Assertion: valve's opening | /r/HasProperty | narrow
Facets:
Source sentences:
text: Diseased heart valves may have a narrow opening and therefore restrict the flow of blood in the forward direction (referred to as a stenotic valve), or may allow blood to leak in the reverse direction (referred to as valvular regurgitation).
text: When it is stenotic it represents a valvular opening that is narrowed, thus restricting blood flow through the valve.