Papillary muscle

(anatomy) Any of the muscular eminences in the ventricles of the heart from which the chordae tendineae arise.

Nipple-shaped projections of ventricular muscle to which the tendinous cords (see chordae tendinae) of the atrioventricular valves are attached. Contractions of the papillary muscles assist the tendinous cords in preventing the valves from being thrust out into the atrial cavity during ventricular systole.

Any of the group of myocardial bundles that terminate in the tendinous cords that attach to the cusps of the atrioventricular valves.

The noun has one meaning:

Meaning #1: any of several muscles associated with the atrioventricular valves

Papillary muscle
Interior of right side of heart. Papillary muscles labeled in purple.
Diagram showing relations of opened heart to front of thoracic wall. Ant. Anterior segment of tricuspid valve. A O. Aorta. A.P. Anterior papillary muscle. In. Brachiocephalic artery (Innominate). L.C.C. Left common carotid artery. L.S. Left subclavian artery. L.V. Left ventricle. P.A. Pulmonary artery. R.A. Right atrium. R.V. Right ventricle. V.S. Ventricular septum.
Latin	musculus papillaris
Gray's	subject #138 532

In anatomy, the papillary muscles of the heart serve to limit the movements of the mitral and tricuspid valves. These muscles contract to tighten the chordae tendineae, which in turn prevent inversion. This occurs in response to pressure gradients. Instead they brace the valves against the high pressure, preventing regurgitation of ventricular blood back into the atrial cavities.

Additional images

Section of the heart showing the ventricular septum.

Schematic representation of the atrioventricular bundle of His.

Heart normal short axis echo

Heart short axis view papillary

External links

• papillary+muscle at eMedicine Dictionary
• SUNY Labs 20:19-0106 - "Heart: The Right Atrioventricular (Tricupsid) Valve" (anterior, posterior, septal papillary muscles)
• SUNY Labs 20:26-0105 - "Heart: The Left Atrioventricular (Mitral) Valve" (anterior, posterior papillary muscles)
• -1368719301 at GPnotebook
• Bioweb at UWLAX Human heart model (left internal anatomy)
• Atlas of anatomy at UMich ht_rt_vent - "Right atrioventricular bundle branch, anterior view"
• Definition of Papillary muscle
• MedicineNet Search Results

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v • d • e Anatomy of torso, cardiovascular system: heart (TA A12.1, GA 5.524) General Surface base · apex · grooves (coronary/atrioventricular, interatrial, anterior interventricula, posterior interventricular) · surfaces (sternocostal, diaphragmatic) · borders (right, left) Internal atria (interatrial septum, musculi pectinati) · ventricles (interventricular septum, trabeculae carneae, chordae tendineae, papillary muscle) · valves · cusps · Atrioventricular septum cardiac skeleton (fibrous trigone, fibrous rings) Chambers Right heart (vena cavae, coronary sinus) → right atrium (atrial appendage, fossa ovalis, limbus of fossa ovalis, crista terminalis, valve of the inferior vena cava, valve of the coronary sinus) → tricuspid valve → right ventricle (conus arteriosus, moderator band/septomarginal trabecula)  → pulmonary valve → (pulmonary artery and pulmonary circulation) Left heart (pulmonary veins) → left atrium (atrial appendage) → mitral valve → left ventricle → aortic valve (aortic sinus) → (aorta and systemic circulation) Layers Endocardium Heart valves Myocardium Conduction system: Cardiac pacemaker · SA node · AV node · bundle of His · Purkinje fibers Pericardial cavity Pericardial sinus Pericardium fibrous pericardium (Sternopericardiac ligaments) · serous pericardium (epicardium/visceral layer) · Fold of the left vena cava heart navs: anat/physio/dev, noncongen/congen/neoplasia, symptoms+signs/eponymous, proc

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