Journal of Invasive Cardiology

Patients and study protocol. This is a single-center, open-label, randomized study of patients selected from the percutaneous transluminal coronary angioplasty population of the Interventional Unit at the University Hospital of Catania. Patients with demonstrable reversible ischemia and severe (> 70%) de novo native coronary stenoses requiring implantation of either a stent longer than 20 mm or of multiple overlapping stents were included. Patients were excluded if they had a saphenous graft lesion, bleeding diathesis, thrombocytopenia (< 100,000 cells/ml), history of stroke in the previous two years, active internal bleeding, severe uncontrolled hypertension (systolic blood pressure > 180 mmHg, diastolic blood pressure > 100 mmHg), major surgery or trauma within 6 weeks.
Between October 1996 and February 1998, a total of 512 percutaneous coronary interventions were performed. An intracoronary stent implantation was performed in 368 patients (72%). One-hundred and seven patients (29%) treated with elective implantation of either a stent longer than 20 mm or of multiple overlapping stents form the intent-to-treat population of the study. The randomization to study medication was performed with a standard list of random numbers. All patients had a complete blood cell count and cardiac enzyme checks at 6, 12, 24, 36 and 48 hours post-procedure and at discharge. They were regularly followed at 1, 3 and 6 months to obtain clinical information after the procedure and to perform repeat angiography in case of recurrent angina. All patients underwent 6-month angiographic follow-up. The protocol was approved by the ethical committee of our hospital.
Study medication and adjunctive therapy. All patients received 325 mg aspirin orally the day before the procedure, and daily thereafter. Ticlopidine 250 mg twice daily was started the day before the intervention and was prescribed to all patients for four weeks following the procedure. Patients were randomly assigned to one of the two study medication treatment groups: 1) placebo with standard dose, weight-adjusted heparin [100 U/kg bolus to a maximum of 100,000 units with supplemental heparin to target a procedural activated clotting time (ACT) of < 300 seconds (heparin group)]; or 2) abciximab with low-dose, weight-adjusted heparin [70 U/kg bolus to a maximum of 70,000 units with supplemental heparin to target a procedural ACT of < 200 seconds (abciximab group)]. For those receiving abciximab, a bolus of 0.25 mg per kilogram of body weight was administered 10–60 minutes before intervention, followed by an infusion of 0.125 µg per kilogram per minute (maximum, 10 µg per minute) for 12 hours. No heparin administration was given after the completion of the procedure in either group and vascular access sheaths were removed following the procedure when the activated clotting time was < 150 seconds. All patients provided written informed consent for the study.

Randomization. Randomization was performed with the use of closed envelopes. A research nurse was asked to open the envelop every time a case was enrolled. Interventionalists were not blinded to the randomization, but they had no control over the group assignment even when more than one case per day was randomized.