Heart Anatomy <3

Benish IslamCoordinator/ Lecturer Surgical IPMS

MKU

Fibrous and serous pericardium

Surfaces of heart

Surfaces of heartSternocostal surface: formed by rt. Atrium

and rt. Ventricle which are separated by arterioventricular groove.

Rt. Border:rt. Atrium , Lt border: lt atrium and part of lt.auricle. Rt and lt ventricle separated by interventricular groove.Diaphragmatic surface: Formed by rt.and lt.

ventricles. Separated by post. Interventricular groove.

Inf. Surface of rt. Atrium into which inf. Vena cava opens is also involvedBase of heart: post. Surface. Formed by lt.

atrium,4 pulmonary veins opens here.Apex of heart: formed by lt. ventricle,

directed downward forward to left. Lies at level of 5th intercostal space. Its 3.5 inch away from midline. Apex beat palpated in living patient.

Chambers of heart• Rt Atrium• Rt.

Ventricle• Lt. Atrium• Lt Ventricle

Rt. AtriumConsist of main cavitySmall put pouching-

auricleAt junction of rt.

Atrium and rt. Auricle there is vertical groove Sulcus terminalis, which on inside form a ridge, Crista terminalis.

Part of trium in front of ridge is rough or trabeculated by muscle fiber bundles, musculi pectinati.

Openings into rt. AtriumSuperior vena cava: opens into upper part

of rt. Atrium (returns blood to heart from upper half of body)

Inf. Vena cava: opens into lower part of atrium (returns blood to heart from lower part of body)

Coronary sinus: Drains blood from heart wall,opens to rt. Atrium between inf. Vena cava and arterioventricular orifice.

Rt. Arterio ventricular orifice: anteriot to vena cava and guarded by Tricuspid valves

Rt. ventricleWall of rt. Ventricle is much thicker than atrium.Ventricle wall has projecting ridges,trabeculae

carnea which has 3 types:1.Papillary muscles,Chordae tendineae (Fibrous chords)2.Moderarotor band (part of conducting system)3. Prominent ridgesTricuspid valve: guards arterio ventricular orifice,3

cusps formed by endo metrium. Pulmonary valve: pulomnary orifice.At root of pulmonary trunk: dilations called aortic

valve.

Aortic Valve

Lt. AtriumConsist of main cavity and lt. auricleForms grater part of base of posterior

surfaceOpenings: total 4 pulmonary veins,2 from

each lungs.Left atrioventricle is guarded by mitral

valve

Left ventricle:It communicates with lt. atrium through

atrioventricular orifice.And with aorta throug aortic orifice.

Part of ventricle below the aortic orifice called aortic vestibule.

Mitral valves guards atrio ventricular orifice.it has 2 cusps ie. anterior and posterior.

Aortic valve at aiotic orifice.Behind each cusp aortic wall buldges to

form aortic sinuses.Anterior aortic sinus gives origin to

coronary arteryLt. post. Sinus gives origin to lt. coronary

artery.

Conducting system of heartNormal heart rhythm: 70-90 beats per

minuteContraction rhythm starts spontaneously in

conducting system and impulse travels to different regions in heart.

Atria (together) contracts first with a slight delay followd by ventricle contraction.

Conducting system comprises special cardiac muscle present in sinuatrial node,aterioventricular node, atrioventricular bundle.

Purkinje fibers ( specialised muscle fibre from coducting system)