The case for a qualitative lesion assessment system for coronary angiography.

Since the advent of coronary angiography, the standard for reporting of coronary lesion severity has been to utilize percent diameter stenosis (%DS). Given the imperfections of %DS as well as the widespread availability of intraprocedural intracoronary imaging and physiology assessment, it is time to consider a simpler yet more clinically relevant lesion assessment system. We compiled ten actual cases and presented these cases to 10 operators, providing 100 independent lesion assessments. For each case, operators were asked to describe lesions using %DS and a simplified lesion assessment system. We assessed the relationship between %DS and qualitative lesion assessment as well as the relationship of both measurements to the chosen plan. Greater variability exists with %DS than with qualitative lesion assessment. Despite this, there is good correlation between %DS and the qualitative lesion assessment (ρ = 0.8221). There remains overlap of lesion assessment using the qualitative lesion assessment tool suggesting that even with this simpler tool, there remains interobserver variability (ICC = 0.5164, 95% confidence interval [CI] 0.2924-0.7955). When assessing how both lesion assessment, there appears to be a stronger correlation between the qualitative lesion assessment and the chosen plan versus the %DS and the chosen plan (ρ = 0.9069 vs ρ = 0.8001, P < .01). Given the superior performance of the proposed qualitative system and the ability to estimate lesion severity using both anatomic and clinical factors, we feel that professional societies and clinicians should begin to embrace this simplified means of lesion assessment.