Therapeutics: Arrhythmia 2

  1. What is the clearance for Dofetilide(III)?
    80% renal; 20% CYP 3A4
  2. What is the clearance for Ibutilide(III)?
    90% hepatic; 10% renal
  3. What is the clearance for Sotalol (III)?
    80-90% renal
  4. What is the clearance for Dronedarone (III)?
    100% hepatic CYP 3A4
  5. What is the t1/2 for amiodarone (III)?
    53 days
  6. What is the t1/2 for Dofetilide(III)?
    10 hrs
  7. What is the t1/2 for Ibutilide(III)?
    6 hrs
  8. What is the t1/2 for Sotalol (III)?
    8-18 hrs
  9. What is the t1/2 for Dronedarone (III)?
    13-19 hrs
  10. Which is the most cardiotoxic drug class of antiarrhythmics?
    • Class 1A
    • Worsen HF and can cause torsades
  11. Which antiarrhythmics are “cardiac neutral”, causing few cardiac side effects?
    Lidocaine and Mexiletine
  12. Why is Mexiletine a last resort medication?
    • High CNS side effects
    • Not well tolerated
  13. What are the cardiac side effects of Flecanide, and Propafenone (Class 1C)?
    • Worsen HF
    • Cause HB
    • Proarrhythmic (low incidence of torsade) but cause monomorphic ventricular tachycardia
  14. Of the class III drugs, which ones are more proarrhythmic?
    Dofetilide ,ibutilide and sotolol
  15. Of the class III drugs, which ones are less proarrhythmic?
    • Amiodarone and Sotolol
    • (Be careful when using them with other QT prolonging drugs)
  16. Which Class III drugs are Cardiac neutral?
    Amiodarone and Dofetilide
  17. Which Class III drugs are safe to use in patients having HF or underlying structural heart disease?
    Amiodarone and Dofetilide
  18. Which Class III drug is absolutely CI in patients having HF or underlying structural heart disease?
    • Sotolol
    • (don’t use flecanide or propanfenone either, though)
  19. Why should you not use verapamil or diltilazem in patients that have SHF?
    Can lower BP, reduce HR and cause heart block
  20. What is the most used/valued class?
    III
  21. Is it normal to see a QT interval >500 for Amiodarone?
    No, but still very very low torsades profile
  22. Which Class III antiarrhythmics have a profound reduction in HR?
    • Amiodarone and sotolol
    • Because of BB activity
  23. Why do Amiodarone and Sotolol have heart blocking capabilities?
    BB blockers
  24. What does it mean to be cardiac neural?
    • Does not worsen mortality
    • Safer in HF or structural Heart changes
  25. What are the side effects of Quinidine?
    GI (diarrhea), N/V, cinchonism (tinnitus, headache, nausea, blurred vision, psychosis, delirium), hepatotoxicity, drug fever, thrombocytopenia, hemolytic anemia
  26. What are the side effects of Procainamide?
    Neutropenia, drug-induced lupus, (up to 50% DC rate), GI
  27. What are the side effects of Disopyramide?
    Anticholinergic (urinary retention, dry mouth, blurred vision, constipation) - 70% of patients, hypoglycemia
  28. What are the side effects of Lidocaine?
    CNS
  29. What are the side effects of Mexiletine?
    CNS, GI, hepatotoxicity
  30. What are the side effects of Flecainide, Propafenone?
    CNS (dizziness, visual disturbances, headache), GI
  31. What are the side effects of Dofetilide, Ibutilide?
    CNS, GI
  32. What are the side effects of Sotalol?
    Beta-blocking effects
  33. What are the side effects of Dronedarone?
    ↑ Scr
  34. What are the GI side effects of Amiodarone?
    N/V (most common), constipation, weight gain, weight loss (anorexia)
  35. What are the CNS side effects of Amiodarone?
    headache, ataxia, insomnia or other sleep disturbances, malaise, fatigue, dizziness, paresthesia, abnormal smell, tremor, peripheral neuropathy, proximal myopathy
  36. What are the Pulmonary side effects of Amiodarone?
    • Pulmonary interstitial pneumonitis, hypersensitivity pneumonitis (both short lived)
    • Most catastrophic: Pulmonary Fibrosis (irreversible)
