Active_comparator: Elective Rotational Atherectomy

Operators can decide elective use of rotational atherectomy (RA) or conventional angioplasty according to the calcification patterns of the coronary lesion evaluated by Intravascular ultrasound (IVUS) or by angiography if the IVUS cannot cross the lesion.~Procedure is performed with a Rotablator system, consisting of a rotating olive-shaped burr whose leading hemisphere is coated with microscopic diamond chips. The proximal end of the device has a housing unit containing the burr advancer, a fiberoptic tachometer cable, an irrigation port, and a nitrogen gas delivery hose, which permits the rapidly rotating of the burr. The RA catheter is introduced into the coronary artery over a stainless steel 0.09-inch wire to cross the lesion, then advanced with a slow pecking motion at a speed of 160,000 to 190,000 rpm with each ablation run \<15 seconds is performed. Burr size was with a burr/vessel ratio of 0.7. After RA, all patients received IVUS-guided percutaneous coronary intervention.

Active_comparator: Bailout Rotational Atherectomy

The operators began with conventional angioplasty (non-compliant balloon dilatation) regardless of the calcification patterns in the coronary lesion, and rotational atherectomy (RA) can be used only as a bailout.