Pacemakers Flashcards
what is the function of pacemakers
deliver controlled electrical impulses to specific areas of the heart to restore the normal electrical activity and improve heart function
what do pacemakers consist of (2)
- pulse generator (box)
- pacing leads
where in the body is the pacemaker generally implanted (2)
- box –> left anterior chest wall or axilla, under the skin
- wires implanted to relevant heart chambers
how long do the batteries of modern pacemakers normally last
5 years
what can be contraindications for pacemakers (2)
- MRI (thought many modern now MRI compatible)
- electrical interventions e.g. TENS machines and diathermy
why must a pacemaker be removed before cremation
potential to blowup crematorium
what are the indications for a pacemaker (5)
- symptomatic bradycardias
- Mobitz type 2 AV block
- third degree heart block
- severe heart failure
- hypertrophic obstructive cardiomyopathy
give the types of pacemaker (3) and the difference between them (3)
Single
- leads in a single chamber either RA or RV
Double
- leads in both RA and RV
Biventricular
- leads in RA, RV and LV
when will single chamber pacemaker leads be placed in the RA
if AV conduction in Px is normal and issue is with SA node
when will single chamber pacemaker leads be placed in the RV
if AV conduction in Px is abnormal so leads will stimulate ventricle directly
what Px would receive a biventricular pacemaker
Px w/ HF
what is another name for biventricular pacemakers
cardiac resynchronisation therapy (CRT) pacemakers
what is an ICD and what does it do (2)
- implantable Cardioverter defibrillator
- continually monitors heart and applies defibrillator shock to Cardioverter the Px back to sinus rhythm if they identify a shockable arrhythmia
in ECGs what does a line before each P wave indicate regarding pacemakers
lead present in RA
in ECGs what does a line before each QRS complex indicate regarding pacemakers
lead present in RV
