Dr. Mustard, with support from the Heart and Stroke Foundation of Canada, developed the first operation to correct a congenital heart defect that produced “blue babies”. The defect is called transposition of the great vessels. The condition was common and fatal. The defect causes blood from the lungs to flow back to the lungs and blood from the body to flow back to the body. This occurs because the aorta and the pulmonary artery, the two major arteries coming out of the heart, are connected to the wrong chambers. The babies look blue because there is insufficient oxygen circulating in their bodies.
The Mustard Procedure allows total correction of transposition of the great vessels. The procedure employs a baffle to redirect caval blood flow to the left atrium which then pumps blood to the left ventricle which then pumps the deoxygenated blood to the lungs. In a normal heart, de-oxygenated blood is pumped into the lungs via the right ventricle. Then it is distributed throughout the body via the left ventricle. In the Mustard procedure, blood is pumped to the lungs via the left ventricle and disseminated throughout the body via the right ventricle.
The Mustard procedure improved an 80% mortality rate in the first year of life to an 80% survival at age 20.
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The Mustard procedure was largely replaced in the late 1980s by the Jatene procedure (arterial switch), in which the native arteries were switched back to normal flow, so that the RV (right ventricle) would be connected to the pulmonary artery and the LV (left ventricle) would be connected to the aorta. This surgery had not been possible prior to 1985 because of difficulty with re-implanting coronary arteries which perfuse the actual heart muscle itself (myocardium).
- Press Release – Children who had heart surgery 20-30 years ago should keep in touch, June 6, 2001, Heart and Stroke Foundation of Canada. URL: http://ww2.heartandstroke.ca/Page.asp?PageID=33&ArticleID=1056. Accessed on: January 14, 2008.