1. ECG IN STEMI
DR AZERIN OTHMAN
HRPZ II KOTA BHARU
STEMIWORKSHOP
2. • Diagnosis of acute STEMI
• Correlate ECG changes and candidate for reperfusion
therapy
• Assess the success of reperfusion therapy
• Correlate location of MI & extent of myocardial
injury - stratification/prognostication/complications
- optimal treatment
ROLES OF ECG IN STEMI
4. CLINICAL DIAGNOSIS OF ACUTE STEMI
1.Chest pain or equivalent symptoms or events suggestive ischaemic in origin.
+
2.ECG changes : Any of the followings (on its own or in any combinations):
ST elevation in 2 or more contiguous leads of standard 12 lead ECG as
follows:
Posterior Infarction
RV Infarction
New onset LBBB
+
3.Elevated cardiac markers
4
- ≥ 1mm limb leads : I, aVL, II, III, aVF.
- ≥ 1mm precordial leads : V4 - V6.
- ≥ 2 mm precordial leads : V1 - V3 .
6. ECG CHANGES IN STEMI
1.HYPERACUTE PEAK T WAVE - HYPERACUTE T WAVE
- T waves tall, symmetrical & peaked
- usually present 5- 30 minutes after the onset of MI later followed by ST
changes.
7. ECG CHANGES IN STEMI
2.ST SEGMENT ELEVATION - HYPERACUTE ST ELEVATION
- commonly seen
- usually within hours after onset of MI
- occurs in the leads facing the infarction
8. ECG CHANGES IN STEMI
3. PATHOLOGICAL Q WAVE - FULLY EVOLVED PHASE
- at least 0.04 seconds in duration
- depth of more than 25% of ensuing R wave
- usually after 9 hours, occasionally after 24 hours after onset of MI
- evidence of myocardial necrosis
- loss of R wave after 12 hours
9. ECG CHANGES IN STEMI
4.RESOLUTION OF ST ELEVATION & T WAVE INVERSION - RESOLUTION PHASE
- ST segment elevation diminishes and T wave inverted.
- occurs around 1 week
10. ECG CHANGES IN STEMI
5.RESOLUTION OF ST ELEVATION & T WAVE INVERSION - CHRONIC PHASE
- persistent Q wave or reduced /poor R wave
- T wave normalised.
- occurs after months-years
13. ST ELEVATION IN ACUTE STEMI
ST elevation in 2 or more contiguous leads of
standard 12 lead ECG as follows:
- ≥ 1mm limb leads : I, aVL, II, III, aVF.
- ≥ 1mm precordial leads : V4 - V6.
- ≥ 2 mm precordial leads : V1 - V3 .
14. Inferior STEMI
• ST elevation: II,III,aVF
• Reciprocal ST depression :
I,aVL
• Infarct artery: RCA (80%)
LCX (20%)
15. Anteroseptal STEMI
• ST elevation: V1-V4
• Can have reciprocal ST
depression inferior leads
• Infarct artery : LAD
16. Extensive Anterior STEMI
• ST elevation: I,aVL,
V1-V6.
• Can have reciprocal ST
depression inferior leads
• Infarct artery : LAD
17. Anterior STEMI
• ST elevation: V1-V6.
• Can have reciprocal ST
depression inferior leads
• Infarct artery : LAD
18. Lateral STEMI
• ST elevation: I,aVL ,
V5-V6.
• Can have reciprocal ST
depression inferior leads
• Infarct artery : LCX
19. Posterior infarction
• Usually associated with inferior and/or lateral
and or RV STEMI
• 4% occur alone - called true/isolated posterior
STEMI
• ECG of posterior infarction are :
ST depression ≥ 1mm (0.1mv) with upright T wave precordial leads : V1 - V4
and / or
ST elevation ≥ 1mm (0.1mv) in the posterior leads : V7 - V9
and / or
Tall R wave and duration ≥ 0.04s precordial leads : V1 or V2
and / or
The ratio of the R / S wave > 1 precordial leads : V1 or V2
*Some use ST elevation ≥ 0.5mm in V7-V9 for diagnosis of posterior MI
20. True posterior STEMI
ST depression ≥ 1mm (0.1mv) with uprightT wave precordial leads :
V1 –V3
21. If we flip or view ECG
posteriorly
ST depression ≥ 1mm (0.1mv) with uprightT wave precordial leads :
V1 –V3 ST elevation when view ECG posteriorly
22.
