Arrhythmias Flashcards
How are ectopic beats treated
rarely need treatment but could use beta blocker
if patient presents with arrythmia had less than 48 hours is rate or rhythm preferred?
rhythm control
-over 48 hours rate control
2 treatments for urgent rate control
beta blocker or verapamil IV
2 drugs for pharmacogolical cardioversion
flecinade amiodarone (preferred when there is structural heart disease)
Is pharmacological or electrical cardioversion preferred
electrical if arrhythmia present for over 48 hours - pt must be anticoagulated
Rate or rhythm control is first line
Rate (unless less than 48 hours or arrhythmia)
What beta blocker is not suitable for rate control
sotolol
what are two rate limiting CCBs?
verapamil and diltiazem
what are the two drug classed that are used for rate control
beta blocker
rate limiting CCB
does digioxin control rate or rhythm
when is it suitable and why
rate
predominately sedentary patients as it only controls rate at rest
(also used when there is AF and CHF)
what is first
second
third line for AF
first - rate monotherapy
second - two rate controlling medications
third - rhythm control
rhythm control options: (6)
betablocker or anti-arrhythmic drugs: -sotolol -flecinade -propanfenone -amiodarone -dronedarone
what is used for pil in the pocket (2)
flecinade
propafenone
chads vasc parameters:
Congestive heart failure/Left ventricular dysfunction (1) Hypertension (1) A2 - Age≥75 (2) Diabetes mellitus (1) S2 - Stroke/TIA/TE (thromboembolism) (2) Vascular disease — coronary artery disease (CAD), myocardial infarction (heart attack), peripheral artery disease (PAD), or aortic plaque (1) Age 65-74 (1) Sc - Sex category — Female gender (1)
hasbled parameters
Hypertension (1) Abnormal liver/renal (1 or 2) Stroke (1) Bleeding (1) Labile INR (1) Elderly (1) Drugs/alchohol (1)
Is aspirin a suitable alternative to anticoagulation in AF
no - ther risk of bleeding outweighs the modest benifit
what is a labile INR
in range less than 60% of the time
What systolic BP is considered hypertension in the HASBLED
> 160
How do you assess the need for anticoagulation in atrial flutter?
Using HASBLED and CHADSVASC just like AF
what would be the treatment for bradycardia post MI (2)
atropine IV
or adrenaline
what electrolyte imbalance can contribute to long QT syndrome?
hypokalaemia
what is dysopyramide used for? what is a caution with this drug?
control arrhythmias after MI
but has anticholinergic effects therefore caution in BPH and closed angle glaucoma
caution of flecainide
can precipitate serious ventricular arrhythmias in patients with otherwise normal hearts in a small minority of patients
What is the loading dose for amiodarone
200mg tds - one week
200mg bd - one week
200mg od - from then on
how long can drug interactions happen after treatment with amiodarone
weeks or even months after stopping treatment
How does amiodarone affect the QT interval
prolongation - caution with loads of drugs
what color can amiodarone discolour skin?
slate grey
what is the problem with amiodarone and driving at night?
is this reversible?
is this side-effect a reason to withdraw treatment?
microdiposits in the cornea - causing night glare (being dazzled when driving and night)
(reversible)
this does not usually impair vision however if vision is impaired treatment must be withdrawn to prevent bliness as this could be optic neuropathy
why would you be concerned about a patient on amiodarone with increasing SOB or cough
pulmonary toxicity - pneumonitis and fibrosis of the lungs
what blood tests should we be doing routinely with amiodarone treatment
TSH/T4
LFTs
every 6 months
what is the affect of amiodarone on the thyroid and why?
should amiodarone be withdrawn?
hyper or hypothyroidism can occur
contains iodine
withdraw at least temporarily to achieve control but can continue amiodarone while controlling if necessary
what is the effect of amiodarone on the liver
may effect LFTs but also may cause hepatotoxity
if tests severely deranged or symptomatic withdraw amiodoarone
what electrolyte should be monitored before amiodarone treatment
Potassium (there is no reason for this stated in the BNF but potassium is all about hearts so just remember that)
what advice would you give an amiodarone patient going on holiday to spain
PHOTOTOXICITY - SHIELD YOURSELF FROM THE SUNNNNNNNN!!!!!
can amiodarone tabs be crushed?
yes
what is the effect of amiodarone on the peripharies
may cans peripheral neuropathy
What two electrolyte imbalances MUST be corrected before treatment and why?
(this is a BNF warning box)
hypomagnesaemia
hypokalaemia
- because sotolol prolongs the QT interval and occationally may cause life threatening ventricular arrhythmias
for the management of AF digioxin should be taylored to pulse rate, but what pulse is too low
pulse should not be allowed to fall below 60bpm
what demographic is particularly suceptable to digioxin toxicity?
the elderly
What electrolyte disturbance predisposes a patient to digoxin toxicity?
how do we manage this?
hypokalaemia
- manages using K sparing diuretics or in necessary K supplementation
how does the dose of digioxin need to be changes when switching from IV to oral
20-33% increase to maintain same plasma conc
id monitoring plasma digoxin levels when would you take the blood?
6 hours post dose
plasma digoxin concentration alone dose not reliably indicate toxicity BUT liklihood of toxicity increases progressively through the range of …………. to …………..
1.5-3 MICROgrams/litre
what is the maintinance dose range of dig and how do you decide what to give?
125-250 micrograms OD - according to renal function
name some significant interactions with digoxin and how to manage
amiodarone increases plasma digoxin
half the digoxin dose
name some significant interactions with amiodarone
inhibitor of CYP therefore all of those interactions
what is the effect of amiodarone on warfarin
enhanced anticoagulant effect (by inhibiting the metabolism of warfarin)
is there an interaction between amiodarone and statins?
amiodarone increase risk of myopathy with simvastatin
is there an interaction with amiodarone and lithium
yes - both these drugs seem to interact with erverything so look out chaps
what CCBs can interact with beta blockers
diltizem and verapamil - AV block, bradycardia, HF
