Heparin or EX 527 in vivo bivalirudin was given to maintain an ACT > 250 seconds or an ACT of > 200 seconds with concomitant use of glycoprotein IIb/IIIa (GpIIb/IIIa) as per protocol. The OAS procedure was initiated by crossing the coronary lesion with the ViperWire Advance® coronary guide wire (Cardiovascular Systems, Inc., St. Paul, MN). Predilation with balloon angioplasty could be performed at the investigators’ discretion to allow introduction

of the IVUS imaging catheter for pre-procedural scan completion. The OAS procedure was initiated with the smallest crown size (choice of 1.25, 1.5, 1.75 or 2.0 mm) that was necessary to modify the calcified plaque and facilitate the delivery of the stent. OAS rotational crown speed ranged from 80,000 to 120,000 rotations per minute (rpm). After OAS treatment, dilatation with balloon angioplasty before and after stenting was allowed. Post-procedure residual stenosis was reported as a percentage of the vessel diameter, which was measured angiographically and evaluated by the treating physician. Device success was defined as a final achievement of ≤ 50% residual stenosis of the target lesion after OAS use only (before stent placement or any other adjunctive treatment), without a device malfunction. Procedural success was defined as ≤ 20% residual stenosis after stent placement. Debulking was based on pre- and post-diameter

stenosis of lesions treated

with OAS. Post-stent placement, antiplatelet therapy was given at the discretion of the investigator find more and consisted of ≥ 75 mg of aspirin given indefinitely and clopidogrel 75 mg daily given according to the stent manufacturer’s recommendation (typically, for 1 year if a DES stent was implanted). Patients were followed at 30 days, 3 months, 6 months, 2 years and 3 years post-index PDK4 treatment. The safety of the OAS was evaluated by procedural success, device success, TLR and overall major adverse cardiovascular events (MACE) rates at 6 months, 2 years and 3 years. The MACE rate was defined as a composite endpoint of cardiac death, MI and need for TLR. Per the study protocol, a Q-wave MI was defined as the development of a new pathological Q-wave greater than 1 mV in two or more contiguous leads while a non-Q-wave MI was defined as post-procedure elevation of CK to 3 times the upper lab normal value with elevated CK-MB and without pathological Q-waves present on the electrocardiogram. TLR was defined as any repeat revascularization of the target lesion. Reporting of angiographic complications consisted of no flow or slow flow due to distal embolization, abrupt or threatened closure of the treated vessel, spasm requiring any surgical intervention (which could not be resolved via medications), dissection, perforation and other events seen angiographically.