Personalized antiplatelet treatment improves outcome after PCI

August 28, 2012

Personalized antiplatelet treatment leads to better outcomes than standard antiplatelet treatment in patients undergoing coronary stent implantation, according to results from the MADONNA study presented at ESC Congress 2012.

The findings were presented by Dr Jolanta Siller-Matula from Medical University of Vienna.

Standard antiplatelet treatment in patients undergoing percutaneous coronary intervention (PCI) consists of a dual with aspirin and an ADP receptor inhibitor such as clopidogrel.

But measurements of aggregation in clopidogrel treated patients indicate that one patient in four is a non-responder to the drug. Such non-responsiveness is attributed to clopidogrel's extensive hepatic metabolism, polymorphisms of metabolising enzymes and drug-drug interactions, with additional contributions coming from clinical variables such as diabetes, , acute coronary syndrome, and . Multiple studies have demonstrated a clear association between non-responsiveness to clopidogrel and adverse clinical events. The strongest relationship was found between poor clopidogrel response and short term events, particularly stent thrombosis.

Personalized antiplatelet treatment involves choosing a therapy based on the results of platelet function testing, a measurement which shows how effective an antiplatelet drug such as clopidogrel is at inhibiting platelet aggregation. Non-responders to the drug can be given a higher dose of clopidogrel or an alternate antiplatelet therapy such as the more potent platelet inhibitors prasugrel or ticagrelor. Personalized antiplatelet treatment only in clopidogrel non-responders would be a reaching two goals: increase of clinical efficacy only in patients who are at increased risk for ischemic events without exposing patients with a proper clopidogrel response to bleedings with use of very potent platelet antagonists.

In the MADONNA study (Multiple electrode Aggregometry in patients receiving Dual antiplatelet therapy tO guide treatmeNt with Novel platelet Antagonists), Austrian investigators led by Dr Jolanta Siller-Matula from the Medical University of Vienna and Professor Günter Christ from Kaiser Franz Josef Hospital in Vienna, investigated whether individualized treatment with platelet inhibitors according to the results of whole blood aggregometry improves clinical outcomes in patients undergoing percutaneous .

A total of 798 patients underwent platelet testing with whole blood aggregometry using the multiple electrode aggregometry (MEA) technique, which allowed patients to be classified as clopidogrel responders or non-responders. Patients were then allocated to the guided group or the non-guided group. In the guided group (n=403) clopidogrel non-responders (26%) received up to four loading doses of clopidogrel or after prasugrel became available, the more potent platelet inhibitor prasugrel. In the non-guided group (n=395) clopidogrel non-responders (25%) were further treated with the standard treatment consisting of clopidogrel and aspirin.

Results showed that patients in the non-guided group were at a 7.9-fold higher risk to develop stent thrombosis compared to the patients in the guided group (1.9% versus 0.2%; p=0.027). Furthermore occurred in 0% of patients in the guided group versus 2.5% in the non-guided group (p=0.001). There were no differences between the two groups in the rates of cardiac death or major bleeding.

"Introducing testing into clinical practice might be feasible: it involves a blood sample and takes ten minutes to get a result," said Dr Siller-Matula, first author of the study. "Providing individualized treatment based on the results of MEA instead of using novel antiplatelet drugs in each patient would save costs of drug therapy of about €410 per patient each year. As individualized antiplatelet therapy seems to be cost-effective, it might be of interest to health authorities."

"Physicians would never adjust doses of antihypertensive drugs without knowing blood pressures; statins, without knowing cholesterol levels; or antidiabetic drugs without knowing the HbA1C levels," she added. "So why are we still treating our with platelet inhibitors without being aware of levels of platelet inhibition?"

Explore further: Antiplatelets: 1 person, 1 dose?

Related Stories

Antiplatelets: 1 person, 1 dose?

April 14, 2011
An international consortium of scientists, including major contributions from the Montreal Heart Institute, demonstrates that the "one-size fits all" strategy of uniformly doubling the dose of an antiplatelet drug, clopidogrel, ...

Results of the TRIGGER-PCI trial reported at TCT 2011

November 9, 2011
A clinical trial comparing prasugrel to clopidogrel for patients with high on-clopidogrel platelet reactivity (HCPR) following percutaneous coronary intervention (PCI) was ended early due to relatively few occurrences of ...

30-day results of ADAPT-DES registry reported at TCT 2011

November 9, 2011
The relationship of platelet responsiveness to antiplatelet medications; and, the correlation of poor response, and overall platelet aggregation while on dual antiplatelet therapy to the risk of drug-eluting stent thrombosis ...

Recommended for you

How genes and environment interact to raise risk of congenital heart defects

October 19, 2017
Infants of mothers with diabetes have a three- to five-fold increased risk of congenital heart defects. Such developmental defects are likely caused by a combination of genetic and environmental factors. However, the molecular ...

Mouse studies shed light on how protein controls heart failure

October 18, 2017
A new study on two specially bred strains of mice has illuminated how abnormal addition of the chemical phosphate to a specific heart muscle protein may sabotage the way the protein behaves in a cell, and may damage the way ...

Newborns with trisomy 13 or 18 benefit from heart surgery, study finds

October 18, 2017
Heart surgery significantly decreases in-hospital mortality among infants with either of two genetic disorders that cause severe physical and intellectual disabilities, according to a new study by a researcher at the Stanford ...

Saving hearts after heart attacks: Overexpression of a gene enhances repair of dead muscle

October 17, 2017
University of Alabama at Birmingham biomedical engineers report a significant advance in efforts to repair a damaged heart after a heart attack, using grafted heart-muscle cells to create a repair patch. The key was overexpressing ...

Physically active white men at high risk for plaque buildup in arteries

October 17, 2017
White men who exercise at high levels are 86 percent more likely than people who exercise at low levels to experience a buildup of plaque in the heart arteries by middle age, a new study suggests.

High blood pressure linked to common heart valve disorder

October 17, 2017
For the first time, a strong link has been established between high blood pressure and the most common heart valve disorder in high-income countries, by new research from The George Institute for Global Health at the University ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.