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 .
Comparison of platelet function tests in predicting clinical outcome in patients undergoing coronary stent implantation.
Context High on-treatment platelet reactivity is associated with atherothrombotic events following coronary stent implantation . Objective To evaluate the capability of multiple platelet function tests to predict clinical outcome . Design , Setting , and Patients Prospect i ve , observational , single-center cohort study of 1069 consecutive patients taking clopidogrel undergoing elective coronary stent implantation between December 2005 and December 2007 . On-treatment platelet reactivity was measured in parallel by light transmittance aggregometry , Verify Now P2Y12 and Platelet works assays , and the IMPACT-R and the platelet function analysis system ( PFA-100 ) ( with the Dade PFA collagen/adenosine diphosphate ( ADP ) cartridge and Innovance PFA P2Y ) . Cutoff values for high on-treatment platelet reactivity were established by receiver operating characteristic curve ( ROC ) analysis . Main Outcome Measurement The primary end point was defined as a composite of all-cause death , nonfatal acute myocardial infa rct ion , stent thrombosis , and ischemic stroke . The primary safety end point included TIMI ( Thrombolysis In Myocardial Infa rct ion ) criteria major and minor bleeding . Results Kaplan-Meier analysis demonstrated that at 1-year follow-up , the primary end point occurred more frequently in patients with high on-treatment platelet reactivity when assessed by light transmittance aggregometry ( 52 [ 11.7 % ; 95 % confidence interval { CI } , 8.9%-15.0 % ] vs 36 [ 6.0%;95%CI , 4.2%-8.2 % ] P.001 ; n=1049),Verify Now ( 54 [ 13.3 % ; 95 % CI , 10.2%-17.0 % ] vs 37 [ 5.7 % ; 95 % CI , 4.1%-7.8%]P.001 ; n=1052 ) , Platelet works ( 33 [ 12.6 % ; 95 % CI , 8.8%-17.2 % ] vs 21 [ 6.1%;95 % CI , 3.8%-9.2 % ] P=.005 ; n=606 ) , and Innovance PFA P2Y ( 18 [ 12.2 % ; 95%CI ; 7.4%-18.6 % ] vs 28 [ 6.3 % ; 95 % CI , 4.3%-8.9 % ] P=.02 ; n=588 ) . ROC-curve analysis demonstrated that light transmittance aggregometry ( area under the curve[AUC ] , 0.63 ; 95 % CI , 0.58 - 0.68 ) , Verify Now ( AUC , 0.62 ; 95 % CI , 0.57 - 0.67 ) , and Platelet works ( AUC , 0.61 ; 95 % CI , 0.53 - 0.69 ) had modest ability to discriminate between patients with and without primary end point at 1-year follow-up . The IMPACT-R(n=905 ) and the Siemens PFA Collagen/ADP ( n=812 ) were unable to discriminate between patients with and without the primary end point at 1-year follow-up ( all AUCs included 0.50 in the CI ) . None of the tests identified patients at risk for bleeding . Conclusions Of the platelet function tests assessed , light transmittance aggregometry , Verify Now , Platelet works , and Innovance PFA P2Y were significantly associated with the primary end point . However , the predictive accuracy of these 4 tests was only modest . None of the tests provided accurate prognostic information to identify patients at higher risk of bleeding following stent implantation . Trial Registration clinical trials.gov Identifier : NCT00352014 [ corrected ]
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 .