1 Swap in a new set of shoes, reconnect the brackets & springs, put the drum back on and youâre done.  Thereâs no need for compressors, or opening fluid lines to retract pistons with these setups. As a matter of fact, replacing brake shoes on some vehicles can be accomplished in under 2 minutes, once the drum is removed.
The bicuspid valve, sometimes better known as the mitral valve, allows blood to flow in only one direction (assuming it is functional) from the left atrium to the left ventricle, it prevents blood from flowing back from the left ventricle into the left atrium.
The flaps of the mitral and tricuspid valves open to let blood through. Then, the ventricles contract to pump the blood out of the heart. When the ventricles contract, the flaps of the mitral and tricuspid valves close. They form a tight seal that prevents blood from flowing back into the atria.For more information, go to the Health Topics How the Heart Works article.n MVP, when the left ventricle contracts, one or both flaps of the mitral valve flop or bulge back (prolapse) into the left atrium. This can prevent the valve from forming a tight seal. As a result, blood may leak from the ventricle back into the atrium.