CH 35, 36, 37: Antianginals, HF, and Antiarrhythmics Flashcards
Pathophysiology of HF: what are the locations and types of HF?
location:
- left-sided: pulmonary edema
- right-sided: peripheral edema
types of failure:
- systolic failure: decr contractility, decr EF
- diastolic: decr ventricular filling, normal EF
What are cardiac glycosides used for?
- used in treating HF before ACEIs (ACEIs now first-line treatment)
- incr force of myocardial contraction –> incr contractility
- improves symptoms but doesn’t improve mortality
- stabilizes cardiac conduction abnormalities (watch with other antiarrhythmics)
- digitalization - incr dose gradually until tissues become saturated with medication and s/s of HF diminish
what are the considerations with HF?
- ensure pt monitors for dependent BLE edema
- worsening SOB or new onset of SOB
- evaluate # of pillows needed to sleep at night or if they are sleeping in recliner
- weigh themselves everyday - same time, scale, clothes
**- call HCP if 2lb weight gain in 1 day, or 5lbs in 2-3 days **
what are ARNIs?
**= ARB + neprolysing agents **
- decrease mortality by 40% –> will see massive improvement
what is the prototype drug for cardiac glycosides?
digoxin (Lanoxin, Lanoxicaps)
therapeutic: drug for HF
pharmacologic: cardiac glycoside, inotropic agent
digoxin - indications and mechanism of action?
indications: HF
mechanism of action: inhibits sodium-potassium-ATPase
- as sodium accumulates in myocytes, calcium ions are released from storage areas to activate contractile elements
what are the adverse effects of digoxin?
- general malaise
- dizziness, headaches
- N/V, anorexia
- visual disturbances (blurred or yellow vision)
what are the serious adverse effects of digoxin?
- ventricular dysrhythmias
- AV block (chambers stop talking to other chambers –> heart block)
- atrial dysrhythmias
- sinus bradycardia
What are organic nitrates used for?
short-acting, long-acting?
- to termine or prevent angina episodes
- short-acting: to stop angina attacks
- long-acting: to prevent angina attacks
organic nitrates: what is the mechanism of action?
- nitric oxide = cell-signaling molecule and potent vasodilator
- relaxes venous muscles –> redue preload = less work for heart
- ## relaxes arterial muscle –> incr blood flow to myocardium, heart doesn’t have to blow so hard = afterload reduced
organic nitrates: adverse effects?
- hypotension
- headache
- tolerance
prototype drug for organic nitrates?
indications too
nitroglycerin (Nitrstat, Nitro-Bid, Nitro-Dur, others)
therapeutic: antianginal
pharmacologic: organic nitrate, vasodilator
indications:
- acute angina/MI
- acute CHF/pulmonary edema
- severe HTN
- hypertensive emergency
nitroglycerin - what is the mechanism of action?
- forms nitric oxide @ vascular smooth muscle –> triggers cascade resulting in release of calcium ions
- relaxes both arterial and venous smooth muscles = less cardiac return (less preload & afterload)
-** dilates coronary arteries = incr O2 to myocardium (cardiac muscles)**
MI pharmacologic management
Beta-Adrenergic Blockers - what does it do?
- reduce myocardial demand
- decr HR (- chronotropic), decr contractility (- inotropic), decr BP
- counters effects of sympathetic stimulation
- reduce contraction + strength of contractility (prevents dysrhythmias)
- therapy usually continued for life
MI pharmacologic management
Angiotensin-converting enzyme (ACE) inhibitors - what does it do?
when to use, what to watch for
- given within 24h of onset of MI
- prevents cardiac remodelling
- suppress dysrhythmias
- therapy usually continued for life
- watch K+ levels and for angioedema
- check labs for K+ & renal function
MI pharmacologic management
Aspirin - what is for?
dosage?
- 160-325 mg initially, and then 81mg daily
- lower dose causes less GI bleeding
- heparin and low-molecular-weight heparins (enoxaparin) used for acute treatment
MI pharmacologic management
Thrombolitics: what are they used for?
timing? risks?
- to dissolve active clots
- only for use in early MI (best within 30 mins, no benefit after 24h)
- severe risk of bleeding
- alteplase (Activase)
MI pharmacologic management
what is used to preevnt and treat MI + thrombotic stroke? any others?
- clopidogrel (Plavix) and ticlopidine (Ticlid) used to prevent + treat MI & thrombotic stroke
- GP IIb/IIa inhibitors used for MI + pts undergoing percutaneous coronary interventions (PCIs)
- protease-activated receptor-I-antagonists, such as vorapaxar (Zontivity) = newly approved antiplatelet drugs used to reduce incidence of thrombotic events in pts with MI hx or clotting disorders
