Intravascular ultrasound assessment of fibrous cap remnants after coronary plaque rupture

In general, the postrupture fibrous cap does not cover the entire mouth of the ruptured plaque cavity in its postrupture state. Potential explanations include the following: (1) part of the fibrous cap may be too thin to be visualized with IVUS, (2) part of it may have embolized, or (3) the prerupture fibrous cap may have been stretched and/or there were postrupture changes in lesion geometry.