Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Pharmacology > Anti-Anginal Drugs > Flashcards

Anti-Anginal Drugs Flashcards

1
Q

How can the heart return to balance in angina? (two ways)

A
  1. decrease O2 demand

2. Increase O2 supply

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What types of drugs decrease O2 demand?

A
  • beta blockers decrease heart rate and contractility
  • some calcium channel blockers can also reduce HR and contractility
  • nitrates and calcium channel blockers can dilate veins to reduce venous return, reduce preload and after load
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What types of drugs increase O2 supply?

A
  • dilate coronary blood vessels using vasodilators (calcium channel blockers), statins, and antithrombotics
  • myocardial vascularization (bypass or angioplasty)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What does ischemia affect?

A
  • affects ATP production and contractile function, which decrease CO
  • heart can’t tolerate O2 debt like skeletal muscle
  • ST segment depressed, T wave inverted
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Preload?

A
  • EDV
  • determines end diastolic fiber length and tension
  • venodilators decrease preload
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Afterload?

A
  • resistance heart must over come
  • determines systolic fiber length and tension
  • depends on arterial BP and stiffness
  • ateriodilators decrease after load
  • determined by PR, HR, contractility, ejection time (stronger contraction equals shorter ejection time)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What determines coronary blood flow?

A
  • coronary perfusion pressure (aortic diastolic pressure) and duration of diastole
  • inversely proportional to coronary vascular bed resistance
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Factors that influence coronary vascular bed resistance?

A
  • local metabolic products (decrease O2, increased H+, lactate, adenosine causes more dilation)
  • endothelial factors (nitric oxide causes more dilation)
  • autonomic activity
  • pharmocologic agents (calcium channel blockers, nitrates)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the most potent vasodilator?

A
  • ischemia- local metabolites accumulate causing a traffic jam, cannot increase blood supply to resolve imbalance
  • vasospastic coronary vessels can be relaxed and dilated, can open collaterals
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the problem with atherosclerotic vessels?

A
  • do not dilate like normal vessels
  • short acting vasodilators (dipyridamole, adenosine) may cause coronary steal effect (less dilation in ischemic areas, blood flows to normal areas)
  • can induce angina
  • dont use dipyridamole or adenosine for patients with CHD, can be used to diagnose CHD (stress test)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Types of Angina? Treatments?

A
  1. Fixed, stable
    - precipitated by exercise (O2 demand increase)
    - caused by obstruction of coronary arteries, atherosclerosis
    - relieved by rest
    - treat with nitrates, calcium blocker, beta blocker
  2. Variant, prinzmetals
    - occurs at rest or during sleep, unpredictable
    - caused by vasospasm or injured coronary artery
    - treat with nitrates, calcium channel blocker
  3. Unstable
    - increase in frequency or severity of anginal attacks
    - caused by combo of atherosclerosis, thrombosis, vasospasm
    - treat with angioplasty, nitrates, beta blocker, anti platelet
  4. silent ischemia
    - ischemia of myocardium without pain or symptoms
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Mechanism of action of nitrates?

A
  1. get into blood vessel and release nitric oxide
  2. NO is activated by Guanylyl cyclase
  3. increase in cGMP
  4. cGMP dephosphorylates myosin light chain
  5. actin and myosin dissociates
  6. smooth muscle relaxes, vessel dilates
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Why can’t sildenafil (viagra) be used with nitrates?

A
  • phosphodiesterease degrades cGMP to GMP
  • viagra blocks phosphodiesterase which leads to an accumulation of too much cGMP
  • this causes more relaxed blood vessels and more vasodilation
  • could lead to severe hypotension
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Nitrate effects?

A
  • vasodilation: veins > arteries > arterioles
  • preload reduced due to dilation of veins
  • afterload reduced due to dilation of arterioles at high doses
  • relieves vasospasm in variant angina
  • increases collateral flow to ischemic areas
  • decreases platelet aggregation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Nitroglycerin?

