The chordae tendinae are cord-like tendons that connect the papillary muscles to the tricuspid valve and the mitral valve in the heart.
When the right ventricle of the heart contracts, the blood pressure pushes the tricuspid valve which closes and prevents a backflow of blood into the right atrium. The chordae tendineae prevents the flaps from being everted into the right atrium. Similarly, these cord-like tendons hold in position other flaps like the bicuspid or mitral valve.
right heart: (vena cavae, coronary sinus) → right atrium (fossa ovalis) → tricuspid valve → right ventricle → pulmonic valve → (pulmonary artery and pulmonary circulation)
left heart: (pulmonary veins) → left atrium → mitral valve → left ventricle → aortic valve → (aorta, aortic sinus and systemic circulation)
pericardium | epicardium | endocardium | myocardium
conduction system: cardiac pacemaker | Purkinje fibers | bundle of His | SA node | AV node