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Excerpt from "Mitral Valve Repair" module

"The mitral valve is located between the heart's left atrium and left ventricle. The valve itself consists of two flaps (or leaflets) surrounded by a fibrous ring (the annulus). Muscles and tendons lie underneath the valve. All of the components must work together to ensure the valve functions normally.

Oxygen-rich blood flows from the lungs into the left atrium. It then passes through the open mitral valve into the left ventricle, which is the heart's main pumping chamber. When the left ventricle contracts, the mitral valve closes. This forces the blood to flow from the left ventricle to the aorta, and out to the body.

If the valve does not close properly, blood can leak backwards into the left atrium and lungs. This is called mitral valve regurgitation. Mitral valve regurgitation results from the abnormal function of any of the components of the valve, such as; degenerative mitral valve disease, infection, congenital defects, or muscle weakness due to previous heart attacks.

A less common valve disorder is mitral valve stenosis. This is when the mitral valve narrows and does not open properly. The tight valve prevents blood from flowing into the left ventricle. Mitral valve stenosis is found in individuals who have had rheumatic heart disease.

Left untreated, mitral valve disorders can cause shortness of breath, weakening of the heart muscle, congestive heart failure, and death."

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Excerpt from "Lung Volume Reduction Surgery" module

"Emphysema is a progressive lung disease most often associated with cigarette smoking. The disease permanently damages the air sacs (alveoli) in the lungs. This traps air in the lungs, and also causes the lungs to become weak and distended, like an overused rubber band.

Sometimes the disease is distributed evenly throughout the entire lung, and sometimes it is confined to one area of the lung. The pressure from the distended areas of the lung compresses the nearby healthy lung tissue. This makes it difficult to exchange oxygen and carbon dioxide when exhaling.

Lung volume reduction surgery (LVRS) is one of only a few surgical treatments for patients with severe emphysema. It involves eliminating up to 30 percent of the lung’s total volume. This reduces the pressure caused by the distended areas of the lung, allowing the healthy parts of the lung to function better.

Surgeons at the University of Wisconsin have performed between 50 and 100 LVRS procedures over the past 10 years, with good to excellent results in 80 to 85 percent of patients.

While LVRS does not cure emphysema, it can, for a very specific group of emphysema patients, improve quality of life and provide an alternative to lung transplantation."

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