A
  • nitrate
  • rapidly acting, takes effect in 2 minutes, terminates acute attack
  • administer sublingual or spray
  • short duration, lasts 25 mins
  • avoids first pass effect
  • give to patient suspected of angina
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Isosorbide dinitrate?

A
  • nitrate
  • administer sublingual
  • takes effect in 5 mins, lasts 1 hour
  • use to terminate acute angina attack
17
Q

Amyl Nitrite?

A
  • rapidly acting
  • give to patient for acute angina attack
  • inhalation
18
Q

Prolonged nitrates used for angina?

A

-take orally and topically

  1. nitroglycerin ointment
  2. oral, sustained release nitroglycerin
  3. nitroglycerin transdermal patch
  4. Isosorbide dinitrate take orally once per day
  5. Isosorbide mononitrate
19
Q

When to use nitrates?

A
  • stable angina
  • variant angina
  • unstable angina
  • acute angina attack
20
Q

Monday disease?

A
  • must have a nitrate free interval that lasts at least 8 hours
  • adverse effects felt from nitrates, are gone quickly after person builds a tolerance
  • tolerance and rebound
21
Q

Adverse effects of nitrates?

A
  • excessive dilation, decrease BP, reflex tachycardia
  • headache (meningeal artery dilation)
  • potential severe hypotension with erectile dysfunction treatment (sildenafil)
22
Q

Mechanism of calcium channel blocker? effects?

A
  1. block L type calcium channel blocker to prevent influx of calcium in smooth muscle, cardiac nodal and muscle cells
  2. decrease in arteriolar tone, decreased after load
  3. relieve coronary artery spasm
  4. decrease HR and contractility
23
Q

Verapamil and Diltiazem?

A
  • non dihydropyridines
  • heart and blood vessels

Effects:

  • calcium channel blocker in heart and blood vessels
  • vasodilates vessels, decreases after load
  • decreases HR and AV node (verapamil)
  • decreases contractility of heart (verapamil), high doses or toxicity may cause CHF
  • Diltiazem reduces double product, prolongs exercise time

Clinical use:

  • relieves variant and stable angina, don’t use for unstable
  • use for fast atrial/nodal arrhythmias to slow HR/AV

ADR:

  • heart failure
  • AV blockade
  • sinus node depression
24
Q

Nifedipine?

A
  • dihydropyridines
  • calcium channel blocker in blood vessels, not heart

Effects:

  • mainly dilates arterioles
  • less cardiac depression

Clinical use:
-use for stable and variant anginas

ADR:
-reflex tachycardia due to excessive vasodilation

other drugs:

  • amlodipine
  • nicardipine
25
Q

Beta blockers mechanism for angina?

A
  1. want to inhibit beta 1 receptors
    - use drugs that won’t vasodilate
    - reduced HR prolongs diastole and coronary perfusion time
    - blocks tachycardia reflex by nitrates and calcium blockers
    - reduce contractility
  2. effective for stable, silent, and unstable anginas
    - not effective for variant angina
    - avoid drugs with intrinsic sympathetomimetic activity (pinodolol)
    - caution when combined with calcium channel blocker due to additive cardiac depressant, use dihydropyridines (Nifedipine)
26
Q

What beta blockers should you not use to treat angina? what should you use?

A

USE

  1. Metoprolol
  2. Atenolol
    - selective beta 1 blockers, long acting

DO NOT USE

  1. Pindolol
    - has intrinsic sympathetomimetic activity
  2. Carvedilol, Labetalol, Nebivolol
    - these are vasodilators
  3. Verapamil, Diltiazem
    - non dihydropyridines that depress the heart
27
Q

Effects of Nitrates or Dihydropyridine alone? Effects of beta blocker or calcium channel blockers alone? Combination?

A

Nitrates, Dihydropyridines alone

  1. reflex increase in HR
  2. reflex increase in contractility
  3. decrease in arterial pressure, EDV, ejection time

Beta and calcium channel blockers alone

  1. increase in EDV
  2. increase in ejection time
  3. decreases in HR, arterial pressure, contractility

Combination
-decreases HR, BP, EDV, contractility, ejection time

Pharmacology (9 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions