View source for Premature ventricular contraction

{{short description|Skipped human heartbeat with ventricular origin}}
{{about|the heart condition|PVC pipe|Polyvinyl chloride}}
{{Infobox medical condition (new)
| name = Premature ventricular contraction
| synonyms = Premature ventricular complex, ventricular premature contraction (complex or complexes) (VPC), ventricular premature beat (VPB), ventricular extrasystole (VES)
| image = Ectopic focus (no title).svg
| caption = Premature ventricular contraction usually originates from an area of [[ectopic focus]]. In this illustration ectopic area is near [[papillary muscles]] in the [[left ventricle]]. Most commonly in healthy hearts PVCs occur near [[right ventricular outflow tract]] (RVOT).
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| field = [[Cardiology]]
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| image2 = PVC10.JPG
| alt2 = 
| caption2 = A premature ventricular contraction on an [[EKG]], marked by the arrow
}}
<!-- Definition and symptoms -->
A '''premature ventricular contraction''' ('''PVC''') is a common event where the [[heart rate|heartbeat]] is initiated by [[Purkinje fibers]] in the [[Ventricle (heart)|ventricle]]s rather than by the [[sinoatrial node]]. PVCs may cause no symptoms or may be perceived as a "skipped beat" or felt as [[palpitations]] in the chest. PVCs do not usually pose any danger.<ref name=Gers2019>{{cite journal |last1=Gerstenfeld |first1=EP |last2=De Marco |first2=T |title=Premature Ventricular Contractions. |journal=Circulation |date=20 August 2019 |volume=140 |issue=8 |pages=624–26 |doi=10.1161/CIRCULATIONAHA.119.040015 |pmid=31424993|doi-access=free }}</ref>

<!-- Cause and diagnosis -->
The electrical events of the heart detected by the [[electrocardiogram]] (ECG) allow a PVC to be easily distinguished from a normal heart beat. However, very frequent PVCs can be symptomatic of an underlying heart condition (such as [[arrhythmogenic right ventricular cardiomyopathy]]). Furthermore, very frequent (over 20% of all heartbeats) PVCs are considered a risk factor for [[arrhythmia-induced cardiomyopathy]], in which the heart muscle becomes less effective and symptoms of [[heart failure]] may develop.<ref name=Akdemir2016>{{cite journal|last1=Akdemir|first1=B.|last2=Yarmohammadi|first2=H.|last3=Alraies|first3=M. C.|last4=Adkisson|first4=W. O.|title=Premature ventricular contractions: Reassure or refer?|journal=Cleveland Clinic Journal of Medicine|date=1 July 2016|volume=83|issue=7|pages=524–30|doi=10.3949/ccjm.83a.15090|pmid=27399865|doi-access=free}}</ref> [[Echocardiography|Ultrasound of the heart]] is therefore recommended in people with frequent PVCs.

<!-- Treatment and epidemiology -->
If PVCs are frequent or troublesome, medication ([[beta blocker]]s or certain [[calcium channel blocker]]s) may be used. Very frequent PVCs in people with [[dilated cardiomyopathy]] may be treated with [[Radiofrequency ablation#Cardiology|radiofrequency ablation]].<ref name=Akdemir2016/><ref name=Gers2019/>

==Signs and symptoms==
{{Listen|filename=|title=Sounds of an irregular heartbeat.|description=Heart sounds of a 16 year old girl with premature ventricular contractions and other types of ectopic beats.|pos=[[wav]]}}
{{listen|filename=|title=Sound of a teen's heart during tachycardia.|description=Auscultation of a 14 year old female's racing heart during an episode of tachyarrhythmia. PVCs and other ectopic beats are audible in the recording.|format=[[wav]]}}
Although there are many possible symptoms associated with PVCs, PVCs may also have no symptoms at all. PVCs may be perceived as a skipped heart beat, a strong beat, [[palpitations]], or [[lightheadedness]]. They may also cause chest pain, a faint feeling, fatigue, or [[hyperventilation]] after exercise.<ref name=Akdemir2016/> Symptoms may be more pronounced at times of stress. Women may be more aware of PVCs at the time of the [[menstrual period]].<ref name=Akdemir2016/>

