Understanding PFOs and Their Role in Stroke Risk: Advocacy and Awareness

Every year, thousands of young and otherwise healthy individuals suffer from cryptogenic strokes with no clear identifiable cause. Despite its prevalence, public awareness about PFOs and their potential role in stroke risk remains low.

This article explores what PFOs are, how they contribute to stroke risk, what treatment options are available, and how both public and professional advocacy can improve outcomes through earlier diagnosis and better care.

What is a PFO?

During fetal development, a small opening called the foramen ovale exists between the right and left atria of the heart. This opening is crucial before birth, allowing blood to bypass the non-functioning fetal lungs. Typically, the foramen ovale closes shortly after birth when the newborn's lungs take over oxygen exchange.

However, in about 1 in 4 people, this flap-like opening fails to fully close, resulting in a patent foramen ovale (PFO). In most cases, this small hole causes no symptoms and remains undetected for life. But in some individuals, especially those who’ve had unexplained strokes or transient ischemic attacks (TIAs), a PFO may become clinically significant.

When a PFO is present, it can provide a potential route for a blood clot or air bubble to pass from the right side of the heart to the left, bypassing the lungs, which would normally filter such particles and then enter the brain circulation, possibly leading to a stroke. This is known as a paradoxical embolism.

Who Is Most at Risk?

PFO-related strokes are most common in younger patients under 60 years of age with no other identifiable cause of stroke. Additional risk factors include:

• A large PFO or the presence of an atrial septal aneurysm

• A personal or family history of deep vein thrombosis (DVT)

• Migraines with aura

• Use of hormonal contraceptives in women

• Frequent, unexplained TIAs (mini-strokes)

Diagnosing a PFO

Since PFOs often do not produce symptoms, they are usually discovered only after a stroke or TIA. Diagnosis involves specialized heart imaging, such as:

Transesophageal echocardiography (TEE): A probe inserted through the esophagus provides a clear view of the heart’s internal structures.

Transthoracic echocardiography (TTE): A surface ultrasound, less invasive but less sensitive.

Bubble study: Saline mixed with microbubbles is injected into a vein. If bubbles appear in the left atrium, it confirms a right-to-left shunt, suggesting a PFO.

TEE with a bubble study is currently considered the gold standard for PFO detection.

Treatment Options

1. Medical Management

Anti-platelet therapy: e.g., Aspirin

Anticoagulants: e.g., Warfarin, Apixaban (for patients with clotting disorders)

This is usually the first-line approach for patients who are not candidates for PFO closure or who prefer conservative management.

2. PFO Closure:

A minimally invasive catheter-based procedure is used to insert a closure device into the heart to seal the opening. Clinical trials such as RESPECT, CLOSE, and REDUCE have shown that PFO closure significantly reduces the risk of recurrent strokes in patients under 60 with prior cryptogenic stroke.

Most patients go home the same day or after a short overnight stay. The risks are low, and long-term outcomes are generally excellent.

Advocacy and Awareness: Closing the Gap

Despite increasing research around PFOs and their connection to stroke, the reality is that advocacy and provider awareness still lag behind the data. Many young stroke patients leave the hospital without ever hearing the term “PFO.” This is a failure not just of public health outreach but of the medical system itself.

The Current Problem:

• PFOs are underdiagnosed, especially in emergency settings or smaller hospitals.

• Post-stroke evaluations often miss or delay PFO screening.

• Primary care physicians may overlook TIA or unexplained migraines.

• Insurance barriers prevent some patients from getting closure procedures, even when indicated.

What Medical Providers Can Do Better:

1. Think PFO Early in Young Stroke Patients

Any ischemic stroke in a patient under 60 with no apparent cause should raise suspicion for PFO. Providers should ensure appropriate imaging is performed before discharging or labeling a stroke as “cryptogenic.”

2. Improve Interdisciplinary Communication

Stroke care should involve neurologists, cardiologists, and hematologists in a collaborative framework to streamline diagnosis, optimize treatment, and avoid delays in closure procedures.

3. Educate Patients

Patients must be told what a PFO is, what it means for their health, and how it may affect future stroke risk. Educational handouts, visuals, and follow-up plans should be routine parts of discharge after a stroke or TIA.

4. Push for Policy and Insurance Reform

Medical leaders should advocate for improved insurance coverage of diagnostic bubble studies, specialist referrals, and PFO closure in appropriate patients.

Professional societies should also include PFO evaluation in their stroke care guidelines.

5. Normalize Screening in High-Risk Populations

Patients with migraines with aura, frequent unexplained neurologic symptoms, or hyper-coagulable disorders deserve early evaluation. PCPs should feel empowered to refer to cardiology without needing a neurologic event to justify it.

The Bottom Line

PFOs are silent, but their impact can be devastating. As we work to improve stroke prevention strategies, it is essential that both the medical community and the public are better informed.

What Patients Can Do Better:

1. Know the Signs of Stroke and TIA

Even in young people, strokes can happen and PFOs are a hidden culprit. Patients should seek immediate care if they experience:

1. Sudden numbness or weakness on one side

2. Slurred speech or trouble understanding

3. Sudden vision loss or double vision

4. Loss of balance or coordination

5. Severe headache with no known cause

Even brief symptoms that resolve quickly may signal a transient ischemic attack (TIA) and deserve urgent medical attention.

2. Ask the Right Questions

If you’ve experienced a stroke or unexplained neurological symptoms and your doctors haven’t mentioned PFOs, ask them directly:

• “Could this be related to a PFO?”

• “Do I need a bubble study or TEE to evaluate for heart-related causes?”

• “Should I see a cardiologist for further evaluation?”

Asking questions is part of being informed.

3. Follow Through on Testing

If a provider recommends follow-up testing like a TEE or a referral to a cardiologist, make it a priority. Many patients delay or skip appointments once their symptoms improve, but this can lead to missed diagnoses and recurrent strokes.

4. Know Your Medical History

Family history of stroke, clotting disorders, or congenital heart defects should be shared with your healthcare provider. If you’ve ever had unexplained shortness of breath, migraines with aura, or DVT, those details could point toward a PFO.

5. Push for Second Opinions When Needed

If you feel your concerns are dismissed or your symptoms are not being thoroughly investigated, don’t be afraid to seek a second opinion.

Improving outcomes starts with awareness, followed by action. Let’s make PFO-related strokes preventable!