Approach to Myocardial Infarction

1. Approach to Myocardial
Infarction
Dr. Sruthi Meenaxshi
(PDF) VMCRH

2. Definition
• According to the American College of Cardiology/American Heart
Association guidelines for STEMI, there must be “new ST segment
elevation at the J point in at least two contiguous leads of ≥ 2 mm (0.2
mV) in men or 1.5 mm (0.15 mV) in women in leads V2-V3 and/or of
≥ 1 mm (0.1 mV) in other contiguous chest leads or the limb leads.”
This means 1 millimeter in any two contiguous leads, except leads V2
or V3, where the elevation must be 2 mm in men or 1.5 mm in
women.

4. New concepts

10. Type 1 Myocardial infarction

11. Type 2 Myocardial infarction due to oxygen
supply demand mismatch

13. Type 2 MI due to oxygen supply and demand
imbalance

14. Type 3 sudden cardiac death due to MI when
cardiac biomarkers are unavailable

15. Type 4a (PCI related MI)

16. Type 4b MI due to stent thrombosis

17. Type 5 MI ( CABG related])

18. CORONARY ANATOMY

21. ST ELEVATION MI(STEMI)

22. Anterior wall MI

24. DE WINTER “T” WAVES

25. A 55year old male presented to ED with acute
onset chest pain ,diaphoresis and palpitation .
Trop T and I was elevated .What is the probable
diagnosis ?Comment on ECG and Culprit vessel?

26. LMCA Occlusion
• Typical ECG findings with LMCA occlusion:
• Widespread horizontal ST depression, most prominent in leads I, II and V4-
6
• ST elevation in aVR ≥ 1mm
• ST elevation in aVR ≥ V1
• ST Elevation in aVR may also be seen with:
• Proximal left anterior descending artery (LAD) occlusion
• Severe triple-vessel disease (3VD)
• Diffuse subendocardial ischaemia – e.g. due to O2 supply/demand
mismatch, following resuscitation from cardiac arrest

27. A 45year old came to ED with acute onset
chest pain .Diagnosis?

28. LAD OCCLUSION PROXIMAL TO SEPTAL

29. High lateral MI

30. South African Flag sign

31. What is your diagnosis?

32. Inferior wall MI

33. A 56 year old male presented to ED is acute onset
chest pain ,cardiac biomarkers are elevated.What
is your diagnosis?

34. 50 year old presented with acute onset chestpain
,breathelessness ,Ecg shows as below .what is
your diagnosis?

35. A 55 yearold man presented to ED with acute
onset chest pain,palpitation and breathelessness .
What is your diagnosis?

36. Comment on Ecg and tell your diagnosis?

38. Right ventricular infarction
In patients presenting with inferior STEMI, right ventricular
infarction is suggested by the presence of:
•ST elevation in V1 – the only standard ECG lead that looks
directly at the right ventricle.
•ST elevation in lead III > lead II – because lead III is more
“rightward facing” than lead II and hence more sensitive to the
injury current produced by the right ventricle.
Right ventricular infarction is confirmed by the presence of
ST elevation in the right-sided leads (V3R-V6R).

39. A 44 year old female presented with the following
ecg finding ,no chestpain with minimal increase
cardiac biomarker ? What is your diagnosis ?

41. Wellens Pattern? What is it? Why is it
significant?

42. Comment on the Ecg and give a probable
Diagnosis?

43. Posterior wall MI
• Posterior MI is suggested by the following changes in V1-3:
• Horizontal ST depression
• Tall, broad R waves (>30ms)
• Upright T waves
• Dominant R wave (R/S ratio > 1) in V2

44. LV aneurysm
• A LV aneurysm can be diagnosed on ECG when there is persistent ST
segment elevation occurring 6 weeks after a known transmural MI (usually
anterior).
• Without knowing the persons past medical history, the ECG changes of an
aneurysm may mimic an acute ST segment elevation MI. With an anterior
or apical aneurysm, the persistent ST elevation is in lead V1 and V2. In an
inferior aneurysm it would be in lead II, III and aVF.
• The only way to be sure of an LV aneurysm diagnosis on an ECG (not from
an acute MI) is to have the patient’s history of a prior heart attack and
cardiac imaging to document the presence of an aneurysm.
• The shape of the ST elevation is also relatively unique and has been
described as “coving”.

45. LV aneurysm

46. Thankyou