Subacute thrombosis with antiplatelet treatment in a non-selected population of intracoronary stents: incidence and predictors

INTRODUCTION: After coronary stenting, the incidence of subacute stent thrombosis have been reduced to 0% using aspirin and ticlopidine, in studies with selected populations and intracoronary ultrasounds. OBJECTIVE: To evaluate the incidence and predictors of subacute stent thrombosis in a nonselected population, using antithrombotic therapy. METHODS: We studied 285 stents, consecutively and successfully implanted in 268 lesions of 226 patients. We used high pressure balloon inflation without intracoronary ultrasound. Post-stenting protocol included aspirin and ticlopidine during four weeks with no anticoagulation. We defined subacute stent thrombosis as death, acute myocardial infarction myocardial infarction or angiographic occlusion of stent, with TIMI flow 0-1, after the first 24 hours and during the first month. RESULTS: Four patients presented events (1.7%): Three nonfatal myocardial infarction after discharge, with documented angiographic thrombosis of stent, and one death due to in-hospital myocardial infarction. All three non-fatal AMI, occurred in vessels less than 3 mm (p = 0.07) and in patients taking aspirin without ticlopidine (p < 0.001). After discharge, three (17%) of 18 patients with inadvertent discontinuation of ticlopidine presented subacute stent thrombosis, in contrast to none of 25 patients taking ticlopidine without aspirin. Excluded patients with discontinuation of ticlopidine, the incidence of subacute stent thrombosis was 0.5%. CONCLUSION: After intracoronary stenting in a nonselected population, using antithrombotic treatment with aspirin and ticlopidine, we may expect a rate of subacute stent thrombosis about 1%. Ticlopidine seems to have the main role in preventing subacute stent thrombosis, above all in predisposing circumstances as small vessels.     

Late stent thrombosis in patients receiving ticlopidine and aspirin after sirolimus-eluting stent implantation.

BACKGROUND: There is little information about the efficacy of ticlopidine plus aspirin after sirolimus-eluting stent (SES) implantation. METHODS AND RESULTS: The incidence of stent thrombosis was evaluated in 1,029 patients receiving ticlopidine and aspirin after SES deployment. Clinical follow-up was obtained in 98.9% (mean follow-up 17.0+/-7.9 months). Early stent thrombosis was observed in 5 patients (0.49%). There was 1 case each of late (0.1%) and very late stent thrombosis (0.1%). CONCLUSION: Late and very late stent thrombosis in Japanese patients receiving ticlopidine and aspirin after SES deployment occurs infrequently.     

Parameters of the tissue factor pathway with coumadin/dipyridamole versus ticlopidine as adjunct antithrombotic-drug regimen in coronary artery stenting.

A different rate and timing of subacute stent thrombosis after percutaneous coronary intervention was reported with various peri-interventional antithrombotic regimens. Next to platelet activation, coagulation triggered by tissue factor (TF) may play a key role in this process. Thirty-one consecutive patients with stable and unstable angina undergoing coronary stenting were randomly assigned to adjunct oral anticoagulation/anti-platelet therapy (coumadin, dipyridamole, aspirin and heparin; n = 16) or adjunct anti-platelet therapy with thienopyridin (ticlopidine, aspirin and heparin; n = 15). Antigen levels of plasma TF, total tissue factor pathway inhibitor (TFPI) and TFPI/ activated factor X (TFPI/FXa) complex were determined before and for up to 6 days after intervention by immunoassay. At baseline, significantly higher levels of plasma TF and TFPI/FXa were found in patients with unstable angina [TF, 161 pg/ml (126-191 pg/ml); TFPI/FXa, 7.8 ng/ml (6.1-9.6 ng/ml)] compared with stable angina [TF, 62 pg/ml (46-82 pg/ml), P < 0.0001; TFPI/FXa, 4.5 ng/ml (3-7.6 ng/ml), P= 0.003]. One hour after intervention, an increase of plasma TF and TFPI/FXa was seen in both treatment groups. In unstable angina patients, plasma levels of TF, TFPI and TFPI/FXa were more efficiently reduced by adjunct ticlopidine therapy compared with adjunct coumadin/dipyridamole. These data suggest reduced release of circulating TF by combined anti-platelet therapy with ticlopidine and aspirin after coronary artery stenting, which may-contribute to the lower incidence of subacute stent thrombosis previously observed.     

