Pacemakers Flashcards
What are pacemakers?
They are devices that deliver controlled electrical impulses to specific areas of the heart to restore the normal activity and improve the heart function
What do pacemakers consist of?
Pulse generator
Pacing leads
Where is the pulse generator located?
It is implanted under the skin in the left anterior chest wall
Where are pacing leads located?
They are implanted into the relevant chambers of the heart
What are the five indications for a pacemaker?
Symptomatic Bradycardia
Mobitz Type II Heart Block
Third Degree Heart Block
Severe Heart Failure
Hypertrophic Obstructive Cardiomyopathy
What are the four pacemaker types?
Single Chamber Pacemaker
Dual Chamber Pacemaker
Biventricular Pacemaker
Implantable Cardioverter Defibrillator (ICDs)
What are single chamber pacemakers?
They are pacemakers that have leads in a single chamber, either in the right atrium or right ventricle
When do we insert a single chamber pacemaker into the right atrium? Why?
When the AV conduction in the patient is normal, however there are issues with the SA node
They allow depolarisation in the right atrium to be stimulated and this electrical activity then passes to the left atrium through the AV node to the ventricles in the normal way
When do we insert a single chamber pacemaker into the right ventricle? Why?
When the AV conduction in the patient is abnormal
They allow the ventricles to be stimulated directly
What are dual chamber pacemakers?
They are pacemakers that have leads in both the right atrium and right ventricle
What is the function of dual chamber pacemakers?
They synchronise the contractions of both atria and ventricles
What is another term for biventricular pacemakers?
Cardiac resynchronisation therapy (CRT)
What are biventricular pacemakers?
They have leads in the right atrium, right ventricle and left ventricle
When do we insert a biventricular pacemaker?
In severe heart failure
What are implantable cardioverter defibrillator (ICDs)?
They are pacemakers that continually monitor the heart and apply a defibrillator shock to cardiovert the patient back into sinus rhythm if they identify a shockable arrythmia
