Which type of stent expands on its own when deployed in the vessel?

• A. Balloon Expandable
• B. Self Expandable
• C. Drug Eluting
• D. Resorbable

Answer: (B)

Self-expandable stents expand automatically when released from the delivery system because they are made of a shape‑memory alloy (usually nitinol) that springs to its preset diameter once the constraining sheath is withdrawn. This material-property-driven expansion allows the stent to conform to the vessel wall without needing balloon inflation. Balloon-expandable stents, by contrast, require a balloon to be inflated to push the stent open. Drug-eluting describes a coating that releases medication to reduce restenosis and does not determine how the stent expands. Resorbable stents are designed to gradually dissolve over time and are typically deployed with balloon expansion rather than self-expansion. Therefore, the type that expands on its own is the self-expandable stent.