Premature ventricular contractions may be associated with underlying heart disease, and certain characteristics are therefore elicited routinely: the presence of signs of heart disease or a known history of heart disease (e.g. previous [[myocardial infarction]]), as well as heart disease or [[sudden cardiac death]] in close relatives. PVCs and palpitation associated with [[Syncope (medicine)|syncope]] (transient loss of consciousness) or provoked by exertion are also concerning.<ref name=Akdemir2016/> Physical examination is focused on identifying evidence of underlying heart disease.<ref name=Akdemir2016/>

==Causes==
[[File:VPC 1.png|thumb|upright=1.6|Premature ventricular contraction in an ECG (arrows) of a dog, caused by dilated cardiomyopathy.]]
Premature ventricular contractions occur in healthy persons of any age, but are more prevalent in the elderly and in men.<ref name="keany2">{{cite journal |last1=Keany |first1=James E. |last2=Desai |first2=Aseem D. |date=13 January 2017 |editor1-last=Schraga |editor1-first=Erik D. |title=Premature Ventricular Contraction |website=[[eMedicine]] |url=http://emedicine.medscape.com/article/761148-overview }}</ref> In a very significant proportion of people they occur spontaneously with no known cause.{{cn|date=August 2022}} <!-- PLEASE RESPECT ALPHABETICAL ORDER WHERE POSSIBLE -->

Some possible underlying causes of PVCs include:

