The phrase “heart strings” often describes deep emotional resonance, but it is inspired by real, physical structures inside the human heart. Many people search for the true anatomical name for these fibrous cords that perform a mechanical job required for efficient blood circulation.
The Anatomical Answer
The structures commonly known as “heart strings” are officially named the Chordae Tendineae. These are robust, cord-like tendons made primarily of collagen, giving them immense tensile strength. The Latin name means “tendinous cords.” They serve as tethers for the leaflets of the heart’s atrioventricular (AV) valves. Damage or rupture to these cords can be a serious medical event, such as a rupture of the chordae tendineae.
Structure and Positioning
The Chordae Tendineae are positioned within the heart’s lower chambers, the ventricles. These fibrous strands connect the free edges of the two major atrioventricular (AV) valves to muscular anchors on the ventricular walls. They secure the tricuspid valve on the right and the mitral (bicuspid) valve on the left.
The cords attach the valve leaflets to specialized muscular projections known as papillary muscles. These muscles arise directly from the inner surface of the ventricular walls, providing a stable foundation. The mitral valve typically has a more complex arrangement of cords than the tricuspid valve.
The length and thickness of the cords vary slightly depending on the specific valve and their exact point of insertion on the valve leaflet. These variations ensure the cords allow the leaflets to open fully during diastole, the heart’s filling phase. The cords are categorized based on insertion: marginal (attaching to the free edge) and intermediate (providing support on the ventricular surface).
Function in Blood Circulation
The primary mechanical role of the Chordae Tendineae is to maintain the unidirectional flow of blood during the cardiac cycle. This action is most evident during systole, the contraction phase of the ventricles. As the ventricular muscles squeeze to pump blood out, pressure inside the chambers rises rapidly.
This sudden pressure surge forces the AV valves closed, preventing blood from flowing backward into the atria. The force is so great that it would normally cause the valve leaflets to flip backward, or prolapse. Failure of the valve to withstand this pressure, often due to damaged cords, results in regurgitation, where blood leaks in the wrong direction.
The papillary muscles contract simultaneously with the ventricular walls, pulling on the Chordae Tendineae. This tension acts like guy-wires, holding the valve leaflets firmly closed and bracing them against the high pressure gradient. By preventing prolapse, the cords ensure blood is directed solely into the appropriate exit arteries, maintaining cardiac output.
The Metaphorical Connection
The common phrase “tugging at the heart strings” is a direct linguistic echo of the anatomical structure. Early anatomists observed these fine, tendon-like structures, recognizing their visual similarity to strings or cords. This observation inspired the metaphorical use of the phrase, linking the physical cords to the seat of human emotion.
The metaphor suggests that a powerful emotional stimulus is physically pulling these internal cords, creating a deeply felt response. This connection between the visible anatomy and emotional experience highlights how the heart has long been understood as the center of feeling, blending biology with poetry.