12 Leads Part 2.2 (Eveloution Of A STEMI)

Question 1

Shortly after coronary oclussion ST elevation occurs. After a few hours what notable ECG changes will occur?

Answer 1

• a Q wave will begin to form as the R wave decreases

Question 2

After 24-48 hours what notable changes would you see on an ECG?

Answer 2

• Q wave deepens
• T wave inverts

Question 3

After days/weeks after post infarction what would be notable on the ECG?

Answer 3

• ST segment will begin to normalize
• T wave remains inverted

Question 4

Within the first 30 mins of occlusion (before you see ST elevation) what would you see on the ECG

Answer 4

Hyperactute T waves
- these are asymmetrical
- often 10 mm or 50% of the R wave Height

Question 5

Which leads would you see the hyper acute T wave?

Answer 5

In the anterior leads

Question 6

What are the phases of T wave changes and what occurs in the three of them?

Answer 6

1.hyper acute phase: tall asymmetrical T wave
2. Early acute phase: ST elevation starts to occur and T waves remain tall
3. Later acute phase: elevated ST segment with an inverted T wave

Question 7

In the healed phase (weeks later after occlusion) what would you see on the ECG?

Answer 7

A pathological Q wave with a normal rhythm for the Pt.

Question 8

In the healed phase, what does the pathological Q wave represent?

Answer 8

It’s a result of myocardial tissue death and indicates loss of electrical activity

Question 9

What are characteristics of De Winter T waves?

Answer 9

• Tall SYMMETRIC T waves
• ST segment depression more than 1 mm in V1-V6
• ST elevation in aVR at least 0.5mm

Question 10

In De Winters T waves we see ST elevation at least 0.5mm in AVR. Which coronary artery involvement is this?

Answer 10

Proximal left anterior descending artery involvement

Question 11

ST segment depression can come in three different ways. From most to least indicative of ischemia, name them.

Answer 11

1. Horizontal
2. Down sloping
3. Up sloping

Question 12

Up sloping ST depression is associated with benign conditions such as? (Big Peaks Look Alarming)

Answer 12

• Benign early repolarization
• pericarditis
• LBBB
• aneurysms

Question 13

Ischemia is defined as a lack of oxygenation. This is seen on the ECG as…

Answer 13

ST depression and T wave inversion

Question 14

Myocardial injury is a result of prolonged ischemia. This is seen on the ECG as

Answer 14

ST elevation