23. ST depression ≥ 1mm (0.1mv) in leads : V1-V3 ST elevation ≥ 1mm (0.1mv) in leads : V7-V9
24. Other posterior leads placement….
LEADV1 → LEAD V7
LEAD V2 → LEAD V8
LEAD V3 → LEAD V9
25. ECG-POSTERIOR STEMI
Tall R wave and duration ≥ 0.04s
precordial leads : V1 or V2
The ratio of the R / S wave > 1
precordial leads : V1 or V2
Flip back
OTHER CAUSES OFTALL R -V1-V2
26. TRUE POSTERIOR INFARCTION
• ST depression + upright T: V1-V4
and/or
• ST elevation : V7-V9
and/or
• Tall R wave and duration ≥ 0.04s
precordial leads : V1 or V2
and /or
• The ratio of the R / S wave > 1
precordial leads : V1 or V2
• Infarct artery : LCX
POSTERIOR LEADS
27. Infero - lateral - posterior STEMI
• ST elevation : II,III,aVF
V4-V6
• ST depression: V1-V3
• Infarct artery : RCA
ST depression ≥ 1mm (0.1mv)
with uprightT wave precordial leads :
V1 –V2
28. RV INFARCTION
• Usually with inferior STEMI & ST elevation is
transient, disappearing in less than 10 hours
following its onset in half of patients.
• Do right sided ECG in all inferior STEMI
• ECG of RV infarction is
30. • ST elevation : RV3 ,RV4
• Usually asstd : inferior
STEMI
• Infarct artery : RCA
31. LBBB AND STEMI
• New onset LBBB - as STEMI presentation
• STEMI AS LBBB - higher hospital mortality
• Guidelines new LBBB STEMI reperfusion RX
• Beside STEMI many other causes of LBBB
• LBBB obscure classical STEMI ECG-Q wave & ST-T changes
• How do we predict the likelihood of LBBB as true STEMI
( the best & goal standard is coronary angiogram !!)
BUT…. PCI NOT READILY AVAILABLE
EVERYWHERE & WITHIN TIME
?? ENSURE GIVE FIBRINOLYSIS
TO “TRUE “ STEMI…
32. LBBB IN STEMI
LBBB can be associated with
STEMI in the following ways
• True STEMI - with massive
myocardial damage
• Preexisting LBBB with acute
STEMI
• Transient ischemic LBBB during
STEMI
• Rate dependent LBBB (Usually
tachycardia related )
• STEMI in pacemaker rhythms
CAUSES OF LBBB
- STEMI
- HYPERTENSION
- AORTIC VALVE DISEASE
- EXTENSIVE CAD
- DEGENERATIVE DISEASE
- CONGENITAL HEART
DISEASE
- PACEMAKER RHYTHM
34. SGARBOSSA CRITERIA
CRITERIA 1:
ST ELEVATION > 1MM IN ANY CONCORDANT
LEAD ( POSITIVEQRS)
SCORE : 5 - MOST PREDICTIVE
CRITERIA 2:
ST DEPRESSION > 1MM IN ANY LEAD V1-V3
SCORE : 3
CRITERIA 3:
ST ELEVATION > 5MM IN ANY DISCORDANT
LEAD ( NEGATIVE QRS)
SCORE : 2 - LEAST PREDICTIVE
SCORE ≥ 3 : 90% SPECIFIC FOR STEMI & CUTPOINT USED
35. LBBB + INFERIOR STEMI
LBBB + ST > 1mm in lead with a positiveQRS complex ( lead II) → score 5
likely STEMI as score ≥ 3
36. LBBB + ANTERIOR MI
LBBB + ST elevation > 1mm in leads with positive QRS complex ( V4-V5)→ score 5
likely STEMI as score ≥ 3
37. LBBB
LBBB + ST elevation > 5mm in leads with negative QRS complex (V1-V3) → score 2
unlikely STEMI as score < 3
39. CLINICAL ASSESSMENTOF SUCCESSFUL
REPERFUSION
RESOLUTION OF CHEST PAIN
ABSOLUTE RESOLUTION OF ST ELEVATION OR
REDUCTION OF ≥ 50% OF ST ELEVATION
EARLY PEAK CARDIAC ENZYME
IDIOVENTRICULAR RHYTHM
TWAVE INVERSION WITHIN 4 HOURS
40. PRE REPERFUSION RX POST REPERFUSION RX-90 MIN
CLINICAL ASSESSMENT OF SUCCESSFUL
REPERFUSION
