<prompt> Answer this question truthfullyWhat does the term irregular lesion mean in the context of coronary angiography?  <response>: <reason> Coronary artery lesion irregularity is assessed visually using a well defined grading system:Grade 0: Smooth no irregularity.Grade 1: Mildly Irregular lesion has an indistinct lumen edge.Grade 2: SawtoothedGrossly Irregular lesion has defined jagged or sawtoothed lumen edges.NOTE: The presence of an ulcer, dissection, or thrombus will also make a lesion irregular. 