Atrial Fibrillation With Low Blood Pressure: What to Know

Medically Reviewed by James Beckerman, MD, FACC on July 11, 2022
Written by WebMD Editorial Contributors
3 min read

Atrial fibrillation, also called AFib, is a complex condition with many causes. Blood pressure problems are just one of the risk factors. But atrial fibrillation itself can lead to changes in blood pressure. Hypotension, or low blood pressure, is something to look out for. Here’s what you need to know.

There are two types of hypotension:

Absolute hypotension. This is when your blood pressure is below 90/60 mm Hg, even when you’re resting.

Orthostatic, or postural, hypotension. This is when your blood pressure drops within 3 minutes of standing up. It has to be at least 20 mm Hg for systolic blood pressure and at least 10 mm Hg for diastolic blood pressure. Systolic blood pressure (the top number) is the pressure of your heart when it’s contracting. Diastolic blood pressure (the bottom number) is the pressure in your arteries between heartbeats.

Anyone can have hypotension. But it doesn’t always cause symptoms, especially if you’re young or active. So it’s hard to know how many people have the condition. Orthostatic hypotension appears to affect older adults more often and is more common with age. Experts estimate 5% of people age 50 have it. If you’re over age 70, that rate rises to 30%.

Yes, but it’s usually the other way around. With atrial fibrillation, the heart beats irregularly. This can affect how well it pumps, triggering low blood pressure.

Orthostatic hypotension in particular may be at the root of atrial fibrillation. Research suggests your risk of having atrial fibrillation rises by 40% when you have orthostatic hypotension.

This type of hypotension has several symptoms, including:

Your symptoms might be mild or brief, but you still need attention. Ongoing hypotension could be a sign of other problems. Tell your doctor if you have any of these symptoms.

If you have atrial fibrillation, the drugs used to treat your condition could trigger hypotension. Beta-blockers help with both rate and rhythm control. These include:

Verapamil, a calcium channel blocker, could also lead to hypotension.

If you have both AFib and pre-excitation (an electrical disorder of the heart), cardiologists don’t recommend verapamil. It may speed up your heart and eventually cause hypotension.

Treatment can bring your blood pressure back up to normal levels. Ask your doctor what to expect in your case, based on how severe your atrial fibrillation is, your overall health, and other things.

If your hypotension is a side effect of your atrial fibrillation medications, talk to your doctor about adjusting your dose or trying another medication. But don’t stop taking your pills.

Sometimes your atrial fibrillation symptoms may suddenly worsen with a heart rate above 120 beats per minute. When this acute, or unstable, atrial fibrillation occurs, one of your symptoms may be hypotension.

Call 911 or go to the nearest emergency room right away. You’ll get medications to slow your heart rate and possibly an anticoagulant to avoid clotting. You may need electrical cardioversion, a procedure to control your heart rhythm. The treatment uses a high-energy electric shock to reset your heart.

In general, the main treatments for hypotension include:

  • Raising your blood volume by getting intravenous fluids, plasma, or blood transfusions
  • Taking medications that make your blood vessels constrict, or narrow
  • Using medications to help your kidneys keep fluid and salt in your body

Yes. It’s important to:

  • Take your meds as instructed.
  • Wear compression socks.
  • Avoid standing up too quickly.
  • Sit down and rest if you feel dizzy or faint.

Always keep an eye out for signs that you need emergency care. Call 911 or go to the nearest emergency room if you:

  • Feel chest pain
  • Pass out or faint
  • Fall and hit your head
  • Injure yourself after passing out

Do the same if you have symptoms of shock. These include: