The relationship between coronary artery dimension after rotational atherectomy and burr size

Background: Rotational atherectomy has improved the treatment of heavily calcified coronary atherosclerotic lesions, but the relation ship between luminal dimension alter rotational atherectomy and rotablator burr size has yet to be elucidated. Methods and Results: After rotablation, 114 lesions were evaluated by IVUS as to luminal area (LA), major diameter (M), location, and arc of calcification. LA was 1.04 times larger than burr cross sectional area (1.04 ± 0.28, 0.38 ∼ 1.93), M was 1.13 times higher than burr size (1.13 ± 0.16, 0.70 ∼ 1.54). A subgroup analysis showed that M/B and LA/BA were significantly lower in in-stent lesions than in non-in-stent lesions (M/B: 1.03 ± 0.11 vs. 1.16 ± 0.16, LA/BA: 0.87 ± 0.15 vs. 1.10 ± 0.29 ; p < 0.005). Lesion eccentricity also affected the lumen size. In eccentric lesions, M/B=1.19 ± 0.18, LA/BA = 1.11 ± 0.32, whereas in concentric lesions, the M/B and LA/BA values were 1.07 ± 0.11, 0.97 ± 0.21 respectively (p < 0.05). Conclusions: Lumen obtained alter rotational atherectomy are often larger than expected, especially in eccentric or non-in-stent lesions, so we must determine burr size very carefully to minimize this effect.