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Slide Show: 7 Artificial Valves That Lend Hearts a Helping Hand

For the past five decades, artificial heart-valve designs have evolved to successfully replace natural valves, which often begin to leak or harden over time

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VALVE REPAIR

Sometimes a whole new valve is unnecessary, and a surgeon can use a ring like this to restructure the faulty valve. "Repair is definitely a lot better," Yoganathan says. "You still maintain a lot of the natural function." According to the Mayo Clinic, the original valve better resists infection, does not require blood thinners and generally means a longer life expectancy.....[ More ]

COLLAPSIBLE VALVE

Open-heart surgery is not an option for many patients of fragile health, so researchers designed this collapsible valve—available since 2007 in Europe, but not yet approved in the U.S.—that can be slipped into an artery without cutting open the chest.....[ More ]

COW-BASED VALVES

Today, many valves are made from cows, with tissue mounted in a wire frame covered with Dacron fabric, a design around since the 1980s. Cutting leaflets out of the sac that surrounds a cow's heart, valve-makers can make any required shape or size; they can also use chemicals to make the tissue less likely to attract the calcium that can harden a valve.....[ More ]

PIG VALVES

To avoid the risk of blood clots, Parisian doctor Alain Carpentier developed pig valves, first implanted in 1965. Valve-makers use the chemical glutaraldehyde, a common tissue stabilizer used in laboratories and embalming, to sterilize and inactivate the tissue so the patient's immune system won't attack it.....[ More ]

SALOON DOORS

The most common mechanical valve in use today is this double-door design, first implanted in the 1970s, made of carbon-based material with two flaps that open and close with the pumping of blood. Mechanical valves are durable and long-lasting, but because they can cause dangerous blood clots to form, patients must take blood thinners such as warfarin for the rest of their lives.....[ More ]

TILTING DISC

The marble-in-a-cage valve took up a lot of space, pressing on other body parts, so valve-makers sought a flatter design. Tilting discs like this design, invented in 1977 and still in use today, rely on a disc that flips open "like a toilet seat," Yoganathan says.....[ More ]

MARBLE-IN-A-CAGE

The first successful artificial heart valve was this marble-in-a-cage model developed by Miles "Lowell" Edwards and cardiothoracic surgeon Albert Starr and first used in 1960. When resting against the ring, the caged ball prevents backward blood flow into the heart.....[ More ]

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