Arrhythmias Flashcards
What is the Levine scale used for?
Grading murmurs
What level of the Levine scale is a thrill present with?
4-6
Adverse effects of amiodarone
Thyroid dysfunction - hyper/o
Pulmonary fibrosis/itis
Liver fibrosis, hepatitis
Peripheral neuropathy, myopathy
Photosensitivity
Thrombophlebitis and injection site reactions
Bradycardia
Prolonged QT interval
What is thrombophlebitis
Inflammation of a vein related to a blood clot - superficial version of DVT
How can amiodarone effect an ECG?
Prolonged QT interval, bradycardia
How does amiodarone effect warfarin?
Decreased metabolism -> increased INR
How does amiodarone affect digoxin?
Increased levels - more effects
What is the primary pacemaker of the heart
Sinoatrial node
What is chronotropic incompetence
HR fails to pick up w exercise
What is given to speed HR in emergencies
Atropine
What is given for long term control of sick sinus syndrome
Pacemaker
What is a supraventricular tachycardia
Where electrical signals from the heart get stuck in a short circuit and loop around AV node or elsewhere
How is SVT terminated
Vagal manouveres eg blowing on syringe
IV adenosine
IV verapamil
What drugs block the AV node
Adenosine
Treatment for SVT
Adenosine in emergency
Beta blockers, catheter ablation for recurrent
How does SVT -> ECG
Fast rhythm, often not visible p waves
What is an AV node re-entry tachycardia
Atrium and ventricles simulataneously depolarise
What is AF
V fast and disordered atrial activity
What is a VT
Fast regular rhythm form ventricels
ECG of VT
Broad QRS
P waves not seen or unrelated to QRS
Caause of VT
Cardiac ischaemia or MI scar
What to do if patient with VT haemodynamically compromised
Cardiovert
What to do if patient with VT haemodynamically stable
Amiodarone
What is VF
> 300BPM irregular rate
QRS variable morphology
TREAT - defib
6 questions for identifying arrhythmias
- Are there QRS complexes - asystole
- What is the rate of QRS - tachy or brady
- Are the QRS regular or irregular
- QRS narrow or broad - narrow = top chambers of heart/SVT. Broad - ventricles
- visible/ditinct P waves? PR interbal
- Relationship between P waves and QRS complexes
First line treatment for bradycardia w adverse signs
Atropine 500ug up to 3mg
What is atropine contraindiated in
Myasthenia gravis
Paralytic ileus
What is sick sinus syndrome
Failure of sinus node -> depolarisation intermittently
Bradycardia and tachycardias
Treatment sick sinus syndrome
Permanaent pacemarker if symptomatic
Antiarrhythmics - beta blockers
Anticoagulation - increased VTE risk
AVNRT on ECG
Normal QRS complexes
P waves cant be seen or just after or before QRS
Most common SVT and who seen in
AVNRT - twice as common in women than men
Young people
What is an AVRT
Accessory pathway - antegrade or retrograde depolarisation
Most common is WPW
Why does AVRT cause upsloping QRS
Accessory pathway allows depolarisation o ventricles before main electrical signal reaches AV node
Risk in WPW
AF, VF
Symptoms of AVRT/AVNRT
Rapid regular palpitations, abrupt onset and sudden termination
Dizziness
Dyspnoea
Central cehst pain and syncope
Worsened by exertion, coffee, tea or alcoohl
When is VT more likely than SVT
History of IHD
QRS >140ms
AV dissociation (no p wave +QRS relation)
Intermittent normal QRS
RS >100ms
Deep S wave V6
Concordant QRS direction V1-V6 eg all negative or positive
Acute management of SVTs haemodynamically unstable
Emergency cardioversion
Long term management of SVTs
Radiofrequency ablation of accessory pathway via cardiac catheter
Flecanide, verapamil, sotalol and amiodarone
Acute management of SVTs haemodynamically stable
Vagal stimulatino - valsalva manuvre - blow into plunger
