Tailored antiplatelet agent medication in clopidogrel hyporesponsive patients before stent-assisted coiling: single-center experience (original) (raw)

Low-Dose Prasugrel in Patients with Resistance to Clopidogrel for the Treatment of Cerebral Aneurysms

Neurointervention, 2018

Thromboembolism is one of the major complications of stent assisted coiling in treatment of cerebral aneurysm. Clopidogrel resistance is so common and prasugrel is more effective in its rapid and potent effect. We investigated changes in the value of P2Y12 resistance unit (PRU) when prasugrel was administered to patients with clopidogrel resistance. One hundred mg of aspirin and 75 mg of clopidogrel were administered for 5 days before the procedure, and PRU were examined. The resistance to clopidogrel was defined as the inhibition of PRU was less than 20%. PRU was re-examined after loading 20 mg of prasugrel. We treated 98 consecutive patients between January 2018 and July 2018, and 24 patients (24.5%) had resistance to clopidogrel. Nineteen patients were female. The mean PRU value at admission was 238.5±36.9 and the percentage inhibition value was 4.8±6.3%. After the use of prasugrel, the mean PRU and percentage inhibition values were measured as 124.9±49.9 and 48.0±19.24, respecti...

Clopidogrel Resistance Is Associated with Thromboembolic Complications in Patients Undergoing Neurovascular Stenting

American Journal of Neuroradiology, 2012

BACKGROUND AND PURPOSE: Antiplatelet drug resistance has been associated with thromboembolic complications in patients after coronary stent placement. It has not been well-studied in patients who have neurovascular stent-placement procedures. This study aimed to analyze the relationship between antiplatelet drug resistance and neurovascular stent-placement complications. MATERIALS AND METHODS: A prospective data base of all patients treated at our institution was used to identify patients with neurovascular stent-placement procedures. During a 4.5-year period, all patients undergoing neurovascular stent placement were evaluated for aspirin and clopidogrel resistance by using the VerifyNow assay. During an observational phase, all patients received 75 mg of clopidogrel and aspirin (group A). During the intervention phase (group B), patients were given additional clopidogrel on the basis of the clopidogrel resistance assay. We assessed the development of thromboembolic complications within 30 days of the procedure in patients who were resistant-versus-nonresistant to clopidogrel. RESULTS: Of 96 patients who had neurovascular stent placement, 5.2% were resistant to aspirin and 36.5% were resistant to clopidogrel. Periprocedural thromboembolic complications were seen in 7 patients (7.3%). In a multivariate logistic regression model, clopidogrel resistance, higher diastolic blood pressure, and lack of statin use were significantly associated with periprocedural thromboembolic complication. There was a nonsignificant decrease in thromboembolic complications in patients whose clopidogrel dosage was tailored to the assay. CONCLUSIONS: In our series, clopidogrel resistance was associated with increased periprocedural thromboembolic complications from neurovascular stent-placement procedures. Targeting the clopidogrel dose to platelet inhibition assays may improve clinical outcomes and requires further study. ABBREVIATIONS: ACT ϭ activated clotting time; ARU ϭ aspirin reaction units; LTA ϭ light transmittance aggregometry; PCI ϭ percutaneous cardiovascular interventions; PRU ϭ P2Y12 reaction units

Clopidogrel resistance "Live" � the risk of stent thrombosis should be evaluated before procedures

Thrombosis Journal, 2009

Every year, millions of people undergo percutaneous coronary intervention (PCI) with intracoronary stent implantation. A patient from the PRAGUE-8 trial (Optimal pre-PCI clopidogrel loading: 600 mg before every coronary angiography vs. 600 mg in the cath-lab only for PCI patients) is described who suffered from acute stent thrombosis. This patient did not have any relevant inhibition of platelet activation even after the 600 mg dose of clopidogrel. Dose uptitration would have been ineffective. New P2Y 12 receptor inhibitors are desperately needed. In the light of recently published data, the use of prasugrel may be considered as an alternative.

