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 .
Prehospital triple antiplatelet therapy in patients with acute ST elevation myocardial infarction leads to better platelet aggregation inhibition and clinical outcome than dual antiplatelet therapy
Objective To assess whether prehospital initiation of high-dose tirofiban in addition to high-dose clopidogrel results in more adequate inhibition of platelet aggregation ( IPA ) and better clinical outcome after primary percutaneous coronary intervention ( PCI ) . Methods Prespecified two-centre sub study of the prospect i ve , international , multicentre , placebo controlled Ongoing Tirofiban in Myocardial Infa rct ion Evaluation trial 2 ( On-TIME-2 trial ) . 648 of 964 ( 67 % ) patients in the On-TIME-2 trial with ST elevation myocardial infa rct ion undergoing primary PCI were studied . Pre-PCI IPA after early prehospital initiation of high-bolus dose ( 25 μg/kg ) tirofiban was compared to placebo in addition to acetylsalicylic acid , unfractionated heparin and 600 mg clopidogrel .  Results IPA was measured at a median of 60 min after study medication administration . In all four tests : Fe induced platelet aggregation , ADP induced platelet aggregation , platelet function analyser (PFA)-100 ( collagen – epinephrine and collagen – ADP cartridge ) IPA was higher in patients pretreated with high-dose tirofiban ( p<0.001 for all tests ) , even after > 74 min of pretreatment . Patients in the highest quartile of IPA had less residual ST segment deviation 1 h post-PCI ( p value for trend : p=0.001 , 0.004 , 0.001 , 0.002 respectively ) . There was a significant relationship between PFA-100 ( both cartridges ) and major adverse cardiovascular events ( MACE , p=0.028 , p=0.035 ) and early thrombosis ( p=0.009 , p=0.007 ) . Conclusions 60 min of prehospital initiated antiplatelet treatment including high-dose tirofiban result ed in higher levels of IPA compared to pretreatment with acetylsalicylic acid and high-dose clopidogrel alone , even after longer pretreatment times . Levels of IPA were significantly related to ST resolution and MACE , including stent thrombosis . This sub study confirms the main findings of the On-TIME2 trial that clopidogrel alone is suboptimal , even at high dose and administered well in advance of primary PCI
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 .