Modifiable and unmodifiable factors associated with slow flow following rotational atherectomy.

Slow flow was positively associated with several unmodifiable factors including lesion length and angulation, and inversely associated with reference diameter. In addition, slow flow was positively associated with several modifiable factors including initial burr-to-artery ratio and use of beta blockers, and inversely associated with primary RA strategy, short single run, and systolic blood pressure just before RA. Application of this information could help to improve RA procedures.