Pharmacology - Anti-Anginal Drugs (Exam 4) Flashcards
Heart-attack like symptoms due to emotional and physical stress; more prone to post-menopausal women
Takotsubo cardiomyopathy (broken heart syndrome)
Which part of the heart is affected in Takotsubo cardiomyopathy (broken heart syndrome)?
Left ventricle is enlarged
(looks like an octopus pot)
What are the symptoms of Takotsubo cardiomyopathy (broken heart syndrome)? (8)
Angina pectoris (sudden severe chest pain)
Shortness of breath
Arrhythmia
Cardiogenic shock
Fainting
Low BP
Heart failure
Nausea
Chest pain
Angina pectoris
Usually manifested as severe, transient, retrosternal pain that can radiate to arms, back, or jaw
Angina pectoris
What is the cause of angina pectoris?
Cardiac ishemia/hypoxia
What is the main culprit of angina pectoris?
Atherosclerosis (coronary artery disease)
What are the 4 risk factors of atherosclerosis?
- High cholesterol
- High BP
- Diabetes
- Genetics
What are the steps leading to angina pectoris? (10)
- Stress/exertion
- Sympathetic discharge
- Catecholamine release (epi + norepi)
- Vasoconstriction
- Increased venous return, preload, HR, & O2 demand
- Autoregulation
- Coronary artery dilation
- Atherosclerosis of coronary artery causes narrowing & fixed blood flow
- Cardiac ischemia
- Angina pectoris
What are the 4 types of angina pectoris?
- Stable
- Unstable
- Variant
- Cardiac syndrome X
Which types of angina pectoris are caused by atherosclerosis (coronary artery disease)
Stable
Unstable
Which type of angina is described as vasospastic or prinzmetal (abnormal coronary artery spasm)?
Variant
Which type of angina is described as microvascular and has signs associated with decreased blood flow to heart tissue, but with normal coronary arteries?
Cardiac syndrome X
What type of angina?
Pain during stress and exertion
Predictable and manageable
Stable plaque
Stable
What type of angina?
Sudden, irregular, unpredictable (even at rest)
Sudden platelet aggregation or plaque breaking away from an artery wall
Unstable plaque
Unstable
Which angina is a “walking time bomb” for myocardial infarction?
Unstable
What is an example of non-pharmaceutical management for atheroscleorsis?
Stent with balloon angioplasty
What is the balloon coated with for an angioplasty?
Drugs to prevent clotting
T/F stent with balloon angioplasty is a transient solution for atherosclerosis
True
What type of angina?
Pain at rest, often when sleeping
Caused by vasospasm of coronary artery
Variant (aka vasospastic or prinzmetal)
What is the mechanism for drugs for angina pectoris?
Increase O2 supply
Increase coronary blood flow
Decrease cardiac workload
Decrease O2 demand
What are the 3 types of drugs used for angina pectoris?
- Nitrates/nitrites
- Ca2+ channel blockers
- B blockers
Which drug is a nitrate/nitrite?
Nitroglycerin
Nitrates/nitrites are a component of what?
Nitric oxide
What does nitric oxide cause at low doses vs high doses?
Low doses = vasodilation in veins
High doses = vasodilation in arteries
T/F nitric oxide is a free radical gas
True
What was previously known as endothelium-derived relaxation factor?
Nitric oxide
What happens when nitric oxide dilates arteries at high doses?
Increase coronary blood flow
Increase O2 supply
What happens when nitric oxide dilates veins at low doses?
Decrease venous tone, preload, CO, O2 demand
T/F nitric oxide (NO) is the same as nitrous oxide (N2O)
FALSE, they are NOT the same
Explain how nitrates cause relaxation (5 steps)
- Nitrate enters SM cell and becomes NO
- NO causes guanylyl cyclase + GTP to become cGMP
- MLC phosphatase is activated
- Increase in myosin LC
- Relaxation
What breaks down cGMP to GMP in the SM cell to cause contraction?
PDE (phosphodiesterase)
What can inhibit PDE to prevent the break down of cGMP to GMP in the SM cell (prevents contraction)?
Sildenafil (PDE-5 inhibitor)
(aka Viagra)
Which drug is used for acute episodes of angina pectoris?
Nitroglycerin
Which drug is administered via sublingual tablets, has a rapid onset of 1-3 mins, and a duration of 30-60 mins?
Nitroglycerin
What is another form of Nitroglycerin administration?
Skin patch (for slow, continuous release)
T/F Nitroglycerin is unsuitable for long-term prophylaxis
True
T/F Nitroglycerin is metabolized via first-pass
True
Which drug must be kept in emergency kits in dental offices?
Nitroglycerin
Which drug is a NO donor?
Isosorbide dinitrate
Isosorbide dinitrate comes in _____________ formulations
long-acting
What is a problematic side effect of isosorbide dinitrate?