=== Non-cardiac causes ===
* [[Adrenaline]] excess
* [[Anemia]]<ref name=":0">{{Citation |last1=Farzam |first1=Khashayar |title=Premature Ventricular Contraction |date=2022 |url=https://www.ncbi.nlm.nih.gov/books/NBK532991/ |work=StatPearls |place=Treasure Island (FL) |publisher=StatPearls Publishing |pmid=30422584 |access-date=2022-04-27 |last2=Richards |first2=John R.}}</ref>
* [[Catecholamine]] excess
* Certain medicines such as [[tricyclic antidepressant]]s,<ref name="keany2" /> [[digoxin]], [[Sympathomimetic drug|sympathomimetics]], [[aminophylline]]<ref name=":1">{{Cite journal |title=What are noncardiac causes of premature ventricular contractions (PVCs)? |url=https://www.medscape.com/answers/761148-110884/what-are-noncardiac-causes-of-premature-ventricular-contractions-pvcs |access-date=2022-05-28 |website=www.medscape.com|date=17 October 2021 }}</ref>
* Chemical (electrolyte) abnormalities in the blood<ref>{{MedlinePlusEncyclopedia|001100|Ectopic heartbeat}}</ref> (for example [[hypokalemia]] (low blood potassium), which can occur in those taking [[diuretics]] ("water pills")<ref name="Kulick3">{{Cite web |last=Kulick |first=David Lee |date=23 March 2016 |editor-last=Shiel |editor-first=William C. Jr. |url=http://www.medicinenet.com/premature_ventricular_contractions/page3.htm|title=Premature Ventricular Contractions (PVCs, PVC): What causes premature ventricular contractions? |access-date=2017-02-21|language=en|website=MedicineNet}}</ref> and [[hypomagnesaemia]] (magnesium deficiency)).
* Contact with the [[Carina of trachea|carina (trachea/bronchi)]] when performing medical suctioning stimulates [[vagus nerve]]
* [[Drugs]]/[[Substance abuse|substances]] such as:<ref name="keany2" />
** [[Amphetamines]]<ref name=":1" />
** [[Alcohol (drug)|Alcohol]]<ref name="emilsson2">{{Citation|title=Suspected association of ventricular arrhythmia with air pollution in a motorbike rider: a case report|date=3 June 2008|last=Emilsson |first=Kent |journal=Journal of Medical Case Reports|volume=2|page=192|doi=10.1186/1752-1947-2-192|pmc=2427047|pmid=18522736 |doi-access=free }} {{open access}}</ref>
** [[Caffeine]]<ref name="urlPremature ventricular contractions (PVCs) Causes - Diseases and Conditions - Mayo Clinic2">{{cite web |author=Mayo Clinic Staff |date=26 April 2014 |url=http://www.mayoclinic.org/diseases-conditions/premature-ventricular-contractions/basics/causes/con-20030205|title=Premature ventricular contractions (PVCs) Causes|website=Mayo Clinic|publisher=Mayo Foundation for Medical Education and Research }}</ref>
** [[Cocaine]]
** [[Nicotine]]
** [[Theobromine]]<ref>{{cite web|url=http://www.bodyrestorationanownersmanual.com/Cookbook/Contents/Methylxanthine.html|title=Methylxanthine Toxcity Syndrome|last1=Lebowitz|first1=Michael|website=Body Restoration: An Owner's Manual |access-date=25 January 2016}}</ref>{{Unreliable medical source|date=April 2017}}
* [[Hypercapnia]] ([[Carbon dioxide|CO<sub>2</sub>]] poisoning)<ref name="keany2" />
* [[Hypertension]] (high blood pressure)<ref name=":3">{{Cite news|url=http://www.mayoclinic.org/diseases-conditions/premature-ventricular-contractions/basics/risk-factors/con-20030205|title=Premature ventricular contractions (PVCs) Risk factors |work=Mayo Clinic|access-date=2017-03-01|language=en}}</ref>
* [[Hyperthyroidism]]<ref name=":0" />
* [[Hypercalcaemia|High blood calcium]]<ref name="keany2" />
* [[Hypoxia (medical)|Hypoxia]]<ref name="keany2" /> and/or [[hypercapnia]]<ref name=":1" />
* [[Sleep deprivation|Lack of sleep]]/[[Fatigue (medical)|exhaustion]]<ref name="guyton2">{{cite book |last1=Guyton |first1=Arthur C. |url=https://archive.org/details/textbookmedicalp00acgu |title=Textbook of medical physiology |last2=Hall |first2=John E. |publisher=Elsevier Saunders |year=2006 |isbn=0-7216-0240-1 |edition=11th |location=Philadelphia |page=[https://archive.org/details/textbookmedicalp00acgu/page/n185 151] |url-access=limited}}</ref>
* [[Sarcoidosis]]<ref name="birnie2">{{Citation |last1=Birnie |first1=David H. |title=HRS Expert Consensus Statement on the Diagnosis and Management of Arrhythmias Associated With Cardiac Sarcoidosis |date=July 2014 |journal=Heart Rhythm |volume=11 |issue=7 |pages=1304–23 |doi=10.1016/j.hrthm.2014.03.043 |pmid=24819193 |last2=Sauer |first2=William H. |last3=Bogun |first3=Frank |last4=Cooper |first4=Joshua M. |last5=Culver |first5=Daniel A. |last6=Duvernoy |first6=Claire S. |last7=Judson |first7=Marc A. |last8=Kron |first8=Jordana |last9=Mehta |first9=Davendra |first13=Pekka |last14=Soejima |first14=Kyoko |last13=Raatikainen |first12=Tohru |first11=Amit R. |last11=Patel |first10=Jens Cosedis |last10=Nielsen |last12=Ohe}}</ref>
* [[Smoking]]
* [[Stress (biology)|Stress]]<ref name="guyton2" />
* [[Anxiety]]<ref name=":0" />

=== Cardiac causes ===
* Any structural heart disease which alters [[Electrical conduction system of the heart|electrical conduction pathways]] due to tissue alterations
* [[Cardiomyopathy]], [[Hypertrophic cardiomyopathy|hypertrophic]] or [[Dilated cardiomyopathy|dilated]]<ref name="keany2" />
* [[Myocardial infarction]]<ref name="ganz">http://www.uptodate.com/patients/content/topic.do?topicKey=hrt_dis/11733,{{Dead link|date=April 2017}} Up-to-date</ref>
* [[Myocarditis]]<ref name="keany2" />
* [[Blunt cardiac injury|Myocardial contusion]]<ref name="keany2" />
* [[Mitral valve prolapse]]<ref name="keany2" />

==Pathophysiology==
{{more citations needed section|date=May 2018}}
[[File:Ectopic focus.svg|thumb|An illustration of [[Ectopic pacemaker|ectopic foci]] near [[papillary muscle]]s in the [[Left Ventricle|left ventricle]]. Ectopic foci can be located anywhere in the ventricles in the case of PVCs.]]
Normally, impulses pass through both ventricles almost at the same time and the depolarization waves of the two ventricles partially cancel each other out in the ECG. However, when a PVC occurs the impulse nearly always travels through only one bundle fiber, so there is no neutralization effect; this results in the high voltage QRS wave in the electrocardiograph.

