5 Key Questions to Consider

Hi, I’m Margaret Fang. I’m at the University of California, San Francisco, and I am in the Division of Hospital Medicine. I’m also the medical director for the anticoagulation clinic at UCSF.

In this episode of Clot Chronicles, we’re going to talk about periprocedural anticoagulation. So, my approach to periprocedural anticoagulation, which is when you need to stop anticoagulants or manage anticoagulants around the time of an invasive procedure, is a multistep approach.

First, I ask, “do you really need to stop the anticoagulants?” Because for some procedures you don’t—simple dental extractions, for example, some cardiac procedures, such as pacemaker implantation or catheter ablation—you don’t need to stop an anticoagulant for that.

So first, figure out if you need to stop the anticoagulant. The next question I ask is, “what’s the bleeding risk with the procedure?” There are some procedures that have a very high risk of bleeding on anticoagulants. So, for example, if you’re going through major surgery, it’s probably wise to stop the anticoagulant. For a minor procedure, you might need to stop that anticoagulant for a shorter period of time.

The next thing we do is try to figure out what someone’s thrombosis risk is off of anticoagulation. And that really depends on why someone is taking anticoagulants in the first place. The three main indications are atrial fibrillation (Afib), venous thromboembolism (VTE), and mechanical heart valves.

For Afib, I use a stroke risk index, such as the CHA2DS2-VASC score, to figure out someone’s risk of stroke. I also ask whether they’ve had a recent stroke, say in the last month to three months.

For VTE, the risk of developing a recurrent clot really depends on if the patient has had a history of recurrent clots off of anticoagulation, if they have an inherited thrombophilia, a clotting disorder, or if the clot was very recent, such as in the last month or three months.

And then for the final category of mechanical heart valves, it really depends on the type of valve. There are some valves that are very prone to clots, such as mitral valves. And there are ones that have a lower risk for clots, like aortic valves. And it depends on a person’s other risk factors, such as whether they have Afib as well as a mechanical heart valve.

Once you determine whether someone’s at high or low thrombosis risk, the next question is, “what do you do with the anticoagulant?” For someone who is taking warfarin, you have to hold it for a certain number of days so that the warfarin wears off. And typically, for a major surgery, it’s about five days.

For the newer, direct oral anticoagulants, the time that you would hold is shorter. And there’s recent evidence that shows that holding for about one day prior to a low-risk procedure, or two days prior to a higher-risk procedure, is associated with pretty good reversal of anticoagulant effect and pretty good thrombosis and bleeding outcomes after holding.

After you figure out how long to hold your anticoagulant, whether it’s warfarin or a direct oral anticoagulant, the final question is, “does that person need bridging?” Bridging was used much more commonly in the past. It refers to the use of a short-acting anticoagulant, such as heparin or low-molecular-weight heparin, around the time that you’re holding a longer acting oral anticoagulant.

There is more recent evidence that bridging may not be as needed as people used to think. For Afib, there was a large, randomized trial called the BRIDGE study, which showed that bridging didn’t really lead to better outcomes. In fact, it probably caused more bleeding. And so we don’t recommend bridging for the average person with Afib unless they have a very high CHA2DS2-VASc score.

For VTE, there really weren’t any randomized, controlled trials. But in the past year, there was a systematic review that was published that looked at all the observational data comparing bridging to nonbridging in people with VTE, and that showed kind of the same results as the BRIDGE study. They didn’t have much of a difference in preventing recurrent VTE around the time of surgery, but it was associated with a significantly higher risk of bleeding.

So now, for VTE, bridging probably should be reserved only for the very highest risk patients. And for the average person with a history of VTE that’s at low or moderate risk, bridging is probably not necessary.

So, I hope that helps with an approach to the periprocedural management of anticoagulation. First, think about whether the procedure need to be done on anticoagulants or off anticoagulants. Two, figure out the bleeding risk of the procedure. Three, look at the thrombosis risk of the patient, and that relates to why they’re taking anticoagulants in the first place. Figure out how long you should hold an anticoagulant. And for certain select patients, maybe bridging is a reasonable option, but for the majority of patients, bridging is probably not necessary for Afib or VTE.

Thank you so much. I’ve really enjoyed talking to you today.