What is the function of chordae tendineae?
ANSWER: (B) Prevents regurgitationREF: BRS Anatomy 7th ed page 152, Gray's anatomy 40tn ed chapter 56CHORDAE TENDINEAE (TENDINOUS CORDS)They are fibrous collagenous structures supporting the cusps of the atrioventricular valvesFalse chordae connect papillary muscles to each other or to the ventricular wallincluding the septum, or pass directly between points on the wall (or septum, or both).The true chordae usually arise from small projections on the tips or margins of the apical one-thirds of papillary muscles, but sometimes arise from the bases of papillary muscles or directly from the ventricular walls and the septum. They are attached to various parts of the ventricular aspects or the free margins of the cusps. They have been classified into first-, second-and third-order chordae according to the distance of the attachment from the margins of the cusps.Fan-shaped chordae have a short stem from which branches radiate to attach to the margins (or the ventricular aspect) of the zones of apposition between cusps and to the ends of adjacent cusps. Rough zone chordae arise from a single stem which usually splits into three components that attach to the free margin.True chordae of the mitral valve may be divided into intercusp (or commissural) chordae, rough zone chordae, including the special strut chordae, so-called 'cleft' chordae and basal chordae. Most true chordae divide into branches from a single stem soon after their origin from the apical one-third of a papillary muscle, or proceed as single chordae that divide into several branches near their attachment. Basal chordae, in contrast, are solitary structures passing from the ventricular wall to the mural cusp.Function: Papillary muscles contracts to tightens the chordae tendineae preventing the cusps of the valves from being everted into the atrium by pressure developed by pumping action of the heart. This prevents regurgitation of the ventricular blood into the atrium.
Opens A-V valve
Prevents regurgitation
Helps contraction of papillary muscles
Passes action potential to papillary muscles
Pericardium & Heart