythmias in
nearly all cases.
no current risk stratification strategy for asymptomatic
Syncope attributed to ER appears clinically uncommon and
warrants an aggressive attempt to verify that syncope is
related to arrhythmia.
Inheritance of Early Repolarization
and Family Screening
heritability in the general population and within families.
Siblings - ↑ unadjusted odds of ER ( odds ratio,2.22 ,P= 0.047)
A study involving 505 Caucasian nuclear families reported that
individuals with ≥1 parent with ER had a 2.5-fold increased
incidence of demonstrating the ER pattern.
Heritability - higher - inferior leads
- notched morphology
AD inheritance pattern with incomplete penetrance
Currently no recommendation to screen the families in individuals
with asymptomatic ER.
The ER syndrome as a primary arrhythmogenic disorder causing
VF is very rare.
lack of clinically useful risk stratifying tools or an established
provocative test for identifying malignant ER, despite some ECG
features that are associated with a higher risk.
As such, patients with asymptomatic ER and no family history of
malignant ER should be reassured that their ECG is a normal
variant, until such time as better tools enable risk stratification.
All patients with ER should continue to have
modifiable cardiac risk factors addressed
As in a war when you don’t know
well your enemy ,it is better to
maintain a constant precaution and
look for as many information as
possible in order to avoid defeat