Anticoagulant medication A substance that inhibits the blood clotting mechanism. Anticoagulant drugs are given to maintain the blood in a fluid state, thereby preventing abnormal or pathological clotting.
Anticoagulation See anticoagulant therapy or anticoagulant medication.
Anticoagulant therapy A management program of long-term anticoagulant drugs for patients with chronic propensities for blood clot formation.
Aorta The main artery that conducts oxygenated blood from the left ventricle of the heart and circulates it to the rest of the body.
Aortic valve A semilunar valve located between the left ventricle and the aorta that prevents backflow of blood into the left ventricle.
Arrhythmia An irregular heartbeat caused by a disturbance in the neural conduction system of the heart.
Arteries Blood vessels that carry blood away from the heart.
Atrium (atria) One of two chambers upper chambers of the heart that receives blood from the body or lungs.
Cryopreservation The preserving of living cells, tissues, or organs by subjecting them to very low temperature processes. Cells and tissues preserved by this method continue to maintain viability even after thawing and transplantation.
Coronary arteries The blood vessels that provide nourishment to the heart muscle. There are two coronary arteries, the right and the left, and they originate behind two of the three leaflets of the aortic valve.
Coumarins A family of anticoagulant drugs that inhibit the formation of certain blood clotting factors made by the liver.
Coumadin® Brand name of the most widely used anticoagulant.
Effective orifice area (EOA) The area of the valve that allows forward flow of blood.
Embolism A particle, such as a thrombus, debris or an air bubble, circulating in the bloodstream.
Gradient The pressure difference from one side of the valve to the other measured in millimeters of mercury.
Heart failure Inability of the heart to effectively and efficiently move the blood throughout the body. The most common causes are blocked coronary arteries, diseased native heart valves and deformities at birth but there are many other causes.
Heart valve An anatomical structure in the heart that regulates blood movement.
Hemodynamics The study of the movements of blood.
Hemolysis Red blood cell damage, which can lead to hemolytic anemia.
Homograft valve The aortic valve and short section of the aorta immediately above the valve taken from a human donor.
Incompetence With heart valves, the inability to close completely and prevent backflow. Also known as insufficiency or regurgitation.
Inferior vena cava The large vein that collects deoxygenated blood from the veins of the legs and lower body and delivers it to the right atrium.
International Normalized Ratio (INR) is a measurement of the level of anticoagulant medication activity in the blood determined by blood test. It is an indexed ratio of patient Protime to the Protime normal range. Protime is the number of seconds it takes the blood to start clotting in the presence of certain factors. An INR of 1.0 (one) is normal for people not taking anticoagulant medication. For patients with mechanical heart valves, an INR of 2-3.5 is recommended.15
Insufficiency (or regurgitation) A heart valve disease that allows backward flow of blood through a closed valve.
Left atrium The left upper chamber of the heart, which receives oxygenated blood from the lungs via the four pulmonary veins.
Left ventricle The left lower chamber of the heart, which receives oxygenated blood from the left atrium and pumps it to the systemic circulation via the aorta.
Mechanical prosthetic valve A prosthetic device implanted to replace diseased heart valves. Current devices are made from various materials including pyrolytic carbon, graphite carbon, tungsten, titanium, and synthetic fabric.
Mitral valve A large parachute type atrio-ventricular valve located between the left atrium and the left ventricle that prevents backflow of blood into the left atrium.
Pericardium A tissue sac that surrounds the heart.
Pericardial effusion Excess fluid accumulation in the cavity that surrounds the heart in the chest.
Pericarditis Inflammation of the tissue that surrounds the heart cavity in the chest.
Pivot (valve pivot) A pivot is a recessed or protruding area in the orifice of a mechanical heart valve where the leaflets of the valve are secured. Pivot geometry dictates valve leaflet opening and closing angles.
Pleural effusion Excess fluid accumulation in the lungs.
Pleuritis Inflammation of the membrane that surrounds the lungs in the chest.
Pneumonia Inflammation of the lungs caused by bacteria, viruses, chemical irritants, allergies. Symptoms are fever, chills, pain in the chest, cough, production of sputum that appears infected or bloody.