Or right carotid sinus masage
Adenosine - AV node blocking IV6mg->12mg->18mg
IV verapamil or beta blocker eg metorpolol
Emergency treatment of arrhythmias
Oxygen, IV access
Test and correction of magnesium, potassium, calcium
Features of long QT syndrome
1 - exertional syncope
2 - syncope on stress, exercise or auditory sitmulus
3 - at rest or night
Sudden cardiac death
-> torasades de pointes
Management long QT syndrome
Beta blockers
Avoid precipitating drugs
ICD if high risk
Drugs -> long QT syndrome
Amiodarone, sotallol, 1a antiarrhythmics
TCAs, SSRIs
Chloroquine
mETHADONE
Terfenadine
Haloperdiol
Erythromycin
Ondanestron
Congenital causes Long qt syndrome
Javell lange nielson - deafness - abnormal K+
Romano ward syndrome
Other causes of long QT (not congenital or drugs)
Electroly - hypocalcemia, kaelmai, magnesia
Acute MI
hYPOTHERMIA
sah
myocarditis
Management of VT
Adverse signs - cardiovert
Amiodarone - central line
Lidocaine - caution in LV dysfunction
Procainamide
BPM in VT vs VF
VT - 100-250
VF>300
When long term manage SVT
Symptoms -> affect QOL
Symptomatic WPW
Infrequent but sports, driver etc
DC cardioverison antioag rules
3 weeks prior if >48 hrs AF
Urgent -> LMWH + oral anticcoag prior
Heparin post DC cardiovert + oral anticaog
CHADVASC vs HASBLED when anticoagulate
> 2 CHADVASC = anticoagulate needed
3 HASBLED = high bleeding risk
When do ratevs rhythm control AF
> 65, history IHD -> rate
<65, symptomatic, 1st presentation, lone AF or secondary to precipitant -> rhythm
Side effects atropine
Bradycardia and AV block
Facial flushing, headache, chest pain or tightness
Bronchospasm, sense impending doom
CIs atropine
Asthma
Second or third degree HB
Sick sinus syndrome unless pacemaker
Amiodarone side effects
Proarrhythmogenic in structurahl HD
Contains iodine - can cause hypo or hyperthyroidism
liver toxicity - monitor 6 monthly
ProlongsQT interval
Dzzled by lights
Phototoxic skin reactions
Slate grey skin
Peripheral neuropathy
PNeumonitis
CIs amiodarone
Sinus bradycardia
SAN block
Thyroid dysfunction
Iodine sensitivity
Flecanide side effects
Dizzy, visual disturb, SOB, palpitations, proarrhtyhmic, headahce, fatirgue and dnausea - common
Rare - bronchospasm, heart block, bone marrow supression, increased V rate in AF
Flecanide CI
Prev MI
CAD, LVSD, other structural HD
Interactions w beta blockers and CCBs
Digoxin side effects
N+V, diarrhoea, blurre or yellow vision
V arrhtyhmias. narrow therapeutic index - common
Hypokalemia and renal impairment
Toxicity -> hyperkalemai
CI digoxin
Sev renal impariemtn
accessory pathway arrhythmias
With amiodarone
Caution in LV obstruction
Dilatazem, verapamil, spirinolactone decrease renal excretion - plasma levels check
CI for ACEis/ARB
Bilateral renal artery stenosis
Pregnanyc
Angioedema
Sev renal failure
Sev or symptomatic mitral or aortic stenosis
HOCM
Pregnancy not CI in ARB
Caution in lvier impariment and elderly
Side effects ACEi
Dry cough
Hyperkalaemia
Sudden renal function dererioration if renal artery stenosis
NSAids - loss of testa, rashes, hypersensitvityy
CCB side effects
Flushing, dizzy, tachy, hypotension, ankle swell, headahce - vasodilating effects
Constipation w verapamil
Worsening HF - verapamil and dilatazem
CCB CIs
AORTIC STENOSIS
beta blockers, LV failure, sick sinus syndrome, HF
WPW, post MI - verapamil
Nitrates CI
Arotic/mitral stenosis
HOCM
Cardiac tamponade
Constrictive pericartitis
Classes of antiarrhythmics
Class I: membrane stabilising drugs (e.g. lidocaine, flecainide)
Class II: beta-blockers
Class III: amiodarone; sotalol (also Class II)
Class IV: calcium-channel blockers (includes verapamil but not dihydropyridines)
Torsades de points drug treatment
IV magnesium sulphate