There are three main physiological explanations for premature ventricular contractions: enhanced ectopic nodal automaticity, re-entry signaling, and toxic/reperfusion triggered.

Ectopic enhanced nodal automaticity suggests foci of sub-pulmonic valvular pacemaker cells that have a subthreshold potential for firing. The basic rhythm of the heart raises these cells to threshold, which precipitates an ectopic beat. This process is the underlying mechanism for arrhythmias due to excess catecholamines and some electrolyte deficiencies, particularly [[hypokalemia|low blood potassium]], known as hypokalemia.

Reentry occurs when an area of 1-way block in the [[Purkinje fiber]]s and a second area of slow conduction are present. This condition is frequently seen in patients with underlying heart disease that creates areas of differential conduction and recovery due to myocardial scarring or ischemia. During ventricular activation, one bundle tract's area of slow conduction activates the other tract's bundle fibers post block after the rest of the ventricle has recovered. This resulting in an extra beat. Reentry can produce single ectopic beats, or it can trigger paroxysmal tachycardia.

Triggered beats are considered to be due to after-depolarizations triggered by the preceding action potential. These are often seen in patients with ventricular arrhythmias due to digoxin toxicity and reperfusion therapy after myocardial infarction (MI).

This ectopy of the ventricles when associated with a structurally normal heart most commonly occurs from the [[right ventricular outflow tract]] (RVOT) under the pulmonic valve. The mechanism behind this is thought to be enhanced automaticity versus triggered activity.<ref name="keany2" />

===Molecular basis===
There are a number of different molecular explanations for PVCs.
* calcium excess:  One explanation is most basically due to an increased amount of [[cyclic AMP]](cAMP) in the muscle cells of the heart's ventricles leading to increased flow of calcium ions into the cell. This may happen for the following reasons:

:*Activation of the sympathetic nervous system, due to anxiety and/or physiological stress, for example [[hypovolemia]] caused by [[dehydration]] or [[hemorrhage|bleeding]]. This activation can cause a release of [[catecholamines]] such as [[epinephrine]] (adrenaline) which can bind to [[beta-1 adrenergic receptor]] (β<sub>1</sub> receptors) on cardiac myocytes, activating a type of guanosine nucleotide-binding protein called [[Gs alpha subunit|Gs protein]].<ref name="nelson">{{harvnb|Nelson|Cox|2008|p=[{{google books|5Ek9J4p3NfkC|page=424|plainurl=yes}} 424]}}</ref> This type of protein stimulates the production of cAMP,<ref>{{harvnb|Levy|Pappano|2007|p=62}}</ref> ultimately increasing the flow of calcium ions from the extracellular space and from the sarcoplasmic reticulum into the cytosol.<ref>{{harvnb|Levy|Pappano|2007|p=24}}</ref><br /> This has the effect of (1) increasing the strength of contraction (inotropy) and (2) depolarizing the myocyte more rapidly (chronotropy). The ventricular myocytes are therefore more irritable than usual, and may depolarize spontaneously before the SA node depolarizes. Other sympathomimetic molecules such as [[amphetamines]] and [[cocaine]] will also cause this effect.
:*Phosphodiesterase inhibitors such as [[caffeine]] directly affect the G-coupled signal transduction cascade<ref>{{harvnb|Nelson|Cox|2008|p=430}}</ref> by inhibiting the enzyme that catalyzes the breakdown of cAMP,<ref name="nelson"/> again leading to the increased concentration of calcium ions in the cytosol.
* potassium deficiency: [[Potassium]] ion concentrations are a major determinant in the magnitude of the electrochemical potential of cells, and [[hypokalemia]] makes it more likely that cells will depolarize spontaneously. [[Hypercalcemia]] has a similar effect, although clinically it is of less concern.<!-- There remains a simple question for the several dozen watchers of this page (those who have the relevant bit of technical knowledge):  Is the article's immediately-foregoing hypercalcemia sentence essentially about the 'Calcium Excess' topic that is 3 paragraphs above?  If you know that answer, then please state it here.  If the answer is Yes, then such Calcium Excess topic should be demoted to here, below this Potassium Deficiency paragraph, and i myself would do such text-move for you.  Thank you very much. -->
* magnesium deficiency: [[Magnesium]] ions affect the flow of [[calcium]] ions, and they affect the function of the [[Na+/K+ ATPase]], and are necessary for maintaining potassium levels. [[Hypomagnesemia|Low blood magnesium]] therefore also makes spontaneous depolarization more likely.
* myocardium damage:  Existing damage to the myocardium can also provoke PVCs. The [[myocardial scarring]] that occurs in [[myocardial infarction]] and also in the surgical repair of [[congenital heart disease]] can disrupt the conduction system of the heart and may also irritate surrounding viable ventricular myocytes, make them more likely to depolarize spontaneously. Inflammation of the myocardium (as occurs in [[myocarditis]]) and systemic inflammation cause surges of [[cytokines]], which can affect the electrical properties of myocytes and may be ultimately responsible for causing irritability of myocytes.

