Acute Cardiac Flashcards
Digoxin Mechanism of Action
Sodium-Potassium ATPase blocker leading to inhibition of SNS and decreases automacity of AV node
Digoxin indications
Atrial fibrillation and heart failure
Control ventricular rate in patients with prolonged atrial fibrillation
Digoxin Adverse Drug Effects
Arrhythmias
Nausea and vomiting
Yellow/green visual auras
Types of Vasodilators and Examples
Hydralazine Indications and Mechanism of Action
Acute antihypertensive (IV)
4th line agent for chronic HTN
Used in conjunction with nitrates as chronic therapy in HFrEF
Mechanism of action is unknown, somehow cause smooth muscle relaxation resulting in arteriolar vasodilation
Minoxidil Indications and Mechanism of Action
4th line agent for chronic HTN
Increases Potassium channel activity in smooth muscle leading to membrane hyperpolarization and relaxation and arteriolar vasodilation
Minoxidil Adverse Effects
Hair growth
Calcium Channel Blockers Indications
Angina
Coronary artery spasm
HTN
Supraventricular arrhythmia (action at AV node—Verapamil, Diltiazem)
**No benefit in heart failure**
Nitrates Mechanism of Action
Mostly venodilation, some arteriolar dilation in coronary beds
Causes arteriolar dilation in face (flushing)
Decreases preload and at higher doses afterload
Sodium Nitroprusside Indications
Drug of choice for HTN emergency
Acute decompensated HF
Decreases both preload and afterload
Central α2 agonists Adverse Effects
Sedation
Rebound HTN with abrupt discontinuation
Diuretic drug classes and examples
Classes of antiarrythmic agents
▪Class I—Na + channel blockers
▪Class II—Beta-adrenergic receptor blockers
▪Class III—K + channel blockers
▪Class IV-Ca 2+ channel blockers
Quinidine Mechanism of Action
Blocks transmitter release from the vagus nerve
Can increase conduction velocity through the AV node
Quinidine Adverse Effects
Nausea, light headedness, headache, tinitis
Drug interaction with dixogen can lead to toxicity, need to monitor K+
Procainamide Indications
Supraventricular and ventricular arrhythmias
Conversion of new onset Afib to NSR,
Decrease likelihood of re-entry arrhythmias in acute MI
Can be used for VT—but not preferred drug
**Avoid with hyperkalemia (toxicity)
Procainamide Adverse Effects
Reversible SLE with chronic use
Prolonged QT
Torsades de pointes
Lidocaine Mechanism of Action and Indications
Alters the ventricular action potential by blocking Na+ channels which causes Na+ channels to remain open or inactive longer.
Can shorten repolarization, but DOES NOT prolong QT interval
Indicaitons: emergency ventricular arrhythmias, VT and PVC in stable patients
Lidocaine Adverse Effects
▪Slurred speech, tinnitus, hearing impairment, seizures, muscle twitching
▪Altered mental status, confusion
▪Blurred vision
▪Heart blocks
▪Altered AV conduction
Mexiletine Mechanism of Action and Indications
Blocks Na+ channels thereby altering ventricular action potential
DOES NOT prolong QT interval and it lacks vagolytic side effects
Indications: emergency ventricular arrhythmias
Mexiletine Adverse Effects
Nausea and tremor
Take with food to reduce side effects
Flecainide Indications and Contraindications
Indications: SVT, Atrial fibrillationn, PVC
Contraindications: structural heart disease and post MI
Should only be given to patients with normal EF
Flecainide Adverse Effects
Dizziness, headache, visual distrubance
Propafenone Mechanism of Action and Indications
Sodium channel blocker (most potent) with weak beta blocking activity
Indications: SVT, Atrial fibrillation, PVC
Should only be given to patients with normal EF
Propafenone Adverse Effects
Dizziness, disturbance in taste
Beta 1 vs Beta 2 receptors
Beta Blockers Adverse Effects
Hypotension
Bradycardia
AV block
Suppress hypoglycemia symptoms
First Generation Beta Blockers
Propranolol
Nonselective: Beta 1 and Beta 2
Second Generation Beta Blockers
Atenolol, Metoprolol
Relatively selective for Beta 1
Third Generation Beta Blockers
Labetolol, Carvedilol
Selective for Beta 1
Also cause vasodilation
Potassium Channel Blockers Examples
Amiodarone, Ibutelide, Dofetilide, Sotalol
Ibutelide Indications and Adverse Effect
Indications: atrial fibrillation and flutter
Adverse Effect: Prolonged QT–> Torsades de Pointes
Do NOT give to patients with pre-existing prolonged QT
Dofetilide Indications and Adverse Effects
Indicated only in Afib or Aflutter to NSR, can be used with depressed EF
Adverse effects: prolonged QT–> torsades de pointes
Sotalol Mechanism of Action and Indications
Mixed class II and III
▪Non-selectively antagonizes β-receptors (Class II action)
▪Blocks K+ channels (Class III action)
Indications: atrial fibrillation/flutter, severe ventricular arrhythmias