Download Anatomy of the Heart

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RSPT 1207 – Cardiopulmonary A & P
The Cardiovascular System
Anatomy of the Heart
Lecture Notes
Reference & Reading: Egan’s Chapter 9
I. The Heart
a. Is a hollow, muscular organ
b. Located behind the sternum, approximately 2/3 of the heart is lies to the left of
the sternum
c. Sulci
Coronary sulcus
Anterior & posterior sulci
II. Pericardium
a. Parietal pericardium
b. Visceral pericardium
c. Pericardial fluid
d. Pericarditis
III. Heart wall – Three layers:
a. Outer epicardium
b. Middle myocardium
c. Inner endocardium
IV. Support of the heart
a. Provided by four AV rings
b. Anuli fibrosi cordis
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V. The Atria
a. Interatrial septum
b. Right atrium
c. Auricle
VI. The Ventricles
a. Make up bulk of heart’s muscle mass
b. Do most of the pumping involved in circulation
c. L ventricle
d. R ventricle
e. Left ventricular aid
f. Interventricular septum
VII. AV valves of the Heart
a. AV valves located between atria & ventricles
Tricuspid valve
Bicuspid (mitral) valve
AV valves close on contraction of the ventricles (systole) preventing
backflow into the atria
AV valves are connected to papillary muscle of the endocardium by
chordate tnedineae cordis – any damage to either can impair function
of the AV valves
b. Common valve problems
Regurgitation
Stenosis
VIII. Semilunar Valves
a. Pulmonary valve
b. Aortic Valve
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IX. Coronary Circulation
a. Coronary arteries
Left coronary artery divides into 2 braches
1. Anterior desecending brach
2. Circumflex branch
Right coronary artery - begins at the aorta and diagonally to R across
the coronary sulcus; moves along right ventricle into many branches
1. Posterior Descending branch
2. Branches of R coronary artery supply:
a. Anterior & posterior portions of ventricular myocardium
b. R atrium
c. Sinus node
d. Posterior third of interventricular septum
e. Par of base of R ventricle
Coronay Veins
1. Coronary Sinus
2. Thebesian veins
X. Properties of Heart Muscle
a. Excitability
b. Inherent rhythmicity (automatic)
Comes from specialized tissues mainly pacemaker or nodal tissue
Electrical impulse from other than pacemaker tissue may result in
cardiac arrthymias
c. Conductivity
Like smooth muscle to move involuntarily
Variances in impulses to ensure synchronization of cardiac chambers
d. Contractility – primary function of myocardium when responding to an
impulse
Refractory period