motion artifact in left main and proximal left anterior descending arteries

CT multiplanar reconstructions show motion artifact in left main and proximal left anterior descending arteries during best middiastolic phase (70% of the R-R interval, left) for this patient. Cleaner reconstruction correctly excludes significant stenosis during early diastolic phase (40% of the R-R interval, right). Arrows = proximal left anterior descending artery, AO = aorta, LA = left atrium, RVOT = right ventricular outflow tract.