Arrhythmias and Anticoagulants Flashcards
What is an arrhythmia?
Refers to any change in the normal rate or rhythm of the heart
Why do arrhythmia occur?
- Altered impulse generation: changes in the automaticity of the pacemaker cells in the SAN
- Altered impulse conduction: complete / partial block of conduction pathways
What are the types of arrhythmia?
- Bradycardia
- Tachycardia
- Atrial Flutter
- Atrial Fibrillation
What are the symptoms of Atrial Fibrilation?
- Breathlessness
- Light headedness
- Fatigue
- Palpitations
- Chest Pain
What are class Ia. Ib and Ic drugs?
Na channel blockers
What are class II drugs?
Beta-adrenoreceptor blocker
What are class III drugs?
K+ channel blockers - prolongs action potential
What are class IV drugs?
Ca2+ channel blockers
What are the types of AF?
- Paroxysmal (termination within 7 days)
- Persistant (7 days+)
- Permanent (1 year+)
What is the first line strategy for AF patients?
Rhythm control
- Cardioversion
- Amiodarone therapy
Drug treatment
- Beta blocker
- Dronedarone
What are the adverse effects of amiodarone?
- Interstital pulmonary fibrosis
- GIT intolerance
- Tremor, dizziness
- Hyperthyroidism
- Liver toxicity
- Photosensitivity
- Neuropathy
- Blue skin discolouration
What is amiodarone?
It is a class III drug, delays phase 3 (repolarisation)
What is the normal INR?
1
What is the normal INR for AF patients?
2-3
What is the normal INR for patients with a mechanical heart valve?
2.5-3.5
What are the NON-Vitamin K antagonists (NOACS)?
Dabigatran - direct thrombin inhibitor
Rivaroxiban, apixaban and edoxaban acts an an inhibitor of factor Xa.
What drug would you use to reverse the anticoagulant effect of dabigatran?
Idanicizumb (Praxabind)
How do unfractionated heparins work?
Prevents production of fibrin from fibrinogen
What is Fondaparinux?
Direct antithrombin III and inhibits factor Xa
