Cardio: Drugs for Stable Angina Flashcards
Are pharmological drugs the #1 choice for increasing coronary blood flow in ACS?
Nope. Treat w PCI (Stent or balloon)
The vessels are usually maximally dilated so giving a vasodilator does not help.
What are the ways to reduce O2 demand in stable angina?
Decrease HR and Contractility
Decrease Pre and Afterload
MOA of Nitrates
- Broken down into NO, which activates cGMP
* *2. cGMP activates Protein Kinase G
- causes Relaxation of smooth muscle
- also blocks K+ entry to hyperpolarize cells
MOA of Nitrates specifically for Stable Angina?
Vasodilators of Veins
-Reduce preload=reduced O2 demand
Should people take a day off of nitrates?
Yes, they quickly develop tolerance and increase generation of superoxide radicals (reduce Thiols)
Additionally cause Na and water retention
What are the clinical uses of nitroglycerin and the oral forms, Isosorbide mononitrate and dinitrate?
Sublingual nitro is great for relieving acute angina
Oral forms are longer acting and can prevent attacks
Adverse effects of nitrates?
Headache
Orthostatic hypotension
Increased Na and H20 retention
What is nitrates effect on HR?
Increased
-reflex tachy
Would you give nitrates along with PDE-5 inhibitors, such as sildenafil, vardenafil, and tadalafil?
No! Causes a severe drop in BP
Which Ca+ channel blockers work in the vascular smooth muscle and which work in the heart?
Both Dihydropyridines and Non-dihydropyridines dilate arterioles
Only Non-dihydropyridines work on the cardiac muscle and pacemaker cells
What are the dihydropyridine CCBs?
-dipines
Amlodipine (long acting), nifedipine, and nicardipine
What are the non-dihydropyridine CCBs?
Verapamil and diltiazem
What CCBs decrease cardiac contractility and reduce HR?
- Verapamil (most potent)
2. diltiazem
MOA of CCBs?
Decrease PVR and Afterload (both)
Decrease cardiac contractility and HR (non-dihydropyridine only)
Major adverse effects of cardioactive CCBs?
Cardiac depression, arrest, HF, bradyarrythmias and AV block
Severe hypotension
Which CCB increases risk of MI in patients with hypertension?
Nifedipine
MOA of B-blockers?
Reduce sympathetic activity
-decrease HR, cardiac contractility, and drop BP (decrease afterload)
All leads to increased heart perfusion
Adverse effects of B-blockers?
Reduced CO
Bronchoconstriction
Impaired glucose mobilization
Increase LDL, decrease HDL
Withdrawl syndrome!
Contraindications of B-blockers
Asthma and COPD* PVD Type 1 diabetics Bradyarrythmias Severe cardiac depression
MOA of Ranolazine
Closes late Na+ in ischemic myocardium to reduce Ca overload
-normalizes repolarization of cardiac myocytes
Does ranolazine affect HR or vasodilation?
NO!
When would you use ranolazine?
Refractory stable angina
-decrease anginal episodes and improves exercise tolarance in those taking nitrate, amlodipine, atenolol
What effect to nitrates alone have on contractility?
Reflexive increase
-just like HR
What effect do BB or CCBs have on EDV and Ejection time?
Reduces contractility, so increases EDV and ejection time
-reduces everything else (HR, BP)
What is best approach when prescribing BB, nitrates or CCBs for angina?
Combine Nitrates with either BB or CCBs to reduce the reflexive tachy and contractility
First line in treating prinzmetal angina?
Diltiazem or amlodipine
-long acting nitrates are used when CCBs contra
MOA of asparin
COX 1/2 irreversible inhibitor to reduce TBXA2
-reduces aggregation of platelets
MOA of clopidogrel, prasugrel, and ticagrelor?
Blocks P2Y12, increases cAMP=reduced platelet activation
-reduces aggregation by reducing GIIb/IIIa on receptor of platelets
What are the thrombolytic drugs?
TPA drugs (end in -plase) -alteplase, reteplase, and tenecteplase
Streptokinase
Anti-platelet drugs prevent ___ thrombi formation
White thrombi
When would you use asparin?
Started as soon as possible in Acute coronary events
-also prevents secondary coronary events
Adverse effects of asparin
GI bleeds
Hypersensitivity to Asparin
What CYP can predispose someone to clopidogrel resistance?
nonfunctional CYP2C19
-needed for activation of clopidogrel
Clinical use of Clopidogrel?
Dual antiplatelet therapy or alone if pts allergic to asparin
What are the GIIb/IIIa inhibitors?
Abciximab
Eptifibatide
Tirofiban
MOA of the GIIb/IIIa inhibitors?
block GIIb/IIIa to prevent platelet aggregation
Are the GIIb/IIIa inhibitors used much now?
Only really in PCI in high risk pts
Adverse effects of GIIb/IIIa inhibitors
Bleeding and thrombocytopenia (more abciximab)
When are the thrombolytics used?
Used in STEMI/NSTEMI when PCI isnt available
-goal is within 3-4.5 hours
Adverse effects of thrombolytics?
Bleeding and allergic rxns (streptokinase mainly)
