New Decision Tool Helps Refine Blood Thinner Use in Stent Patients
DAPT score helps weigh the risks and benefits of continued dual antiplatelet therapy after stent implantation.
A new risk score helps determine how long patients should continue aggressive blood thinner treatment after receiving a heart stent, according to a study published in the Journal of the American College of Cardiology.
Led by researchers at Brigham and Women’s Hospital, this study tested a decision tool that weighs the risks and benefits of dual blood thinner use in stent patients.
Dual antiplatelet therapy (DAPT), which includes both aspirin and a second blood thinner, is recommended for nearly all patients after receiving a stent. This drug regimen helps prevent clots from forming around the device and reduces risk for future heart events. But since blood thinners increase risk of bleeding, some patients stop therapy earlier than others to prevent complications. Exactly how long patients should continue dual blood thinners after stent implantation is unclear.
That’s why researchers created the DAPT score, which calculates cardiovascular risk based on factors like age and history of heart events. DAPT scores range from -2 to 10, with higher scores indicating greater cardiovascular risk. The greater the cardiovascular risk, the more likely a patient is to benefit from continued blood thinner therapy. But how well does the DAPT score work?
To assess its value, researchers applied their risk score to the DAPT study, which tested dual blood thinner use in more than 25,600 patients receiving stents.
During the study, patients were randomly assigned to dual blood thinner therapy for either one or two and a half years after stent implantation. The results, which were previously published, showed that patients taking dual blood thinner beyond a year had lower heart attack risk but higher bleeding risk than those who stopped aggressive therapy after 12 months.
The good news, however, is that applying the DAPT score helps predict the potential benefits and harm of continued therapy. In patients with a DAPT score of two or more, dual blood thinner use after a year helped minimize risk of bleeding while reducing heart attack risk. On the other hand, patients with a score below two who continued treatment had greater risk of bleeding and lower cardiovascular risk reductions. Authors also note that patients with a history of heart attack tend to benefit most from continued dual blood thinner therapy, since their cardiovascular risk is greater.
Based on findings, the DAPT score may be useful in identifying which patients should continue dual antiplatelet therapy a year after stent implantation. Although dual blood thinners helps reduce risk for future heart events, risk of complications may be too high for some patients. Having an objective measure like the DAPT score may be helpful when it comes to decision making regarding treatment. With more research, experts hope to continue to refine which patients should continue dual antiplatelet therapy to improve outcomes.
Questions for You to Consider
- What is a blood thinner?
- A blood thinner slows down the blood's ability to form clots. This helps prevent clots that can cause life-threatening problems such as stroke, heart attack and pulmonary embolism. These medicines also can keep blood clots from getting bigger. Blood thinner medicines work in different ways to prevent blood clots, but all of them raise the risk of serious bleeding.