1 Reason Ischemic heart disease causes the greatest number of - - PDF document

1

Slide 1 JSOMTC, SWMG(A)

12 Lead Electrocardiogram (ECG) PFN: SOMACL17

Slide 2

JSOMTC, SWMG(A)

Terminal Learning Objective

 Action: Communicate knowledge of 12

Lead Electrocardiogram (ECG)

 Condition: Given a lecture in a classroom

environment

 Standard: Received a minimum score of

84% on the written exam IAW course AHA standards

Slide 3

JSOMTC, SWMG(A)

References

 Advanced Cardiovascular Life Support,

Provider Manual 2010

 The 12 lead ECG in Acute Myocardial

Infarction 1996

 The 12 lead ECG for Acute and Critical Care

Providers 2005

2

Slide 4

JSOMTC, SWMG(A)

Reason

 Ischemic heart disease causes the greatest

number of deaths in the United States.

 50% die before arriving at a hospital.  If treatment is not received within 2 hours

• f onset of symptoms, chance of survival is

25%.

 By treating a heart attack within one hour

• f onset of symptoms, the chance of

survival is 49%!

Slide 5

JSOMTC, SWMG(A)

Reason

 The keys to quick management of an acute

myocardial infarction (AMI) patient are:

• Prompt recognition of the symptoms
• Rapid performance and interpretation of a 12

Lead ECG

• Provide pre‐arrival notification to the receiving

facility

Slide 6

JSOMTC, SWMG(A)

Agenda

 Recall the pathophysiology of acute

myocardial infarction (AMI)

 Identify the electrode placement for a 12

Lead ECG

 Identify the 12 Lead ECG physiology to

assess an AMI

 Identify an AMI using a 12 Lead ECG

3

Slide 7

JSOMTC, SWMG(A)

Agenda

 Identify the limitations and complications

• f recognizing an AMI using a 12 Lead ECG

 Participate in a 12 Lead ECG interpretation

practical exercise

Slide 8 JSOMTC, SWMG(A)

Pathophysiology of Acute Myocardial Infarction (AMI)

Slide 9

JSOMTC, SWMG(A)

Pathophysiology of AMI

 A heart attack occurs when

a thrombus or blood clot forms in a coronary artery, cutting off the blood supply to a segment of the heart muscle.

 Prompt restoration of

blood flow can stop and minimize (or even prevent) the heart damage.

4

Slide 10

JSOMTC, SWMG(A)

Pathophysiology of AMI

 The blood flow can be restored by:

• Percutaneous coronary intervention (PCI)
• Coronary artery bypass graft (CABG)
• Administration of a clot dissolving

(thrombolytic) drug

Slide 11

JSOMTC, SWMG(A)

Pathophysiology of AMI

 ACS symptom review:

• Crushing chest pain lasting more than 15

minutes

• Chest Pain spreading to the shoulders, neck,

arms or jaw

• Chest discomfort with lightheadedness,

fainting, sweating or nausea

• Shortness of breath with or without chest

discomfort

Slide 12 JSOMTC, SWMG(A)

Electrode Placement for a 12 Lead ECG

5

Slide 13

JSOMTC, SWMG(A)

ECG Leads

 Bipolar

• Leads I, II, and III

 Unipolar

• Leads aVR, aVL, and aVF

 Precordial

• V1, V2, V3, V4, V5, and V6

Slide 14

JSOMTC, SWMG(A)

12 Lead ECG Preparation

Slide 15

JSOMTC, SWMG(A)

Bipolar and Unipolar Leads

6

Slide 16

JSOMTC, SWMG(A)

Precordial Leads

Slide 17

JSOMTC, SWMG(A)

V1

Slide 18

JSOMTC, SWMG(A)

V2

7

Slide 19

JSOMTC, SWMG(A)

V4

Slide 20

JSOMTC, SWMG(A)

V3

Slide 21

JSOMTC, SWMG(A)