== Diagnosis ==
[[File:NSR and Ectopic beats (PVC and PAC).svg|thumb|Normal sinus rhythm and ectopic beats - premature ventricular contractions (PVC) and premature atrial contractions (PAC) shown on an [[EKG]]]]
PVCs may be found incidentally on cardiac tests such as a 12-lead [[electrocardiogram]] (ECG/EKG) performed for another reason. In those with symptoms suggestive of premature ventricular complexes, the ECG/EKG is the first investigation that may identify PVCs as well as other cardiac rhythm issues that may cause similar symptoms. If symptoms are infrequent, other forms of continuous heart beat recording may be used, such as a 24 or 48-hour [[Holter monitor]]  or even 14- to 30-day recorders if the symptoms are very occasional.<ref name=Akdemir2016/> Consumer-grade wearable devices such as the Apple Watch, KardiaMobile, and Fitbit also offer intermittent ECG recording capabilities, allowing users to capture symptomatic episodes outside of traditional clinical settings. <ref>{{Cite web |title=What Premature Ventricular Contraction (PVC) Looks Like on Your Watch ECG {{!}} Qaly |url=https://www.qaly.co/post/premature-ventricular-contractions-pvcs |access-date=2025-04-22 |website=www.qaly.co |language=en}}</ref> 

The advantage of these monitors is that they allow a quantification of the amount of abnormal beats ("burden") and ensure that there are no [[heart arrhythmia]]s present that might require attention, such as [[ventricular tachycardia]].<ref name="Akdemir2016" /> If symptoms are associated with exercise, a supervised [[cardiac stress test]] may be required to reproduce the abnormality. Specifically, if this shows exercise-induced ventricular tachycardia this would require specific treatment.<ref name="Akdemir2016" /> If PVCs are suppressed by exercise, this is an encouraging finding.{{citation needed|date=May 2018}}

On electrocardiography (ECG or Holter) premature ventricular contractions have a specific appearance of the QRS complexes and T waves, which are different from normal readings. By definition, a PVC occurs earlier than the regular normally conducted beat. Subsequently, the time between the PVC and the next normal beat is longer as the result of a compensatory pause.<ref name="levy">{{harvnb|Levy|Pappano|2007|pp=49–50}}</ref> PVCs can be distinguished from [[premature atrial contraction]]s because the compensatory pause is longer following premature ventricular contractions, in addition to a difference in QRS appearance.<ref name="gomella">{{Citation |last1=Haist |first1=Steven A. |last2=Gomella |first2=Leonard G. |title=Clinician's pocket reference |publisher=McGraw-Hill |location=New York |series=Lange Clinical Science Series |year=2004 |page=[{{google books|KaegPx6LK2sC|keywords=unifocal PVC|plainurl=yes}} 390] |isbn=0-07-140255-1 |oclc=53929979 |edition=10th |chapter=19 Basic ECG Reading: Ventricular Arrhythmias }}</ref>

