Ischemia

Question 1

What are some causes of ischemic heart disease?

Answer 1

narrowing of arteries: - atherosclerosis - severe HTN/tachycardia - coronary artery vasospasm - hypoxia - severe hypotension - anemia - severe AI or AS

Question 2

Clinical manifestations of IHD

Answer 2

• angina pectoris - myocardial ischemia/infarct - arrhythmias - ventricular dysfxn - sudden death

Question 3

Risk factors of IHD

Answer 3

-male -elderly -sedentary -genetic - smoker - DM -dislipidemia -HTN - CAD/vascular disease -obesity - high estrogen BC - menopause - type a personalities

Question 4

your patient has an occlusion of the RCA. What part of the heart is affected and what leads would you see changes?

Answer 4

Inferior wall changes in II, III, avF

Question 5

your patient has an occlusion of the Left circumflex. What part of the heart is affected and what leads would you see changes?

Answer 5

Lateral wall changes in I, aVL, V5, V6

Question 6

your patient has an occlusion of the Left anterior descending coronary artery. What part of the heart is affected and what leads would you see changes?

Answer 6

Anterior

V1-V4

Question 7

Ischemic heart disease is characterized by:

Answer 7

imbalance between O2 supply and demand

Question 8

Define atherosclerosis

Answer 8

Fatty substances such as cholesterol, cellular waste products and calcium build up in the lining of arteries.

Question 9

what substances are released during ischemia? what are the actions of these substances?

Answer 9

bradykinin and adenosine.

• Chest pain (thalamic and cortical stimulaion)
• Slow AV node conduction, decrease contractility (balance O2 supply demand)

Question 10

What is the difference between stable and unstable angina?

Answer 10

Unstable angina is any new changes in chest pain (longer duration, increased frequency, not relieved by NTG, precipitating factors ie used to walk 3 blocks before SOB, now can only walk 1 block)

Question 11

Unstable angina is a signal for:

Answer 11

impending MI. don’t take the pt to OR!!

Question 12

What is stunning, hibernation and preconditioning?

Answer 12

Stunning- brief periods of ischemia the resolves in several hours

hibernation - ongoing dysfunction d/t impaired coronary blood flow. resolves with return of blodo flow.

preconditioning - intermittent periods of ischemia to provide protection against larger ischemic events (exercise, pacers, opioid, volatile anesthetics)

Question 13

How do the volatile anesthetics we use precondition the heart for ischemic events?

Answer 13

block the triggers

Question 14

Prinzmetal angina is often associated with other vasospastic dz. what are examples?

Answer 14

Raynaud’s, migraine headaches

Question 15

T/F: Prinzmetal angina can occur in a normal vessel.

Answer 15

True. CORONARY SPASM is the main concern. these spasms don’t discriminate.

Question 16

lifestyle mods that we can educate our patients about

Answer 16

smoking cessation

diet

exercise

Question 17

Drugs for managing IHD

Answer 17

Beta blockers - decrease HR/contractility

CCB - dilate coronary arteries, decrase contractility and afterload

ACE-I decrease contractilty/afterload

Nitrates - dilate coronary arteries, collateral vessels, decrease preload (venodilation) and afterload (dec periph vasc resistance)

Antiplatelet - decrease risk for thrombosis

also diuretics

Question 18

what happens when a plaque ruptures?

Answer 18

1. plt aggregation
2. thromboxane A (vasoxcx)
3. GII/b III/a activation (inc plt aggregation)
4. fibrin deposits
5. thrombus
6. angina, microemboli, infarct, spasm, and/or sudden death

Question 19

infarction occurs how long after ischemia?

Answer 19

20-30 mins.

reaches full size in 3-6 hrs.

Question 20

3 criteria for diagnosis of MI

Answer 20

1. chest pain
2. serial EKG
3. inc/dec cardiac enzymes

perform cardiac MRI to determine extent of MI.

Question 21

how do we treat MI?

Answer 21

eval hemodynamics - check the VS!!

12-lead EKG

O2

Morphine/NTG

ASA/clopidogrel

Question 22

ACE-I are appropriate adjuncts to therapy if:

Answer 22

1. Anterior wall MI (LAD)
2. EF <40%,
3. Diabetic

Question 23

Some complications of infarct:

Answer 23

1. arrhythmias
2. LVF/ CHF, +/- pulm edema
3. cardiogenic shock
4. thromboembolism - stroke
5. papillary muscle dysfxn - valve disease
6. external rupture of infarct >>tamponade>>death (4-7 days post)
7. ventricular aneurysm
8. acute pericarditis (2-4 days post)

Question 24

Things that decrease O2 supply:

Answer 24

Tachycardia

hypotension

vasoconstriction

dec O2 carrying capacity

acid-base

anemia

hypoxia

viscosity

coronary spasm

Question 25

things that increase O2 demand:

Answer 25

Tachycardia

increased preload, afterload, contractility

shivering

hyperglycemia

HTN

Question 26

Is regional anesthesia contraindicated?

Answer 26

not if coags are fine.
pretreat hypotension with phenylephrine

bradycardia - use ephedrine