Editing Heart failure (section)

=== Classification ===
==== "Left", "right" and mixed heart failure ====
One historical method of categorizing heart failure is by the side of the heart involved (left heart failure versus right heart failure). Right heart failure was thought to compromise blood flow to the lungs compared to left heart failure compromising blood flow to the [[aorta]] and consequently to the brain and the remainder of the body's systemic circulation. However, mixed presentations are common, and left heart failure is a common cause of right heart failure.<ref>{{cite web|url=http://www.ucsfhealth.org/conditions/heart_failure/signs_and_symptoms.html|title=Heart Failure: Signs and Symptoms|publisher=UCSF Medical Center|url-status=live|archive-url=https://web.archive.org/web/20140407080141/http://www.ucsfhealth.org/conditions/heart_failure/signs_and_symptoms.html|archive-date=7 April 2014|df=dmy-all}}</ref>

==== By ejection fraction ====
A more accurate classification of heart failure type is made by measuring [[ejection fraction]], or the proportion of blood pumped out of the heart during a single contraction.<ref name="HRS2014">{{cite web|url=http://www.hrsonline.org/Patient-Resources/The-Normal-Heart/Ejection-Fraction#axzz31jSSC7Uo|title=Ejection Fraction|website=Heart Rhythm Society|url-status=live|archive-url=https://web.archive.org/web/20140502123346/http://www.hrsonline.org/Patient-Resources/The-Normal-Heart/Ejection-Fraction#axzz31jSSC7Uo|archive-date=2 May 2014|access-date=7 June 2014|df=dmy-all}}</ref> Ejection fraction is given as a percentage with the normal range being between 50 and 75%.<ref name="HRS2014" /> The types are:
# [[Heart failure with reduced ejection fraction]] (HFrEF): Synonyms no longer recommended are "heart failure due to left ventricular systolic dysfunction" and "systolic heart failure".<ref name="pmid35460242">{{cite journal |vauthors=Santulli G, Wang X, Mone P |title=Updated ACC/AHA/HFSA 2022 guidelines on heart failure: what is new? From epidemiology to clinical management |journal=Eur Heart J Cardiovasc Pharmacother |volume=8 |issue=5 |pages=e23–e24 |date=August 2022 |pmid=35460242 |doi=10.1093/ehjcvp/pvac029 |pmc=9366633 |url=|doi-access=free }}</ref> HFrEF is associated with an ejection fraction less than 40%.<ref>{{cite web|url=http://www.heart.org/HEARTORG/Conditions/HeartFailure/SymptomsDiagnosisofHeartFailure/Ejection-Fraction-Heart-Failure-Measurement_UCM_306339_Article.jsp|title=Ejection Fraction Heart Failure Measurement|date=Feb 11, 2014|website=American Heart Association|url-status=live|archive-url=https://web.archive.org/web/20140714140152/http://www.heart.org/HEARTORG/Conditions/HeartFailure/SymptomsDiagnosisofHeartFailure/Ejection-Fraction-Heart-Failure-Measurement_UCM_306339_Article.jsp|archive-date=14 July 2014|access-date=7 June 2014|df=dmy-all}}</ref>
# Heart failure with mildly reduced ejection fraction (HFmrEF), previously called "heart failure with mid-range ejection fraction",<ref name="HFmrEF_ESC2021">{{Cite journal |title=2021 ESC Clinical Practice Guidelines for the diagnosis and treatment of acute and chronic heart failure |url=https://www.escardio.org/Congresses-Events/ESC-Congress/Congress-resources/Congress-news/2021-esc-clinical-practice-guidelines-for-the-diagnosis-and-treatment-of-acute-a |date=2021-08-27 |access-date=2023-02-06 |website=European Society of Cardiology |language=en |archive-date=6 February 2023 |archive-url=https://web.archive.org/web/20230206211913/https://www.escardio.org/Congresses-Events/ESC-Congress/Congress-resources/Congress-news/2021-esc-clinical-practice-guidelines-for-the-diagnosis-and-treatment-of-acute-a |url-status=live }}</ref> is defined by an ejection fraction of 41–49%.<ref name="HFmrEF_ESC2021"/>
# [[Heart failure with preserved ejection fraction]] (HFpEF): Synonyms no longer recommended include "diastolic heart failure" and "heart failure with normal ejection fraction."<ref name="NICE2010chp1" /><ref name=":0" /> HFpEF occurs when the left ventricle contracts normally during systole, but the ventricle is stiff and does not relax normally during diastole, which impairs filling.<ref name="NICE2010chp1" />
# Heart failure with recovered ejection fraction (HFrecovEF or HFrecEF): patients previously with HFrEF with complete normalization of left ventricular ejection (≥50%).<ref>{{cite journal | vauthors = Bozkurt B, Hershberger RE, Butler J, Grady KL, Heidenreich PA, Isler ML, Kirklin JK, Weintraub WS | title = 2021 ACC/AHA Key Data Elements and Definitions for Heart Failure: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Data Standards (Writing Committee to Develop Clinical Data Standards for Heart Failure) | journal = Circulation: Cardiovascular Quality and Outcomes | volume = 14 | issue = 4 | pages = e000102 | date = April 2021 | pmid = 33755495 | pmc = 8059763 | doi = 10.1161/HCQ.0000000000000102 }}</ref><ref>{{cite journal | vauthors = Devgun JK, Kennedy S, Slivnick J, Garrett Z, Dodd K, Derbala MH, Ortiz C, Smith SA | title = Heart failure with recovered ejection fraction and the utility of defibrillator therapy: a review | journal = ESC Heart Failure | volume = 9 | issue = 1 | pages = 1–10 | date = February 2022 | pmid = 34953039 | pmc = 8787956 | doi = 10.1002/ehf2.13729 }}</ref>

