This blog is for medical students and for paramedics like nurses and medical technologists. Before watching the video, you should be familiar with medical terminologies used. A brief description of each is given here:
Atrium (Rt and Lt), plural is atria: These are two chambers at the upper part i.e. base of heart.
Ventricle (Rt and Lt), plural is ventricles: These are two chambers at the lower part of heart.
Vena cava, superior (upper) and inferior (lower), plural is venae cavae: These are large veins collecting blood from upper and lower parts of the body respectively and draining into right atrium.
Pulmonary (related to lungs) veins, drain blood from lungs to left atrium of heart.
Aorta: It is the largest artery of the body. Its main parts are ascending aorta, arch of aorta, descending aorta in thorax (chest) and abdominal aorta. Aorta supplies blood to all parts of body, except lungs, through its various branches.
Myocardium: Musculature or muscle of the heart.
Pericardium: Outer covering of the heart. It is outside myocardium and has two layers with a thin space in between containing slight fluid.
Heart valves: The openings of each atrium to its ventricle and each ventricle to its outlet, are guarded by the one-way valves to prevent regurgitation (back flow) of blood.
Mitral valve (right atrio-ventricular) valve, is between right atrium and right ventricle. It has two cusps (leaflets) and it allows blood from atrium to ventricle but not from ventricle to atrium.
Tricuspid valve (left atrio-ventricular) valve, is between left atrium and left ventricle. It has three cusps (therefore its name is tricuspid) and it allows blood from atrium to ventricle but not from ventricle to atrium.
Pulmonary valve, is located at the opening pulmonary artery in right ventricle. It has three cusps and it allows blood from right ventricle to pulmonary artery but not from artery to ventricle.
Aortic valve, is located at the opening of aorta in left ventricle. It has three cusps and it allows blood from left ventricle to aorta but not from aorta to ventricle.
Chordae tendineae, are strong fibrous cords connecting cusps of the atrio-ventricular valves to inner side of ventricles. These stop the cusps of the valves to open in reverse direction towards atria and hence prevent regurgitation of blood from ventricles to atria.
Trachea, is the main wind pipe, connecting larynx at the upper end to the lungs through its branches.
Oxygenated blood, is that blood which contains good oxygen.
De-oxygenated blood, is that blood which contains more carbon dioxide and much less oxygen.
Systemic circulation, oxygenated blood pumped by left side of the heart, going to all parts of the body and then de-oxygenated blood coming back from tissues to right side of heart.
Pulmonary circulation, de-oxygenated blood pumped by right side of the heart, going to lungs and then oxygenated blood coming back from lungs to left side of heart.
Cardio-phrenic angles, are corners seen on chest x-ray. These are between heart (cardio) and diaphragm (phrenic).
Costo-phrenic angles, are corners seen on chest x-ray. These are between rib cage (costo) and diaphragm (phrenic).
Cardio-thoracic ratio, is checked on x-ray chest. It is the size of heart as compared to the thoracic (chest) cavity. Normally it is less than 50%, increases in certain heart conditions and is known as cardiomegaly.