Coronary Artery Disease

Question 1

What is coronary artery disease?

Answer 1

Disease of coronary arteries that supply the heart.

Can be asymptomatic or develop into stable angina

Unstable angina + MI = more serious manifestations of CAD (acute coronary syndrome)

Question 2

What is the major cause of CAD?

Answer 2

ATHEROSCLEROSIS

• deposition of lipids within the intima of the artery
• C-reactive protein (CRP) is released by the liver and is increased during system inflammation AND unstable plaques and oxidation of LDLs

Question 3

Steps of atherosclerosis

Answer 3

1) Damaged endothelium
- d/t hypertension, smoking, hyperlipidemia, hyperhomocysteinemia, diabetes, infection, toxins

2) Fatty streak
- lipids accumulate and migrate into SMCs

3) Fibrous plaque
- collagen covers the fatty streak
- vessel lumen is narrowed, reducing blood flow
- fissures can develop

4) Complicated lesion
- plaque rupture
- thrombus formation
- further narrowing or total occlusion of vessel

Question 4

Stable Angina vs unstable angina

Answer 4

STABLE

• occlusion that is reversible w/ rest + use of nitroglycerin
• onset, pattern, and duration is predictable and same each time

UNSTABLE

• unstable plaque and lesion that intermittently occludes and opens
• may lead to a complete MI
• irreversible cell death and necrosis
• different type and quality of pain than that of stable angina

Question 5

What is collateral circulation?

Answer 5

Arterial anastomoses or connections

• the body’s way of compensating when an artery becomes occluded due to atherosclerosis or CAD
• grwoth of connections increases in the presence of chronic ischemia

Question 6

Is there collateral circulation in rapid onsets of CAD?

Answer 6

NO
When CAD has a rapid onset, or coronary spasm occurs, there may not be enough time for collateral circulation development
Diminished arterial blood flow ==> more severe ischemia ==> infarction

Question 7

2 types of angina

Answer 7

Angina is the clinical manifestation of reversible ischemia

CHRONIC STABLE

• chest pain that occurs intermittently over a period w/ the same pattern of onset, duration, and intensity of symptoms
• constrictive, squeezing, heavy, choking, suffocating sensations
• pain is brief (3-5 mins) and goes away w/ rest
• precipitated by physical demand

PRINZMETAL ANGINA

• chest pain that occurs at rest randomly
• spasms of a major coronary artery

Question 8

What should you do when a pt complains about chest pain?

Answer 8

1) take vitals
2) administer O2
3) 12 lead ECG

4) Administer nitrates and baby aspirin
- nitroglycerin spay

5) listen to heart sounds
S3 - transient - related to hyperdynamic state
- lots of fluid - makes a swishing sound against ventricle walls
- usually the first symptom of congestive heart failure

S4 - pathological sound

• usually there all the time
• resistance to ventricular filling bc they are stiff and noncompliant

Question 9

Goals

Answer 9

Goals
- Pain relief
- Preservation of myocardium
- Immediate and appropriate treatment
- Effective coping w/ illness-associated anxiety
- Participation in a rehabilitation plan
- Reduction of risk factors
- Health promotion
○ Therapeutic lifestyle changes to reduce cardiac risk factors

Question 10

How to diagnose CAD

Answer 10

ECG
BLOOD WORK 
- cardiac markers (myoglobin, CK-MB, Troponin I)
- CK-MB and troponin I are specific to cardiac muscle cells; are released when cells are dying 
- lipid profile to assess risk factors
- CBC
- chemistry
-pt/INR
CXR
2D ECHO
CARDIAC ANGIOGRAM

Question 11

Goal of drug therapy in CAD

Answer 11

Increase O2 supply

Decrease O2 demand

Question 12

What meds are given to pts w/ CAD

Answer 12

ASPIRIN

• inhibit COX1 + COX2 (to prevent the production of thromboxane A2, a platelet activator)
• administer as soon as acute coronary syndrome is suspected

PLAVIX

• inhibit platelet aggregation
• alternative for pts who cannot use aspirin
• decrease risk of blockage

NITRATES
- promotes peripheral vasodilation
- decreases preload and afterload 
promote coronary artery vasodilation 
- reduces myocardial O2 consumption 

BETA BLOCKERS ** preferred**

• inhibit symNS stimulation of heart
• reduce HR and contractility
• decrease afterload
• reduces workload and O2 demands

CA2+ CHANNEL BLOCKERS

• prevent Ca2+ entry into myocytes and vascular SMCs
• promote coronary and peripheral vasodilation
• reduce HR + contractility
• • reduce workload + O2 demand

ACEi

• prevent conversion of angiotensin I –> angiotensin II
• decrease endothelial dysFN
• useful in treating heart failure, tachycardia, MI, hypertension, diabetes, CKD

Question 13

non-modifiable risk factors for CAD

Answer 13

age 
gender: risk is > men 
ethnicity: caucasian 
family Hx
genetic predisposition

Question 14

Modifiable risk factors for CAD

Answer 14

• elevated serum lipids: blood cholesterol, LDL > HDL
• HTN: BP > 140/90
• tobacco use
• physical inactivity
• obesity: higher LDLs + HTN
• diabetes: incidence is 2-4X higher
• metabolic syndrome
• psychological states: type A personalities (greater stress, suppress anger)
• homocysteine level: breakdown of methionine that occurs when the inner lining of BVs becomes damaged
• substance use

Question 15

What does health promotion involve for CAD?

Answer 15

ID high-risk individuals
management for high-risk pts
physical activity
health education in schools
nutritional therapy 
- lower LDLs, increase HDLs
- diet high in complex carbs + fiber
- omega 3 FAs reduce risks associated w/ CAD
- pts w/ CAD are encouraged to take EPA and DHA supplements

Question 16

location of:

• nasogastric
• nasoenteric
• gastrostomy
• jejunostomy

Answer 16

NG - stomach
Nasoeneteric - duodenum
Gastrostomy - stomach
jejunostomy - jejunum

Question 17

What to document after gastric tube insertion

Answer 17

• length, size, type of gastric tube used
• location of insertion
• pts tolerance of the procedure
• character of gastric contents and pH
• results of radiography
• intake output