5. Antiplatelets, NOAS & A-Fib

Question 1

When can you use prophylaxis for endocarditis reasons?

Answer 1

1. Prosthetic heart valves
2. Previous infective endocarditis
3. Cardiac transplant recipient who develop cardiac valvulopathy
4. Patients with congenital heart disease

Question 2

What makes up congenital heart disease?

Answer 2

• Unrepaired cyanotic CHD - palliative shunts
• Completely repaired congenital heart defect
• Repaired CHD with residual defects

Question 3

What procedures do not need prophylaxis?

Answer 3

• Anesthetic injections
• Radiographs
• Placement of pros or ortho removable appliances
• Ortho bands
• Shedding of deciduous teeth
• Bleeding from lips or oral mucosa

Question 4

What is the standard antibiotic prophylaxis for IE?

Answer 4

• Amoxicillin 2g orally
  
  • or Ampicillin 2g IM or IV
• Allergic to amox
  
  • Clindamycin 600mg orally or
  • Cephalexin 2 g orally or
  • Azithromycin/clarithromycin 500mg

Question 5

Why would a patient be on anticoagulants such as warfarin?

Answer 5

• Prosthetic heart valves
• Hx of deep venous thrombosis
• MI
• Stroke
• A-fib

Question 6

What is the most widely prescribed drugs in the US?

Answer 6

Warfarin

Question 7

What are the values you want to know with a patient on warfarin?

Answer 7

• Anticoagulation level
  
  • PT (prothrombin time)
  • INR
• PT - normal range = 11-13 sec (goal 16-20)
• INR - normal range = 1.0-1.3 (goal 2.5-4.5)

Question 8

What INR can routine dental care be perfomed at?

Answer 8

3.5 or below

Question 9

When should PT and INR be measured?

Answer 9

Within 24 hours. only a physician should make changes to pt’s anticoagulation therapy

Question 10

What are the issues with warfarin?

Answer 10

• Narrow therapeutic window
• Hemorrhage risk
• Frequent lab monitoring
• Multiple food and drug interactions

Question 11

What foods & drugs should be avoided with warfarin?

Answer 11

• Vitamin K (leafy greens)
• Cranberry juice (increase effect)
• Alcohol
• Aspirin, NSAIDS, Acetaminophen

Question 12

What antibiotic should be prescribed to a pt taking warfarin?

Answer 12

• Pen V or Clindamycin

Question 13

The literature does not support the long-held belief that an oral anticoagulant regimen must be altered or discontinued before most dental procedures (T/F)?

Answer 13

True

Question 14

What are the common anti-platelet agents and why are they used?

Answer 14

• Aspirin, Ticlid, Plavix
• Prophy for coronary thrombosis
• Prevention of adverse thromboembolic events

Question 15

What is A-fib?

Answer 15

Cardiac dysrhythmia

• Electrical impulses normally generated by the sinoatrial node replaced by disorganized & ineffective activity in atria
• Responsible for 15-20% of all strokes

Question 16

What do you commonly see A-fib with?

Answer 16

• Coronary artery disease
• Congestive heart failure
• Diabetes
• Thyrotoxicosis

Question 17

What are the common medications prescribed for A-fib?

Answer 17

• Amiodorone
  
  • But shouldn’t be prescribed with warfarin – increases anticoagulation

Question 18

What is Dabigatran?

Answer 18

• Approved to reduce risk of stroke and clots in patients with non-valvular a-fib
• And prevents venous thromboembolic events
• Eliminated by kidneys - not used in severe renal impairment

Question 19

Do you need a reversal agent for Dabigatran?

Answer 19

No- such a short half-life, just wait it out to resolve minor bleeding

Question 20

What clotting factors do the following work on:

• Rivaroxaban
• Apixaban
• Dabigatran

Answer 20

• Rivaroxaban - X
• Apixaban - X
• Dabigatran - II

Question 21

What is the newest FDA approved drug this year (Jan 8,2015) for stroke, a-fib and DVT?

Answer 21

Edoxaban (Savaysa)

Question 22

What is the standard of care for the management of patients with valvular A-fib or mechanical heart valves?

Answer 22

Warfarin