What is a potential consequence of using an oversized catheter or sheath relative to the artery?

• A. Using a catheter or sheath that is oversized increases vascular trauma and complication risk.
• B. Using an oversized device reduces procedure time.
• C. Size does not affect complication risk.
• D. Undersized devices cause no issues either.

Answer: (A)

Oversizing a catheter or sheath for the artery directly increases vascular trauma and the likelihood of complications. When the device fits the artery too tightly, it drags against the inner lining of the vessel, producing friction and shear stress that can tear the intima, cause dissections or even perforation, and promote clot formation. This also makes hemostasis harder after the device is removed and raises the risk of access-site hematomas, pseudoaneurysms, or arteriovenous fistulas. In short, a device that is too large for the vessel disrupts the delicate vessel wall and heightens complication risk. Using an appropriately sized device helps minimize these dangers, and attempting to speed the procedure with an oversized device is not advantageous.