Heart failure may also be classified as acute or chronic. Chronic heart failure is a long-term condition, usually kept stable by the treatment of symptoms. [[Acute decompensated heart failure]] is a worsening of chronic heart failure symptoms, which can result in [[acute respiratory distress]].<ref name="Jessup2009">{{cite journal | vauthors = Jessup M, Abraham WT, Casey DE, Feldman AM, Francis GS, Ganiats TG, Konstam MA, Mancini DM, Rahko PS, Silver MA, Stevenson LW, Yancy CW | title = 2009 focused update: ACCF/AHA Guidelines for the Diagnosis and Management of Heart Failure in Adults: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines: developed in collaboration with the International Society for Heart and Lung Transplantation | journal = Circulation | volume = 119 | issue = 14 | pages = 1977–2016 | date = April 2009 | pmid = 19324967 | doi = 10.1161/CIRCULATIONAHA.109.192064 | doi-access =  }}</ref> [[High-output heart failure]] can occur when there is increased cardiac demand that results in increased left ventricular diastolic pressure which can develop into pulmonary congestion (pulmonary edema).<ref name="ReferenceA">{{DorlandsDict|nine/000953450|high-output heart failure}}</ref>

Several terms are closely related to heart failure and may be the cause of heart failure, but should not be confused with it. [[Cardiac arrest]] and [[asystole]] refer to situations in which no cardiac output occurs at all. Without urgent treatment, these events result in sudden death. Myocardial infarction ("Heart attack") refers to heart muscle damage due to insufficient blood supply, usually as a result of a blocked [[coronary artery]]. Cardiomyopathy refers specifically to problems within the heart muscle, and these problems can result in heart failure.<ref name="pmid36356656">{{cite journal |vauthors=Somma V, Ha FJ, Palmer S, Mohamed U, Agarwal S |title=Pacing-induced cardiomyopathy: A systematic review and meta-analysis of definition, prevalence, risk factors, and management |journal=Heart Rhythm |volume= 20|issue= 2|pages= 282–290|date=October 2022 |pmid=36356656 |doi=10.1016/j.hrthm.2022.09.019 |s2cid=253409509 |url=}}</ref> Ischemic cardiomyopathy implies that the cause of muscle damage is coronary artery disease. [[Dilated cardiomyopathy]] implies that the muscle damage has resulted in enlargement of the heart.<ref name="pmid34685747">{{cite journal |vauthors=Mages C, Gampp H, Syren P, Rahm AK, André F, Frey N, Lugenbiel P, Thomas D |title=Electrical Ventricular Remodeling in Dilated Cardiomyopathy |journal=Cells |volume=10 |issue=10 |date=October 2021 |page=2767 |pmid=34685747 |pmc=8534398 |doi=10.3390/cells10102767 |url=|doi-access=free }}</ref> [[Hypertrophic cardiomyopathy]] involves enlargement and ''thickening'' of the heart muscle.<ref name="pmid30219395">{{cite journal |vauthors=Tower-Rader A, Mohananey D, To A, Lever HM, Popovic ZB, Desai MY |title=Prognostic Value of Global Longitudinal Strain in Hypertrophic Cardiomyopathy: A Systematic Review of Existing Literature |journal=JACC Cardiovasc Imaging |volume=12 |issue=10 |pages=1930–1942 |date=October 2019 |pmid=30219395 |doi=10.1016/j.jcmg.2018.07.016 |url=|doi-access= |s2cid=52280408 }}</ref>