High Maintenance Dosage of Clopidogrel is Associated with a Reduced Risk of Stent Thrombosis in Clopidogrel-Resistant Patients

American Journal Cardiovascular Drugs, 2010

Background: Stent thrombosis remains an important complication after stent implantation, despite the use of dual antiplatelet therapy with aspirin (acetylsalicylic acid) and clopidogrel. Several studies have shown an increased risk of thrombotic events in patients with resistance to clopidogrel. Some recent studies have suggested that a higher clopidogrel maintenance dosage could enhance ex vivo platelet inhibition and thereby overcome resistance to clopidogrel. Objectives: To investigate whether a higher clopidogrel maintenance dosage is associated with a reduced risk of stent thrombosis after percutaneous coronary intervention (PCI) in clopidogrel-resistant patients and to evaluate the frequency of hemorrhagic accidents that could be associated with a high clopidogrel maintenance dosage. Methods: An observational study was performed in 52 consecutive clopidogrel-resistant patients (resistance defined according to adenosine diphosphate-induced platelet aggregation assessment) who underwent a PCI with stenting at a tertiary referral center (Toulouse University Hospital, France). All patients received a clopidogrel loading dose of 300 mg, then 32 patients received a clopidogrel maintenance dosage of 75 mg day (patients admitted between 2004-5) and 20 patients received 150 mg day (patients admitted in 2006). We compared the occurrence of definite stent thrombosis and hemorrhagic accidents between these two groups, using a regression model. Results: Among the patients treated with clopidogrel 75 mg day, 26 (81.3%) had definite stent thrombosis versus seven (35.0%) treated with 150 mg day (adjusted relative risk [RR] 2.46; 95% CI 1.63, 2.76; p = 0.002). The risk of major adverse cardiac events (MACE) was also significantly lower in patients treated with 150 mg day (adjusted RR 2.63; 95% CI 1.82, 2.82; p = 0.001). There was no significant difference between the two groups regarding hemorrhagic accidents. Conclusion: Our data suggest that a high maintenance dosage of clopidogrel (150 mg day) is associated with a reduced risk of definite stent thrombosis and MACE compared with a maintenance dosage of 75 mg day. The frequency of hemorrhagic accidents was similar between the two groups, underlining a positive benefitrisk ratio of this strategy in clopidogrel-resistant patients. These findings deserve confirmation in a prospective, well conducted study.

Incidence of cerebral ischemic events after discontinuation of clopidogrel in patients with intracranial aneurysms treated with stent-assisted techniques

Journal of Neurosurgery, 2012

Object The optimal antiplatelet medication protocol for prevention of thrombotic complications after stent-assisted coil embolization of cerebral aneurysms is unclear. Early cessation of antiplatelet agents may be associated with an increased risk of cerebral ischemic events. In this study, the authors assess the incidence of stroke or transient ischemic attack (TIA) following discontinuation of a 6-week course of clopidogrel in patients with cerebral aneurysms treated with stent-assisted techniques. Methods A retrospective review was conducted in all patients with cerebral aneurysms undergoing stent-assisted coil embolization or stent-in-stent flow diversion at the University of Iowa during a 24-month period. The antiplatelet protocol was 81 mg aspirin and 75 mg clopidogrel daily for 6 weeks, followed by 325 mg aspirin daily indefinitely. The incidence of stroke or TIA was determined by a retrospective review of medical records generated during a 3-month period following discontinu...

