Most studies indicated that low on-treatment platelet reactivity ( LTPR ) , as measured by several platelet function tests , and the carriage of CYP2C19 * 17 allele were independent risk factors for bleeding .
A bleeding score also proved to be helpful in identifying patients at risk .
Several patient characteristics were also identified as independent predictors of bleeding , such as older age , female sex and renal failure .
Patients with coronary artery disease are usually treated with dual antiplatelet therapy ( DAPT ) after percutaneous coronary intervention .
Patients on DAPT are at risk of both ischaemic and bleeding events .
Although side-lined for a long time , real-life studies have shown that both the incidence and the associated morbidity and mortality of out-of-hospital bleeding are high .
This indicates that prevention of ( post-interventional ) bleeding is as important as prevention of ischaemia .
For this purpose it is crucial to reliably identify patients with a high bleeding risk .
In order to postulate an algorithm , which could help identifying these patients , we performed a systematic review to determine the value of previously proposed prognostic modalities for bleeding .
Platelet reactivity and clinical outcomes after coronary artery implantation of drug-eluting stents (ADAPT-DES): a prospective multicentre registry study
BACKGROUND The relation between platelet reactivity and  stent thrombosis , major bleeding , and other adverse events after coronary artery implantation of drug-eluting stents has been incompletely characterised . We aim ed to determine the relation between platelet reactivity during dual therapy with aspirin and clopidogrel and clinical outcomes after successful coronary drug-eluting stent implantation . METHODS ADAPT-DES was a prospect i ve , multicentre registry of patients successfully treated with one or more drug-eluting stents and given aspirin and clopidogrel at 10 - 15 US and European hospitals . We assessed platelet reactivity in those patients after successful percutaneous coronary intervention using VerifyNow point-of-care assays  , and assigned different cutoffs to define high platelet reactivity . The primary endpoint was definite or probable stent thrombosis ; other endpoints were all-cause mortality , myocardial infa rct ion , and clinical ly relevant bleeding . We did a propensity-adjusted multivariable analysis to determine the relation between platelet reactivity and subsequent adverse events . This study is registered with Clinical Trials.gov , number NCT00638794 . FINDINGS Between Jan 7 , 2008 , and Sept 16 , 2010 , 8665 patients were prospect ively enrolled at 11 sites , of which 8583 were eligible . At 1-year follow-up , stent thrombosis had occurred in 70 ( 0·8 % ) patients , myocardial infa rct ion in 269 ( 3·1 % ) , clinical ly relevant bleeding in 531 ( 6·2 % ) , and death in 161 ( 1·9 % ) patients . High platelet reactivity on  clopidogrel  was strongly related to stent thrombosis ( adjusted HR 2·49 [ 95 % CI 1·43 - 4·31 ] , p=0·001 ) and myocardial infa rct ion ( adjusted HR 1·42 [ 1·09 - 1·86 ] , p=0·01 ) , was inversely related to bleeding ( adjusted HR 0·73 [ 0·61 - 0·89 ] , p=0·002 ) , but was not related to mortality ( adjusted HR 1·20 [ 0·85 - 1·70 ] , p=0·30 ) . High platelet reactivity on aspirin was not significantly associated with stent thrombosis ( adjusted HR 1·46 [ 0·58 - 3·64 ] , p=0·42 ) , myocardial infa rct ion , or death , but was inversely related to bleeding ( adjusted HR 0·65 [ 0·43 - 0·99 ] , p=0·04 ) . INTERPRETATION The findings from this study emphasise the counter-balancing effects of haemorrhagic and ischaemic complications after stent implantation , and suggest that safer drugs or tailored strategies for the use of more potent agents must be developed if the benefits of greater platelet inhibition in patients with cardiovascular disease are to be realised . FUNDING Boston Scientific , Abbott Vascular , Medtronic , Cordis , Biosensors , The Medicines Company , Daiichi-Sankyo , Eli Lilly , Volcano , and Accumetrics
Most studies indicated that low on-treatment platelet reactivity ( LTPR ) , as measured by several platelet function tests , and the carriage of CYP2C19 * 17 allele were independent risk factors for bleeding .
A bleeding score also proved to be helpful in identifying patients at risk .
Several patient characteristics were also identified as independent predictors of bleeding , such as older age , female sex and renal failure .
Patients with coronary artery disease are usually treated with dual antiplatelet therapy ( DAPT ) after percutaneous coronary intervention .
Patients on DAPT are at risk of both ischaemic and bleeding events .
Although side-lined for a long time , real-life studies have shown that both the incidence and the associated morbidity and mortality of out-of-hospital bleeding are high .
This indicates that prevention of ( post-interventional ) bleeding is as important as prevention of ischaemia .
For this purpose it is crucial to reliably identify patients with a high bleeding risk .
In order to postulate an algorithm , which could help identifying these patients , we performed a systematic review to determine the value of previously proposed prognostic modalities for bleeding .