Cardiac Pharm Flashcards
How long does it take an electrical impulse to travel through the heart?
Total time for the electrical impulse to travel through the heart is 0.22sec
SA Node (pacemaker)
- Automaticity?
- influenced by?
SA Node (pacemaker)
- Automaticity: 60-100 bpm
- influenced by: Sympathetic and Parasympathetic NS
AV Node
Automaticity?
Purpose?
AV Node (automaticity, but slower - 40-60bbm)
*allows the atria to completely empty into ventricles, optimizing cardiac output.
Class I – Sodium Channel Blocker
Drug?
Action?
Side Effects?
procainamide
Blocks sodium channels to prevent depolarization.
Slows impulse conduction across myocardium.
Prolongs refractory period.
anticholinergic effects (mental status changes, dry mouth, urinary retention)
*not used as much, can cause dysrhythmias
Class II – Beta Adrenergic Blockers
Drug?
Action?
Side Effects?
-lol s
SLOW DOWN! Widely used in treating CV disorders (HTN, MI, HF)
Affects the autonomic nervous system, decreases conduction velocity through AV node.
Treats atrial dysrhythmias associated with HF, decrease the likelihood of sudden death post MI
SE: bradycardia, hypotension.
Beta2 also affects the lungs -can produce bronchospasm (caution w/ asthma, COPD).
Don’t stop abruptly as this can cause rebound HTN and dysrhythmias
Class III – potassium channel blockers
Drug?
Action?
Side Effects?
Monitor?
amiodarone, sotalol
Delay repolarization of myocardial cells and lengthen refractory period
Multiple actions as they also affect adrenergic receptors and sodium channels.
Reserved for serious dysrhythmias both atrial and ventricular.
SE: bradycardia, hypotension, pulmonary toxicity and liver toxicity. SIDE EFFECTS LIMIT USE
MONITOR BP AND PULSE
Class IV – calcium channel blockers
Drug?
Action?
Side Effects?
Monitor?
diltiazem, verapamil
Specifically target the heart and arterioles.
Reduces automaticity of the SA node, slows impulse conduction thru the AV node, slowing HR and prolonging refractory period
ONLY useful in SUPRAventricular dysrhythmias
SE: similar to beta blockers so caution in patients taking drugs from different classifications.
MONITOR BP AND PULSE
Adenosine
Admin?
Action?
Treats?
Given as a 1-2 sec bolus
Terminates atrial tachycardia by slowing conduction thru the AV node and decreasing automaticity of SA node.
Primarily used in paroxysmal supraventricular tachycardia (PSVT)
Digoxin
Action?
Drug Class?
SE?
Antidote?
Decreases automaticity of SA and slows conduction thru the AV node.
Cardioglycocide
SE: Caution toxicity, check Dig levels, norm is 1.8ng/mL. Toxic effects include dysrhythmias esp in setting of hypokalemia. N/V, fatigue, visual disturbance (green-yellow halo or blurring). HOLD for toxicity.
Digoxin immune fab (Digibind) given for toxicity.
Nitrates
Action?
Relax smooth muscle, vasodilitation, decreasing oxygen demand on heart.
Nitroglycerin
SL Dose and Freq?
Patch Dose and Freq?
IV?
SL (0.3-0.6mg) 1 tab every 3-5 min, max 3 doses in 15 min
Transdermal patch every 24hr, on for 12hr, off for 12hr
IV – start at 5mcg and titrate for relief &/or BP control
Nitrate Side Effects?
Use caution with?
Special considerations?
SE: Headaches, hypotension, reflex tachycardia (sec to dilatation effect).
Caution use with sildenafil (Viagra) and like meds as severe hypotension and CV collapse can occur. Caution with ETOH.
Caution nitrate tolerance. Light sensitive, dark bottles, cover IV bag.
Beta Blockers for angina and MI
Treat?
Examples?
Cardioselective = Beta 1
Treat HTN and angina!
Atenolol (Tenormin)
Nadolol (Corgard)
Calcium Channel Blockers
Action?
Examples?
Special Considerations
Relax arterioles to reduce BP, some are also cardioselective (slow conduction)
CCBs treat vasospastic angina
Diltiazem (Cardizem)
Verapamil (Calan)
Nifedipine (Procardia)
Long and short acting
Instruct patients to not eat/drink grapefruit juice with po medication as this may increase the absorption
Thrombolytics
Reteplase (Reavase)
Action?
Admin?
SE?
Cleaves plasminogen to form plasmin which degrades the fibrin matrix of the clot.
IV bolus as soon as possible after onset of MI symptoms. May repeat bolus 30 min after 1st.
Most effective when administered 20 min -12hr of onset of symptoms
If Percutaneous Coronary Intervention (PCI) is not available within 1-2hr of admission, thrombolytics should be given within
SE: Bleeding!!!!
