Angina Flashcards
What is a distinguishing feature of chronic stable angina?
Symptom reversibility (pain relieved by rest or sublingual nitroglycerine)
What is the MOA of nitrates?
Relaxation of vascular smooth muscle (vasodilation)
Venous dilation is greater than arterial, leading to reduced preload, resulting in reduced O2 consumption
What are the side effects of nitrates?
Hypotension, HA, flushing, light headedness
What are the two specific nitrates commonly used?
Nitroglycerin and Isosorbide mononitrate
What is/are the indications for Nitroglycerin?
Angina (prophylactic and acute)
What interactions should you be conscious of with nitroglycerin?
Avoid use of PDE-5 inhibitors like sildenafil
What is the time of onset and duration of nitroglycerin?
Onset: 1-3 min (sublingual)
Duration: 25 min
What is/are the indications for Isosorbide mononitrate?
Angina pectoris
What interactions should you be conscious of with isosorbide mononitrate?
PDE-5 inhibitors like sildenafil
What is the time of onset and duration for isosorbide mononitrate?
Onset: 30-45 min.
Duration: >6 hrs
Name four natural products that have hypotensive effects and should be used with caution with blood pressure lowering agents?
Coleus, Hawthorn, L-citrulline, and N-acetyl cysteine
Why not combine nitrates with sildenafil?
Hypotension
Are nitrates more specific to arterial or venous blood vessels?
Venous
What are the four roles of therapy for beta blockers in regard to angina?
- Prophylaxis
- Blunt cardiac stimulation
- Prevents reflex tachycardia
- Decreases HR, contractility, and BP
What is the MOA for beta blockers?
Blocks beta adrenergic receptors and can be selective or non-selective to the heart
What are potential side effects of beta blockers?
Bradycardia, heart block, HA, fatigue, dizziness, depression, exercise intolerance, hypotension, erectile dysfunction (varies with selectivity)
What type of agents should you not combine beta blockers with?
Those with intrinsic sympathomimetic activity
What are the primary locations for Beta-1, -2, and -3 receptors?
Beta-1: heart
- 2: lungs (but also on the heart)
- 3: adipose tissue and heart
What can happen with abrupt discontinuation of beta blockers?
Reflex tachycardia (taper gradually)
Metoprolol: MOA?
Cardioselective beta-1 competitive antagonist
Metoprolol: indications?
MI, CHF, angina, HTN
Metoprolol: contraindications?
Heart block or severe bradycardia (HR < 60)
Metoprolol: onset and duration?
Onset: < 1hr
Duration: 3-6 (IR) or 25hrs (ER)
Atenolol: MOA?
Cardioselective beta-1 competitive antagonist
Atenolol: indications?
MI, HTN, angina
Atenolol: contraindications?
Heart block or severe bradycardia
Atenolol: onset and duration?
< 1hr
12-24 hrs
Atenolol: interactions?
Apple
Propranolol: MOA?
Nonselective B1 and B2
Propranolol: indications?
MI, HTN, angina, migraine prophylaxis, supraventricular arrhythmias
Propranolol: contraindications?
Heart block or severe bradycardia
Propranolol: onset and duration?
1-2 hrs
6-12 (IR) or 24 hrs (ER)
Propranolol: interactions
Indian snakeroot and St. John’s Wort
Carvedilol: MOA?
Nonselective w/ alpha-1 adrenergic blockade activity
Carvedilol: indications?
MI, HTN, CHF, angina
Carvedilol: contraindications?
Heart block or severe bradycardia
Carvedilol: onset and duration?
< 1hr
24 hrs
Carvedilol: interactions?
Grapefruit juice
Which beta blockers are more likely to interact with beta agonists used in asthma?
Carvedilol and propranolol
What are the four roles of therapy for Calcium channel blockers in angina?
- Prophylaxis
- Decrease BP
- Dilates coronary blood vessels
- Dilates peripheral blood vessels
What is the MOA for Calcium channel blockers?
Blocks calcium influx leading to relaxation of cardiac and smooth muscles
What are the side effects of calcium channel blockers?
TACHYCARDIA, EDEMA, ha, fatigue, exercise intolerance, hypotension (varies with selectivity)
Calcium channel blockers differ based on their selectivity towards what, which are predominantly found in the periphery?
Dihydropyridine receptors
What are the three dihydropyridines?
Nifedipine
Felodipine
Amlodipine
What calcium channel blocker should you avoid for stable angina?
