Valves

Valves Four cardiac valves Two categories One way blood flow Based on location in heart Atrioventricular Valves Mitral and Tricuspid Semilunar valves Aortic and Pulmonic

Atrioventricular valves Located between Atria and Ventricles Diastolic valves-open during diastole Right Side Tricuspid valve Largest of cardiac valves Three leaflets Closer to apex Left Side Mitral valve Two leaflets Smiley face Diastolic Valves

Components of AV Valves Annulus Fibrous ring Superior edge of leaflets Anchors between atria and ventricles Leaflets Made of valvular tissue Attach to Chordae Tendineae Chordae Tendineae Attach to papillary muscles Papillary Muscles Anchor the AV valve apparatus to ventricular walls

Components of Mitral Valve Anterior Leaflet Posterior Leaflet Commissures Annulus Chordae Tendineae

Normal Mitral valve

Anterior Leaflet Semi-circular shape Attaches to two fifths of the annular circumference. Three segments A1 (anterior segment) A2 (middle segment) A3 (posterior segment) Aortic –mitral curtain Area of tissue between the mitral vavle and left and non-coronary cusp of aortic valve. (all same tissue)

Posterior Leaflet Quadrangular shape and is Attached to approximately three fifths of the annular circumference. Two well defined indentations which divides the leaflet into three individual scallops identified as P1 (anterior or medial scallop), P2 (middle scallop), and P3 (posterior or lateral scallop). The three corresponding segments of the anterior leaflet are A1 (anterior segment), A2 (middle segment), and A3 (posterior segment)1. .

Commissures The commissures define a distinct area where the anterior and posterior leaflets come together at their insertion into the annulus.

Commisures

Annulus Marks the hinge line of the leaflets D shaped The straight border accommodates the aortic valve Remember the MV and AoV same tissue so the fibrousness of the annulus is together with AoV too. This forms right and left trigone. (triangular area of fibrous tissue) AV node forms in right trigone.

Trigones L trigone R Trigone

Papillary Muscles Normally arise from apex and middle third of LV Anteriolateral papillary larger Fed by LAD or left circumflex artery Posteriomedial papillary smaller Fed by right coronary artery

Chordae Tendineae True False Small fibrous strings that originate either from the apical portion of the papillary muscles or directly from the ventricular wall and insert into the valve leaflets or the muscle. False False chordae can connect 2 papillary muscles, connect a papillary muscle to the ventricular wall, or connect points on the ventricular walls.

Tricuspid Valve Three valves Anterior (or infundibular) cusp Largest Cusp Between AV orifice and conus arteriosus (LVOT) Posterior (marginal) Cusp Next largest Post to margin of right ventricle Septal (medial) Cusp attached to the right and left fibrous trigones and the atrial and ventricular septa.

Normal TV

Papillary Muscles Anterior, Posterior, Septal Papillary muscles Anterior- largest Posterior often bifid or trifid Septal-smallest True chordae Tendineae The true chordae typically originate from the apical third of the papillary muscle but can originate from the ventricular walls, as is the case for the septal leaflet. True chordae will only connect papillary muscles to leaflets False Chordae Tendineae False chordae can connect 2 papillary muscles, connect a papillary muscle to the ventricular wall, or connect points on the ventricular walls.

False Chordae (tendon)

Semilunar Valves Right Side Left Side Pulmonic valve Aortic valve Systolic Valves-Open in systole Made up of 3 pocket- like cusps surrounded by annulus Smaller than AV valves

Pulmonic valves Three Cusps Not supported by septum Anterior (non septal) Right Left Not supported by septum Nodes at center of each cusp In RVOT view the anterior and right cusps can be seen

Aortic Valve Three Cusps right cusp left cusp noncoronary cusp Each cusp has a nodule which when closed meet in the middle Nodule of Arantius

Aortic Sinus Dilation of area just above AoV Three Sinuses Left Anterior Rise to left coronary artery Right Anterior Rise to right coronary artery Posterior No vessels –non coronary sinsus Also Known As Sinus of Valsalva Sinus of Morgani Sinus of Otto Petit’s Sinus

In Review