Pericardium
A thin sac composed of fibrous material that surrounds the heart.
Visceral Layer of the Pericardium
The inner layer, which lines the surface of the heart.
Blood Flow of the Heart
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What is S1 and S2?
Lub - Dub" Normal complete heart beat
Heart Murmur
Harsh blowing sounds caused by disruption of blood flow into the heart
Stenosis
Narrowing of the left mitral valve.
Regurgitation
Back-flow in the heart
Systole
Refers to the phase of ventriclular contraction. Ventricles have been filled, then contract to expel blood iinto the aorta and pulmonary arteries
Friction Rub
Refers to a rough, grating sound caused by the rubbing together of organs
Mitral Stinosis
Narrowing of the left mitral valve
Coronary Muscle
Transport blood with nutrients and oxygen to myocardial muscle. Located above the aortic valve. Plaque in these arteries can cause death
Coronary Veins
The vessels that remove deoxygenated blood from the heart muscle
SA Node
Initiates the electrical impulse. Referred to as the "Pacemaker" of the heart. Has a firing rate of 60 - 100 beats/minute
What is the PR Interval?
Atrial Depolarization
What is the QRS Complex?
Ventricular Depolarization
What is the ST Interval?
Ventricular Repolarization
Parietal
Outer layer that lines the inside of the fibrous pericardium
Visceral
Inner layer: lines the surface of the heart.
Epicardium
Outer layer made up of squamous cells
Myocardium
Thin muscular layer. Forms most of the heart wall. It has striated muscle fibers that cause the heart to contract
Endocardium
Hearts inner layer. Consists of endothelial tissue with small blood vessels and bundles of smooth muscle
Heart Valves (Right to Left)
Bicuspid
Mitral
Aortic
Pulmonic
Diastole
Refers to the phase of ventricular relaxation. The ventricles relax and are filled as the atria contract.
Intra-Atrial Conducting Pathways
These fibers assist in the flow of the electrical current
AV Node
Receives the current that has finished spreading throughout the atria. The AV node is also capable of initiating electrical impulses in the event of SA node failure. Firing rate of 40 - 60 beats/minute
Bundle of His
Receives the current that has finished spreading through the atria
Right & Left Bundle Branches
Spreads the electrical current through the ventricle myocardial tissue
Purkinje Fibers
The fibers fan out and penetrate into the myocardial tissue to spread the current into the tissue. Firing rate of 20 - 40 beats per minute
Cardiac Nerves
Stimulates the heart
Pulmonary Circulation
Carries deoxygenated blood to the lungs where carbon dioxide is exchanged for oxygen.
After going through the pulmonary network, oxygenated blood returns to the left atrium via the pulmonary veins
Systemic Circulation
Supplies freshly oxygenated blood to the body's periphery and returns deoxygenated blood to the pulmonary circuit
Stroke volume
Amount of blood that is ejected with each heartbeat. Normal stroke volume is 55 to 100 ml/beat
Cardiac output
Amount of blood ejected from the left ventricle over one minute. Normal adult output is 4 to 8 liters/minute
Cardiac index
Diagnostic measurement of the effectiveness of the pumping action of the heart
Ductus Arteriosus
btw pulmonary artery & descending aorta - closes 24-46 hrs after birth
Foramen Ova
btw right & left atria - closes shortly after birth
Myocardial Ischemia
the oxygen needs of the heart are not met as it works harder, and an ischemic process ensues
Heart Failure
inability of the heart to produce a sufficient pumping effort. Left sided causes blood to back up into the pulmonary system and results in pulmonary edema. Right sided heart failure causes back up of the blood into the systemic circulation and leads to di
Myocardial Infarction
disruption of oxygen and nutrient flow to the myocardial tissue
Ventricular Hyertrophy
occurs in response to pumping against high pressures
Mitral Stenosis
narrowing of the left mitral valve
Aortic Stenosis
narrowing of the aortic valve
Mitral Regurgitation
backflow of blood from the left ventricle into the left atrium
Pulmonic Stenosis
narrowing of the opening btw the pulmonary artery and the right ventricle
Tricuspid Stenosis
narrowing or stricture of the tricuspid valve of the heart
Mitral Valve Prolapse
prolapse of the valve leaflets
Aortic Regurgitation
backflow of blood from the aorta into the left ventricle