In some people, PVCs occur in a predictable pattern. Two PVCs in a row are called doublets and three PVCs in a rows are triplets. Depending whether there are one, two, or three normal ([[Sinus rhythm|sinus]]) beats between each PVC, the rhythm is called [[bigeminy]], trigeminy, or quadrigeminy. If 3 or more consecutive PVCs occur in a row it may be called [[ventricular tachycardia]].<ref name="gomella"/> The precise shape of the QRS can give an indication as to where precisely in the heart muscle the abnormal electrical activity arises. If someone has PVCs that all have the same appearance, they are considered "monofocal", if PVC’s have different appearance, they are considered “multifocal”.<ref name=Akdemir2016/>

==Treatment==
Isolated PVCs with benign characteristics and no underlying heart disease require no treatment, especially if there are limited symptoms.<ref name=Akdemir2016/>

The most effective treatment is the elimination of triggers (particularly stopping the use of substances such as [[caffeine]] and certain drugs, like tobacco).<ref name="Mayo">{{Cite news|url=http://www.mayoclinic.org/diseases-conditions/premature-ventricular-contractions/basics/treatment/con-20030205|title=Premature ventricular contractions (PVCs) Treatments and drugs |work=Mayo Clinic|access-date=2017-04-20|language=en}}</ref> If frequent, it’s possible to use:
* Medications
** [[Antiarrhythmic agent|Antiarrhythmics]]:<ref name="keany2"/> these agents alter the electrophysiologic mechanisms responsible for PVCs. In [[Cardiac Arrhythmia Suppression Trial|CAST study]] of survivors of [[myocardial infarction]] [[encainide]] and [[flecainide]], it was shown that, though those drugs could suppress PVC, they also increased the risk of death. However, while<ref name="Ng2006">{{cite journal | author = G André Ng | title = Treating patients with ventricular ectopic beats | journal = Heart | volume = 92 | issue = 11 | pages = 1707–12 | year = 2006 | pmid = 17041126 | doi = 10.1136/hrt.2005.067843 | pmc=1861260}}</ref> [[moricizine]] increased the death rate when used with [[diuretic]]s, it reduced the frequency of deaths when it was used alone.<ref>{{cite journal| last1=Anderson|first1=JL|last2=Platia|first2=EV| last3=Hallstrom|first3=A|last4=Henthorn|first4=RW|last5=Buckingham|first5=TA|last6 =Carlson|first6=MD|last7=Carson|first7=PE|title=Interaction of baseline characteristics with the hazard of encainide, flecainide, and moricizine therapy in patients with myocardial infarction. A possible explanation for increased mortality in the Cardiac Arrhythmia Suppression Trial (CAST)|journal=Circulation|date=December 1994|volume=90|issue=6|pages=2843–52|pmid=7994829|doi=10.1161/01.cir.90.6.2843|doi-access=free}}</ref>
** [[Beta blocker]]s: Reduce [[Myocardial contractility|cardiac contractility]] which makes PVCs less obvious to a person; possibly reduce catecholamine induced PVCs (in catecholamine-sensitive people) due to adrenaline not reaching [[Sinoatrial node|sinus node]] [citation needed]
** [[Calcium channel blocker]]s<ref name="ganz"/>
* Electrolytes replacement
** Magnesium supplements (e.g. magnesium citrate, orotate, Maalox, etc.)
** Potassium supplements (e.g. chloride potassium with citrate ion)
* [[Ablation of atrial fibrillation#Methods|Radiofrequency catheter ablation treatment]].<ref name="ganz"/> It is advised for people with ventricular dysfunction and/or [[tachyarrhythmia]] or very frequent PVC (>20% in 24 h) and normal ventricular function.<ref name="pmid15837260">{{cite journal | author = Belhassen B | title = Radiofrequency ablation of "benign" right ventricular outflow tract extrasystoles: a therapy that has found its disease? | journal = J. Am. Coll. Cardiol. | volume = 45 | issue = 8 | pages = 1266–68 | year = 2005 | pmid = 15837260 | doi = 10.1016/j.jacc.2005.01.028 | doi-access =  }}</ref> This procedure is a way to destroy the area of the heart tissue that is causing the irregular contractions characteristic of PVCs using radio frequency energy.<ref name="Kulick3" />
* [[Implantable cardioverter-defibrillator]]<ref name=Ng2006/>
* Lifestyle modification
** Frequently stressed individuals should consider therapy, or joining a [[support group]].

