Arrythmias Flashcards
What is the most common arrythmia
Atrial fibrillation
How can AF be classified
first detected episode
paroxysmal
persistent
permanent
What is meant by paroxysmal AF
when a patient has 2 or more episodes of AF
and if they terminate spontaneously
episodes last less than 7 days - usually <24hrs
What is meant by persistent AF
if 2 or more episodes of AF
not self-terminating
episodes last greater than 7 days
What is meant by permanent AF
continuous AF
which cannot be cardioverted
What may someone with AF present with
patients may be asymptomatic
palpitations
dyspnoea
chest pain
irregularly irregular pulse
breathlessness
What investigations are required
first line ECG
FBC
Echocardiogram
What is AF characterised by
very rapid and uncoordinated atrial activity leading to irregularly irregular rhythm
What is the epidemiology of AF
commonest cardiac rhythm disorder
ageing is massive risk factor
What are causes of atrial fibrillation
ATRIALE-PIBI
alcohol and caffeine
thyrotoxicosis
rheumatic fever and mitral valve disease
ischaemic heart disease
atrial myxoma
lungs
electrolyte disturbances
pharmacological
iatrogenic
blood pressure
infections
How do you manage AF if the patient is hemodynamically unstable
cardioversion
If patient with AF is hemodynamically stable the how do you manage them
rate or rhythm control
How you manage rate control of a patient with AF
Beta blocker
if doesnt work combination of any 2 :
beta blocker
digoxin
diltiazem (CCB)
How do you manage rhythm control in a a patient with AF
beta blocker
Amiodarone
Flecainide - if no structural heart disease
What drug should not be offered to patients with AF
aspirin monotherapy
- for stroke prevention
What should patients with AF for less than 48 hours be treated with
anticoagulated with heparin
can be cardioverted electrically or pharmacologically
- using flecainide if no SHD or amiodarone if present
How should patients with AF for more than 48 hours be treated
delay cardioversion until they have been maintained on therapeutic anticoagulation for minimum of 3 weeks
during this period offer rate control
What should rate control therapy be offered as
as first line strategy
UNLESS
-reversible cause
-new onset AF
-heart failure is present
-rhythm control is more appropriate
When is rhythm control for AF usually preferred
if patients have concomitant heart failure or in younger patients
When may electrophysiological therapy be offered
radiofrequency ablation may be offered in intractable cases of AF that do not respond to medical therapy
What is the CHA2DS2Vasc score
used to assess risk of stroke
C- history of congestive heart failure (1)
H- hypertension (1)
A-age 65-74(1), >75 (2)
D-diabetes
S-stroke, venous thromboembolism (2)
S- female ( 1)
Vasc- vascular disease(1)
How do you interpret the CHA2D2Vasc score
score of 0 in men or 1 in women , recommend no anticoagulation
score of >1 in men , consider anticoagulation
score of >2 , offer anticoagulation
What is the HAS-BLED score for
used to assess risk of bleeding if on therapy
H- hypertension SBP>160 (1)
A- abnormal liver/renal function (1 point each )
S- stroke history (1)
B-bleeding history /predisposition (1)
L- labile INR (1)
E-elderly >65
D -drugs ( NSAIDs, antiplatelets) OR alcohol (1)
How do you interpret the HAS-BLED score
score =>3 does not preclude anticoagulation but caution is warranted , with regular review
What DOAC should be considered after CHA2DS2Vasc score has been calculated if needed
Apizaban , dabagatran, edoxaban or rivaroxaban
warfarin if DOAC is contraindicated or not tolerated
What is supraventricular tachycardia
refers to paroxysmal episodes of tachycardia that are not ventricular in origin
What is the aetiology of supraventricular tachycardia
caused by re-entry mechanisms , or impulse initiation disorders producing automatic tachycardias
What is the difference between AVNRT AND AVRT and what type of tachycardias are they
Re-entrant tachycardias
AVNRT - is caused by a non-anatomical pathway involving dual pathways with fast and slow conduction velocities
AVRT- caused by an anatomically defined re-entrant circuit involving one or more accessory pathways
What are the 2 types of automatic tachycardias
Junctional tachycardia- secondary to abnormal impulses from junctional region
Atrial tachycardia- tachycardia that is initiated and maintained irrespective of SA node, AV junction, accessory pathway or ventricular tissue
What is the acute management for SVT
first assess haemodynamic stability - if unstable arrange urgent direct cardioversion
Vagal maneuvers-
Valsalva - blow into empty plastic syringe
carotid sinus massage
IV ADENOSINE
rapid IV bolus of 6mg -
if unsuccessful go up to 12 , then 18
What drugs are given to a patient with SVT to prevent further episodes
beta-blockers
RFA
What is ventricular tachycardia
tachyarrhythmia that originates from the ventricles-
producing 3 or more successive broad QRS complexes at rate of greater than 100bpm
What is the aetiology of ventricular tachycardias
Ischemic heart disease
structural heart disease
electrolyte abnormalities
medications - digoxin toxicity
What is the management for ventricular tachycardia
if patient is hemodynamically unstable -
immediate resuscitation
emergency direct cardioversion
if patient is stable -
Amiodarone
lidocaine
procainamide
What drug should not be used in ventricular tachycardia
verapamil
What drug to treat ventricular tachycardia should be used with caution
Lidocaine - if patient has severe left ventricular impairment
If drug therapy fails how should a patient with ventricular tachycardia be managed
electrophysiological study
ICD- implantable cardioverter-defibrillator
What is torsades de pointes and how should it be managed
form of polymorphic VT associated with prolonged QT interval
IV magnesium sulphate
