CAD Essentials Flashcards
Atherosclerotic heart disease…
What is the effect?
- Narrows the lumen of the vessel
Reducing blood flow to the area supplied by the artery - Reduces elasticity
Making it less resilient in the face of volume or pressure changes. - Increases risk of plaque rupture & subsequent
clot formation
with further occlusion & potential embolization - Increases risk of vasospasm
Atherosclerosis risk factors:
Non-modifiable:
- Heredity (family Hx of premature CV disease)
- Age
o Men older than 45
o Women older than 55 – postmenopausal
- Race (higher incidence in black)
- Sex (men develop CAD earlier than women)
Modifiable:
- HTN
- Hyperlipidemia
- DM
- Smoking
- Stress
- Obesity
- Sedentary lifestyle
- Depression
ACS?
Inclues MI, unstable angina, and sudden cardiac death
How far does coronary artery blood flow have to be obstructed before symptoms appear?
75%
Under what circumstances does the 02 demand become greater than the 02 supply in the heart?
1) Increased workload on the heart in the face of a fixed supply. (eg: hypertension, aortic stenosis, increased metabolic demand)
2. Reduced blood supply to the heart. (eg: atherosclerosis coronary artery vasospasm thrombus/embolus)
3. Reduced oxygen carrying capacity of coronary arteries (anemia, hemodilution, acute blood loss)
How to reduce O2 demand on heart in plan of care for patient experiencing CAD/angina?
Rest
Oxygen
Nitrates
Morphine
Beta blockers
Ca channel blockers
ACE Inhibitors/ARB
**Reduce workload of heart
How to inc O2 supply available in care for a patient with CAD/angina?
Aspirin 160-325 mg chewed
Fibrinolytics
PCI (Percutaneous Coronary Interventions)
Coronary Artery Bypass
Heparins
Antiplatelets
HMG Coenzyme A Reductase
Inhibitors (Statins)
General actions for management of ischemia?
MONA
Morphine Oxygen Nitrates Activity / Aspirin ** NOT necessarily in this order!
What do nitrates do?
relax vascular smooth muscle ie arteries (including coronary arteries) but particularly veins…reducing preload and consequently reducing cardiac workload.
Worst case scenario in taking nitrates? How to know? What would you do?
Vessels dilate too much and blood pools in periphery»_space; reducing CO
… fill the space with isotonic volume.
headache
adverse effects =
headache, tachycardia, postural hypotension
What does morphine do to help with angina?
opiod narcotic analgesic…reducing SNS activity
relaxes vascular smooth muscle, particularly veins…reducing preload
»>consequently reducing cardiac workload.
What is the worst thing that can happen if someone takes morphine? How would you know? What would you do?
Vessels dilate too much and blood pools in periphery»_space; reducing CO
Respiratory depression»_space; arrest
»> Naloxone
What do Beta blockers do?
reduction in cardiac output (stroke volume) by blocking beta receptors
Worst case scenario with beta blockers? What would you do?
- bradycardia
- inadequate cardiac output
- bronchospasm ( in non-selective beta blockers)
What do calcium channel blockers do?
relaxation of vessel walls through blocking of calcium ion channels
»> reduce afterload & consequently cardiac workload
Worst case scenario with calcium channel blockers?
- bradycardia (heart block)
- inadequate cardiac output
- heart failure
Which drug cannot be mixed with grapefruit juice?
Ca channel blockers
Worst case scenario with ACE inhibitors?
- inadequate cardiac output
- cough (angioedema) from action on vasodilator bradykinins
Worst case scenario with aspirin? (ASA)
Allergic reaction»_space; antihistamine/epinephrine
bleeding? (not in slides)
What does ASA do to aid with ischemic pain/angina/CAD?
Anti-inflammatory
Anti-platelet
Reduces mortality by up to 23% (ISIS 2)
When are fibrinolytics used for STEMI?
For STEMI if /s onset is within 12 hours and PCI is not available within 90 minutes of first medical contact
Why to be cautious with fibrinolytics?
Dissolves body’s fresh fibrin clots…all of them!! (risk for bleeding of other clots in place post surgery, etc for healing)
»_space;> the diagnosis has to be right!
* Typically delivered in critical care settings
What is percutaneous conoary interventions?
Ex: putting in stent (angioplasty)
LMWH advantages?
Less likely to cause thrombocytopenia
Duration of action is 2- 4x’s longer than regular Heparin od vs. bid
LMWH’s produce a more stable response than heparin
Hence, less follow-up lab tests are needed
What do antiplatelets do?
Reduce platelet aggregation
What do Statins do? (HMG Coenzyme A reductase inhibitors)?
inhibit cholesterol production
20-40% reduction in LDL, raise HDL levels, and lower triglycerides
What is the worst thing that can happen if someone takes statins?
liver dysfunction can occur – LFT tests need to be done prior/3months post
Muscle pain, tenderness and weakness – check CPK – Creatinine phosphokinase – may d/c drug
n/v, heartburn, abdominal cramping and diarrhea – give with meal in evening.
Diagnostic tests for CAD?
-CK
-CK-MB
-Myoglobin
-Troponin I and T (Specific cardiac markers)
-ECG
- Echocardiogram (see EF)
- Stress testing
- Angiogram
-
Does Troponin I and T evelate immediately after MI?
Enzyme detected 2-6 hrs. after MI, peaks 15-24 hrs, returns to normal within 7 days.
ECG
Does this give info about heart damage?
Measures the electrical activity of the heart, not the mechanical
Looks at the rhythm of the heart
Can give information of areas of the heart that are damaged (**but NOT best indicator for detecting extent of damage…look at troponin)
Used to help diagnose acute coronary syndrome (ACS)
What does an echocardiogram show?
Sound waves create an image of the heart in motion to …
1) Evaluate heart wall motion
2) Identify valvular disease
3) Evaluate the heart under stress
4) Identify & quantify pericaridal fluid
**Can see Ejection Fraction
What is measured during cardiac stress test?
Patients ECG and BP are monitored during exam.
WHat is cardiac stress testing done for?
Used to evaluate possible heart damage or to evaluate the potential risk of future heart damage
Goal in medical management of CAD/angina?
to dec O2 demand to heart and inc O2 supply
