Ischemic Heart Disease (Exam IV)- grayson Flashcards
What chemical mediators are released from ischemia that activate cardiac nociceptors?
Adenosine and Bradykinin
What is the path for cardiac pain signals to reach the spinal cord?
Cardiac nociceptors → Afferent Neurons → T1 - T5 SNS ganglia.
how does our heart respond to release of adenosine and bradykinin?
- ↓ AV conduction and thus ↓HR
- ↓ Contractility
Differentiate stable vs unstable angina.
- Stable - No change in chest pain severity or frequency in 2-mo period.
- Unstable -angina at rest, angina new onset, or CP increasing in frequency and/or severity without increase in cardiac biomarkers
Are cardiac biomarkers (troponin) present with unstable angina?
NO. If they were, that would be an MI.
What EKG abnormality is associated with old MI’s and/or current ischemia?
T-wave inversion
What is nuclear stress testing utilized for?
Coronary Perfusion assessment
What determines the significance of CAD during a nuclear stress test?
Size of the perfusion abnormality
Arrows point to arrows of lesser perfusion.
What test can differentiate a new vs and old perfusion abnormality?
Nuclear Stress Testing
What nuclear stress test tracers are used with exercise?
Thallium
What nuclear stress test drugs are used without exercise?
Atropine
Dobutamine
Pacing
When are adenosine and dipyridamole for nuclear stress testing? Why?
Used after test to dilate normal, non-ischemic areas of the heart.
What test would be useful for imaging wall motion abnormalities or valvular function?
Echocardiography
What is Prinzmetal Angina?
Coronary Spasm
What is the mechanism of action for aspirin?
COX-1 Inhibition → TXA2 inhibition → Plt aggregation inhibition.
How can aspirin be reversed?
Trick question. It can’t be, platelets are damaged until they die and are replaced.
What is the mechanism of action of abciximab, eptifibatide, and tirofiban?
Plt glycoprotein IIb/IIIa receptor antagonists
Inhibit platelet activation, adhesion, and aggregation.
What drugs (discussed in lecture) are P2Y12 inhibitors?
Clopidogrel and Prasugrel
What common drug class will antagonized P2Y12 inhibitors?
PPIs
How does Prasugrel compare to Clopidogrel?
Prasugrel has more predictable pharmacokinetics and greater bleeding risk.