Usefulness of intracoronary angioscopy for elucidating the cause of subacute thrombosis after stenting

Stent thrombosis is rare with anti-platelet therapy, which consists of aspirin and ticlopidine as a post-stenting administration. A 77-year-old man had repeated stent thrombosis, which was not predicted by coronary angiography, despite using contemporary periprocedural anti-platelet therapy. Only intravascular fiberscopy was able to detect the cause of the stent thrombosis.     

Combination therapy with clopidogrel and aspirin after coronary stenting.

Combination antiplatelet therapy using aspirin and ticlopidine has been the standard of care for prevention of subacute thrombosis following coronary stent implantation. However, the use of ticlopidine is associated with a significant risk of adverse hematologic side effects. Clopidogrel is an inhibitor of ADP-induced platelet aggregation that has a better safety profile than ticlopidine. We examined the 30-day clinical outcome following coronary stent implantation in 253 consecutive patients treated with clopidogrel and aspirin. Follow-up was achieved in 99% of patients and four adverse events were documented. Two patients had angiographically confirmed subacute stent thrombosis (0.8%), and both of these patients underwent successful repeat angioplasty at the stent site. There were two patient deaths during follow-up (0. 8%). One was sudden within 1 week of stent placement and the other occurred in a patient with multisystem organ failure after an extensive myocardial infarction that antedated the stent procedure, with no clinical evidence for stent thrombosis. The combined frequency of subacute stent thrombosis and death was 1.6%. This is comparable to prior studies using the combination of ticlopidine and aspirin following stenting. Therefore, clopidogrel in combination with aspirin appears to be a safe and effective therapy in the prevention of subacute thrombosis following coronary stent implantation.     

Timing of coronary stent thrombosis in patients treated with prophylactic tirofiban

BACKGROUND: Acute and subacute stent thromboses (ASST) are the major thrombotic complications of coronary stenting. The time course of ASST seems to be related to the type of antithrombotic therapy (four days in patients treated with aspirin and coumadin compared to 12 hours with the use of aspirin and ticlopidine). In this report, we compared the timing of ASST in patients treated with aspirin, ticlopidine/clopidogrel, heparin and tirofiban with that in patients treated with the same drugs but without tirofiban. METHODS: Retrospective analysis of the Hermann intervention database between January 1997 and October 1999 was performed. We identified 13 patients who required reintervention in the first week after a successful coronary stenting ( 1 stent). Four patients were treated with tirofiban (Group 1) and 9 were not (Group 2). RESULTS: The median time from stent deployment to ASST was 7 hours (interquartile range, 2.5Eth 33 hours) in group 2 compared to 84.5 hours (interquartile range, 56Eth 124.5 hours) in group 1. The mean time from stent deployment to ASST was 90.3 +/- 43.1 hours in group 1 versus 12.8 +/- 15.3 hours in group 2 (p = 0.0005). All episodes of ASST occurred 3 days in patients treated with tirofiban, whereas they occurred in the first 2 days in all patients not treated with tirofiban. CONCLUSION: Prophylactic tirofiban treatment delays the time to stent thrombosis after successful coronary artery stent implantation for more than two days. Patients at high risk for stent thrombosis treated with short-acting glycoprotein IIb/IIIa platelet receptor inhibitors may warrant close follow-up during the first week after stenting.     

Simultaneous subacute stent thrombosis of two sirolimus-eluting stents in a patient treated by ReoPro, thrombus aspiration and triple anti-platelet agents

Effective anti-platelet treatment has a key role in the prevention of stent thrombosis in the drug-eluting stent (DES) era. However, despite of the use of anti-platelet agents, stent thrombosis occurs in approximately 1% of patients, with an increased likelihood of occurrence in high-risk patients or complex lesion subset of patients [1-4]. According to the previous report, triple anti-platelet therapy (aspirin+clopidogrel+cilostazol) seemed to be more effective in preventing thrombotic complications after stenting than dual anti-platelet agent [5]. But, in this report, we present a patient with subacute stent thrombosis (ST) involving two different arteries simultaneously under the use of triple anti-platelet regimen.     

