Arrhythmias Flashcards
Class I Anti-Arrhythmics
Na Blockers - disopyramide, lidocaine, flecainide
Class I Anti-Arrhythmics CI/warnings
CI- severe asthma/COPD
warning: structural/ ischeamic HD
Class II Anti-Arrhythmics
B blockers
Class III Anti-Arrhythmics
K Blockers - amiodarone, sotalol, dronedarone
Dronedarone ADRs
Hepatotox and HF
Class IV Anti-Arrhythmics
Rate lim. CCBs (Dil & Ver)
Other Anti-Arrhythmics
Digoxin (sedentary non-pAF, cong HF), adenosine
Electro or Pharmo Cardioversion
Pharmo must be w/i 48h of symptoms or inc risk of stroke. Electro preferred if >48hrs post symptoms (wait 3 wks post anticoag, wait 4 wks post cardioversion before stopping anticoag.) If heamodynamically unstable, electocardioversion (give parenteral antiocoag & rule out atrial thrombus before procedure)
AF Maintenance
1st line rate (B blocker, rate lim CCB, digoxin)
Monotherapy-> dual therapy -> rhythm control
Rhythm control- B blockers, antiarythmics
Pill in pocket (anti-arryhthmics eg flecanide) for infrequent episodes of pAF.
New onset AF
W/ life threatening heamodynamic instability- electrocarioversion
W/o life threatening heamodynamic instability:
<48hrs - rate/rhythm control (electrical or amiodarone/flec)
>48hrs - rate control only (verapamil or B blocker)
AF stroke prevention
anticoag if stroke risk (CHA2DS2VASc) >bleed risk (HAS-BLED)
give anticoag if score 2 or more on chadsvasc, no anticoag req if man=0 or woman=1
CHA2DS2VASc
C- chronic HF/LVD H- hypertension A2- Age 75+ D- diabetes S- stroke/tia/VTE history V- vascular disease A- age 65-74 Sc - Sex category
Ventricular tachycardias immediate treatment
Pulseless/fib - immediate defib and CPR
unstable sustained: direct current cardioversion (repeat w/ amiodarone if unsuccessful)
Stable sustained : IV amiodarone
Unsustained : B blocker
Ventricular tachycardias maintenance
High risk of cardiac arrest
Most patients require defib implant
some also require drugs - sotalol, B-Blocker (w/ or w/o amiodarone)
Torsades de Pointes (QT prolongation)
Treatment: Magnesium sulphate
Causes: Sotalol and other QT prolongers, hypokal, bradycardia.
Amiodarone ADRs: skin
slate grey skin, phytotoxicity (counsel to cover skin and use sun cream for months after finishing amiodarone)
Amiodarone ADRs: eyes
Corneal deposits (counsel- night time glare whilst driving), optic neuropathy leading to blindness (couple to stop if any vision disturbances/loss)
Amiodarone ADRs: nerves
Peripheral neuropathy (counsel- may feel tingling etc in extremities)
Amiodarone ADRs: lungs
pneumonitis, pulmonary fibrosis (counsel- look for SOB, dry cough)
Amiodarone ADRs: liver
hepatotoxicity (counsel- signs of hepatotox, inc. itching, jaundice, signs of bleeding, etc)
Amiodarone ADRs: Thyroid
Hyper (weight loss, heat intolerance, tachycardia), start carbimazole, stop amiodarone
Hypo (weight gain, cold intolerance, bradycardia), starts levothyroxine if necessary, w/o w/d amiodarone
Amiodarone monitoring
annual eye test, chest X-ray before starting, LFTs 6/12, TFTs 6/12, BP, ECG, U&Es (K+).
amiodarone interactions
enzyme inhibitor, so reduced doses may be required for warfarin, phenytoin, digoxin required half m=normal dose
Inc risk of myopathy with statins
Bradycardia, AV block, myocardial depression with B blockers, and Rate lim CCBs
QT prolongation- other drugs include quinolones, macrolides, TCAs, (es)citalopram, quinine and analogues, antipsychotics, fluconazole
Digoxin MOA
Increases myocardial force of contraction (+ inotrope), reduces AVN conduction (- chronotrope)