The clopidogrel resistance can be attenuated with triple antiplatelet therapy in patients undergoing drug-eluting stents implantation

International Journal of Cardiology, 2009

Background: Triple antiplatelet therapy may have a beneficial effect on prevention of thrombotic complication in patients undergoing coronary stenting. We investigated the prevalence of aspirin and clopidogrel resistance in patients treated with dual and triple antiplatelet regimen after percutaneous coronary intervention (PCI) with drug-eluting stents (DES). Methods: A total of 400 consecutive patients underwent successful PCI with DES were randomly assigned to therapy with dual antiplatelet regimens (aspirin plus clopidogrel, Group I, n = 200) and triple antiplatelet regimens (aspirin plus clopidogrel plus cilostazol, Group II, n = 200) At two weeks after PCI, aspirin and clopidogrel resistance were assayed in 379 patients (Group I, n = 186; Group II, n = 193) by using the VerifyNow System. Results: In Group I, 21 (11.3%) patients had aspirin resistance and 74 (40.0%) had clopidogrel resistance. In Group II, 19 (9.8%) were resistant to aspirin and 38 (19.7%) to clopidogrel. The aspirin reaction unit (ARU) was not significantly different between groups (448 ± 67 vs. 439 ± 64, P = 0.200), but the percent inhibition of clopidogrel was higher in Group II (41.4 ± 24.3%,) comparing with that of Group I (26.5 ± 18.7%, P b 0.001). Conclusion: With triple antiplatelet therapy, the prevalence of clopidogrel resistance can be attenuated in patients undergoing PCI with DES.

Pharmacogenetic approach to clopidogrel resistance: recurrent stent thrombosis in two brother

2014

Clopidogrel, is the antiplatelet treatment choice for prevention of thrombosis after coronary stent implantation. However, despite the use of clopidogrel, a considerable number of patients continue to have stent thrombosis. There is a growing degree of evidence that recurrence of ischemic complications may be attributed to poor response of clopidogrel. It is noteworthy to elucidate the mechanisms leading to poor clopidogrel effects. We reportrecurrent stent thrombosiswith possible clopidogrel resistanceand aimed to discuss the mechanisms of clopidogrel resistance in the light of the medical literature.

Effect of prasugrel versus clopidogrel on outcomes among patients with acute coronary syndrome undergoing percutaneous coronary intervention without stent implantation: A TRial to assess Improvement in Therapeutic Outcomes by optimizing platelet inhibitioN with prasugrel (TRITON)–Thrombolysis in ...

American Heart Journal, 2009

Prasugrel led to a significant reduction in ischemic cardiovascular events among patients with acute coronary syndrome (ACS) undergoing percutaneous coronary intervention (PCI) with stent implantation compared to clopidogrel. Whether this benefit extends to patients undergoing PCI without stent implantation is unknown.In TRial to assess Improvement in Therapeutic Outcomes by optimizing platelet inhibitioN with prasugrel (TRITON)-Thrombolysis in Myocardial Infarction (TIMI) 38, patients (n = 13 608) undergoing PCI for ACS were randomized to aspirin plus clopidogrel or prasugrel. This postrandomization analysis of a prespecified subgroup was restricted to patients who underwent PCI without stent implantation (n = 569).Patients who underwent PCI without stent implantation were older and had a higher incidence of hypertension, diabetes, prior myocardial infarction (MI), prior coronary artery bypass (CABG) surgery, and renal dysfunction than patients who underwent stent implantation. In the group that did not undergo stent implantation, baseline characteristics were similar between patients receiving clopidogrel and prasugrel. The composite of cardiovascular death, nonfatal MI, and nonfatal stroke occurred in 14.2% of patients receiving prasugrel and 17.1% of patients receiving clopidogrel (HR 0.82, P = .27). There were significant reductions favoring prasugrel in the rates of urgent target vessel revascularization (TVR; HR 0.46, P = .040) and any TVR (HR 0.40, P = .009) and a trend toward a reduction in the incidence of nonfatal MI (HR 0.65, P = .11). CABG-related TIMI major bleeding was more frequent among patients receiving prasugrel. There were no significant interactions between treatment and PCI type.Among ACS patients who underwent PCI without stent implantation, prasugrel therapy tended to reduce clinical ischemic events and to increase bleeding events to a similar magnitude as among patients who received stents.