Flashcards in Angina 1 Deck (12)
what is angina?
a clinical syndrome characterized by discomfort in the chest, jaw, shoulder, back and or arm
1) typically aggravated by exertion or emotional stress
2) relieved by nitroglycerin
what is the drug that can be used as an alternative to aspirin?
what are the 4 characteristics of ticlopidine?
1. thienopyridine derivative that inhibits platelet aggregation induced by adenosine diphophate
2. also reduces blood viscosity by decreasing plasma fibrinogen and increases red cell deformability
3. has no shown a decrease in adverse events in pts with stable angina
4. induces neutropenia and rarely TTP
how is clopidogrel different from ticlopidine?
has greater antithrombotic effect than ticlopidine
what is the mech of ticlopidine?
selectively and irreversible inhibits the binding of adenosine diphosphate to its platelet receptors
--> this blocks adenosine diphosphate - dependent activation of the glycoprotein IIb/IIIa complex
what is the mech of prasugrel?
irreversibley binds to the P2Y12 receptor --> it is a G protein coupled chemoreceptor for ADP
what is ticagrelor?
1. similar in structure to adenosine, like the thienopyridiens, it blocks ADP receptors
--> its binding site is different from ADP, it is a reversible blockade
2. does NOT require hepatic activation thus can be used for pt with liver failure
what is dipyridamole?
a pyrimido-pyrimidine derivative that increases intracellular platelet cyclic AMP
1) inhibits phosphodiesterase
2) activates adenylate cyclase
3) inhibits uptake of adenosine from vascular endothelium and RBCs
what caution is needed when dipyridamole?
use is limited b/c it vasodilates coronary arteries which can enhance exercise induced ischemia
what is cilostazol?
a quinolinone derivative that inhibits cellular phosphodiesterase
--> increase cAMP --> inhibits platelet aggregation
* also causes vasodilation which is felt to be the cause of the increased morbidity and mortality seen in heart failure patients
what are the metabolic effects of ishcemia?
elevated extracellular potassium is the most important contributor to the electrophysiologic changes of ischemia
--> increased cell membrane permeability to potassium during the plateau phase of the action potential results in the increased K+ leak outwards
--> lactate and phosphate follow the potassium out