The heart is a hollow muscular organ located in the mediastinum. It is roughly the size of a clenched fist and has 4 chambers - 2 atria and 2 ventricles separated by interatrial and interventricular septa. The heart receives deoxygenated blood from the superior and inferior vena cavae into the right atrium and pumps it to the lungs for oxygenation before returning oxygenated blood from the left atrium to the left ventricle and out to the aorta for systemic circulation. The heart has surfaces, borders, and measurements described.

16. Primitive
arterial end
Primitive
venous end

17. Primitive
arterial end
(Truncus
arteriosus)
Primitive
venous end

21. Hollow conical muscular organ
Situated in mid. Mediastinum
Covered by pericardium
Size of clenched fist
4 chambers
2 atria - interatrial septum
2 ventricles – intervent. Sep.

22. Rt.atrium receives deoxygenated blood
Via Sup. & Inf. venacavae, and
coronary sinus.
Thru’ Rt. atrioventricular orifice
To – Rt. Ventricle
Ejected to Pulm. Trunk
To Pulm. Capillary plexus for oxygenation
Pulmonary circulation
To Left atrium
Via 4 pulmonary veins
Thru’ Lt. atrioventricular orifice
To Left ventricle
Ejected to ascending aorta for
Systemic circulation

23. Measurements
Apex to base – - 12 cms
Antero-post diameter - 6 cms
Widest transverse diameter 8 to 9 cms
(Equal to one half of diameter of thorax)
Weight male – 280 to 340 gms
female - 230 to 280 gms
Presenting parts
Apex
Base
3 surfaces – Sternocostal, diaphragmatic & Left
3 borders - Right, Inferior & Left

24. Apex
Conical area formed by left ventricle
Directed downwards, forwards and to left
In 5th intercostal space 9 cms from midline
Slightly below & medial to left nipple
Separated from ant.thoracic wall by
left lung & pleura
Base
Posterior surface – fixed part of heart
Quadrilateral in outline
Formed 2/3rds by post. Surface of left atrium &
1/3rd by Rt. Atrium

25. Base

26. Boundaries of base
Above
Bifurcation of Pulm. Trunk
Below
Post. Part of interventricular groove
containing coronary sinus &
anastomosis of Rt. & Lt. coronary arteries.
Rt. Side
Rt. Border of Rt. Atrium
from sup to Inf. Vena cava
Lt. side
Left border of left atrium
from upper to lower Lt. pulm. veins

27. Features of the Base
SVC opens in upper post part of Rt.atrium
IVC opens in lower post part of Rt.atrium
4 Pulm. Veins 2 on each side open in
Post. Surface of Lt. atrium
A shallow vertical inter atrial groove
may be found between 2 atria –
Post. Attachment of Inter atrial septum

28. Right border
Rounded and convex
Formed by Rt. Atrium
Extends from Rt. Side of opening of
SVC to IVC
The border separates base from
Sternocostal surface
Shallow vertical groove accpmanies
Rt. Border – Sulcus terminalis
Corresponds to Crista terminalisin the
Interior of Rt. atrium

29. INCISURA APICIS CORDIS
Inferior Border
Sharp
Separates sternocostal from diaphragmatic
Surfaces
Extends from opening of IVC to apex
Border accompanied by marginal branch
of Rt. Coronary artery and vein
Notch near apex – Incisura apicis cordis
Ant. Interventricular br. of left coronary
curves around it.

30. Left Border
ILL defined convex
Convexity to left and upwards
Separates sternocostal from left surface
Extends from left auricle to apex
Accompanied by marginal br. of Lt.
coronary artery.

31. Sterno – costal surface
Directed forwards and upwards
Separated
From base to by Rt. Border
From diaphragmatic surface by Inf. Border
From Left surface by Left border
Formed by
Ant. Surface of Rt. atrium & its auricle
Part of ant. Surface of Lt. auricle
Ant. Surface of Rt. Ventricle (2/3)
Ant. Surface of left ventricle (1/3)

32. Features of Sterno-Costal Surface
Ant. Part of atrio-ventricular groove
Passes downwards & to right between
Rt. Atrium & Rt. Ventricle
Lodges trunk of Rt. Coronary artery
Ant. Interventricular groove passes
downwards parallel to left border
meets inf. Border at incisura.
The groove lodges ant. Interventricular
br. of Lt. coronary artery & great cardiac vein
Indicates ant. attachment of
interventricular septum

33. Diaphragmatic or Inferior Surface
Flat
Face downwards and backwards
Formed only by ventricles
2/3 left ventricle & 1/3rd by Rt. Ventricle
Separated
From Sternocostal surface by inf. Border
From the base by the post. Part of
Interventricular groove
From left surface by less defined
unnamed border which is backward
Continuation of inferior border

34. Features of Inferior Surface
Post. Interventricular groove runs forwards
along this surface & meets incisura epi.cordis
Groove indicates post. attachment of
Interventricular septum
Groove lodges post. Interventricular br. of
Rt. Coronary artery
Middle cardiac vein
Anastomosis of interventricular
branches of Both coronary arteries

35. Left Surface
Directed upwards backwards and to left
Formed mainly by left ventricle and
Partly by left atrium & Left auricle
Features
Left part of atrioventricular groove
intervenes between Lt. auricle and lt. ventricle
This groove lodges –
Trunk and cicumflex br. of left cor. art.
Termination of great cardiac vein
Commencement of coronary sinus

36. Apex formed by left ventricle
Base formed by 2 atria
Rt. Border formed by Rt. Atrium
Diaphragmatic surface formed by 2 ventricles
Base - 2/3 lt. atrium 1/3 Rt. Atrium
Diaphragmatic surface – 2/3 Lt. ventricle, 1/3 Rt. Ventricle
Sternocostal surface – 2/3 Rt. Ventricle 1/3 Lt. ventricle
From midline 2/3 to left of midline, 1/3 to Rt. Of midline

37. If an elderly in your house suffers from
chest pain
Do not browse net from your cel to verify
which Doctor can diagnose the illness
But; equip yourself with sufficient
Knowledge to save your own
kith and kin first.
Only gratitude you can return to your
“well-wishers”
And it is the ultimate pride and their ambition