The MUST Trial: Acute Results and Six-Month Clinical Follow-up

Coronary stenting is now an established technique which is associated with improved acute and long-term results and prevents restenosis in comparison to balloon angioplasty in selected patients. However, subacute thrombosis and vascular complications associated with conventional anticoagulant therapy (warfarin for one month, with 4D5 days of IV heparin) remain of concern. By means of a prospective, multi-center registry, we sought to demonstrate that the use of ticlopidine and aspirin as the sole post-stenting treatment was safe by reducing bleeding complications without increasing the risk of major cardiac events. A total of 260 patients with stable and unstable angina and a short, single de novo lesion were enrolled in this registry. Successful stent deployment without ultrasound guidance was achieved in 259 patients. All patients were treated with aspirin 3 100 mg daily for 6 months and ticlopidine 250 to 500 mg daily according to body weight for 1 month. The primary endpoint was safety, defined by the occurrence of death, myocardial infarction (MI), coronary bypass surgery (CABG) or repeat angioplasty (PTCA) within 30 days of the procedure, in addition to subacute stent thrombosis and bleeding and vascular complications within 30 days of the intervention. During hospital stay there were no deaths; 8 patients experienced MI, 1 patient underwent urgent CABG and 4 patients had repeat PTCA. Therefore, the clinical success rate was 96.0%. Bleeding complications requiring blood transfusion or vascular repair occurred in 2 patients. Treatment was discontinued in one patient because of mild reversible leucopenia. At 6 months, event-free survival was 90.3%. Major events involved CABG in 4 patients and a second PTCA at the same site in 14 patients. The target vessel revascularization rate at 6 months was 6.2%. This study demonstrates that Palmaz-Schatz stenting of single de novo lesions with length < 15 mm, without ultrasound guidance but with the routine use of high-pressure balloon dilatation, and with ticlopidine and aspirin as the sole treatment post intervention, is feasible and safe both in terms of clinical outcome and hematologic adverse side-effects. This registry demonstrates that six-month event-free survival exceeding 90% can be achieved.     

Subacute thrombosis after coronary stenting occurring with resistance to ticlopidine

A 79-year-old man underwent stent implantation from the proximal site to the left main trunk with one bare metal stent after rotation atherectomy. He received 200 mg/day ticlopidine and 200 mg/day aspirin from 2 days pre-stenting. Subacute thrombosis occurred 5 days after coronary stenting. We performed a test of platelet aggregation one month after the commencement of dual antiplatelet therapy and the test showed no response to ticlopidine in this case. An increased dose of ticlopidine was not effective for suppressing platelet aggregation. We report a case of subacute stent thrombosis which is related to ticlopidine resistance.     

Comparison of cilostazol versus ticlopidine therapy after stent implantation.

The aim of this study was to evaluate the efficacy of cilostazol for prevention of stent thrombosis compared with ticlopidine. Cilostazol is a potent antiplatelet agent with less serious side effects. However, few data are available about the effect of cilostazol in preventing stent thrombosis after coronary stent implantation. Four hundred ninety patients selected for elective stent placement were randomized to receive aspirin plus ticlopidine (n = 243) or aspirin plus cilostazol (n = 247) for 1 month. Clinical and laboratory evaluations were performed at regular interval. There were no differences in baseline characteristics between the 2 groups. During the first 30 days after stent implantation, major cardiac events or adverse drug effects were similar between the 2 groups: ticlopidine (2.9%) vs cilostazol (1.6%) group, p = NS; stent thrombosis (0.4% vs 0.8%, p = NS, respectively), myocardial infarction (0.4% vs 0.8%, p = NS), severe leukopenia (1.2% vs 0%, p = NS), severe thrombocytopenia (0.4% vs 0%, p = NS), and cerebral hemorrhage (0.4% vs 0%, p = NS). Adverse effects led to drug withdrawal in 7 patients in the ticlopidine group (2.9%) and in 5 in the cilostazol group (2.0%). There was no death during the follow-up period. Thus, aspirin plus cilostazol may be an effective antithrombotic regimen with comparable results to aspirin plus ticlopidine after elective coronary stenting.     

Randomized comparison of cilostazol vs ticlopidine for antiplatelet therapy after coronary stenting.

BACKGROUND: Cilostazol and ticlopidine are commonly prescribed for prevention of thrombosis after coronary stenting, but few studies have compared them. METHODS AND RESULTS: In the present study 642 patients who underwent stenting were randomized to treatment either with cilostazol + aspirin (C group, 321 patients) or ticlopidine + aspirin (T group, 321 patients). Quantitative coronary angiography (QCA) was performed immediately after stenting and at the 6-month follow-up. Treatment was continued until follow-up angiography. Baseline patient characteristics did not differ significantly. With the exception of a higher rate of stenting in a venous graft in the C group, there were no differences in angiographic characteristics or stent type. Baseline QCA analysis of the reference diameter, minimal lumen diameter (MLD) showed no significant differences. Follow-up QCA analysis of the MLD showed no significant differences. There were also no differences in restenosis or target lesion revascularization rates, or in the incidence of adverse reactions. However, the rate of subacute thrombosis (SAT) was significantly higher in the C group than in the T group (2% vs 0.3%, p=0.02). CONCLUSION: In the present study there was a similar restenosis rate with cilostazol or ticlopidine, but the rate of SAT was significantly higher with cilostazol. There was no significant difference in adverse reactions.     

