Most people with atrial fibrillation do not need bridging when warfarin is temporarily stopped for a procedure. Both the American College of Chest Physicians and the ACC/AHA guidelines now recommend against routine heparin bridging for AFib patients, based on strong evidence that it increases bleeding risk without meaningfully reducing stroke risk.
What Bridging Means and Why It Exists
Warfarin takes several days to wear off and several more days to reach full effect again. That creates a window around any surgery or procedure where your blood isn’t adequately thinned. Bridging was designed to fill that gap: you’d stop warfarin about five days before the procedure, then inject a fast-acting blood thinner (usually a low-molecular-weight heparin) in the days leading up to and after surgery. The idea was to keep you protected from stroke during the transition.
For years, this was standard practice. But as more data came in, it became clear that for most AFib patients, bridging causes more harm than it prevents.
What the BRIDGE Trial Found
The landmark study that changed practice was the BRIDGE trial, published in the New England Journal of Medicine. It enrolled over 1,800 AFib patients who needed to stop warfarin for an elective procedure. Half received bridging with heparin injections, and half received no bridging at all.
The results were striking. Stroke and blood clot rates were nearly identical in both groups: 0.4% without bridging versus 0.3% with bridging. But major bleeding told a very different story: 1.3% in the no-bridging group compared to 3.2% in the bridging group. Skipping the bridge cut major bleeding risk by more than half, with no trade-off in stroke protection. The average participant had a moderate stroke risk score, and patients with scores ranging from low to high were included.
What Current Guidelines Recommend
The 2022 American College of Chest Physicians guideline made one of its only two strong recommendations in the entire perioperative anticoagulation section: do not use heparin bridging in patients with atrial fibrillation. That’s the strongest language a medical guideline uses, reflecting high confidence in the evidence.
The 2023 ACC/AHA atrial fibrillation guideline echoes this, noting that observational studies consistently show increased bleeding without any difference in clot risk when bridging is used. A meta-analysis of six studies found that AFib patients who skipped bridging had a thromboembolic event rate of just 0.6%.
Who Might Still Need Bridging
There are exceptions. If you have a mechanical heart valve, the calculus is different because these valves carry a much higher clot risk than AFib alone. Patients who’ve had a recent stroke or transient ischemic attack (within the past few months) may also fall into a higher-risk category where bridging is considered. These situations weren’t well represented in the major trials, so guidelines recommend individualized decisions made between you and your care team rather than a blanket no-bridging approach.
The key distinction is between AFib on its own and AFib combined with other high-risk features. For the vast majority of people whose only reason for warfarin is atrial fibrillation, skipping the bridge is the safer choice.
Some Procedures Don’t Require Stopping Warfarin at All
For low-bleeding-risk procedures, the question of bridging doesn’t even come up because warfarin can simply be continued. Dental work is the most common example. Studies show that continuing warfarin at a therapeutic level during dental extractions and other dental procedures is safe, and that bridging in these situations actually leads to more bleeding, not less. Cataract surgery and certain skin procedures also typically fall into this low-risk category where interruption isn’t necessary.
What the Timeline Looks Like When Warfarin Is Stopped
When you do need to pause warfarin for a higher-risk procedure, the typical approach is straightforward. You stop warfarin about five days before surgery, giving your clotting function time to normalize. Your care team will usually check your INR (a measure of how thinned your blood is) shortly before the procedure to confirm it’s in a safe range.
After surgery, warfarin is typically restarted the day after the procedure, since it takes several days to build back up to its full effect. For patients considered high risk, a fast-acting blood thinner can be restarted about 24 hours after surgery once it’s clear there’s no active bleeding. If there’s concern about postoperative bleeding, intravenous heparin is sometimes preferred in that first 24-hour window because it can be turned off quickly if problems arise.
Why This Matters if You’re on Warfarin
If you’re taking warfarin for AFib and have an upcoming procedure, the most likely scenario is that your doctor will simply stop the warfarin a few days beforehand and restart it afterward, with no bridging injections needed. This is a significant shift from how things were done a decade ago, so if you’ve had bridging in the past, don’t be surprised if the recommendation is different now.
Your stroke risk score (called CHA2DS2-VASc) plays a role in the conversation. This score adds points for factors like age, high blood pressure, diabetes, prior stroke, heart failure, and vascular disease. Even among patients with moderate scores, the evidence strongly favors skipping bridging. The score matters more for deciding whether you need to be on anticoagulation at all than for deciding whether to bridge around a procedure.
It’s also worth noting that if you’re on a newer blood thinner (a direct oral anticoagulant like apixaban or rivarelbaban), bridging is essentially never used. These medications wear off and kick back in much faster than warfarin, so the gap that bridging was meant to fill doesn’t really exist.