Tolerance
What is the mechanism of isosorbide dinitrate?
NO decreases platelet aggregation/adhesion in acute myocardial infarction
What are adverse effects of nitrates and nitrites?
Headache
Tolerance
Hypotension (reflex tachycardia)
Cerebral ischemia
Syncope (when standing still or w/ alcohol)
Which nitrate/nitrite drug is contraindicated for use in pregnant women?
Amyl nitrite
(“my pregnant friend Amy can’t take Amyl nitrite”)
What does amyl nitrite cause in pregnant women?
Dramatic decrease in placental blood flow
What is a drug cannot be taken with nitrates and nitrites?
PDE-5 inhibitors (ex: Slidenafil/Viagra)
What can happen if you combine nitrates/nitrites and PDE-5 inhibitors?
Excessive hypotension
What do CCBs block?
L-type channels
What do CCBs cause in vascular SM?
Relaxation and vasodilation
What is a treatment for stable angina?
CCBs
Which drug is effective in preventing coronary vasospasm?
CCBs
What are the 2 types of CCBs? What are they used for?
Non-dihydropyridine (arrhythmias, cardiac effects)
Dihydropyridine (vasodilate arteries)
What drugs are non-dihydropyridine CCBs?
Verapamil
Diltiazem
What drugs are dihydropyridine CCBs?
“-dipines”
What CCB is used to treat angina pectoris?
Dihydropyridines
What CCB is used to treat arrhythmias?
Non-dihydropyridines
What happens when Ca2+ goes through a Ca2+ channel? (5 steps)
- Ca2+ enters cell
- Binds to calmodulin
- Ca2+-calmodulin complex activates MLC kinase
- Increase in myosin LC PO4
- Contraction
What kind of muscle gets Ca2+ externally?
Smooth muscle (internal organs)
What kind of muscle gets Ca2+ internally (from sarcoplasmic reticulum)?
Cardiac muscle
Skeletal muscle
What kind of muscle do CCBs block?
Smooth muscle
CCBs _________ coronary blood flow, myocardial perfusion, and O2 supply; CCBs ___________ myocardial O2 demand
increase; decrease
What is the mechanism of non-dihydropyridine CCBs?
Decrease contractility, HR, CO, & O2 demand
Increase diastolic relaxation of LV
What is an adverse effect of the CCB phenytoin? (ON EXAM)
Gingival hypertrophy
What do B blockers inhibit?
Sympathetic discharge and catecholamine release
What is the effect of B blockers?
Decrease contractility, HR, CO, & O2 demand
What do B blockers provide protection from?
Reflex tachycardia
What are the clinical uses of B blockers?
Angina pectoris
Prevent future myocardial infarctions
Which anti-anginal drugs are usually used together?
Nitrates + B blockers
(nitrates cause reflex tachycardia, B blockers inhibit reflex tachycardia)
What are the adverse effects of B blockers?
- Bronchoconstriction at high doses
- Decreases glucose in liver (risk of hypoglycemia)
- Myocardial depression/heart failure
- Chronic B blockade (B receptor super-sensitivity; slow withdrawal required
- CNS effects (depression, weakness, sleep disturbances, dizziness)
- Fatigue (from both cardiovascular and CNS effects)
What are the contraindications of B blockers?
Asthma
COPD
Variant angina
Why can’t B blockers be used in variant angina?
Can cause vasoconstriction
What is the opposing effect of high and low doses of epinephrine on vascular SM?
High dose: acts on a1 - vasoconstriction
Low dose: acts on B2 - vasodilation
What happens when epinephrine is given at a low dose and the pt is on a B blocker?
Vasodilation is inhibited
B blockers do NOT mix with what other anti-anginal drug?
Non-dihydropyridine CCBs
Why can’t you mix B blockers and non-dihydropyridine CCBs?
They both decrease HR and contractility
What can happen if you mix B blockers and non-dihydropyridine CCBs?
Intolerable dizziness
Increased risk of cardiovascular outcomes
Which drug is shown to increase the risk of stroke in elderly patients?
B blockers
T/F B blockers were removed from list of drugs of choice to treat hypertension in 2014
True
What are 2 second-line drugs to treat angina?
- Statins
- Anticoagulants
Which drug is an HMG-CoA reductase inhibitor used to prevent further progression of atherosclerosis?
Statins
Which drug is used to prevent blood clot formation in the coronary artery?
Anticoagulants
How often does nitroglycerin have to be replaced?
Every 3 months
Which patients cannot have nitroglycerin?
Those who have had PDE-5 inhibitors in the last 24 hours
What must you watch out for in the dental office when treating patients with cardiovascular disease?
Local anesthetics w/ epi
Retraction cords w/ epi