Dual antiplatelet therapy with clopidogrel and aspirin after carotid artery stenting.

BACKGROUND: Carotid artery stenting is being used as an alternative to carotid endarterectomy, both within the context of clinical trials and in non-surgical candidates. Though stenting is known to activate platelets, the role of antithrombotic therapy in carotid stenting has not been fully characterized. METHODS AND RESULTS: Consecutive patients (n = 162) were followed in a single-center carotid stent registry. The cumulative rate of 30-day death, stroke, transient ischemic attack and myocardial infarction in those patients receiving a thienopyridine was determined, as were rates of stent thrombosis and intracranial hemorrhage. The mean age of the patients was 70.3 years and there was an extremely high prevalence of cardiovascular comorbidities, including 40% with unstable angina. The carotid lesion was symptomatic in 59% of patients. The average pre-treatment stenosis was 83%. The cumulative 30-day rate of death, stroke, transient ischemic attack and myocardial infarction was 5.6%. Specifically, in the patients who received ticlopidine (n = 23), the rate was 13%, versus 4.3% in the patients who received clopidogrel (n = 139) (p = 0.01). In this series, there were no cases of stent thrombosis and 1 intracranial hemorrhage. CONCLUSION: Dual antiplatelet therapy with clopidogrel plus aspirin in patients receiving carotid artery stents is associated with a low rate of ischemic events. Furthermore, clopidogrel appears superior to ticlopidine. Thus, our findings lend support to the dual antiplatelet strategy of clopidogrel plus aspirin for patients undergoing carotid artery stenting.     

Triple versus dual antiplatelet therapy after coronary stenting: impact on stent thrombosis.

OBJECTIVES: We evaluated safety and efficacy of triple antiplatelet therapy with aspirin, clopidogrel, or ticlopidine and cilostazol after coronary stenting. BACKGROUND: Triple antiplatelet therapy might have beneficial effect to prevent thrombotic complications in patients undergoing coronary stenting. METHODS: Patients undergoing successful coronary stenting were divided into dual antiplatelet therapy (aspirin plus clopidogrel or ticlopidine, group I, n = 1,597) and triple antiplatelet therapy (aspirin plus clopidogrel or ticlopidine plus cilostazol, group II, n = 1,415) groups. The primary end point included death, myocardial infarction, target lesion revascularization, or stent thrombosis within 30 days. The secondary end point was side effects of study drugs, including major bleeding, vascular complication, hepatic dysfunction, and hematological complications. RESULTS: Multi-vessel stenting and the use of long stents were more prevalent in group II than in group I. The primary end point was 0.8% in group I and 0.3% in group II (p = 0.085). Stent thrombosis within 30 days was significantly lower in group II (n = 1, 0.1%) than in group I (n = 9, 0.5%; p = 0.024). The independent predictors of stent thrombosis were primary stenting (odds ratio [OR] 7.9, 95% confidence interval [CI] 2.0 to 30.8, p = 0.003) and triple therapy (OR 0.12, 95% CI 0.015 to 0.98, p = 0.048). The overall adverse drug effects, including major bleeding, neutropenia, and thrombocytopenia, were no different between two groups (1.8% vs. 2.6%, p = 0.104). CONCLUSIONS: Compared with the dual antiplatelet regimen, triple antiplatelet therapy seemed to be more effective in preventing thrombotic complications after stenting without an increased risk of side effects. Triple antiplatelet therapy might be safely applied in patients or lesions with a high risk of stent thrombosis.     

Clopidogrel versus ticlopidine after intracoronary stent placement

OBJECTIVES

The study compared the safety and efficacy of ticlopidine with clopidogrel in patients receiving coronary stents.

BACKGROUND

Stent thrombosis is reduced when ticlopidine is administered with aspirin. Clopidogrel is similar to ticlopidine in chemical structure and function but has fewer side effects; few data are available about its use in stent patients.

