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Titanium Heart Valve TV Commercial ~ 1969 United States Steel
🕑 Added 2020-02-23 19:25:10 +0000 UTCmore at http://quickfound.net/
Commercial for United States Steel for their titanium heart valves... beating titanium heart valve, looks tike steel ball bouncing in a basket...'
Originally a public domain film from the Library of Congress Prelinger Archives, slightly cropped to remove uneven edges, with the aspect ratio corrected, and one-pass brightness-contrast-color correction & mild video noise reduction applied.
The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and/or equalization (the resulting sound, though not perfect, is far less noisy than the original).
https://en.wikipedia.org/wiki/Artificial_heart_valve
Wikipedia license: http://creativecommons.org/licenses/by-sa/3.0/
An artificial heart valve is a device implanted into the heart of a patient to replace a dysfunctional native heart valve (valvular heart disease).
The human heart contains four valves: tricuspid valve, pulmonic valve, mitral valve and aortic valve. Their main purpose is to keep blood flowing in one direction through the heart, and from the heart into the major blood vessels connected to it (the pulmonary artery and the aorta). Heart valves can malfunction for a variety of reasons, which can impede the flow of blood through the valve (stenosis) and/or let blood flow backwards through the valve (regurgitation). Both processes put strain on the heart and may lead to serious problems, including heart failure.
Although some dysfunctional valves can be treated with drugs or repaired , others need to be replaced with an artificial valve...
The three main types of artificial heart valves are mechanical, biological (bioprosthetic/tissue), and tissue-engineered valves. In the US, UK and the European Union, the most common type of artificial heart valve is the bioprosthetic valve. Mechanical valves are more commonly used in Asia and Latin America.[citation needed] Companies that manufacture heart valves include Edwards Lifesciences, Medtronic, Abbott (St. Jude Medical), LivaNova, CryoLife, and LifeNet Health.
Mechanical Valves
Types of mechanical valves
Mechanical valves come in three main types – caged ball, tilting-disc and bileaflet – with various modifications on these designs. Caged ball valves are no longer implanted, but many patients are still living with this type of valve. Bileaflet valves are the most common type of mechanical valve implanted in patients today...
The first artificial heart valve was the caged ball valve, in which a ball is housed inside a cage. When the heart contracts and the blood pressure in the chamber of the heart exceeds the pressure on the outside of the chamber, the ball is pushed against the cage and allows blood to flow. When the heart finishes contracting, the pressure inside the chamber drops and the ball moves back against the base of the valve forming a seal.
In 1952, Charles A. Hufnagel implanted caged ball heart valves into ten patients (six of whom survived the operation), marking the first long-term success in prosthetic heart valves. A similar valve was invented by Miles 'Lowell' Edwards and Albert Starr in 1960 (commonly referred to as the Starr-Edwards silastic ball valve). This consisted of a silicone ball enclosed in a methyl metacrylate cage welded to a ring. The Starr-Edwards valve was first implanted in a human on August 25, 1960, but was discontinued by Edwards Lifesciences in 2007.
Caged ball valves are strongly associated with blood clot formation, so patients who have one required a high degree of anticoagulation, usually with a target INR of 3.0–4.5...
Introduced in 1969, the first clinically available tilting-disc valve was the Bjork-Shiley valve. Tilting‑disc valves are made of a metal ring covered by an ePTFE fabric. The metal ring holds, by means of two metal supports, a disc that opens when the heart beats to let blood flow through, then closes again to prevent blood flowing backwards. The disc is usually made of an extremely hard carbon material (pyrolytic carbon), enabling the valve to function for years without wearing out...
Introduced in 1979, bileaflet valves are made of two semicircular leaflets that revolve around struts attached to the valve housing. With a larger opening than caged ball or tilting-disc valves, they carry a lower risk of blood clots. They are, however, vulnerable to blood backflow...
