Untitled

• Cardiovascular System - includes the heart, blood vessels, and blood.
• Heart Size - Approximately the size of a fist and weighs less than 1 lb.
• pericardium - double-layered sac anchoring and protecting the heart.
• Parietal pericardium - membrane around heart’s cavity/lines the fibrous pericardium.
• Visceral pericardium - membrane on heart’s surface/covers the heart surface.
• Pericardial cavity - space around heart/ located between the visceral and parietal pericardia, is filled with a thin layer of pericardial fluid produced by the serous pericardium.
• Coronary sulcus - extends around the heart, separating the atria from the ventricles.
• Two grooves, or sulci - extend inferiorly from the coronary sulcus and indicate the division between the right and left ventricles.
• Anterior interventricular sulcus - is on the anterior surface of the heart.
• Posterior interventricular sulcus- is on the posterior surface of the heart.
• Superior vena cava and inferior vena cava - carry blood from the body to the right atrium.
• Four pulmonary veins - carry blood from the lungs to the left atrium.
• Great vessels or great arteries - blood flows from the ventricles through large arteries.
• Pulmonary trunk - arising from the right ventricle, splits into the right and left pulmonary arteries, which carry blood to the lungs.
• Aorta - arising from the left ventricle, carries blood to the rest of the body.
• The heart is a muscular pump consisting of four chambers: (1)Right atrium,(2)Left atrium, (3)Right ventricle, and(4)Left ventricle.
• Atria - Superior chambers; Holding chambers; Small, thin walled; Contract minimally to push blood into ventricles.
• Interatrial septum - the two atria are separated from each other by a partition; separates right and left atria.
• Ventricles - Inferior chambers; Pumping chambers; Thick, strong walled; Contract forcefully to propel blood out of heart.
• Interventricular septum - the two ventricles are separated from each other; separates right and left ventricles.
• There are two types of heart valves: (1) atrioventricular valves and (2) semilunar valves.
• Atrioventricular valve - is located between each atrium and ventricle; Valves between the atria and ventricles.
• Tricuspid valve - AV valve between the right atrium and the right ventricle because it is composed of three cusps or flaps of tissue.
• Bicuspid valve (mitral valve) - AV valve between the left atrium and the left ventricle because it is composed of two cusps.
• Papillary muscles


  cone-shaped and muscular pillars, are found in each ventricle.
• Chordae tendineae - thin, strong connective tissue strings, attach the papillary muscles to the free margins of the cusps of the atrioventricular valves.
• Semilunar valve - have three half-moon shaped cusps, and are valves between each ventricle and its associated great artery/and are valves between the pulmonary trunk and aorta.
• Pulmonary semilunar valve - is located between the right ventricle and the pulmonary trunk.
• Aortic semilunar valve - is located between the left ventricle and aorta.
• Cardiac skeleton - sometimes referred to as a plate of connective tissue or fibrous skeleton, mainly consists of fibrous rings that surround the atrioventricular and semilunar valves, and give them solid support.
• Cardiac skeleton- acts as electrical insulation between the atria and ventricles while providing a rigid attachment site for cardiac muscle.
• Blood Flow through Heart

  1. Right Atrium 2. Tricuspid valve 3. Right Ventricle 4. Pulmonary semilunar valve 5. Pulmonary trunk 6. Pulmonary arteries 7. Lung tissues 8. Pulmonary veins 9. Left Atrium 10. Bicuspid valve 11. Left Ventricle 12. Aortic semilunar valve 13. Aorta 14. Body tissues
• Coronary arteries - supply blood to the wall of the heart; originate from the base of the aorta, just above the aortic semilunar valves.
• Left coronary artery - originates on the left side of the aorta and it has three major branches/supply blood to anterior heart wall and left ventricle.
• Right coronary artery - originates on right side of aorta; supply blood to right ventricle.
• Cardiac veins - drain blood from the cardiac muscle; pathways are nearly parallel to the coronary arteries, and most of them drain blood into the coronary sinus.
• Coronary sinus - a large vein located within the coronary sulcus on the posterior aspect of the heart.
• Heart wall is composed of three layers of tissue - (1) the epicardium, (2) the myocardium, and (3) the endocardium.
• Epicardium - also called the visceral pericardium, is a thin, serous membrane forming the smooth outer surface of the heart. It consists of simple squamous epithelium overlying a layer of loose connective tissue and adipose tissue.
• Myocardium - is the thick, middle layer of the heart, composed of cardiac muscle cells; responsible for contraction of the heart chambers.