Immediate release nifedipine
What are the two non-dihydropyridines?
Diltiazem and verapamil
Contraindications for non-dihydropyridines?
Pts w/ ejection fraction < 35% (heart failure)
Cholea, grapefruit, St. John’s Wort
Interactions to avoid with non-dihydropyridines?
Combination with beta blocker (reduces HR)
Amlodipine: indications?
HTN, chronic stable angina, variant angina, disorder of CV system
Verapamil: indications?
HTN, CSA, variant angina, angina, SVT, afib/aflutter
Verapamil: contraindications?
Hypotension, LVEF < 30%, AV block, sick-sinus syndrome, certain arrhythmias
Verapamil: interactions?
Cholea, grapefruit, st. john’s wort
Diltiazem: indications?
Atrial arrhythmia, HTN, SVT, angina
Diltiazem: contraindications?
Hypotension, LVEF < 30%, AV block, sick-sinus, certain arrhythmias
Diltiazem: interactions?
Cholea, grapefruit, st. john’s wort
Why are calcium channel blockers more likely to have drug interactions with other therapeutic moieties?
CYP450 pathways lead to a lot of interactions
Aspirin: MOA?
Nonselective, irreversible COX inhibitor
Aspirin: contraindications?
< 18 years old due to assoc. w/ Reye’s syndrome
Aspirin: interactions?
Cocoa, danshen, dong quai, evening primrose, policosanol, willow bark
Aspirin: metabolism?
Hydrolyzed to salicylate by esterases
Aspirin: side effects?
increased bleeding (GI), disruption of renal perfusion
Do other NSAIDs like aspirin have effects on platelets?
Yes, but they are reversible
Clopidogrel: MOA?
Irreversibly blocks P2Y12 component of ADP receptors on platelet surface (reduces platelet activation)
Clopidogrel: indications?
Post-NSTEMI, ACS, CVA, PCI, and arterial occlusive disease to prevent clots
Clopidogrel: onset?
Detected second day of tx
Clopidogrel: interactions?
Cocoa, danshen, dong quai, evening primrose, policosanol, willow bark, grapefruit, st. john’s wort
Ticagrelor: MOA?
Reversibly blocks P2Y12 component of ADP receptors on platelet surface (duration depends on potency)
Ticagrelor: side effects?
increased risk of bleeding, increased uric acid levels
Ticagrelor: indications?
Prophylaxis post ACS, MI or PCI
Ticagrelor: interactions?
Cocoa, danshen, dong quai, evening primrose, policosanol, willow bark, grapefruit, st. john’s wort
Prasugrel: MOA?
Irreversibly blocks P2Y12 component of ADP receptors on platelet surface
Prasugrel: contraindications?
Prior TIA or stroke (also, increased risk for bleeding with body weight < 60kg)
Prasugrel: interactions?
Cocoa, danshen, dong quai, evening primrose, policosanol, willow bark, grapefruit, st. johns wort
What is different about the P2Y12 pathway that ticagrelor goes through compared to prasugrel and clopidogrel?
Ticagrelor goes through no in vivo biotransformation, whereas prasugrel goes through hydrolysis by esterases and CYP dependent oxidation. Clopidogrel also goes through CYP dependent oxidation
Warfarin: MOA?
Inhibits Vit. K oxide reductase (the enzyme responsible for regenerating vit. K so it can activate clotting factors)
What are the Vitamin K dependent clotting factors?
II, VII, IX, X
Warfarin: onset?
Effects on INR seen 2-5 days after dose changes
Warfarin: interactions [in addition to the usual blood thinner interactors]
Alfalfa, american ginseng, alcohol, EDTA, glucosamine HCL and sulfate, licorice, N-acetyl glucosamine, Vit. K, wintergreen, plus the usuals.
Rivaroxaban: MOA?
Direct, reversible inhibition of factor Xa
Apixaban: MOA?
Direct, reversible inhibition of factor Xa
Dabigatran: MOA?
Direct thrombin inhibitor
Enoxaparin (Low Molecular Weight Heparin): MOA?
Enhances the inhibition rate of clotting proteases by antithrombin III, impairing normal hemostasis and inhibition of factor Xa
Enoxaparin (Low Molecular Weight Heparin): indications?
Typically used as initial treatment and then as bridging therapy
What is the reversal agent for warfarin and how does it work?
Prothrombin complex concentrate (PCC) and fresh frozen plasma (FFP) covers the period before K1 has reached its full effect.