Timing of 2 antiplatelet medications following stent placement

This study looked at giving 3 months or 12 months of dual antiplatelet medications following placement of a stent for patients with heart disease. It found that a shorter time on a dual regimen may lead to better outcomes than a longer period.

Coronary artery disease (CAD) occurs when the arteries leading to the heart become clogged with plaque. CAD increases the risk of a heart attack. One treatment option for CAD is an angioplasty and stent placing. This procedure threads a device into the artery and uses a small balloon to stretch the area which is narrowed. Then a stent, or tube, is left in the artery to keep it open.

In some cases, the immune system perceives the stent as a foreign body and causes inflammation. This can lead to the artery narrowing again (restenosis). To prevent this, some stents now contain a medication which reduces immune system activity. These drug-eluting stents have lower rates of the artery re-narrowing. However, they may also have higher rates of blood clots. Orsiro stents are an example of this type and contain the medication sirolimus (Rapamune).

Following a stent placement, patients take antiplatelet medications to prevent the blood from clotting. The most common treatment is dual antiplatelet therapy (DAPT). DAPT uses a P2Y12 inhibitor such as clopidogrel (Plavix), together with aspirin. However, it is not clear what is the best duration of DAPT for drug-containing stents.

This study included 972 patients who received Orsiro stents. Half of the patients were randomly assigned to receive DAPT for 12 months following the surgery. The other half received DAPT for 3 months, followed by 9 months of a P2Y12 inhibitor alone.

Significantly fewer patients in the 3-month group experienced a stent failure compared to the 12 months DAPT group (1.7% vs. 2.9%). Stent failure included a heart attack, death related to heart function, or additional surgery to open the artery. The 3-month DAPT regimen may particularly reduce stent failure for patients with diabetes (1.0% vs. 4.7%)

There were no stent-related blood clots in either group. There were similar rates of side effects in both groups.

This study found that a 3-month DAPT regimen may lead to less failure of Orsiro stents than the 12-month regimen for patients with CAD.

This study received funding from the Korean branch of Biotronik, the manufacturer of Orsiro stents.