[Durgical](https://durgical.com/en/) › [DurgiPedia](https://durgical.com/en/durgipedia/) › [Anatomy](https://durgical.com/en/anatomy/) › [Chest](https://durgical.com/en/anatomy/region/chest/) › Left ventricle papillary muscles [Cardiovascular system](https://durgical.com/en/anatomy/system/cardiovascular-system/) · [Chest](https://durgical.com/en/anatomy/region/chest/) # Left ventricle papillary muscles The papillary muscles of the [left ventricle](https://durgical.com/en/anatomy/left-ventricle/) are two muscle pillars that tighten the chordae, keeping the mitral valve shut with each beat. Official name: Superior papillary muscle of left ventricle [See in 3D →](https://durgical.app/?from=durgipedia&lang=en#region=thorax&select=papillary_muscles_lv&side=r) Opens in the Durgical app, no sign-up needed. ## What it is Two finger-like muscles (anterolateral and posteromedial) rising from the left ventricle wall, anchoring the mitral chordae. ## What it does Tighten the chordae as the ventricle squeezes, keeping the mitral valve closed. ## Key points - The anterolateral muscle has a double blood supply (diagonal branches of the left anterior descending artery and marginal branches of the [circumflex artery](https://durgical.com/en/anatomy/circumflex-artery-of-heart/)), so it rarely ruptures - Rupture usually comes in the first week after an infarct, often inferior: sudden acute mitral regurgitation, lung edema and shock; the murmur may be soft or absent - Ischemia without rupture causes milder, sometimes intermittent mitral regurgitation ## Key facts **Where** Left ventricle: anterolateral and posteromedial **Attaches** Each sends chordae to both mitral leaflets **Function** Keep mitral leaflets from everting in systole; posteromedial (single supply, usually PDA) ruptures more often after infarction ## Relations **Lateral** Anterolateral papillary muscle on the anterolateral wall, sending chordae to the lateral halves of both leaflets (anterolateral commissure) **Below** Posteromedial papillary muscle on the inferior wall near the septum, supplied mainly by the [posterior descending artery (PDA)](https://durgical.com/en/anatomy/inferior-interventricular-artery/), to the medial halves of both leaflets **Above** [Mitral anterior leaflet](https://durgical.com/en/anatomy/anterior-leaflet-of-left-atrioventricular-valve/) and [mitral posterior leaflet](https://durgical.com/en/anatomy/posterior-leaflet-of-left-atrioventricular-valve/), through the [chordae tendineae](https://durgical.com/en/anatomy/chordae-tendineae-of-right-atrioventricular-valve/) ## How to find it Opening the left ventricle shows two stout muscles rising from the middle and lower wall, one under each mitral commissure; each sends chords to both leaflets, so one muscle failing affects both. ## On imaging Echocardiography: the parasternal short [axis](https://durgical.com/en/anatomy/axis/) at mid-ventricular level shows both muscles, roughly at 4 and 8 o'clock; a ruptured head appears as a mass flailing into the [left atrium](https://durgical.com/en/anatomy/left-atrium/), clearest on transesophageal echo. ## Common problems - Rupture after a heart attack (rare, an emergency); the posteromedial one is more vulnerable because it has a single blood supply. ## How it is diagnosed Echocardiogram. ## Treatment - Surgical repair: resecting the floppy segment or adding artificial chords. ## Clinical notes - Rupture is one of the three classic mechanical complications of infarction, with free wall and septal rupture, and needs emergency surgery - When the ventricle dilates, the muscles move apart and outward and tether the leaflets, causing functional mitral regurgitation ## Anatomical variants - The number of heads, their origin and their chordal attachments vary: each muscle may be single, bifid or multi-headed ## Development They form from the trabecular meshwork of the embryonic ventricle. If the two do not separate properly, a single muscle receives all the chords (parachute mitral valve), which narrows the valve. ## Related conditions - [Mechanical complications of myocardial infarction](https://durgical.com/en/conditions/mechanical-complications-of-myocardial-infarction/) - [Mitral regurgitation](https://durgical.com/en/conditions/mitral-regurgitation/) - [Myocardial Infarction (Heart Attack)](https://durgical.com/en/conditions/myocardial-infarction/) ## Test yourself Think of the answer, then tap the question to see it. ## Which left ventricle papillary muscle ruptures more often after infarction, and why? The posteromedial muscle, because it has a single blood supply, usually from the posterior descending artery. ## Why does the anterolateral papillary muscle of the left ventricle rarely rupture? It has a double blood supply: diagonal branches of the LAD and marginal branches of the circumflex artery. ## How does papillary muscle rupture after myocardial infarction present? Usually in the first week: sudden acute mitral regurgitation, lung edema and shock; the murmur may be soft or absent. It needs emergency surgery. ## How does a dilated left ventricle cause functional mitral regurgitation? The papillary muscles move apart and outward and tether the mitral leaflets. [Add to my cards (4)](https://durgical.app/estudiar/?add=/en/anatomy/superior-papillary-muscle-of-left-ventricle/) Educational information, not medical advice. For any symptom, see a health professional. ## Its names **Official Latin (TA2)** musculus papillaris superior ventriculi sinistri; musculus papillaris inferior ventriculi sinistri TA2 4067 **Official Spanish (DeCS)** Músculos papilares del ventrículo izquierdo DeCS D010210 **English (TA2)** Superior papillary muscle of left ventricle **Also called** anterior papillary muscle of left ventricle · posterior papillary muscle of left ventricle · musculus papillaris sinister · superolateral papillary muscle ## Related - [Left ventricle](https://durgical.com/en/anatomy/left-ventricle/) - [Chordae tendineae](https://durgical.com/en/anatomy/chordae-tendineae-of-right-atrioventricular-valve/) - [LAD (anterior descending artery)](https://durgical.com/en/anatomy/anterior-interventricular-artery/) - [Circumflex artery](https://durgical.com/en/anatomy/circumflex-artery-of-heart/) - [Right coronary artery](https://durgical.com/en/anatomy/right-coronary-artery/) Sources: Terminologia Anatomica (TA2); [DeCS](https://decs.bvsalud.org/es/ths/resource/?id=10397&filter=ths_termall&q=M%C3%BAsculos%20Papilares); [Anatomy, Thorax, Heart Papillary Muscles](https://www.ncbi.nlm.nih.gov/books/NBK557802/); Anatomy of the Human Body (20th ed.): Development of the Vascular System (Lea & Febiger (Gray's Anatomy, 1918), 1918) · adapted, Public domain. ## **Spotted a mistake?** We are always improving for the community. Tell us what is wrong and our team will review it. Report a mistake Representative model, for educational purposes only. --- Source: https://durgical.com/en/anatomy/superior-papillary-muscle-of-left-ventricle/ License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/anatomy/superior-papillary-muscle-of-left-ventricle/