Bivalirudin versus Heparin Monotherapy in Myocardial Infarction.

BACKGROUND: The comparative efficacy of various anticoagulation strategies has not been clearly established in patients with acute myocardial infarction who are undergoing percutaneous coronary intervention (PCI) according to current practice, which includes the use of radial-artery access for PCI and administration of potent P2Y12 inhibitors without the planned use of glycoprotein IIb/IIIa inhibitors. METHODS: In this multicenter, randomized, registry-based, open-label clinical trial, we enrolled patients with either ST-segment elevation myocardial infarction (STEMI) or non-STEMI (NSTEMI) who were undergoing PCI and receiving treatment with a potent P2Y12 inhibitor (ticagrelor, prasugrel, or cangrelor) without the planned use of glycoprotein IIb/IIIa inhibitors. The patients were randomly assigned to receive bivalirudin or heparin during PCI, which was performed predominantly with the use of radial-artery access. The primary end point was a composite of death from any cause, myocardial infarction, or major bleeding during 180 days of follow-up. RESULTS: A total of 6006 patients (3005 with STEMI and 3001 with NSTEMI) were enrolled in the trial. At 180 days, a primary end-point event had occurred in 12.3% of the patients (369 of 3004) in the bivalirudin group and in 12.8% (383 of 3002) in the heparin group (hazard ratio, 0.96; 95% confidence interval [CI], 0.83 to 1.10; P=0.54). The results were consistent between patients with STEMI and those with NSTEMI and across other major subgroups. Myocardial infarction occurred in 2.0% of the patients in the bivalirudin group and in 2.4% in the heparin group (hazard ratio, 0.84; 95% CI, 0.60 to 1.19; P=0.33), major bleeding in 8.6% and 8.6%, respectively (hazard ratio, 1.00; 95% CI, 0.84 to 1.19; P=0.98), definite stent thrombosis in 0.4% and 0.7%, respectively (hazard ratio, 0.54; 95% CI, 0.27 to 1.10; P=0.09), and death in 2.9% and 2.8%, respectively (hazard ratio, 1.05; 95% CI, 0.78 to 1.41; P=0.76). CONCLUSIONS: Among patients undergoing PCI for myocardial infarction, the rate of the composite of death from any cause, myocardial infarction, or major bleeding was not lower among those who received bivalirudin than among those who received heparin monotherapy. (Funded by the Swedish Heart-Lung Foundation and others; VALIDATE-SWEDEHEART ClinicalTrialsRegister.eu number, 2012-005260-10 ; ClinicalTrials.gov number, NCT02311231 .).

Aprotinin reduces the antiplatelet effect of clopidogrel.

Aprotinin reduces bleeding and transfusion rates in patients undergoing coronary surgery while on clopidogrel. However, safety studies have indicated that aprotinin may have a possible adverse effect related to an increased incidence of thromboembolic events. We therefore studied the adenosinediphosphate (ADP) mediated platelet aggregation before and after administration of aprotinin in patients on clopidogrel. Fifteen clopidogrel-treated patients with acute coronary syndrome undergoing coronary surgery were studied. ADP-mediated platelet aggregation and platelet count ratio (%) were measured before and after a bolus dose [2 x 10(6) kallikrein inhibiting units (KIU)] of aprotinin. Aprotinin induced an increased aggregation in 11 of 15 patients (73%), and a decrease was registered in two patients (13%). The median (25th/75th percentile) ADP-mediated platelet aggregation before and after aprotinin was 84% (76/91) and 94% (86/97, P<0.01). Clopidogrel non-responders with >90% aggregation (n=4) had a median aggregation of 94.5% (91.5/97.5) vs. 82% (73/87, P<0.01) in the responders (n=11). The median increase in platelet aggregation after aprotinin was 8% (5/20) in the responders vs. 0% (-5.25/3, P<0.01) in the non-responders. Aprotinin increased ADP induced platelet aggregation from 84 to 94% in patients on clopidogrel, which corresponds to a median decrease in relative platelet inhibition of >50%.

