cardio Flashcards
What are the two main focusses when treating arrhythmia’s?
Rate control and rhthym control
what does “rate control” control?
Ventricular rate
What does “rhythm control” control?
the sinus rhythm
how do you control rhythm in arrthymias?
Cardioversion
Two types: Electrical and pharmacological
If AF symptoms are present for more than 48 hours what type of cardio version do you give?
-Electrical cardioversion is preferred but should not be attempted until the patient is fully coagulated for three weeks as a clot could come loose and cause a stroke.
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If you want to treat a new onset arrhytmia (AF), and it has life threatening haemodynamic instability (emergency) , how do you treat it?
- emergency electrical cardioversion
- give parenteral anticoagulant and rule out left atrial thrombus immediately before procedure
In acute new-onset presentation of AF how do you treat it if symptoms have presented for less than 48 hours?
- Rate or rhythm control - electrical cardioversion or amiodarone/flecanidie
In acute new-onset presentation of AF how do you treat it if symptoms have presented for more than 48 hours?
- RATE CONTROL
- verapamil, beta blocker
What is the first-line maintenance drug treatment for AF?
first line: RATE CONTROL
- Beta blocker (not sotalol)
- Rate limiting CCB - verapamil or diltaziam
- Digoxin ( only be considered in patients with non-paroxysmal AF who are predominantly sedentary)
if monotherapy doesn’t work, move on to dual therapy then rhythm control
what is the second-line maintanance drug treatment of AF?
- RHYTHM CONTROL
- Beta blocker or oral anti-arrythmic drug amiodarone, flecanide
How do you treat paroxysmal AF?
- Ventricular or rhythm control - standard Beta blocker or oral-antiarrhythmic drug. Dronedarone
All patients with AF should be assessed for their risk of stroke and need for thromboprophylaxis (anticoagulant). what scores are used to assess this?
CHADVASC Score - Assesses risk of stroke
ORBIT bleeding risk tool (HASBLED) - Risk of bleeding score
what risk factors does the CHADVASC score take into account and what score must someone have to be on anticoagulant?
- Age
- Gender - Female (scores 1)
- History of VTE , congestive heart failure
- hypertension
- diabetes
- Anticoagulation should be offered for stroke prevention to all patients with a CHA2DS2-VASc score of 2 or above.
How often should CHADVASC scores be reviewed in a patient?
Annually
Why is an anticoagulant given to patients who have AF?
Stroke prevention
If a patient with AF has a CHADVASC score of 2 and is going to be given an anticoagulant, what anticoagulant is given and what does the choice of anticoagulant depend on?
NEW ONSET AF:
- parenteral anticoagulant is given like heparin
Diagnosed AF:
- Warfarin or NOAC
In treatment of AF, when should flecainide and propafenone be avoided?
In patients with known inschaemic or structural heart disease.
How do you treat patients with symptomatic paroxysmal AF with infrequent episodes?
“PILL IN POCKET” - if patient has infrequent episodes they can treat themselves when they get symptoms with flecainide or propafenone.
How do you treat pulseless ventricular tachycardia ?
immediate defibrillation and CPR.
How do you treat unstable ventricular tachycardia?
direct current cardioversion
if this doesn’t work IV amiodarone and repeat direct current
How do you treat stable sustained ventricular tachycardia?
IV anti-arrhymic drug ( amiodarone, flecainide, propafenone)
What is given as maintenance therapy after a ventricular tachycardia?
- implantable cardioverter defibrillator
- B-blocker or combined with amiodarone
What is torsade de pointes and what can cause it?
Form of ventricular tachycardia associated with a long QT interval
- caused by drugs, hypokalaemia, severe bradycardia etc
How do you treat torsade de pointes?
IV magnesium sulfate
B-blocker can be considered (not sotalol)
What is paroxysmal supra ventricular tachycardia and how can you non-pharmalogically treat it?
- tachycardia that spontaneously terminates
- another way to terminate it is through the valsalva manouvre, immersing the face in cold water or carotid sinus massage.
how do you treat paroxysmal supraventricular tachycardia and what are the contraindications of the drug? what is the second line treatment
- IV adenosine
- contraindicated in asthma and COPD,
SECOND LINE:
verapamil
contraindicated in patients recently treated with b-blockers
what are the directions for administration for adenosine?