METHODS

We compared 30-day event rates in 500 consecutive coronary stent patients treated with aspirin and clopidogrel (300 mg loading dose immediately prior to stent placement, and 75 mg/day for 14 days) to 827 consecutive stent patients treated with aspirin and ticlopidine (500 mg loading dose and 250 mg twice daily for 14 days).

RESULTS

Patients treated with clopidogrel had more adverse clinical characteristics including older age, more severe angina, and more frequent infarction within the prior 24 h. Nonetheless, mortality was 0.4% in clopidogrel patients versus 1.1% in ticlopidine patients; nonfatal myocardial infarction occurred in 0% versus 0.5%, stent thrombosis in 0.2% versus 0.7%, bypass surgery or repeat angioplasty in 0.4% versus 0.5%, and any event occurred in 0.8% versus 1.6% of patients, respectively (p = NS). Based on the observed 30-day event rate of 1.6% with ticlopidine, the statistical power of the study was 43% to detect an even rate of 0.5% with clopidogrel, and 75% to detect an event rate with of 4% with clopidogrel, with a p value of 0.05.

CONCLUSIONS

These data indicate that clopidogrel can be safely substituted for ticlopidine in patients receiving coronary stents.     

Coronary intervention with a heparin-coated stent and aspirin only

OBJECTIVES: To determine the safety and efficacy of a post-stenting anti-platelet regimen of aspirin without additional ticlopidine or clopidogrel after successful heparin-coated stent implantation. METHODS: A prospective, non-randomized, multi-center pilot study of patients undergoing percutaneous coronary intervention, including those with acute coronary syndromes and small vessels with one-month clinical follow-up, was undertaken. Patients received a heparin-coated stent and were treated with aspirin only. RESULTS: Over a period of 6 months, a total of 122 patients were recruited in 6 centers. Their mean age was 57.2 10.0 years, 79% were male and 31% had unstable angina. Most (75%) had single-vessel disease, predominantly of the left anterior descending artery (51%), with a mean reference diameter of 2.44 mm 0.44 mm at baseline and 2.48 0.41 mm post stenting. At a 1-month clinical follow-up, no major adverse cardiovascular events (including subacute stent thrombosis) had occurred. Five patients were readmitted to hospital for symptoms unrelated to the interventional procedure. CONCLUSIONS: Heparin-coated stent implantation using an antiplatelet regimen of aspirin only, appears to be safe and feasible. A randomized trial of a larger number of patients appears warranted.     

Coronary stent thrombosis: time course and clinical outcome

The current clinical practice of stent implantation has changed over the last few years. We analysed the incidence and time course of stent thrombosis in patients undergoing successful coronary angioplasty and stenting over the last three years. All the patients were treated with aspirin and ticlopidine. A total of 13 patients experienced stent thrombosis. The mean age was 52+/-12 years; 12 were smokers and 10 had a recent history of myocardial infarction. None of these patients had received abciximab. The median time from stent implantation to stent thrombosis was 10 hours, with all the stent occlusions occurring within 18 hours of stent implantation procedure. All the patients underwent a repeat intervention at a median time of 30 minutes after the clinical suspicion of stent occlusion. On follow-up of 1 to 24 months, three patients developed reocclusion. In the present era of coronary angioplasty and stenting, when interventional procedures are not pre-planned and patients are treated with aspirin and ticlopidine or clopidogrel at the time of stent implantation, the incidence of stent thrombosis is low; it is seen mainly in patients with recent myocardial infarction, majority of them being smokers, and occurs within 18 hours in all the patients.     

Effects of cilostazol on angiographic restenosis after coronary stent placement

This study evaluates the impact of cilostazol on post-stenting restenosis. Cilostazol is a potent antiplatelet agent with antiproliferative properties. Few data are available about the effect of cilostazol on poststenting restenosis. Four hundred nine patients (494 lesions) who were scheduled for elective stenting were randomized to receive aspirin plus ticlopidine (group I, n = 201, 240 lesions) or aspirin plus cilostazol (group II, n = 208, 254 lesions), starting 2 days before stenting. Ticlopidine was given for 1 month and cilostazol for 6 months. Follow-up angiography was performed at 6 months, and clinical evaluation at regular intervals. Baseline characteristics were similar between the 2 groups. The procedural success rate was 99.6% in group I and 100% in group II. There were no cases of stent thrombosis after stenting. Angiographic follow-up was performed in 380 of the 494 eligible lesions and the angiographic restenosis rate was 27% in group I and 22.9% in group II (p = NS). However, diffuse type in-stent restenosis was more common in group I than in group II (54.2% vs 26.8%, respectively, p <0.05). In diabetic patients, the angiographic restenosis rate was 50% in group I and 21.7% in group II (p <0.05). Clinical events during follow-up did not differ between the 2 groups. In conclusion, aspirin plus cilostazol seems to be an effective antithrombotic regimen with comparable results to aspirin plus ticlopidine, but it does not reduce the overall angiographic restenosis rate after elective coronary stenting.     