Sirolimus-eluting coronary stents in small vessels

Background This prospective multicenter study compared angiographic in-lesion late lumen loss in de novo native coronary artery lesions (vessel diameter range 2.25-2.75 mm, length range z15 to V30 mm) 8 months after the implantation of a sirolimus-eluting stent with that of similar vessels with the same drug-eluting stent or a bare stent of the SIRIUS study (historical controls). Methods and Results One hundred one patients (study group) were matched and compared with 323 patients receiving the bare stent (bare control group) and with 350 receiving the Cypher stent (Cypher control group) in the SIRIUS trial. Mean in-lesion late loss in the study group was lower than that in the bare control group (0.20 versus 0.76 mm, P b .0001) and not inferior to that in the Cypher control group (0.27 mm, P = .3). Adverse event rates (death and myocardial infarction) were similar between groups. At 8 months, target lesion revascularization rates were 0% in the study group, 13.2% in the bare control group ( P b .001), and 4.6% in the Cypher control group ( P = .03). Conclusions The Cypher Bx Velocity stent was confirmed to be superior to the bare Bx Velocity stent in small coronary vessels in terms of in-lesion late loss 8 months after implantation. (Am Heart J 2006;151:1019.e121019.e7.) Rates of angiographic restenosis and target lesion revascularization (TLR) were found to be higher in small vessels (b2.5 mm in diameter) than in larger vessels 6 months after percutaneous transluminal coronary angioplasty or stenting1,2 and 1 year after stenting.3 Predictors of small vessel restenosis are diabetes, complex lesions, and long lesions.1,4,5 Although estenosis has not been conclusively linked to mortality, it can adversely affect quality of life.6 tents reduce restenosis by preventing recoil, but tissue growth renarrows the lumen significantly in approximately 20% of patients.7-12 Small vessel stenting has shown some advantages over balloon angioplasty randomized and nonrandomized trials but a higher risk for restenosis as compared with larger vessels.13-17 In recent years, stents eluting sirolimus or taxol have attenuated vascular hyperproliferation.18-25 Sirolimus prevents neointimal proliferation.26,27 The Cypher (sirolimus-eluting Bx Velocity) stent was compared with the bare Bx Velocity stent in the SIRIUS study...

Sirolimus-eluting coronary stents in small vessels.

BACKGROUND: This prospective multicenter study compared angiographic in-lesion late lumen loss in de novo native coronary artery lesions (vessel diameter range 2.25-2.75 mm, length range > or = 15 to < or = 30 mm) 8 months after the implantation of a sirolimus-eluting stent with that of similar vessels with the same drug-eluting stent or a bare stent of the SIRIUS study (historical controls). METHODS AND RESULTS: One hundred one patients (study group) were matched and compared with 323 patients receiving the bare stent (bare control group) and with 350 receiving the Cypher stent (Cypher control group) in the SIRIUS trial. Mean in-lesion late loss in the study group was lower than that in the bare control group (0.20 versus 0.76 mm, P < .0001) and not inferior to that in the Cypher control group (0.27 mm, P = .3). Adverse event rates (death and myocardial infarction) were similar between groups. At 8 months, target lesion revascularization rates were 0% in the study group, 13.2% in the bare control group (P < .001), and 4.6% in the Cypher control group (P = .03). CONCLUSIONS: The Cypher Bx Velocity stent was confirmed to be superior to the bare Bx Velocity stent in small coronary vessels in terms of in-lesion late loss 8 months after implantation.

Clinical benefit of small vessel stenting: one-year follow-up of the SISCA trial.

OBJECTIVE: To assess the long-term clinical benefit of elective stenting as compared with percutaneous transluminal coronary angioplasty (PTCA) in small coronary arteries. DESIGN: The Stenting in Small Coronary Arteries (SISCA) trial was a randomized trial comparing elective stenting with PTCA in coronary arteries with a reference diameter of 2.1-3.0 mm. The heparin-coated beStent was used. Control angiography was performed after 6 months, and the patients were followed clinically for 12 months. RESULTS: At 6 months the clinical outcome was significantly better in the stent group as compared with the PTCA group, with an event-free survival in 90.5 and 76.1% (p = 0.016), respectively. From 6 to 12 months, event-free survival was unchanged in both groups, demonstrating a sustained long-term clinical benefit of elective stenting. CONCLUSION: Angioplasty in small coronary arteries is associated with a favorable clinical outcome after 1 year. The clinical benefit of elective stenting using the Hepamed-coated beStent is maintained beyond 6 months, without any tendency towards late events. Thus, elective stenting should be considered as an option when treating small coronary arteries.