CVS - clinical management of AF Flashcards
What is arrhythmia?
Abnormal rate and/or rhythm of heartbeat
Too fast (TACHYcardia), too slow (BRADYcardia) or irregular
What range is heart rate is arrhythmia:
60-100 bpm
What are the common arrhythimas?
- Ectopic beats; electrical impulse can cancel the AV node and heart beat can skip a beat
- AF
- VT; venticular tachycardia
- VF; Ventricular fibrillation (life threatening)
What are the different types of AF?
Paroxysmal AF - episodes come and go
Persistent AF - each episode lasts for longer than seven days
Long-standing persistent AF - continuous AF for a year or longer
Permanent AF - present all the time
Symptoms of AF
Can be asymptomatic – especially in older people
Palpitations
Tiredness
Breathlessness/dyspnoea
Syncope/dizziness
Chest pain/discomfort
Is AF more common in men or women?
7% of those over 65, more common in women
more likely in those with other conditions; hypertension, atherosclerosis, heart valve issues
How does prognosis work?
not life threatening
Can cause heart failure as ventricles work too hard and enlarge > stroke
What are the goals of management?
establish the diagnosis of atrial fibrillation
control and prevent symptoms (by controlling ventricular rate or atrial rhythm)
prevent stroke
Treatment?
- admit if necessary (stroke or HF)
- rate control
- rhythm control
- stroke prevention
Example of beta blockers;
atenolol
acebutolol
metoprolol
nadolol
bisoprolol
adverse effects, bronchospasm, cold extremites, sleep disturbance, fatigure, sexual dysfunction
Rate-limiting calcium-channel blockers
verapamil and diltiazem
Digoxin monotherapy
in people with non-paroxysmal AF who are sedentary
Cardioversion - rhythm control
Recommended in some people with new-onset AF (within 48 hours of presentation), especially with reversible cause, in HF worsened by AF or with atrial flutter.
Carried out in specialist care
Pharmacological cardioversion
Electrical cardioversion (esp. if pt. has had AF for longer than 48 hours)
Surgical cardioversion
Flecainide (class Ic antiarrhythmic) - hwo to administer and s.e?
IV loaded then oral dosing
asthenia, dizziness, dyspnoea, fatigue, fever, oedema, pro-arrhythmic effects, visual disturbances, lots of drug interactions
Amiodarone (class III antiarrhythmic) DOSE?
200mg tds x7, bd x7, od
Adverse effects: bradycardia, hyperthyroidism, hypothyroidism, jaundice, nausea…
Catheter ablation - surgery:
normally carried out via a vein in the groin (sometimes wrist)
- area of heart causing abnormal electrical discharges destroyed with radiofrequency energy or cryotherapy
- if this is at the AV node, a pacemaker will be used in advance to restore sinus rhythm (“ablate and pace”)
stroke prevention; virchow’s triad
changes in vessel wall
changes in pattern of blood flow
changes in constituents of blood
Risk of stroke increases:
5x in non-rheumatic AF
17x in rheumatic (valvular) AF
More than 20% of strokes in the UK are attributable to AF
What do pharmacists do to score a risk of stroke?
stratification
Score 2 and above
Anticoagulation recommended
Score 1 and male
Consider anticoagulation
Score 0 (or 1 and female)
Anticoagulation not recommended
Do NOT offer antiplatelet drugs to anyone for stroke prevention in AF
More risk to male or women stroke
score 1 point for being female
if female scores 1 point - anticoagulant will not be given
e.g. score of 4
5.5% untreated»_space;» 1.7% treated
what is important to balance as well as stroke risk?
risk of bleeding (address reversible risk factors)
ORBIT
used to show risk;
sez
hemoglobin
age
bleeding hsitroy
GFR
treatment with antiplatelet agents
Direct-acting oral anticoagulants (DOACs)
Direct thrombin inhibitor – dabigatran
Direct factor Xa inhibitors – apixaban, edoxaban, rivaroxaban
Vitamin K antagonists
warfarin, acenocoumarol, phenindione
Which drug is more common to use than warfain now?
DOACs
standard dosing
No monitoring of INR req.
Number of interactiosn have been discovered - aware
Difficult to reverse effects
Dosing DOAC
- apixaban
- dabigartran
-edoxaban - rivaroxaban
Monitoring - patients taking DOAC
patients need to have bloods at least annually
All patients aged >75yrs (or if on dabigatran) need to be monitored 6-monthly.
Plus, patients need to be monitored according to CrCl:
What needs to be incl in an anual review?
Patient counselling:
Adherence – short half life so very important
Specific dosing advice – keep dabigatran in packet, rivaroxaban take with food
Missed doses – daily preps (riv, edox) take within 12 hours, bd (apix, dab) take within 6 hours
Monitoring – inform of
frequency and arrange
Alcohol – stay within limits
Bleeding – advise on signs and symptoms and emergency advice
OTC - avoid aspirin/NSAIDs, St John’s wort
Warning card – carry it and show it when receiving medical care
What is the most common adverse effect of wardarin?
bleeding
are warfarin effects reversible?
yes when using vit K
