Viking Olov Björk (3 December 1918, Sunnansjö,

Dalarna Dalarna () is a '' landskap'' (historical province) in central Sweden. English exonyms for it are Dalecarlia () and the Dales. Dalarna adjoins Härjedalen, Hälsingland, Gästrikland, Västmanland and Värmland Värmland () also known a ...

– 18 February 2009) was a

Swedish Swedish or ' may refer to: Anything from or related to Sweden, a country in Northern Europe. Or, specifically: * Swedish language, a North Germanic language spoken primarily in Sweden and Finland ** Swedish alphabet, the official alphabet used by ...

cardiac surgeon Cardiac surgery, or cardiovascular surgery, is surgery on the heart or great vessels performed by cardiac surgeons. It is often used to treat complications of ischemic heart disease (for example, with coronary artery bypass grafting); to cor ...

. In 1968, he collaborated with American engineer

Donald Shiley Donald Pearce Shiley (January 19, 1920 – July 31, 2010) was the inventor of the Bjork–Shiley valve, a prosthetic heart valve. He was a 1951 alumnus of the University of Portland, where he studied engineering. Early life He was born in Yak ...

to develop the Björk–Shiley valve, a mechanical prosthetic

heart valve A heart valve is a one-way valve that allows blood to flow in one direction through the chambers of the heart. Four valves are usually present in a mammalian heart and together they determine the pathway of blood flow through the heart. A heart v ...

. It was the first "tilting disc valve", used to replace the

aortic The aorta ( ) is the main and largest artery in the human body, originating from the left ventricle of the heart and extending down to the abdomen, where it splits into two smaller arteries (the common iliac arteries). The aorta distributes ox ...

mitral valve The mitral valve (), also known as the bicuspid valve or left atrioventricular valve, is one of the four heart valves. It has two cusps or flaps and lies between the left atrium and the left ventricle of the heart. The heart valves are all one-w ...

. Many modifications followed, including the convexo-concave valve. The convexo-concave valve had defects in form of strut fractures. Therefore, the monostrut valve was introduced to prevent outflow strut fractures. The Bjork–Shiley valve was manufactured by

Pfizer Pfizer Inc. ( ) is an American multinational pharmaceutical and biotechnology corporation headquartered on 42nd Street in Manhattan, New York City. The company was established in 1849 in New York by two German entrepreneurs, Charles Pfizer ...

after they bought the Shiley company in 1979. In 1980 Björk wrote to Pfizer threatening to publish cases of valve failures — often fatal to the patients — unless corrective action was taken. This eventually led to long lawsuit that involved the recall of all existing valves and Pfizer allocating up to US$20 million to pay compensation. Björk wrote his dissertation in 1948, titled "Brain perfusion in dogs with artificially oxygenated blood". Björk died on 18 February 2009 in Stockholm.

References

1918 births 2009 deaths People from Ludvika Municipality Swedish cardiac surgeons Academic staff of the Karolinska Institute People from Dalarna Academic staff of Uppsala University 20th-century surgeons {{Sweden-med-bio-stub