AF and stroke Flashcards
who is AF common in?
age >55
what are the symptoms of AF?
breathlessness, palpitations, chest discomfort, fatigue, reduced exercise tolerance, dizziness
what is paroxysmal AF?
self-limiting episodes lasting no more than 7 days
what are the underlying causes of AF?
high BP, hyperthyroidism, heart valve disease, ischemic heart disease
what is suggestive of poor coagulation?
2 INR levels higher than 5 OR 1 INR level higher than 8 in the past 6 months
emergency treatment for acute AF life threatening headmodynamic disability?
emergency electrical cardioversion to achieve anticoagulation
emergency treatment for acute AF NOT life threatening?
give rate or rhythm control if onset is less than 48hr but if onset is more than 48hours or uncertain give rate control
what is pharmacological cardio version?
IV amiodarone or flecainide
rate control is preferred first line treatment except when…..
- AF is new onset
- Atrial flutter suitable for ablation strategy
- AF with reversible cause
- Rhythm control is more suitable
what drugs are used in the pill in the pocket strategy?
flecainide and propafenone
what 2 processes are involved in destruction of neuronal cells?
apoptosis - occurs within 1 hour
necrosis - occurs within 6 hours
initial management of stroke?
alteplase - within 4.5hrs
aspirin - 300mg for 14 days (start within 24hrs)
assess swallowing ability
long term anti-platelet management for stroke?
ischaemic stroke -clopidogrel 75md OD
TIA - MR dipyridamole 200mg BD AND aspirin 75mg OD
when is anticoagulant treatment given for stroke and TIA pts?
stroke - delay treatment for 2 weeks
TIA - start immediately
what are the 4 common underlying causes of AF?
high BP, ischaemic heart disease, heart valve disease, hyperthyroidism
what does the LVEF have to be before giving dabigatran and when can you give it to above 65+?
less than 40% and 65 or older with one of the following; DM, coronary artery disease, HTN
what can contribute to poor anti-coagulation control?
illness, interacting drugs, lifestyle factors, cognitive function
when would you consider left appendage atrial occlusion (LAAO)?
consider this if anti-coagulation is contraindicated or not tolerated
why would you not consider digoxin?
only if patient is sedentary as it doesnt work on exertion
what would be initial rate control monotherapy?
BB (other than sotalol) or CCB
who should you NOT offer flecainide and propafenone?
to people with known ischaemic or structural heart disease
who should the pill in the pocket strategy be considered for?
those who have no history of LVD, or valvular or ischaemic heart disease and have a hx of infrequent symptomatic episodes of paroxysmal AF and have a systolic blood pressure greater than 100 mmHg and a resting heart rate above 70 bpm and are able to understand how to, and when to, take the medication.
how would you reduce risk of postoperative AF?
amiodarone, standard beta blocker (not sotalol) and rate-limiting CCB
advantages of NOAC?
- efficacy and safety appear similar to warfarin
- rapid onset of action
- does NOT require INR monitoring
- fewer drug interactions
what is an embolic stroke?
blood clot that blocks the cerebral artery and originates outside the brain
what can TIA be defined as?
temporary episodes of cerebral ischaemia
what are the major symptoms of stroke?
FAST
how can some patients recover from the sensory deficits caused by stroke?
undamaged neurones sprout new branches into the damaged area and aid in the recovering lost function
how does hypoxia affection overreaction of glutamate and aspartate receptors?
hypoxia - over reaction of glutamate and asparate receptors, result in opening of certain receptors including NMDA - subsequent membrane depolarisation causes influx of Ca, Na and Cl ions and efflux of potassium ions. - Intracellular Ca increases proteases, lipases and endonucleases which causes destruction of cell structures.
the region affected by severe ischaemia is called?
core zone
the patient may find difficulties in speaking and understanding speech and may get confused between left and right. - which area of the brain is affected?
wernicke’s area of the cerebrum
how would you diagnose stroke/TIA?
Computerized tomography (CT), MRI (can detect changes within minutes)
what tool is used to commonly distinguish between ischaemic and hemorrhagic strokes?
CT
for initial management what should be considered for patients being transferred home before 14 days?
Patents who are transferred home before 14 days should switch from: asprin 300mg to clopidogrel 75mg
when should anticoagulation not be given for long term management of stroke?
in uncontrolled HTN or until brain imaging hasnt ruled out haemorrhagic stroke
what should be given to patients if pts have prev dyspepsia associated with aspirin
aspirin + PPI
in apoptosis what process occurs later?
breakdown of integrity of plasma and mitochondrial membrane
major causes of IDA?
inadaquate iron absorption, increased physiological demand, GI bleeding
treatment of IDA
ferrous sulphate 200mg BD/TDS - takes between 1-2 weeks for Hb level to rise - continue up to 3 months after levels return to normal to replenish stores
what should you give if ferrous sulphate is not tolerated?
ferrous gluconate, ferrous fumarate
parenteral iron options
IRON DEXTRAN,
IRON SUCROSE,
FERRIC CARBOXYMALTOSE,
IRON ISOMALTOSIDE
what serum ferritin levels confirms diagnosis?
less than 15mcg/L
why is the onset of b12 deficiency delayed?
Onset of anaemia is delayed because the body has 2-3mg of stores which is sufficient for 2-3 years
treatment for vitamin b12 defiency?
IM hydroxycobalamin 1mg 3 times a week for 2 weeks then 1mg every 3 months
where there is neurological involvement give 1mg on alternate days for 2 weeks then 1mg every 2 months
what is the cell size and cell colour in iron deficiency anaemia?
SMALL cell size and PALE colour
mechanism of bile acid sequestrants
hepatic conversion of cholesterol to bile acids
example of a fibrate
gemfibrozil
symptoms of b12 deficiency
Mild thrombocytopenia, spleen slightly enlarged, mild jaundice, slow insidious onset, progressive neuropathy affective legs – tingling in feet and loss of vibration sense (feature separating it from other anaemias)
what should you consider if pharmacological cardioversion is agreed?
A choice of flecainide or amiodarone to people with no evidence of structural or ischaemic heart disease or
amiodarone to people with evidence of structural heart disease.
In people with atrial fibrillation in whom the duration of the arrhythmia is greater than 48 hours or uncertain and considered for long‑term rhythm control, delay cardioversion until what?
they have been maintained on therapeutic anticoagulation for a minimum of 3 weeks. During this period offer rate control as appropriate.
when is dronedarone recommended?
option for the maintenance of sinus rhythm after successful cardioversion in people with paroxysmal or persistent atrial fibrillation
if drug treatment for long term rhythm control is needed what is recommended as first line?
beta blocker other than sotalol
if monotherapy with a standard beta blocker is not successful as a rate control strategy what would you recommend?
combination therapy with digoxin, diltiazem, beta blocker
which drug should you avoid in heart failure and LV dysfunction?
CCB and dronedarone
with anticoagulant for stroke prevention would you give if left ventricular ejection fraction below 40%?
dabigatran
