Ivalve idityaniswe ngamaqhoshana amabini, kwaye isakhiwo siqinile.Ngenxa yokuvala i-stroke emfutshane kunye nokulayishwa okuphuzi kwentwasahlobo, isantya sokuvala sikhawuleza, esinokunciphisa kakhulu i-hammer phenomenon yamanzi.I-valve ineempawu zomthamo omncinci, ubunzima obulula, isenzo esibucayi, ukutywinwa okuthembekileyo, ukufakela okufanelekileyo, njl njl. Inokufakwa ngokuthe tye okanye ngokuthe nkqo.