Anti-Arrhythmic Drugs 2 Flashcards
Esmolol
Class II
Selective Beta 1 adrenregic receptor blocker which leads to decreased HR, decrease AP in SA nodes, Decreased conduction velocity through AV node
Esmolol Recovers
Within 15 minutes after termination
Esmolol Excretion and Metabolism
Renal
Esmolol Cautions
Hypotension, compensated HF, bronchospastic, DM
Esmolol Contraindications
2nd and 3rd degree AV block
Severe HF
Cardiogenic shock
SA bradycardia
Amiodarone (Cordarone, Pacerone)
Class III Blocks K channels Blocks Na and Ca channels Blocks adrenergic receptors Structural analog of thyroid hormone Highly lipophilic
What all does Amiodarone do?
Inhibits abnormal automaticity Prolongs AP duration Prolongs PR, QRS and QT Causes sinus bradycardia Prolongs refractory period Inhibits cell-cell coupling
Amiodarone Elimination and Metabolism
Hepatic
CYP3A4
SUPER LONG HALF LIFE
Amiodarone AE
Pulmonary fibrosis Corneal microdeposits Hepatotoxicity Peripheral neuropathy and muscle weakness Proarrhythmic Thyroid dysfunction QT PROLONGATION Bradycardia Photosensitivity
Amiodarone Caution
Optic neuropathy
Respiratory distress syndrome
Pre-existing QT prolongation
Amiodarone Contraindications
2nd and 3rd degree AV block
Severe SA node dysfunction
Syncope
Dronedarone (Multaq)
Analog amiodarone Targets same as amiodarone Anti-adrenergic properties LESS THYROID effects Simpler kinetics (less lipophilic)
Dronedarone Elimination and Metabolism
Hepatic
CYP3A4
Shorter half life than amiodarone
Dronedarone AE
Bradycardia MODERATE QT PROLONGATION Worsening HF Asthenic conditions Skin conditions N/D/abdominal pain Increase SCr
Dronedarone Cautions
Patients with HF, sever hepatic impairment, electrolyte disturbances (K)
Increased level of digoxin
Amiodarone vs Dronedarone
A: used to maintain a normal sinus rhythm (rate control) in pts with afib
D: Increases mortality in those pts
Dofetilide (Tikosyn)
Potent and pure K channel blocker (increases duration of AP and refractory periods in atria and ventricles)
Dofetilide Elimination and Metabolism
H/R (mostly urine)
CYP3A4
Dofetilide AE
PROLONGS QT INTERVAL (torsade de pointes)
Headache, angina, dizziness
Dofetilide Cautions
Must start under close EKG monitoring
Other QTc prolongaters
Renal impairment
K-depleting diuretics
Dofetilide Contraindications
Prolong QTc
Severe renal impairment
What drugs cannot be used with Dofetilide?
Verapamil Cimetidine Trimethoprim Ketoconazole HCTZ
Sotalol (Betapace)
Inhibit K channels (160 mg) and increase duration of AP
Blocks beta 1/2 (25 mg)
Sotalol elimination
Renal
Sotalol AE
Pro-arrhythmic effects (torsades)
May mask hypoglycemia induced tachycardia in DM
Bradycardia, dyspnea and fatigue
Bronchospasms
Sotalol Cautions
Must be started under close EKG monitoring PROLONG QT HF Renal Impairment Hypokalemia and hypomagnesium
Sotalol Contraindications
2nd or 3rd degree AV block Prolong QTc Bradycardia Cardiogenic Shock Uncontrolled HF HYPOKALEMIA (less than 3.5)
Ibutilide (Corvert)
Inhibits K channels and increases duration of AP
PROLONGS QTc via activation of slow Na channels
Ibutilide Elimination and Metabolism
H/R
Metabolism unknown
Ibutilide AE
Torsades Hypotension Postural hypotension Bradycardia HF
Ibutilide Caution
Must be under close EKG
Prolong QTc drugs
Heart block
Ibutilide Contraindication
History of polymorphic VT (torsades, prolong QTc)
Digoxin MOA
Inhibition of Na K ATPase
Digoxin Main effects
+ Inotropic
Increased vagal tone and decrease sypathetic activity
Increase AV refractory period and decreased AV conductance
Digoxin Ion and Cardiac glycoside Actions
Hypokalemia- potentiates digoxin
Hyperkalemia- attenuates digoxin
Digoxine Cautions
Absorption is inhibited by antacids and BAS
Renal impairment
Combo with diuretics bc of hypokalemia
Combo with diltiazem and verapamil
