arrythmias Flashcards
AF vs ectopic beats
ectopic beats - spontaneous and rarely requires treatment
- if treatment needed - beta blocker
AF - can lead to complications such as stroke - as blood doesn’t eject - clots
- assessed and treated for stroke risk
- manage via rate or rhythm control
acute AF management
if life-threatening haemodynamic instability caused by AF:
- emergency electrical cardioversion without delay to prevent clot
no life-threatening haemodynamic instability:
- if onset of AF < 48 hrs - rate or rhythm control
- if onset > 48 hrs - RATE
if cardioversion (rhythm) agreed:
- pharmacological: flecainide or amiodarone
- electrical: start IV anticoagulation to rule out left atrial thrombus
AF maintenance
1st - rate control monotherapy
- standard BB (not sotalol)
- or RL CCB
- digoxin (in sedentary pt with non-paroxysaml AF)
2nd - rate control dual therapy
with BB, digoxin or diltiazem
3 - rhythm control
- pharmacological - flecainide or amiodarone
if AF present > 48hrs - electrical cardioversion preferred
- pt must be fully anticoagulated for at least 3 weeks
+
oral anticoagulant given for at least 4 weeks after cardioversion
drug treatment post cardiovert:
- standard beta blocker
- SPAF - sotalol, propafenone, amiodarone or flecainide
- amiodarone can be started 4 weeks before + continue for upto 12 months after cardioversion to increase success of procedure
avoid flecainide and propafenone in ischaemic heart disease
in LVEF - use amiodarone instead
dronedarone - 2nd line in paroxysmal/persistent AF
paroxysmal AF management
beta blocker
if symptoms persist - SPAF
if infrequent eps of symptomatic paroxysmal AF:
- pill in the pocket strategy
- takes oral flecainide or propafenone when required
stroke prevention
assess all patients for risk of stroke and need for thromboprophylaxis
CHADVASC for stroke risk
C - congestive HF - 1
H - hypertension - 1
A - age > 75 - 2
D - diabetes - 1
S - stroke/TIA - 2
V - vascular disease - 1
A - age 65-74 - 1
Sc - sex female - 1
max 9 points
thromboprophylaxis not needed in:
- MEN with score of 0
- WOMEN with score of 1
thromboprophylaxis - warfarin or in non valvular AF - DOACs
atrial flutter treatment
aim to treat with rate or rhythm control - but atrial flutter reacts less effectively to drugs
- electrical cardioversion is best
rate control - temporary till sinus rhythm restored - bb/rl CCB
rhythm control restored with:
- direct current cardioversion
- pharmacological cardioversion
- catheter ablation - recurrent atrial flutter
assess pt for stroke risk
ensure pt anticoagulated for 3 weeks if flutter lasted > 48 hrs
paroxysmal supraventricular tachycardia
1) treatment usually not needed - terminates spontaneously alone
2) reflex vagal stimulation
- valsalva manouevre (blow hard cover mouth/nose)
- immerse face in ice-cold water
- carotid sinus massage
3) IV adenosine
4) IV verapamil
treat recurrent symptoms with catheter ablation
prevent future eps with BB or RL CCBs
ventricular tachycardia treatment
pulseless ventricular tachcyardia or ventricular fibrillation - resuscitation
unstable ventricular tachycardia - DCC then IV amiodarone then repeat current cardioversion
stable ventricular tachycardia
- IV amiodarone - DCC
- unsustained - beta blocker
patients at high risk of cardiac arrest
- require maintenance therapy
- implantable cardioverter defibrillator
- beta blocker with amiodarone
torsades de pointes (QT prolongation) treatment
can be drug induced or caused by hypokalaemia or severe bradycardia
- amiodarone, sotalol, macrolides, haloperidol, SSRIs (citalopram), TCAs (amitriptyline), antifungals (azoles)
usually self limiting - but can be recurrent - leads to impaired consciousness - ventricular fibrillation - death
treat with IV magnesium sulfate
beta blockers (not sotalol)
DON’T USE anti-arrythmics - prolong QT interval - worsen condition
classification of anti-arrythmic drugs
class I - membrane stabilising drugs - lidocaine, flecainide
class II - beta blockers
class III - amiodarone, sotalol
class IV - RL CCBs verapamil, diltiazem
amiodarone imp points
loading dose - 200mg TDS for 7 days then 200mg BD 7 days then 200mg OD - maintenance
avoid in bradycardia and heart block
SE’s:
- corneal microdeposits - blurred/dazzled vision - if vision impaired - STOP
- thyroid dysfunction
can cause hypo/hyperthyroidism due to iodine content - photosensitivity
avoid UV exposure and use sunscreen months after treatment end - really long half-life
- hepatotoxicity
stop if pt shows signs of liver disease - pulmonary toxicity
progressive SOB and cough - driving and skilled tasks
microdeposits may impair vision
amiodarone interactions
very long half life - interactions after weeks/months
drugs that cause QT prolongation, hypokalaemia
amiodarone = cyp450 inhibitor
- other inhibitors and inducers
drugs that cause bradycardia
- bb, rl ccbs
amiodarone monitoring
TFTs - before and every 6 months
LFTs - before and every 6 months
serum Potassium conc. - before
chest x-ray - before
annual eye examination
IV use - ecg, liver transminases
digoxin imp points
digoxin - narrow therapeutic index
range 0.7 - 2 ng/mL
toxicity risk increases from 1.5 - 3 ng/ml
- treated with digoxin-specific antibody
bloods done 6-12hrs after dose
- monitor serum electrolytes + renal function
signs of toxicity: SICK + SLOW
- SA/AV block and bradycardia
- blurred and YELLOW vision
- diarrhoea and vomiting
- dizziness, confusion, depression
AF maintenance dose 125-250mcg OD
interactions:
- beta blockers - increase risk of AV block
- drugs that cause hypokalaemia - increase risk of digoxin toxicity
- TCAs - can induce arrythmias
- CYP inhibitors - increase conc
- CYP inducers - decrease conc
