Anatomy of the Cardiovascular System

The Heart Roughly the size of a person’s closed fist Full size at about age 25 Tall, thin individuals tend to have a long heart and short, stocky individuals tend to have a wide heart.

Coverings of the Heart Covered by a sac called the pericardium Covered by a sac called the pericardium Fibrous Pericardium – tough, loose-fitting, and inelastic Fibrous Pericardium – tough, loose-fitting, and inelastic Serous Pericardium – has two layers Serous Pericardium – has two layers 1. Parietal layer – lines fibrous pericardium 2. Visceral layer (epicardium) – adheres to the outside of the heart.

Functions of the Heart Coverings Between the parietal and visceral layer is the pericardial space, which contains pericardial fluid Fluid protects against friction when the heart beats

Structure of the Heart Structure of the Heart 3 layers of tissue 3 layers of tissue Epicardium – same as the visceral pericardium Epicardium – same as the visceral pericardium Myocardium – Thick muscular layer Myocardium – Thick muscular layer Endocardium – lining of the interior myocardial wall. Endocardium – lining of the interior myocardial wall.

External Anatomy of the Heart Anterior View

External Anatomy of the Heart Posterior View

Chambers of the Heart Divided into 4 cavities Divided into 4 cavities 2 Atria (left and right) 2 Atria (left and right) Upper chambers Upper chambers Receive blood from veins Receive blood from veins Myocardial wall is thin Myocardial wall is thin 2 Ventricles (left and right) 2 Ventricles (left and right) Lower chambers Lower chambers Receive blood from the atria Receive blood from the atria Myocardial walls are thick for pumping Myocardial walls are thick for pumping

Chambers of the Heart (Frontal Plane)

Valves of the Heart Permit the flow of blood in one direction Permit the flow of blood in one direction Four sets of valves Four sets of valves 2 Atrioventricular (AV) Valves – guard the openings between the atria and ventricles (cusp valves) 2 Atrioventricular (AV) Valves – guard the openings between the atria and ventricles (cusp valves) Tricuspid valve Tricuspid valve Bicuspid valve (mitral valve) Bicuspid valve (mitral valve) 2 Semilunar (SL) Valves – located where the pulmonary artery and aorta arise from the right and left ventricles respectively 2 Semilunar (SL) Valves – located where the pulmonary artery and aorta arise from the right and left ventricles respectively

Chambers and Valves of the Heart

Mitral Valve Prolapse

Skeleton of the Heart

Structure of Heart Valves

Flow of Blood Through the Heart

Blood Supply of Heart Tissue Coronary Arteries – The right and left coronary arteries are the first branches off of the aorta. Coronary Arteries – The right and left coronary arteries are the first branches off of the aorta. Anastomosis – one or more braches from the proximal part of the artery to a more distal portion Anastomosis – one or more braches from the proximal part of the artery to a more distal portion Cardiac Veins – after blood passes through capillaries in the myocardium it enters a series of cardiac veins that drain into the right atrium

Coronary Arteries and Veins

Myocardial Infarction (MI)

Coronary Bypass Surgery