  37. What are the Dermatologic side effects of Amiodarone?
    Photosensitivity, blue-gray discoloration (reversible when D/C’d), hair loss, rash
  38. What do you do if an amiodarone patient presents with Pulmonary fibrosis?
    Stop Amiodarone
  39. How does Pulmonary fibrosis present?
    Fatigue, or flulike illness, blue-gray
  40. What is the most common oral Amiodarone side effect?
    N/V
  41. How long will amiodarone SE last?
    • 5-6 Half lives:
    • 1 year
  42. Why does Amiodarone cause Hyper or more commonly, Hypo thyroid?
    • 35% Iodine by Volume
    • Taken up into thyroid
  43. If a patient is on Levothyroxine and is receiving Amiodarone, what most likely should be done?
    Increase Levothyroxine ( high chance of Hypothyroidism)
  44. What are the Hematopoetic side effects of Amiodarone?
    Thrombocytopenia, spontaneous ecchymosis, coagulation abnormalities
  45. What are the Endocrine side effects of Amiodarone?
    Hyperthyroidism, hypothyroidism
  46. What are the Opthalamologic side effects of Amiodarone?
    Hyperthyroidism, hypothyroidism
  47. What are the Hepatic side effects of Amiodarone?
    Elevations in serum transaminases, hepatotoxicity
  48. What are the baseline tests that should be run when placing a patient on Amiodarone?
    PFT, CXR, Thyroid panel, Liver panel, ECG, Eye exam, CBC, BMP, Neurologic, Dermatologic
  49. What are the 3 month tests that should be run when placing a patient on Amiodarone?
    ECG, CBC, BMP, Neurologic, Dermatologic
  50. What are the 6 month tests that should be run when placing a patient on Amiodarone?
    Thyroid panel, Liver panel, ECG, CBC, BMP, Neurologic, Dermatologic
  51. What are the 12 month tests that should be run when placing a patient on Amiodarone?
    Thyroid panel, Liver panel, ECG, Eye exam, CBC, BMP, Neurologic, Dermatologic
  52. What test should be run on an amiodarone patient if they are symptomatic?
    • All:
    • PFT, CXR, Thyroid panel, Liver panel, ECG, Eye exam, CBC, BMP, Neurologic, Dermatologic
  53. Why does Amiodarone have lots of drug interactions?
    CYP3A4 inhibitor
  54. What are the CYP3A4 statins?
    lovastatin, simvastatin, and atorvastatin
  55. Which statin is most concerning when used with Amiodarone, why and what should be done?
    • Simvastatin, because it has a high risk of myalgias
    • No more than 20 mg dose with Amiodarone or switch to Crestor
  56. What drugs does Amioarone mainly interact with?
    • Warfarin
    • Digoxin
    • Penytoin and Phenobarbitol
    • Cyclosporine and Tacrolimus
    • Statins
  57. What are the consequences of Warfain and Amiodarone combo and how should you treat this?
    • Warfarin metabolism inhibited
    • Increased: PT, INR and bleeding risk
    • Treatment: Reduce warfarin dose by 25-50%; titrate to desired INR
  58. What are the consequences of Digoxin and Amiodarone combo?
    • Digoxin concentration increased by unknown mechanism
    • effect including sinus arrest, AV block, GI and neurological toxicity
    • Treatment: Reduce digoxin by 25-50%; titrate to therapeutic digoxin level
  59. What are the consequences of Cyclosporine or Tacrolimus and Amiodarone combo?
    • Cyclosporine/tacrolimus levels increase due to 50% reduction in clearance
    • Treatment: Monitor plasma concentrations with dosage adjustment
  60. What are the consequences of Phenytoin or Phenobarbitol and Amiodarone combo?
    • Increased concentration of phenytoin and phenobarbital
    • Increased neurologic toxicity
    • Treatment: Monitor plasma concentrations with dosage adjustment
  61. What are the consequences of Statin and Amiodarone combo?
    • Statin metabolism inhibited, Increased risk of myopathy/myalgia
    • Treatment: Avoid doses of statins when on amiodarone (no more than lovastatin 40 mg, simvastatin 20 mg, and atorvastatin 10 mg)
Author
kyleannkelsey
ID
267587
Card Set
Therapeutics: Arrhythmia 2
Description
Therapeutics: Arrhythmia 2
Updated