CardioExchange Archive

According to current recommendations, dual antiplatelet therapy (DAPT) should be administered for a minimum of 12 months after drug eluting stent (DES) implantation to prevent late stent thrombosis. However, prolonged DAPT is associated with higher bleeding rates when compared with treatment with aspirin alone.

According to two recently published studies, temporary discontinuation of antiplatelet therapy is safe, and DAPT needs to be given for only 3 months with the newer DES. Ferreira-González and colleagues report that discontinuation of antiplatelet therapy for a few days (median, 7 days) after the first month of DES implantation is safe in terms of major cardiac events. In patients who received the second generation Endeavor zotarolimus-eluting stent (Medtronic, Santa Rosa, California) in the RESET* Trial, 3 months of DAPT was noninferior to standard therapy (12 months of DAPT with other DES) with respect to the composite endpoint of cardiovascular death, MI, stent thrombosis, bleeding, and target lesion or vessel revascularization at 1 year.

What does our resident expert on the topic, Dr. Deepak Bhatt, think about these findings?

1. Your patient had a DES placed 3 months ago and now needs an elective knee replacement. Do you advise her to wait until she’s completed 12 months of DAPT or to temporarily discontinue her antiplatelet therapy to have the surgery now?

This is a very common and challenging scenario in cardiovascular medicine. I wish there were an easy or standard answer, but there is not. First of all, if I had implanted a stent 3 months ago, I would have asked if there were any potential surgeries coming up in the next several months. Let us assume that she did not feel she needed surgery 3 months ago, but now she feels she does. I would still try to stretch out the waiting period to 12 months of dual antiplatelet therapy if at all possible, but would likely settle for 6 months if her knee pain was severe and could not be controlled with oral medications or knee injections. But it depends… If she had come in with a large STEMI, I would push harder for the 12 months. If it were an LAD/diagonal bifurcation stent (and I try to avoid placing bifurcation stents unless really necessary), I might push harder for 12 months. So, the clinical indication and the anatomy both matter to me. And regardless of when she decides to have the surgery, I would insist on aspirin being continued uninterrupted.

2. If patients receive one of the newer stents, is it time to loosen up on DAPT duration?

This is a bit of a weak answer, but I would say we need more data. I really want the answer to be yes, as do almost all cardiologists. But we need to wait for the results of large randomized clinical trials such as DAPT, which is testing durations of dual antiplatelet therapy longer than 12 months, as well as a number of smaller trials that are testing shorter durations of DAPT. The dilemma, of course, is that stent thrombosis is an infrequent event, whereas bleeding and the need for surgery are both relatively common events. Therefore, only large trials and meta-analyses of smaller trials may provide insight into the “right” answer to this question. Until such a time, I would stick with the guideline recommendations and continue for 12 months, assuming that the patient is not at high risk for bleeding. But if the patient did run into trouble with bleeding — including frequent “nuisance” bleeding — or needed surgery that ideally would not wait, I would not be overly dogmatic about the 12 months with the newer-generation DES and would allow good clinical sense to prevail.