papillary muscles


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papillary muscles

The finger-like muscular processes arising from the floors of the VENTRICLES of the heart to which are attached the strings (chordae tendineae) that tether the cusps of the atrioventricular valves.
Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005
References in periodicals archive ?
Effects of increased calcium concentration on myocardial function in papillary muscles from control (white bars; n=11) and obese (black bars; n=11) rats after 33 weeks.
Further, a previous study showed that the insertion sites were abundant with Purkinje fibers and cholinesterase-containing nerve fascicles, which gave rise to the possibility that a mechanical stretch of RV might influence its electrophysiological properties.[8] In addition, the APM, also a potential substrate for idiopathic ventricular arrhythmia, is anatomically connected with MB, and ablation of the ventricular insertion to papillary muscle proved a perfect target for PM-origin ventricular arrhythmia.[9]
Type 1 (66%) extends between posteromedial papillary muscle and ventricular septum, type 2 (12%) between anterolateral papillary muscle and posteromedial papillary muscle, type 3 (11%) between anterolateral papillary muscle and ventricular septum, type 4 (9%) between left ventricular free wall and ventricular septum, and type 5(1%) between one left ventricular free wall and another left ventricular free wall [16].
To obtain a broad scope of quantitative data to dissect contractile function and dysfunction, two of the three main mechanisms utilized in vivo to physiologically modify force of contraction, frequency-dependent activation, and [beta]-adrenergic stimulation were assessed in mouse papillary muscles under near physiological conditions as previously mentioned [22-24].
Morphologically, the papillary muscles can be classified as conical, mammillated, flat topped, grooved, stepped, wavy, arched, sloped, saucerised, two tiered, interlinked, parallel, V, Y or H-shaped.
Papillary muscle thickening and shortening probably contributed to the tricuspid and mitral regurgitation.
In our study, the remodeling of myocardium both after coronary artery occlusion (the II group) and after development of hyperglycemia (the III group) led to a change in inotropic reaction of papillary muscles on extrasystolic actions compared to the control group (Figure 1).
The longitudinal view exposes a papillary muscle (red rectangle) extending from the left endocardial surface to the aortic valve.
Several pathologies may result in anatomical and functional abnormalities of the papillary muscles such as ischemia, fibrosis and rupture.
(1) The coarse and broad trabeculae that are seen in LVNCC take the place of the normally conspicuous anterior and posterior papillary muscles that anchor the chordae tendinae of the three cusps of the mitral valve.
Transthoracic echocardiogram showed the right sided systemic ventricle to be rounded with prominent trabeculae and diminutive papillary muscles. The right sided ventricle had smooth wall and well-formed papillary muscles.

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