Assertion: mechanical valve | /r/HasProperty | durable
Facets:
value: very
type: DEGREE
Source sentences:
text: A mechanical valve made of metal, which requires you to take *blood thinners but is very durable; A valve made from biological tissue, which requires no blood thinners but may not last as long and may need to be replaced later; A homograft or valve from a donated human heart and preserved in special solutions may be use.