Adjunctive therapies in the cath lab. Subacute stent thrombosis developing twelve days after discontinuation of ticlopidine treatment

The two structurally related thienopyridines, ticlopidine and clopidogrel in addition to aspirin, have become the standard regimen for prevention of subacute thrombosis (SAT) after coronary stent implantation. Although both regimens are highly effective, ticlopidine suffers from severe hematologic side effects. Recent trials encourage shorter duration of therapy with these agents. However, the optimal duration of antiplatelet therapy after stenting is still not clear. We report a case of SAT developing 12 days after discontinuation of 2 weeks of aspirin plus ticlopidine therapy. We believe that the present data are still not clear regarding the optimum duration of antiplatelet therapy after stenting.     

Coronary artery stenting in unstable angina pectoris: a comparison with stable angina pectoris

OBJECTIVE: To compare early complication rates in unselected cases of coronary artery stenting in patients with stable v unstable angina. SETTING: Tertiary referral centre. PATIENTS: 390 patients with stable angina pectoris (SAP) and 306 with unstable angina (UAP). Patients treated for acute myocardial infarction (primary angioplasty) or cardiogenic shock were excluded. INTERVENTIONS: 268 coronary stents were attempted in 211 patients (30.3%). Stents used included AVE (63%), Freedom (14%), NIR (7%), Palmaz-Schatz (5%), JO (5%), and Multilink (4%). Intravascular ultrasound was not used in any of the cases. All stented patients were treated with ticlopidine and aspirin together with periprocedural unfractionated heparin. RESULTS: 123 stents were successfully deployed in 99 SAP patients v 132 stents in 103 UAP patients. Failed deployment occurred with nine stents in SAP patients, v four in UAP patients (NS). Stent thrombosis occurred in four SAP patients and 11 UAP patients. Multivariate analysis showed no relation between stent thrombosis and clinical presentation (SAP v UAP), age, sex, target vessel, stent length, or make of stent. Stent thrombosis was associated with small vessel size (p < 0.001) and bailout stenting (p = 0.01) compared with elective stenting and stenting for suboptimal PTCA, with strong trends toward smaller stent diameter (p = 0.052) and number of stents deployed (p = 0.06). Most stent thromboses occurred in vessels < 3 mm diameter. CONCLUSIONS: Coronary artery stenting in unstable angina is safe in vessels >/= 3 mm diameter, with comparable initial success and stent thrombosis rates to stenting in stable angina.     

Usefulness of cilostazol versus ticlopidine in coronary artery stenting

A combination of ticlopidine and aspirin has been accepted as the standard antithrombotic regimen after coronary stenting. However, ticlopidine poses serious side effects such as neutropenia or thrombocytopenia. Cilostazol, a cyclic adenosine monophosphate phosphodiesterase inhibitor, is a novel antiplatelet agent with vasodilatory properties. We compared the efficacy and safety of cilostazol plus aspirin (C+A) with ticlopidine plus aspirin (T+A) in elective coronary stenting. Three hundred patients were randomly assigned to receive C+A or T+A 2 days before stenting. The primary end point was a composite of angiographic stent thrombosis, or major cardiac events (death, myocardial infarction, bypass surgery, repeat intervention) at 30 days. The secondary end points were bleeding vascular complications, neutropenia, thrombocytopenia, or side effects requiring discontinuation of the drugs at 30 days. The primary end point was reached in 1.4% in the C+A group and 2.0% in the T+A group (p = 1.0). The rate of bleeding vascular complications was 1.4% in the C+A group and 2.0% in the T+A group (p = 1.0). The rate of drug-related side effects was not statistically different between the 2 groups but slightly higher in the T+A group than in the C+A group (2.7% vs 0.7%, p = 0.37). However, neutropenia was seen in 2 patients only in the T+A group. As a poststenting antithrombotic, C+A is as effective as T+A in preventing major cardiac events including stent thrombosis, and safer in that it does not cause neutropenia despite the fact that there is no statistical difference in the incidence of adverse effects and complications.