Dr Geraldine Leong goes through some important points in ECG reading and tips for the "not-to-miss" pathologies. Find out more at singem.blogspot.sg

1. ECG: Is it really that simple?ECG: Is it really that simple?
Paramedic Track
SEMS 2014
12th
April 2014
Geraldine Leong, Singhealth Senior Resident

2. Contents
• EMS in SG
• Case Scenarios
– Illustrating mainly STEMIs, SVTs, malignant
bradycardias
• Take home messages

3. EMS in SG
• Single tier, Scoop and Run system
• Mostly intermediate level paramedics
• Each ambulance team consist of:
– SAMO
– Medic
– Paramedic
• Standby system

4. Scenario 1
You’ve just started your ambulance shift at 8 pm… there is a call
for chest pain that just came in from the casino at MBS.

5. Scenario 1

6. Scenario 1
 What do you see in the ECG?
 STANDBY?
 Treatment?
100% NRM?
GTN spray?
Load aspirin 300 mg?
(if no contraindications, as per EAS protocol 12)

7. Scenario 1

8. STEMI
• Definition:
– characteristic symptoms of MI
– Persistent ST elevation
– Subsequent release of biomarkers of myocardial
necrosis

9. How to pick up STEMIs?
• New ST elevations at J point in:
 >/= 2 contiguous leads of >/= 2 mm in men in V2-3
 >/= 2 contiguous leads of >/= 1.5 mm in women in V2-3
 >/= 1 mm in other contiguous chest/limb leads
 Special Cases
 Dx STEMI in the presence of LBBB
 Dx STEMI in the presence of paced rhythm
J point

10. Why is picking up STEMIs important?
• Time = muscle
• Pre-hospital ECGs  shorter reperfusion times 
lower mortality rates from STEMIs1
• Pre-hospital ECGs + comms of STEMI dx + transport to
PCI-capable hospital = rapid reperfusion time +
excellent clinical outcomes2
1. TingHH et al. Circulation. 2008;118:1066-79
2. SorensenJT et al. Eur Heart J. 2011;32:430-6

15. OTHER INTERESTING MI ECGS
Now for more unusual cases…

16. 76 yo/C/F presented with chest pain and diaphoresis

17. 60 yo/I/M presented with chest discomfort,
diaphoresis and breathlessness

18. Scenario 2
You have been called to respond to a 995 call for chest
discomfort at one of the university campus.
BP 140/89 HR 168
SpO2 98% on RA

19. Scenario 2

20. Scenario 2
 What do you see in the ECG?
 STANDBY?
 Treatment?
Supplemental O2?
Vagal Maneuvers? (i.e. valsalva)
(if no contraindications, as per EAS protocol 08)

21. SupraVentricular Tachycardia
• Definition:
– Rapid heart rate (tachycardia >100 bpm)
– Originating at or above the sino-atrial node (ie. above
the bundle branches in the ventricles)

22. Classification
Tachyarrythmias
Narrow-complex Broad-complex
Irregular
- fast atrial
fibrillation
- atrial flutter
with variable
conduction
Regular
- sinus
tachycardia
- SVTs
• Ventricular Fibrillation
• Ventricular Tachycardia

23. How to pick up SVTs?
• 3 main features:
– Regular
– Narrow complex (QRS <120 ms)
– Tachycardic

24. Is this a SVT?
Regular? √
Tachycardia? √
Narrow complex? X

25. Is this a SVT?
Narrow complex? √
Tachycardia? √
Regular? X

26. Regular? √
Narrow complex? √
Tachycardia? √

27. Regular? √
Narrow complex? √
Tachycardia? √

28. Treating the rhythm
STANDBY
High flow O2
IVD
ECG: regular narrow complex tachycardia - SVT
Haemodynamically stable?
Vagal Maneuvers
- Valsalva -
NO Yes

29. What do we do in ED?
• Haemodynamically unstable:
– Sedate and synchronised cardioversion starting at
50J and increasing energy level if unsuccessful
• Haemodynamically stable:
– AV nodal blocking agents
• Adenosine
• Calcium channel blockers
like verapamil or diltiazem

30. Scenario 3
You have reached the home of a 80 year old Chinese gentleman
who called the 995 hotline for syncope.
BP 102/58 HR 44
SPO2 97% on RA

31. Scenario 3

32. Scenario 3
 What do you see in the ECG?
 STANDBY?
 Treatment?
100% NRM?
IV atropine?
(if no contraindications, as per EAS protocol 07)

33. Complete Heart Block
• Definition:
– Also called third degree heart block
– Rhythm when atrial contraction is normal but no
beats are conducted to the ventricle
– Ventricle then are excited by a slow “escape
rhythm” from a depolarising foci within the
ventricle

34. How to pick up CHB?
• ECG features:
– Presence of both P waves and QRS complexes
– No relationship between P waves and QRS
complexes  P waves not conducted
– Sometimes abnormal/broad QRS complexes – due
to abnormal spread of depolarisation from
ventricular focus

35. Scenario 3

36. What should I do for CHB?
STANDBY
High flow O2
IV atropine 0.6 mg q3-5
min (max 2.4 mg)
IVD
ECG: complete heart block
Haemodynamically stable?
Check for signs/sympts of shock (as per EAS protocol 07)
– Transfer to ED ASAP for
further Mx
– Con’t monitoring along
the way for shock
NO Yes

38. Take Home Messages
• Do not fear the ECG!
– Pattern recognition  practice makes perfect
• Always treat the patient!
– Not the ECG.
– STANDBY if high clinical suspicion

39. Thank You!

40. References
• SINGAPORE MYOCARDIAL INFARCTION REGISTRY REPORT NO. 1: TRENDS IN ACUTE
MYOCARDIAL INFARCTION IN SINGAPORE 2007-2010; National Registry of
Diseases Office, MOH
• PT.O’Gara, FG.Kushner et al 2013 ACCF/AHA Guidelines for the Management of
ST-Elevation Myocardial Infarction: A Report of the American College of Cardiology
Foundation/American Heart Association Task Force on Practice Guidelines.
Circulation. Published online Dec 17 2012 Online ISSN 1524-4539
• TingHH et al. Implementation and integration of prehospital ECGs into systems of
care for acute coronary syndrome. Circulation. 2008;118:1066-79
• SorensenJT et al. Urban and rural implementation of pre-hospital diagnosis and direct referral
for primary percutaneous coronary intervention in patients with acute STEMI. Eur Heart J.
2011;32:430-6
• Sarah AS, Robert C. Tachydysrhythmias, Emerg Med Cli N Am 24 (2006) 11-40
• Jacqueline D, Christopher H, Amal M, William J. The electrocardiogram in the
patient with syncope, American Journal of Emergency Medicine (2007) 25, 688–
701

41. Additional Slides (not to be shown)

42. More examples