Rapid IV - give over 2 seconds into central or large peripheral vein followed by rapid sodium chloride 0.9% flush.
how do you treat paroxysmal supraventricular tachycardia in haemodynaically unstable patients?
Direct current cardioversion
how do you treat patients with recurrent episodes of paroxysmal supraventricular tachycardia?
- catheter ablation
- diltiazem, verapamil
- beta blockers including sotalol
- anti-arrhytmics like flecainide or propafenone
What type of anti-arrhythmic drug is amiodaron, the indication for amiodarone ?
Class III anti-arrhythmic
treatment of arrhythmias - supraventricular and ventricular
what is the initial loading dose of amiodarone?
- 200mg TDS for 7 days
- 200mg BD for 7 days
- 200mg OD as maintanance
What kind of side effects can amioadone cause ? (special side effects)
EYES
- Corneal microdeposits
- counsel patients on driving at night-time as there could be a glare due to blurred vision.
- optic neuropathy can occur so patients should stop taking if Vision is impaired as can cause blindness.
SKIN
- phototoxicity
- patients should be advised to shield skin from light during treatment and for several months after discontinuing amiodarone. use wide-spectrum sun cream.
NERVES
- peripheral neuropathy
LUNGS
- If new or progressive shortness of breath or cough develops in patients , pulmonary toxicity should be suspected. Pulmonary toxicity is usually reversible following early withdrawal of amiodarone.
LIVER
- hepatotoxicity
- stop treatment if severe liver function abnormalities or clinical signs of liver disease develops
THYROID DYSFUNCTION
- it contains iodine which can cause hypo and hyperthyroidism.
- hypothyroidism can be treated with levothyroxine without stopped amiodarone.
What is the MHRA alert for amiodarone?
- use of amiodarone with sofosbuvir and daclatasvir, simeprevir and sofosbuvir, or sofosbuvir and ledipasvir can cause bradycardia and heart block
- amiodarone can cause eyes, skin, liver, thyroid and lung problems.
What are the monitoring requirements for amiodarone?
- Liver function tests before treatment and every 6 months
- thyroid function tests before treatment and every 6 months : T3,T4 and TSH
- serum potassium levels
- Chest X Ray
- Patients taking sofosbuvir and daclatasvir, simeprevir and sofosbuvir, or sofosbuvir and ledipasvir should be closely monitored during first weeks of treatment. pt’s at high risk of bradycardia should be monitored for 48 hours in clinical setting.
- blood pressure and ECG - in IV use
Does amioadarone have a long half-life?
Yes 50 days so it can interact with drugs several months after stopping
What drugs does amiodarone interact with?
- Grapefruit Juice - Increased plasma amiodarone concentrations
- Warfarin, phenytoin, digoxin - it is an enzyme inhibitor
- Statins - risk of myopathy
- BBlockers, rate limiting CCBs - can cause bradycardia, AV block and myocardial depression
- Quinolones, macrolides, TCAs, SSRIs, lithium, quinine, anti-malarial, antipsychotics - QT prolongation - increased risk of ventricular arrhythmias
What drug class is digoxin and how does it work?
cardiac glycoside
What drug class is digoxn and how does it work?
cardiac glycoside and it increases the force of myocardial contraction and reduces conductivity within the AV node.
Digoxin is a narrow therapeutic drug. what is its therapeutic level?
1-2micrograms/L
After giving digoxin loading dose, when should its therapeutic levels be monitored?
6 hours after dose.
Regalar monitoring is not require during maintanance treatment unless toxicity suspected or in renal impairment (renally cleared)
What doses of digoxin do you give for maintanance of arrthymias and heart failure?
arrhytmias: 125-250 microgram
heart failure: 62.5-125 microgram
What are the signs of digoxin toxicity?
- SLOW AND SICK
- bradycardia and heart block
- nausea and vomiting and diarrhoea and abdominal pain
- blurred or yellow vision
- confusion, delirium
- rash
what is the treatment of digoxin?
withdraw
correct elelctrolyte imbalance