V5

8

Slide 22

JSOMTC, SWMG(A)

V6

Slide 23

JSOMTC, SWMG(A)

12 Lead ECG Electrode Placement

Slide 24 JSOMTC, SWMG(A)

12 Lead ECG Physiology to Assess an AMI

9

Slide 25

JSOMTC, SWMG(A)

12 Lead ECG Relationship to Coronary Artery Anatomy

 Let’s look at the heart

• Page 28 in the ACLS Handbook
• The right coronary artery (RCA) supplies
• xygen to the inferior (bottom) surface of the

heart

Slide 26

JSOMTC, SWMG(A)

12 Lead ECG Relationship to Coronary Artery Anatomy

 The left coronary artery (LCA) splits in two:

• The left anterior descending coronary artery

(LAD)

• The left circumflex coronary artery (LCX or Cx)

Slide 27

JSOMTC, SWMG(A)

12 Lead ECG Relationship to Coronary Artery Anatomy (cont)

10

Slide 28

JSOMTC, SWMG(A)

12 Lead ECG Relationship to Coronary Artery Anatomy

 The left anterior descending coronary

artery (LAD) courses down the anterior (front) surface of the heart and supplies

• xygen to the septal, anterior, and lateral

sides of the heart.

Slide 29

JSOMTC, SWMG(A)

12 Lead ECG Relationship to Coronary Artery Anatomy (cont)

Slide 30

JSOMTC, SWMG(A)

12 Lead ECG Relationship to Coronary Artery Anatomy

 The left circumflex coronary artery (Cx)

supplies oxygen to the left lateral (side) surface of the heart.

11

Slide 31

JSOMTC, SWMG(A)

12 Lead ECG Relationship to Coronary Artery Anatomy (cont)

Slide 32

JSOMTC, SWMG(A)

12 Lead ECG Relationship to Coronary Artery Anatomy

Slide 33

JSOMTC, SWMG(A)

12 Lead ECG Relationship to Coronary Artery Anatomy (cont)

aVF inferior III inferior V3 anterior V6 lateral aVL lateral II inferior V2 septal V5 lateral aVR I lateral V1 septal V4 anterior

12

Slide 34

JSOMTC, SWMG(A)

12 Lead ECG Relationship to Coronary Artery Anatomy

Slide 35 JSOMTC, SWMG(A)

Identify an AMI Using a 12 Lead ECG

Slide 36

JSOMTC, SWMG(A)

Analyze the 12 Lead ECG

13

Slide 37

JSOMTC, SWMG(A)

Normal 12 Lead ECG

Slide 38

JSOMTC, SWMG(A)

12 Lead Versus 3 Lead ECG

 Differences

• 2.5 second views instead of a 6 second view
• Legend
• Views mimic anatomy of the heart

Slide 39

JSOMTC, SWMG(A)

Identify an AMI

Baseline Ischemia—tall or inverted T wave (infarct), ST segment may be depressed (angina) Injury—elevated ST segment, T wave may invert Infarction (Acute)—abnormal Q wave, ST segment may be elevated and T wave may be inverted Infarction (Age Unknown)—abnormal Q wave, ST segment and T wave returned to normal

14

Slide 40

JSOMTC, SWMG(A)

ECG Recording

Slide 41

JSOMTC, SWMG(A)

Identify an AMI

 Know what to look for:

• Measure from J point
• ST elevation or

depression >1 mm

• 2 anatomical leads
• Pathologic Q wave

greater than 40 ms or greater than 1/3 height

• f R wave

PR baseline ST‐segment deviation = 4.5 mm J point plus 0.04 second

Slide 42

JSOMTC, SWMG(A)

ST Segment Elevation Myocardial Infarctions (STEMIs)

 Acute Anterior Wall Infarct  Anterolateral Infarct  Acute Inferior Wall Infarct

15

Slide 43

JSOMTC, SWMG(A)

