8th Lecture Pericardium and Heart 2014

Pericardium

The heart lies enclosed within pericardial membranes
Fibrous pericardium (pericardial sac) – outer layer of dense CT that protects & anchors
Serous pericardium – double layered membrane with “pericardial fluid” between
Parietal pericardium – lines the pericardial sac
Visceral pericardium – covers the heart; also known as the “epicardium”

Pericardium

Double walled sac around heart composed of:
Superficial fibrous pericardium
Deep two-layer serous pericardium
Parietal layer lines internal surface of fibrous pericardium
Visceral layer (AKA epicardium) lines surface of heart
Parietal and visceral layers separted by fluid filled pericardial cavity

Pericardium

Protects and anchors heart
Prevents overfilling
Provides friction free environment for heart

Constituents of Heart Wall

Epicardium: the visceral layer of serous pericardium
Myocardium: muscle layer
Fibrous skeleton: interlacing, criss-crossing layer of connective tissue
Endocardium: endothelial layer of inner myocardial surface

Cardiovascular SystemThe HeartAnatomy

The Cardiovascular system is comprised of the heart, blood vessels, & blood
The heart acts as a “pump”, creating pressure which causes blood to move through the blood vessels of the body, allowing O2 & nutrients to be distributed to, & wastes removed from, body tissues

Cardiac Anatomy

Atria

Receiving chambers of heart
Each has an auricle
Pectinate muscles


Ventricles
Discharging chambers of heart
Characterized by papillary muscles and trabeculae carneae muscles

Overview of Blood Flow

Right Atrium
Tricuspid Valve
Right Ventricle
Pulmonary Valve
Pulmonary Artery
Lungs
Pulmonary Veins
Left Atrium
Mitral Valve
Left Ventricle
Aortic Valve
Aorta
Systemic Circulation




Anatomical Features of the Heart
The heart lies within the mediastinum of the thoracic cavity
Hollow muscular organ with four internal chambers
(2) atria (lt. atrium & rt. atrium)- receive blood from veins
(2) ventricles (lt. ventricle & rt. ventricle)- pump blood into arteries
Superior aspect of heart is the “base” (3rd intercostal space/sternal angle), where the blood vessels attach; Inferior is the “apex” (5th intercostal space), which rests on the relaxed diaphragm

External Features

Auricles
Coronary sulcus – contains the coronary sinus
Anterior interventricular sulcus – contains coronary vessels
Posterior interventricular sulcus – contains coronary vessels

Layers of Heart Wall

Epicardium (visceral pericardium)
Myocardium
Endocardium

Human Anatomy, 3rd edition

Prentice Hall, © 2001
Internal Anatomy of the Heart
Chambers of the heart
Right & left atrium
Separated by the interatrial septum
Right & left ventricle
Separated by the interventricular septum

Human Anatomy, 3rd edition

Prentice Hall, © 2001
Structure of the Heart Wall

Epicardium = “upon the heart” = visceral pericardium

Dense fibrous connective tissue
Myocardium is the middle layer
Cardiac muscle
Endocardium = “inside the heart”
Simple squamous epithelium

Human Anatomy, 3rd edition

Prentice Hall, © 2001
The Great Vessels
Superior & inferior vena cava
Return blood from body to right atrium
Coronary Sinus
Returns blood from heart wall to right atrium

Human Anatomy, 3rd edition

Prentice Hall, © 2001
The Great Vessels
Pulmonary veins
Return blood (oxygenated) from lungs to left atrium
Aorta
Takes blood from left ventricle to body
Pulmonary artery
Takes blood (deoxygenated) from right ventricle to lungs

Cardiac muscle tissue

Rt Atrium
Lt Atrium

Pectinate muscles

SVC
IVC
Coronary sinus (opening)
Deoxygenated blood
Pulmonary veins
Oxygenated blood
Tricuspid valve

Bicuspid (mitral) valve

Chordae tendoneae
Papillary muscle

Chordae tendoneae

Papillary muscle


Interatrial septum

Fossa ovalis

Atrioventricular (AV) valves

Tricuspid
Bicuspid

Rt ventricle

Lt ventricle


Interventricular septum

Trabeculae carneae

Aorta

Aortic semilunar valve

Pulmonary semilunar valve

Pulmonary trunk

Pulmonary artery

Ligamentum arteriosum

Brachiocephalic trunk

Left common carotid artery

Left subclavian artery

Human Anatomy, 3rd edition

Prentice Hall, © 2001
Internal Anatomy of the Heart
Chambers of the heart
Right & left atrium
Separated by the interatrial septum
Right & left ventricle
Separated by the interventricular septum

Human Anatomy, 3rd edition

Prentice Hall, © 2001
Structure of the Heart Wall

Epicardium = “upon the heart” = visceral pericardium

Dense fibrous connective tissue
Myocardium is the middle layer
Cardiac muscle
Endocardium = “inside the heart”
Simple squamous epithelium

Human Anatomy, 3rd edition

Prentice Hall, © 2001
The Great Vessels
Superior & inferior vena cava
Return blood from body to right atrium
Coronary Sinus
Returns blood from heart wall to right atrium

Human Anatomy, 3rd edition

Prentice Hall, © 2001
The Great Vessels
Pulmonary veins
Return blood (oxygenated) from lungs to left atrium
Aorta
Takes blood from left ventricle to body
Pulmonary artery
Takes blood (deoxygenated) from right ventricle to lungs





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The End