Cardiology: 8.1a: Angina

Question 1

What is stable angina?

Answer 1

chest pain that arises with exertion or emotional stress

Question 2

What causes stable angina?

Answer 2

atherosclerosis of coronary arteries with > 70% stenosis OR vasospasm –> decreased blood flow –> not able to meet the metabolic demands of the myocardium during exertion

Question 3

How much stenosis of the coronary arteries is required before angina occurs?

Answer 3

> 70%

Question 4

How much of the myocardium receives damage due to stabile angina?

Answer 4

none- it’s reversible and no necrosis occurs

Question 5

What are the s/s of stable angina?

Answer 5

• chest pain (lasting less than 20 mins)
• pain radiates to L arm or jaw
• diaphoresis
• SOB

Question 6

What relieves stabile angina?

Answer 6

• rest
• nitro

Question 7

What EKG findings are seen in stabile angina? Why?

Answer 7

ST-segment depression due to subendocardial ischemia

Question 8

What is unstable angina?

Answer 8

chest pain that occurs at rest (or increased frequency or intensity of said pain)

Question 9

What causes unstable angina?

Answer 9

rupture of an atherosclerotic plaque with thrombosis –> incomplete occlusion of a coronary artery

Question 10

What is the hallmark of reversible cell injury?

Answer 10

cellular swelling

Question 11

How long does chest pain last in stable angina?

Answer 11

less than 20 minutes

Question 12

From superficial to deep, what are the 3 muscle layers of the heart?

Answer 12

1. Epicardium (most superficial)
2. Myocardium (middle)
3. Endocardium (deepest)

Question 13

Which area of heart muscle is most susceptible to ischemic damage?

Answer 13

the subendocardium

Question 14

Why does nitro relieve stabile agina?

Answer 14

vasodilation of the veins –> decreased preload –> decreased stress on myocytes –> decreased O2 demand

Question 15

Why does rupture of an atherosclerotic plaque cause thrombosis?

Answer 15

exposure of subendothelial collagen and necrotic material –> activation of clotting cascade –> thrombosis

Question 16

Does unstable angina result in reversible or irreversible injury?

Answer 16

reversible

Question 17

What does unstable angina look like on ECG? Why?

Answer 17

• ST-segment depression
• predominantly subendocardial ischemia

Question 18

What relieves unstable angina?

Answer 18

nitroglycerin

Question 19

Is there a risk that unstable angina will progress to MI? Why or why not?

Answer 19

YES- high risk bc the thrombus could grow to full occlusion of the vessel

Question 20

What causes Prinzmetal/variant angina?

Answer 20

coronary artery vasospasm (@ rest)

Question 21

Does Prinzmetal/variant angina cause reversible or irreversible injury?

Answer 21

reversible

Question 22

What does Prinzmetal/variant angina look like on ECG? Why?

Answer 22

STEMI bc of transmural ischemia

Question 23

How can you differentiate Prinzmetal/variant angina from unstable angina?

Answer 23

• both occur at rest and are relieved with NO
  
  • Prinzmetal/variant angina = STEMI; relieved w/ Ca++ channel blockers
  • unstable angina = ST depression

Question 24

What relieves Prinzmetal/variant angina?

Answer 24

• nitroglycerin
• Ca++ channel blockers

Question 25

What layer of the myocardium is affected by Prinzmetal/variant angina?

Answer 25

all three layers (epi, myo, endo) = transmural ischemia

Question 26

Why do Ca++ channel blockers relieve Prinzmetal/variant angina?

Answer 26

they help relieve the coronary artery vasospasm

Question 27

What kind of angina does a STEMI indicate?

Answer 27

Prinzmetal/variant angina

Question 28

What kind of angina does ST-segment depression indicate?

Answer 28

• stable angina
• unstable angina

Question 29

Usually the trigger in Prinzmetal/variant angina is unknown, but name 3 known triggers.

Answer 29

1. tobacco
2. cocaine
3. triptans