Safety of a high bolus dose of tirofiban in patients undergoing coronary stent placement

Abstract

To overcome the suboptimal platelet inhibition induced by tirofiban in the first hour after a percutaneous coronary intervention, a new regimen of 25 microg/kg bolus followed by an 18-hr infusion of 0.15 microg/kg/min has been proposed. The aim of this study was to compare the effects of this high bolus dose of tirofiban with those of abciximab on bleeding risk and 30-day clinical outcome in patients undergoing coronary stenting. We compared two cohorts of patients who underwent coronary stent placement between January 2000 and December 2002. In the first cohort, the only available IIb/IIIa receptor inhibitor was abciximab, which was given to 280 (34.9%) out of 802 stented patients; in the second cohort, tirofiban was administered to 274 (38.3%) out of 716 treated patients. The primary endpoints were the proportion of patients with major bleeding and the rate of site access complications; the 30-day incidence of major adverse cardiac events (MACE) was also assessed. After the procedure, the patients were given ticlopidine for 4 weeks and aspirin indefinitely. Major bleeding episodes were observed in four patients receiving abciximab and in none receiving tirofiban (1.4% vs. 0%; P = 0.12); the rates of site access complications were similar (3.6% vs. 3.3%; P = 0.96). The 30-day incidence of MACE was 7.1% in the abciximab group and 5.8% in the tirofiban group (P = 0.65). In patients undergoing coronary stenting, the high bolus dose of tirofiban is safe and not associated with an increased risk of major bleeding or site access complications in comparison with abciximab.

Angiographic and Clinical Outcome in ST-Segment Elevation Myocardial Infarction Patients Receiving an Adjunctive Double Bolus Regimen of Tirofiban for Primary Percutaneous Coronary Intervention

“…In many studies, tirofiban was injected immediately before PCI in the catheterization laboratory, with inconsistent results. 10,[12][13][14][15][18][19][20][21][22] Early administration of tirofiban improved angiographic outcome in subjects undergoing PCI for AMI in the TIGER-PA Pilot trial. 17 The potential importance of the timing of administration is also consistent with another study 21 in which, if tirofiban was administered after angiographic study but just before PCI, angiographic outcomes in patients receiving low and high doses were similar, even though there was a clear dose-related platelet aggregation inhibition.…”

“…11 Results from studies of the efficacy of adjunctive tirofiban in patients undergoing PCI have been inconsistent. [12][13][14][15][16][17][18][19][20][21][22][23] Some have shown beneficial angiographic and clinical outcomes, 20,22 whereas others show either no benefit 16 or modest initial clinical improvements, unsustained at 30-day follow-up. 13,17 Interpretation of these results is difficult because different dosing regimens were used; for example, tirofiban was administered at a conventional dose (10 g/kg bolus followed by 0.15 g·kg -1 ·min -1 for 18-36 h) in some studies [12][13][14][15]17,[21][22][23] and in others 16,[18][19][20][21] at a high dose (20-25 g/kg bolus followed 0.15 g·kg -1 ·min -1 for 18-24 h).…”

“…The conventional dose of tirofiban may not achieve adequate platelet aggregation inhibition compared with abciximab. 14,15,24 Timing of the administration of tirofiban before PCI also varied, [12][13][14][15][16][17][18][19][20][21][22][23] and patients with different clinical scenarios of acute coronary syndrome were studied. These factors are all likely to influence the results and so it remains unclear what the optimal regimen of adjunctive tirofiban therapy would be for PCI in various patient populations.…”

High‐dose tirofiban with enoxaparin and inflammatory markers in high‐risk percutaneous intervention

“…UFH heparin was administered as a bolus of 70 U kg )1 [23] prior to PCI and additional heparin was given to maintain the activated clotting time (ACT) at 250 s. Enoxaparin was administered at a dose of 0AE75 mg kg )1 [24]. Tirofiban was administered once the wire had crossed the lesion during PCI with a bolus dose of 25 lg kg )1 of bodyweight, followed by an infusion of 0AE15 lg per kilogram per min for 18-24 h [12,25].…”

“…Tirofiban is usually not indicated for administration during PCI as the results of the standard dose studied were considered unsatisfactory [10]. Limited published data are available on this high-dose regimen [10][11][12].…”