• May 2021

    AFib and Stroke: Understanding the connection to help prevention

An estimated 3 million individuals in the U.S. live with a condition called atrial fibrillation, or AFib, with some estimates projecting that number being closer to 6 million when taking unknown and undiagnosed cases into account.

AFib is commonly associated with an irregular heartbeat, however the condition carries many other symptoms and risks factors that few realize.

Craig Delaughter, MD and Anita Krueger, MD are involved in a variety of both clinical and research-focused efforts aimed at improving quality of life for patients with AFib. The two sat down with Scrubbing In to talk about some of the little known details for this common condition and efforts within research aimed at addressing more management options for patients living with AFib.

AFib is a condition many people think only affects a certain age group, is that accurate?

Delaughter: AFib is more common in the elderly, but a fact that may surprise many, is that it can happen to individuals as young as teenagers. This is often the case in patients who have conditions such as sleep apnea, hypertension, diabetes, valvular heart disease, as well as increased alcohol use.

How do people “experience” AFib?

Krueger: Patients with AFib can often experience their symptoms differently, however a fluttering, irregular heart rhythm, shortness of breath, chest pain or lightheadedness are the most common signs.

Delaughter: In addition to the examples Dr. Krueger noted, AFib also causes other things to happen in the body. AFib can cause the heart rate to be fast for long periods of time. This can weaken the heart in a process called tachycardia induced cardiomyopathy. Additionally, because AFib reduces the velocity of blood in a part of the heart called the left atrial appendage (LAA), this increases the risk of blood clot formation. If such a clot forms and makes its way into the bloodstream, it can cause a stroke or damage other organs. As a result, AFib patients live with a heightened stroke risk.

Does that make stroke risk another issue that AFib patients have to also learn to manage?

Krueger: Unfortunately, yes. But we have options out there – and others being studied rigorously in clinical trials – to help make that management easier. The goal is always to try and take the risk or condition off the table completely, but until that day, we focus on all the tools we have available to help our patients manage while keeping a good quality of life.

What are these management options?

Delaughter: As Dr. Krueger mentioned, there are standard options and we are involved in research aimed at expanding our knowledge of options depending on different patient needs and preferences.

Currently, to reduce stroke risk for AFib patients, most are prescribed anticoagulation, or blood thinning medicine that makes it harder for the blood to clot. For patients who cannot take blood thinners, there is an option where we place a “plug” (also known as an occluder) in the LAA so no clots can form within it. This device is a mechanical alternative to long-term blood thinning medication.

Krueger: The plug is implanted by threading the LAA occluder through the groin.  Another option is a clip that goes across the base of the LAA using a minimally-invasive surgical approach which involves three small incisions between the ribs.

What are some of the reasons people opt against taking a blood thinner?

Delaughter: There are a number of reasons, actually. Some patients’ bodies cannot tolerate blood thinners. There are individuals that have other health issues like cancer or bone marrow problems, or they have health concerns that come with higher bleeding and fall risks, like dementia. When you’re on blood thinners, you bleed longer and more extensively, so these factors become a major point of consideration. Additionally, some patients may not be able to afford the medication or may simply want to reduce the number of medicines they’re taking every day – these are all valid reasons, and we want to think about how we can get folks the care they need in the most manageable ways possible.

Is this where some of your research involvement comes in?

Krueger: Yes. The LAA occlusion implant has already been approved for patients who cannot tolerate blood thinners due to other health issues, like the examples we mentioned earlier. There are clinical trials that we are involved in that seek to understand what’s safe for patients who do not want to take blood thinners for the non-health reasons we described.

How do these trials work?

Delaughter: Each study carries different parameters. One example is a trial designed to determine if the LAA occlusion implant provides the same stroke protection as blood thinning medication in patients without underlying health issues. To make a fair (and unbiased) comparison, patients who meet the trials enrollment criteria are randomly assigned to either the LAA occlusion implant procedure or blood thinning medication.

Krueger: It’s a 50/50 comparison of blood thinners vs LAA occlusion implant for AFib patients who are currently expected to take blood thinning medication. Participants are assigned at random to keep things as balanced and unbiased as possible. If randomized to the LAA occlusion implant, participants would spend one day at the hospital for the procedure, 4-6 weeks later, they would come back for an ultrasound test called a TEE to check that the implant is plugged the LAA properly.

So, some of these trials test things that aren’t new?

Delaughter: Exactly. Like many of the trials in which we are involved, this study looks to see if a procedure that’s been approved for one use in certain populations provides the same level of effectiveness compared to the current standard, in this case taking blood thinners, in other populations.

Krueger: There’s a lot of information related to AFib out there, particularly when you think about what’s available to manage AFib and associated risk factors, and what’s in development. It’s important that patients and their family members feel comfortable asking their doctors about these options and make that type of conversation part of their ongoing healthcare experience. The rate of innovation in medicine can be rapid and changes can happen at any time, so staying informed and making your care team a part of that information gathering process is always a plus.