==Prognosis==
In general, PVCs are harmless. For patients with more than 1,000 PVCs per day, the risk of developing left ventricular systolic dysfunction after 5 years follow-up is low. Frequent PVCs may increase the risk of developing cardiomyopathy, which can greatly impair heart function. A PVC burden greater than 10% is the minimal threshold for development of PVC-induced cardiomyopathy. The risk is higher with a PVC burden greater than 20%. PVC burden often decreases spontaneously over time.<ref>{{Cite journal |last=Zeppenfeld |first=Katja |last2=Tfelt-Hansen |first2=Jacob |last3=de Riva |first3=Marta |last4=Winkel |first4=Bo Gregers |last5=Behr |first5=Elijah R |last6=Blom |first6=Nico A |last7=Charron |first7=Philippe |last8=Corrado |first8=Domenico |last9=Dagres |first9=Nikolaos |last10=de Chillou |first10=Christian |last11=Eckardt |first11=Lars |last12=Friede |first12=Tim |last13=Haugaa |first13=Kristina H |last14=Hocini |first14=Mélèze |last15=Lambiase |first15=Pier D |date=2022-10-21 |title=2022 ESC Guidelines for the management of patients with ventricular arrhythmias and the prevention of sudden cardiac death |url=https://academic.oup.com/eurheartj/article/43/40/3997/6675633 |journal=European Heart Journal |language=en |volume=43 |issue=40 |pages=3997–4126 |doi=10.1093/eurheartj/ehac262 |issn=0195-668X|hdl=1887/3567457 |hdl-access=free }}</ref>

People who do not have heart disease (with ejection fractions greater than 40%) have the same long-term prognoses as the minority of people without PVCs on the 24 hours. Emerging data also suggest that very frequent ventricular ectopy may be associated with cardiomyopathy through a mechanism thought to be similar to that of chronic right ventricular pacing associated cardiomyopathy. For patients with underlying chronic structural heart disease and complex ectopy, mortality is significantly increased.<ref name="keany2" />

In [[meta-analysis]] of 11 studies, people with frequent PVCs (≥ once during a standard electrocardiographic recording or ≥30 times over a 1-hour recording) had risk of cardiac death twice as great as that of participants with occasional PVCs. Although most researchers attempted to exclude high-risk subjects, such as those with histories of cardiovascular disease, they did not test participants for underlying structural heart disease.<ref>{{cite journal|last1=Ataklte|first1=F|last2=Erqou|first2=S|last3=Laukkanen|first3=J|last4=Kaptoge|first4=S| title=Meta-analysis of ventricular premature complexes and their relation to cardiac mortality in general populations.|journal=The American Journal of Cardiology|date=15 October 2013|volume=112|issue=8|pages=1263–70|pmid=23927786|doi=10.1016/j.amjcard.2013.05.065}}</ref>

