Results indicated that some PFTs may have some prognostic utility , i.e. a trend for more clinical events to be associated with groups classified as ' aspirin resistant ' .
Study -level effect sizes were generally small and absolute outcome risk was not substantially different between ' aspirin resistant ' and ' aspirin sensitive ' design ations .
Based on assumptions of PFTs being able to accurately identify patients at high risk of clinical events and such patients benefiting from treatment modification , the economic model found that a test-treat strategy was likely to be cost-effective .
However , neither assumption is currently evidence based .
BACKGROUND The use of aspirin is well established for secondary prevention of cardiovascular disease .
However , a proportion of patients suffer repeat cardiovascular events despite being prescribed aspirin treatment .
It is uncertain whether or not this is due to an inherent inability of aspirin to sufficiently modify platelet activity .
This report aims to investigate whether or not insufficient platelet function inhibition by aspirin ( ' aspirin resistance ' ) , as defined using platelet function tests ( PFTs ) , is linked to the occurrence of adverse clinical outcomes , and further , whether or not patients at risk of future adverse clinical events can be identified through PFTs .
OBJECTIVES To review systematic ally the clinical effectiveness and cost-effectiveness evidence regarding the association between PFT design ation of ' aspirin resistance ' and the risk of adverse clinical outcome ( s ) in patients prescribed aspirin therapy .
To undertake exploratory model-based cost-effectiveness analysis on the use of PFTs .
Bedside monitoring to adjust antiplatelet therapy for coronary stenting.
BACKGROUND Patients ' responses to oral antiplatelet therapy  are subject to variation . Bedside monitoring offers the opportunity to improve outcomes after coronary stenting by individualizing therapy . METHODS We r and omly assigned 2440 patients scheduled for coronary stenting at 38 centers to a strategy of platelet-function monitoring  , with drug adjustment in patients who had a poor response to antiplatelet therapy , or to a conventional strategy without monitoring and drug adjustment . The primary end point was the composite of death , myocardial infa rct ion , stent thrombosis , stroke , or urgent revascularization 1 year after stent implantation . For patients in the monitoring group , the  VerifyNow P2Y12 and aspirin point-of-care assays were used in the catheterization laboratory before stent implantation and in the outpatient clinic 2 to 4 weeks later . RESULTS In the monitoring group , high platelet reactivity in patients taking clopidogrel ( 34.5 % of patients ) or aspirin ( 7.6 % ) led to the administration of an additional bolus of clopidogrel , prasugrel , or aspirin along with glycoprotein IIb/IIIa inhibitors during the procedure . The primary end point occurred in 34.6 % of the patients in the monitoring group , as compared with 31.1 % of those in the conventional-treatment group ( hazard ratio , 1.13 ; 95 % confidence interval [ CI ] , 0.98 to 1.29 ; P=0.10 ) . The main secondary end point , stent thrombosis or any urgent revascularization , occurred in 4.9 % of the patients in the monitoring group and 4.6 % of those in the conventional-treatment group ( hazard ratio , 1.06 ; 95 % CI , 0.74 to 1.52 ; P=0.77 ) . The rate of major bleeding events did not differ significantly between groups . CONCLUSIONS This study showed no significant improvements in clinical outcomes with platelet-function monitoring and treatment adjustment for coronary stenting , as compared with st and ard antiplatelet therapy without monitoring . ( Funded by Allies in Cardiovascular Trials Initiatives and Organized Networks and others ; A RCT IC Clinical Trials.gov number , NCT00827411 . )
Results indicated that some PFTs may have some prognostic utility , i.e. a trend for more clinical events to be associated with groups classified as ' aspirin resistant ' .
Study -level effect sizes were generally small and absolute outcome risk was not substantially different between ' aspirin resistant ' and ' aspirin sensitive ' design ations .
Based on assumptions of PFTs being able to accurately identify patients at high risk of clinical events and such patients benefiting from treatment modification , the economic model found that a test-treat strategy was likely to be cost-effective .
However , neither assumption is currently evidence based .
BACKGROUND The use of aspirin is well established for secondary prevention of cardiovascular disease .
However , a proportion of patients suffer repeat cardiovascular events despite being prescribed aspirin treatment .
It is uncertain whether or not this is due to an inherent inability of aspirin to sufficiently modify platelet activity .
This report aims to investigate whether or not insufficient platelet function inhibition by aspirin ( ' aspirin resistance ' ) , as defined using platelet function tests ( PFTs ) , is linked to the occurrence of adverse clinical outcomes , and further , whether or not patients at risk of future adverse clinical events can be identified through PFTs .
OBJECTIVES To review systematic ally the clinical effectiveness and cost-effectiveness evidence regarding the association between PFT design ation of ' aspirin resistance ' and the risk of adverse clinical outcome ( s ) in patients prescribed aspirin therapy .
To undertake exploratory model-based cost-effectiveness analysis on the use of PFTs .