Porcine valve A biological valve derived from a pig (a variety of heterograft or xenograft).
Pressure gradient The difference in pressure between two areas, which for a heart valve signifies the pressure difference across the valve. Gradient is a reflection of the efficiency of the heart valve—the lower the gradient, the better the valve.
Prosthesis An artificial body part.
Prosthetic heart valve A prosthesis that is implanted to replace a natural heart valve or failed prosthesis. Prosthetic valves can be mechanical or tissue (biological).
Pulmonary Pertaining to the lungs.
Pulmonary artery The large artery that conducts deoxygenated blood from the right ventricle to the lungs.
Pulmonary circulation The circulation of deoxygenated blood through the lungs, where the blood becomes oxygenated. It is also known as the lesser circulation because the flow path is short and lower pressure is required for it to operate efficiently.
Pulmonary valve A semilunar valve located between the right ventricle and the pulmonary artery that prevents backflow of blood into the right ventricle.
Pulmonary vein A large blood vessel that returns blood to the heart from the lungs.
Pyrolytic carbon Carbon from a carbon gas that is deposited on the surface of valve parts after the gas is split at very high temperature. Pyrolytic carbon has a smooth porcelin-like surface when polished. Some pyrolytic carbon contains silicon.
Regurgitation (valve regurgitation) A heart valve disease that allows backward flow of blood through a closed valve OR blood that flows backward during the closed phase of a mechanical or tissue heart valve.
Right atrium The right upper chamber of the heart, which receives deoxygenated blood from the systemic venous system.
Right ventricle The right lower chamber of the heart, which receives deoxygenated blood from the right atrium and pumps it to the lungs via the pulmonary artery.
Ross procedure An autograft procedure performed using the patient’s own pulmonary valve and root to replace a diseased aortic valve and root. The pulmonary root is replaced with a homograft or stentless valve.
Sewing cuff A synthetic cloth structure attached to the outer circumference of a manufactured heart valve to allow attachment of the valve inside the heart.
Silicon carbide A compound composed of silicon and carbon found in older manufactured valve models. Silicon carbide is more thrombogenic than pure carbon.70
Stenosis A narrowing of the heart valve orifice (opening), which prevents the valve from opening completely and decreases the blood flow through the valve.
- Aortic Stenosis: a narrowing of the aortic valve orifice.
- Mitral Stenosis: a narrowing of the mitral valve orifice.
Stented tissue valve Cow or pig tissue that is mounted on a plastic frame with a sewing cuff of synthetic material to function similarly to the native heart valve.
Stentless tissue valve The aortic valve and the aorta immediately above it from a pig including the coronary artery ostia (opening) and segments that is usually reinforced with synthetic material externally for attachment to a patient’s aortic root area.
Sternum The narrow, flat bone in the middle of the front chest. It is familiarly called the breastbone.
Structural failure Failure of prosthetic valve parts to function correctly.
Superior vena cava The large vein that collects deoxygenated blood from the veins of the head and upper body and delivers it to the right atrium.
Systemic circulation The circulation of oxygenated blood from the left ventricle of the heart to all systems and organs of the body. It is also known as the greater circulation because the flow path is long and higher pressures are required for it to operate efficiently.
Thrombosis The formation of a blood clot in a blood vessel, a chamber of the heart, or a natural or prosthetic heart valve.
Thrombus A stationary blood clot.
Tissue valve (prosthetic tissue valve) A general term that can be used to refer to a non-living glutaraldehyde-preserved valve and/or aortic root or to a living cryopreserved graft. Tissue valves can be stented, stentless, or homograft aortic roots.
May be further subdivided into:
- Allograft: Donor and recipient of the graft are the same species (i.e., human)
- Homograft: Donor and recipient of the graft are the same species (i.e., human)
- Heterograft: Donor and recipient of the graft are different species (e.g., pig)
- Xenograft: Donor and recipient of the graft are different species (e.g., pig)
- Autograft: Transplant from one part to another part of a patient’s own body
Tricuspid valve An atrio-ventricular valve located between the right atrium and the right ventricle that prevents backflow of blood into the right atrium.
Vitamin K A dietary nutrient found in green vegatables that counteract the effects of warfarin sodium (Coumadin®).