Acute Anterior Wall Infarct

Slide 44

JSOMTC, SWMG(A)

Anterolateral Infarct

Slide 45

JSOMTC, SWMG(A)

Acute Inferior Wall Infarct

16

Slide 46 JSOMTC, SWMG(A)

Limitations and Complications of Recognizing an AMI Using a 12 Lead ECG

Slide 47

JSOMTC, SWMG(A)

Limitations of 12 Lead ECG

 12 Lead ECG:

• Does not look at the right ventricle of the heart
• Acute Right Ventricular Infarct
• Does not look at the posterior (rear) of the heart
• Posterior Wall Infarct

 Patient can still be having an AMI even if ST

elevation is not seen on a 12 lead ECG

Slide 48

JSOMTC, SWMG(A)

Right Ventricular Infarct

17

Slide 49

JSOMTC, SWMG(A)

Right Ventricular Infarct

 Looks just like an inferior infarct  Take lead V4 and place it 5th ICS MCL on

the right side of the chest

 RVI suspected if ST elevation is present in

that lead

 Usually this patient is in cardiogenic shock

due to a heavy reliance on preload

 Don’t administer Nitro or Morphine

Slide 50

JSOMTC, SWMG(A)

Posterior Wall Infarct

Slide 51

JSOMTC, SWMG(A)

Posterior Wall Infarct

 ST segment depression is reciprocal of ST

segment elevation

 Taller R wave is reciprocal of pathological Q

wave

 Usually noticed in leads V1, V2, and V3

18

Slide 52

JSOMTC, SWMG(A)

Complications of 12 Lead ECG

 AMI can affect the conduction system of

the heart

• New Left Bundle Branch Block

 Lethal Dysrhythmias

• Examples: VF or Pulseless VT

 Cardiogenic Shock

Slide 53

JSOMTC, SWMG(A)

Left Bundle Branch Block

Slide 54

JSOMTC, SWMG(A)

Left Bundle Branch Block

19

Slide 55

JSOMTC, SWMG(A)

Left Bundle Branch Block

 Look at the QS complex in V1  QRS > 0.12 seconds  Pointing down indicates LBBB

Slide 56 JSOMTC, SWMG(A)

12 Lead ECG Interpretation Practical Exercise

Slide 57

JSOMTC, SWMG(A)

Practical Exercise

20

Slide 58 JSOMTC, SWMG(A)

Questions?

Slide 59

JSOMTC, SWMG(A)

Terminal Learning Objective

 Action: Communicate knowledge of 12

Lead Electrocardiogram (ECG)

 Condition: Given a lecture in a classroom

environment

 Standard: Received a minimum score of

84% on the written exam IAW course AHA standards

Slide 60

JSOMTC, SWMG(A)

Agenda

 Recall the pathophysiology of acute

myocardial infarction (AMI)

 Identify the electrode placement for a 12

Lead ECG

 Identify the 12 Lead ECG physiology to

assess an AMI

 Identify an AMI using a 12 Lead ECG

21

Slide 61

JSOMTC, SWMG(A)

Agenda

 Identify the limitations and complications

• f recognizing an AMI using a 12 Lead ECG

 Participate in a 12 Lead ECG interpretation

practical exercise

Slide 62

JSOMTC, SWMG(A)

Reason

 Ischemic heart disease causes the greatest

number of deaths in the United States.

 50% die before arriving at a hospital.  If treatment is not received within 2 hours

• f onset of symptoms, chance of survival is

25%.

 By treating a heart attack within one hour

• f onset of symptoms, the chance of

survival is 49%!

Slide 63

JSOMTC, SWMG(A)

Reason

 The keys to quick management of an acute

myocardial infarction (AMI) patient are:

• Prompt recognition of the symptoms
• Rapid performance and interpretation of a 12

Lead ECG

• Provide pre‐arrival notification to the receiving

facility