Editing Pacemaker (section)

{{Short description|Medical device for artificially stimulating heart contractions}}
{{otheruses}}
{{about|the medical device that simulates the function|the natural pacemaker in the heart|Cardiac pacemaker}}
{{Infobox medical intervention
| name         = Pacemaker
| image        = St Jude Medical pacemaker with ruler.jpg|
| caption      = [[St. Jude Medical#Products|St. Jude single-lead pacemaker]] with ruler in cm (released in 2005<ref>{{Cite web |title=Devices@FDA |url=https://www.accessdata.fda.gov/scrIpts/cdrh/devicesatfda/index.cfm?db=pma&id=334237 |access-date=2022-04-27 |website=www.accessdata.fda.gov}}</ref><ref>{{Cite report |publisher=St. Jude Medical |date=October 2008 |title=Product Performance Report – Cardiac Rhythm Management |url=https://www.cardiovascular.abbott/content/dam/bss/divisionalsites/cv/pdf/reports/1.3.7.3/Oct_2008_PPR_060711.pdf |access-date=2022-04-27 |archive-date=2022-08-19 |archive-url=https://web.archive.org/web/20220819090738/https://www.cardiovascular.abbott/content/dam/bss/divisionalsites/cv/pdf/reports/1.3.7.3/Oct_2008_PPR_060711.pdf |url-status=dead }}</ref>)
| alt          = 
| pronounce    = 
| synonyms     = 
| ICD10        = 
| ICD9         = 
| ICD9unlinked = 
| MeshID       = 
| LOINC        = 
| other_codes  = 
| MedlinePlus  = 
| eMedicine    = 
|specialty=[[Cardiology]], [[electrophysiology]]}}

A '''pacemaker''', also known as an '''artificial cardiac pacemaker''', is an [[Implant (medicine)|implanted]]  [[medical device]] that generates [[Pulse (signal processing)|electrical pulses]] delivered by [[electrode]]s to one or more of the [[Heart chamber|chambers of the heart]]. Each pulse causes the targeted chamber(s) to [[muscle contraction|contract]] and pump blood,<ref>{{Cite web |title=UpToDate |url=https://www.uptodate.com/contents/pacemakers-beyond-the-basics/print#:~:text=The%20conduction%20system%20stimulates%20precise,sinus%20node%20(figure%201). |access-date=2022-08-02 |website=www.uptodate.com}}</ref> thus regulating the function of the [[electrical conduction system of the heart]].

The primary purpose of a pacemaker is to maintain an even [[heart rate]], either because the heart's natural [[cardiac pacemaker]] provides an inadequate or irregular heartbeat, or because there is a [[heart block|block]] in the heart's electrical conduction system. Modern pacemakers are externally programmable and allow a cardiologist to select the optimal pacing modes for individual patients. Most pacemakers are on demand, in which the stimulation of the heart is based on the dynamic demand of the [[circulatory system]]. Others send out a fixed rate of impulses.<ref name="bhf">{{cite web |title=Pacemakers |url=https://www.bhf.org.uk/informationsupport/treatments/pacemakers |access-date=28 July 2022}}</ref>

A specific type of pacemaker, called an [[implantable cardioverter-defibrillator]], combines pacemaker and [[defibrillator]] functions in a single [[Implant (medicine)|implantable device]].<ref>{{Cite web |title=Overview of Pacemakers and Implantable Cardioverter Defibrillators (ICDs) – Health Encyclopedia – University of Rochester Medical Center |url=https://www.urmc.rochester.edu/encyclopedia/content.aspx?contenttypeid=85&contentid=p00234 |access-date=2022-08-02 |website=www.urmc.rochester.edu}}</ref> Others, called [[Cardiac resynchronization therapy|biventricular pacemakers]], have multiple electrodes stimulating different positions within the ventricles (the lower heart chambers) to improve their synchronization.<ref>{{Cite web |title=Biventricular Pacemaker |url=https://my.clevelandclinic.org/health/treatments/16784-biventricular-pacemaker |access-date=2022-08-02 |website=Cleveland Clinic}}</ref>
{{toclimit|3}}