==Epidemiology==
Single PVCs are common in healthy persons. When 24-hour ambulatory monitoring is used, up to 80 percent of apparently healthy people have occasional PVCs.<ref>{{Cite web|title=Medline ® Abstract for Reference 1 of 'Premature ventricular complexes: Clinical presentation and diagnostic evaluation'|url=https://www.uptodate.com/contents/premature-ventricular-complexes-clinical-presentation-and-diagnostic-evaluation/print}}</ref> Rates vary by age with extremely rare for those under the age of 11 and extremely common in those older than 75 years.<ref>{{Cite journal|last1=Cha|first1=Yong-Mei|last2=Lee|first2=Glenn K.|last3=Klarich|first3=Kyle W.|last4=Grogan|first4=Martha|date=February 2012 |title=Premature Ventricular Contraction-Induced Cardiomyopathy|journal=Circulation: Arrhythmia and Electrophysiology|volume=5|issue=1|pages=229–36|doi=10.1161/CIRCEP.111.963348|doi-access=free |issn=1941-3149|pmid=22334430}}</ref> These differences may be due to rates of high blood pressure and atherosclerosis, which are more easy to find in older persons.<ref name="Kulick2">{{Cite web |last=Kulick |first=David Lee |date=23 March 2016 |editor-last=Shiel |editor-first=William C. Jr. |url=http://www.medicinenet.com/premature_ventricular_contractions/page2.htm |title=Premature Ventricular Contractions (PVCs, PVC): What happens during a premature ventricular contraction? |access-date=2017-02-21 |website=MedicineNet}}</ref> In 101 people free of heart disease during 24 hours Holter monitoring, 39 had at least 1 PVC, and 4 at least 100. Heart disease was excluded after physical examination, chest x-ray, [[ECG]], [[echocardiography]], maximal [[exercise stress test]], right- and left-heart [[catheterization]] and coronary [[angiography]].<ref>{{cite journal|last2=McCrone|first2=K.|last3=Moreyra|first3=A.E. |last4=Gotzoyannis|first4=S.|last5=Aglitz|first5=N.M. |last6=Natarajan|first6=N.|last7=Kuo|first7=P.T. |date=June 1981|title=Premature ventricular complexes in the absence of identifiable heart disease|journal=Circulation|volume=63|issue=6|pages=1351–56|doi=10.1161/01.CIR.63.6.1351|doi-access=free|last1=Kostis|first1=J.B. |pmid=7226480}}</ref> In 122,043 United States Air Force flyers and cadet applicants during approximately 48 seconds of ECG 0.78% (952 males) had PVC within all age groups, but with increased incidence with increasing age.<ref>{{cite journal|last2=Lamb|first2=Lawrence E. |date=June 1962|title=Electrocardiographic Findings in 122,043 Individuals|journal=Circulation|volume=25|issue=6|pages=947–61|doi=10.1161/01.CIR.25.6.947|doi-access=free|pmid=13907778|last1=Hiss|first1=Roland G.}}</ref> Ventricular ectopy is more prevalent in men than in women of the same age; data from large, population-based studies indicate that the prevalence is less for young white women without heart disease and greater for older African American individuals with hypertension.<ref name="keany2" />

==References==
{{Reflist}}

==Further reading==
{{refbegin}}
* {{cite book |last1=Levy |first1=Matthew N. |last2=Pappano |first2=Achilles J. |title=Cardiovascular physiology |url=https://archive.org/details/cardiovascularph2007levy |url-access=registration |edition=9th |year=2007 |isbn=978-0-323-03446-3 |oclc=63660993 |publisher=Mosby Elsevier |location=Philadelphia |series=Mosby physiology monograph series }}
* {{cite book |last1=Nelson |first1=David L. |last2=Cox |first2=Michael M. |title=Lehninger Principles of Biochemistry |edition=5th |year=2008 |url={{google books|5Ek9J4p3NfkC|plainurl=yes}} |isbn=978-0-7167-7108-1 |oclc=957377043 |publisher=W.H. Freeman |location=New York |chapter=Biosignaling |chapter-url={{google books|5Ek9J4p3NfkC|page=419|plainurl=yes}} |via=Google Books |pages=419–484 }}
{{refend}}

== External links ==
{{Medical resources
| ICD11          = {{ICD11|BC61}}, {{ICD11|BC70}}
|   ICD10          = {{ICD10|I|49|3|i|30}}
|   ICD9           = {{ICD9|427.69}}
|   ICDO           =
|   OMIM           =
|   DiseasesDB     = 32412
|   MedlinePlus    =
|   eMedicineSubj  = emerg
|   eMedicineTopic = 773
|   MeshID         = D018879
}}

{{Circulatory system pathology}}

{{DEFAULTSORT:Premature Ventricular Contraction}}
[[Category:Cardiac arrhythmia]]