Which of the following is a key feature of non-compliant balloons?

• A. Distributes even radial force along the length
• B. Rigidly conform to vessel shape
• C. Always easy to track through tortuous vessels
• D. Always inflate to larger diameters than nominal

Answer: (A)

Non-compliant balloons are high‑pressure balloons that change diameter very little as you increase the inflation pressure, allowing a precise, predetermined lumen size to be achieved. Because their diameter remains essentially fixed once inflated, the force they exert is distributed more evenly along the entire length of the balloon, leading to uniform dilation of the targeted segment and reducing the risk of focal overexpansion at a single point. This makes them particularly useful for treating resistant or calcified lesions where you want controlled, predictable enlargement without creating irregularities.

The other statements don’t fit as well. They don’t rigidly conform to every vessel shape—their stiffness helps prevent overexpansion, but they don’t necessarily “hug” irregular contours the way a highly conformable balloon might. Tracking through tortuous vessels can actually be more challenging with a stiffer non‑compliant balloon. And they are designed to maintain a specific diameter rather than routinely inflating to larger diameters than nominal.