CVD: heart attack

Question 1

What is a heart attack? Cause?

Answer 1

= Myocardial infarction = tissue death from lack of blood flow (necrosis). Happens bc of the complete blockage of a coronary artery.

Question 2

Which is more often affected in a heart attack: the left or right ventricle

Answer 2

Left ventricle

Question 3

Which arteries to the heart can be blocked and with which %?

Answer 3

1. Left anterior descending artery (40-50%)
2. Right coronary artery (30-40%)
3. Left circumflex artery (15-20%)

Question 4

After how many minutes does the myocardium muscle become an irreversible zone of necrosis?

Answer 4

20-40 minutes

Question 5

What is a subendocardial infarct?

Answer 5

= blood supply recovers, but inner membrane (“inner third”) of the heart is damaged. Shown on ECG with St-segment depression

Question 6

What is the heart attack called after 3-6 hours ? What happens on the ECG?

Answer 6

All of the muscle tissue is becoming a site of necrosis: transmural infarct, ST-segment elevation

Question 7

Symptoms of a heart attack?

Answer 7

• chest pain/pressure -> left arm/jaw referred pain
• Diaphoresis (sweating)
• nausea
• fatigue
• dyspnea

Question 8

How to diagnose whether one has had a heart attack?

Answer 8

Heart cells die -> proteins enter blood stream, of which three key ones are:

Troponin i
Troponin T
CK-MB (helpful for second infarct, because the amount of enzymes will drop quicker)

They can be measured

Question 9

Interventions/medication for heart attack:

Answer 9

Surgery:
- balloon to open artery = angioplasty
- stent
- Coronary artery bypass surgery (blood vessel is taken from another part of your body and is used to help blood flow around the blockage)

Medicine:
-antiplatelents (aspirin)
- anticoagulants
- beta blockers (slow heart rate)
- pain medication
- statins (improve lipid profile)

Long-term: diet, smoking, exercise

Question 10

What are ways to diagnose heart attack?

Answer 10

Heart attack can be diagnosed by elevated serum concentrations of
- Troponin i&T
- Creatin kinase CK-MB (shorter time frame)
 The troponin assay provides prognostic information: a high serum troponin level= increased mortality risk

Question 11

What tests can be done to determine how affected the heart is after heart attack?

Answer 11

• Echocardiogram: ability to assess whether certain parts or functions of the heart have been compromised due to atherosclerosis
• Exercise stress test: a person uses a treadmill while doctors monitor and measure blood pressure and an ECG (sometimes called EKC). ECG measures the electrical activity of the heart. ECG can, for example, detect how much of the wall of the heart muscle is affected after a myocardial infarction.
• Coronary angiography: special dye is injected into the arteries, blockages/narrowing is better visible
• CT scan
• MRI