Week 4 - Arrhythmia 2 Flashcards
What are ventricular ectopics?
random premature ventricular contractions caused by random electrical discharges. normal, but more common in those with underlying heart disease.
How do you deal with a patient with ventricular ectopics?
check ECG which may have single broad QRS complex. check bloods for anaemia, thyroid hormones and electrolytes, reassure patient
What is torsades de pointes?
long QT syndrome. prolonged QT shows prolonged repolarisation, so ventricle may contract before repolarisation is over. this may reset sinus rhythm, or kick off ventricular tachycardia - cardiac arrest.
What are cause and treatment of torsades de pointes?
congenital, drugs or electrolyte disturbance. common.
treat cause or use defibrillator if VT occurs
What is sick sinus syndrome and how can it be prevented?
sinus node fails to generate impulse, causing bradycardia or syncope. pacemakers prevent the bradycardia.
What is 1st degree heart block?
PR interval greater than 0.2s as there is delayed conduction through AV node
What is 2nd degree heart block?
2 types
1 - PR interval slowly increases until QRS is skipped. then resets in cycle.
2 - PR interval stays the same, but every so often p wave fails to conduct
What is 3rd degree heart block?
complete heart block. p wave is regular but no relation to QRS complex or ventricular activity. ventricles contract spontaneously. need pacemaker
What is mobitz type I heart block?
atrial impulse becomes weaker gradually until it doesn’t pass through to AV node. after failing to stimulate AV node, it resets back to strength
What is mobitz type II heart block?
failure of AV conduction for each atrial contraction. may see 3 p waves for each QRS wave - 3:1 heart block.
What are indications for inserting a pacemaker?
- symptomatic or profound 2nd and 3rd degree heart block, when its unlikely to disappear.
- asymptomatic patients who may become symptomatic in the future
- before/after AV node ablation
What is the result of AV/heart block?
bradycardia, possible asystole
What is ICD therapy?
implantable cardioverter difibrillator. acts as pacemaker and cardioverter. wont feel pacing but can feel when cardioverting, when not blacked out.
What is radiofrequency ablation?
catheter up femoral vein to heart, under local or general anaesthetic. heat and destroy tissue which is causing abnormal electrical activity. should stop arrhythmia.
What are indications for ICD therapy?
secondary prevention. ventricular tachycardia VT.
