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 .
Preoperative Aspirin Resistance does not Increase Myocardial Injury during Off-pump Coronary Artery Bypass Surgery
We performed a prospect i ve cohort trial on 220 patients undergoing elective off-pump coronary artery bypass surgery and taking  aspirin to evaluate the effect of aspirin resistance on myocardial injury . The patients were divided into aspirin responders and aspirin non-responders by the value of the aspirin reaction units obtained preoperatively using the VerifyNow ™ Aspirin Assay . The serum levels of troponin I were measured before surgery and 1 , 6 , 24 , 48 and 72 hr after surgery . In-hospital major adverse cardiac and cerebrovascular events , graft occlusion , the postoperative blood loss and reexploration for bleeding were recorded . Of the 220 patients , 181 aspirin responders ( 82.3 % ) and 39 aspirin non-responders ( 17.7 % ) were defined . There were no significant differences in troponin I levels ( ng/mL ) between aspirin responders and aspirin non-responders : preoperative ( 0.04 ± 0.08 vs 0.03 ± 0.06 ; P = 0.56 ) , postoperative 1 hr ( 0.72 ± 0.87 vs 0.86 ± 1.10 ; P = 0.54 ) , 6 hr ( 2.92 ± 8.76 vs 1.50 ± 2.40 ; P = 0.94 ) , 24 hr ( 4.16 ± 13.44 vs 1.25 ± 1.95 ; P = 0.52 ) , 48 hr ( 2.15 ± 7.06 vs 0.65 ± 0.95 ; P = 0.64 ) and 72 hr ( 1.20 ± 4.63 vs 0.38 ± 0.56 ; P = 0.47 ) . Moreover , no significant differences were observed with regard to in-hospital outcomes . In conclusion , preoperative aspirin resistance does not increase myocardial injury in patients undergoing off-pump coronary artery bypass surgery . Postoperative dual antiplatelet therapy might have protected aspirin resistant patients
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 .