Can Patent Foramen Ovales Cause Problems?

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Patient Presentation
A 4-day-old male came to clinic for his routine followup appointment after discharge from the hospital after birth. The past medical history was a 39 4/7 week male born to a 28 year old G2P2 female without significant medical history. The boy had an echocardiogram after birth because of a potential murmur heard which showed a patent foramen ovale (PFO) and the murmur was thought to be physiologic.

The pertinent physical exam revealed that all birth growth parameters were around the 50% and that at the visit the weight was down 3.6% from birth weight. He had normal vital signs and normal S1 and S2 without murmurs. His upper and lower extremity pulses were also strong and symmetric.

The diagnosis of a healthy male was made. His parents were re-assured by the normal physical examination and normal echocardiogram, but were still worried about the PFO. The pediatrician discussed the natural history of PFOs, noting that some people live their entire lives with one and have no problems. “I expect that he will be just fine. There is always a small chance that he could have a problem but that could even be years in the future. There’s nothing to do now other than to enjoy him and his first days as part of your family,” reassured the pediatrician. The patient’s clinical course found that he continued to be asymptomatic at 18 months of age.

Discussion
During fetal development, the heart primum and secundum septa grow and overlap leaving a small but important channel between the two atria. The foramen ovale is a flap valve moving blood from the right atrium into the left atrium directly and bypassing the high pressure pulmonary system. After birth and breathing air, the neonate’s lungs open up and the pulmonary vascular resistance decreases. The left atrium now has a relatively higher pressure than the right atria, and therefore pressure on the flap valve closes the foramen ovale. Usually within 6-12 months, the fusion of the primum and secundum of the flap valve is complete.

However, this normal change in anatomy and physiology does not occur in a significant number of people (20-34%, and decreases with time with 34% at 30 years and 20% at 80 years) and this situation is called a patent foramen ovale (PFO). Note that a PFO is an abnormality of the atrial septum but is not considered an atrial septal defect (ASD) which results from abnormal development of the atrial septum tissues. ASDs occur in about 1.6/1,000 live births, and are usually diagnosed because of cyanosis, exercise intolerance or a continuous murmur at the left upper sternal border with fixed splitting of S2. The continuous left-to-right shunting can cause volume overload and heart failure. It can also lead to emboli.

PFOs are different than ASDs. They are much more common as noted, generally do not have a murmur, and usually do not cause any problems as the flap valve remains functionally closed. There can be right-to-left shunting across the PFO when transient right atrial pressure exceeds left atrial pressure such as during straining/Valsalva, sneezing or coughing. Usually PFOs are noted only incidentally and do not need treatment. They can also be identified during evaluation for a paradoxical embolism event.

Learning Point
As noted, PFOs can continue to close over years, and usually don’t cause problems. Still PFOs can cause problems for some individuals. In adults, cryptogenic stroke is a current indication for treatment of an identified PFO. Adults with a cryotogenic stroke are more likely to have a PFO (up to 40-50%), and a 2017 New England Journal of Medicine study found that interventional closure of adult PFO decreased recurrent ischemic strokes. Other reasons for adult PFO closure are systemic embolization (e.g. emboli to heart, gut, limbs, etc.), migraine with aura, decompression sickness and platypnea-orthodeoxia syndrome. In pediatrics, most of these indications are rare and therefore less data is available for developing standard indications and guidelines. One study of 10 years of surgical PFO treatment across France showed 41 procedures on children with a mean age of 14.9 years. Occlusion rates were all high at end of the procedure (56.8%), at 1 year (68.6%) and at last follow-up (92.3% with timing 37-5137 days). They had no cases of recurrent stroke (medial followup of 568 days) and no delayed complications.

Questions for Further Discussion
1. What are indications for an echocardiogram?
2. How can heart failure cause arrhythmias?
3. What are most common cyanotic congenital heart defects? A review can be found here
4. What are the most common acyanotic congenital heart defects? A review can be found here

Related Cases

To Learn More
To view pediatric review articles on this topic from the past year check PubMed.

Evidence-based medicine information on this topic can be found at SearchingPediatrics.com and the Cochrane Database of Systematic Reviews.

Information prescriptions for patients can be found at MedlinePlus for this topic: Congenital Heart Defect

To view current news articles on this topic check Google News.

To view images related to this topic check Google Images.

To view videos related to this topic check YouTube Videos.

Saver JL, Carroll JD, Thaler DE, et al. Long-Term Outcomes of Patent Foramen Ovale Closure or Medical Therapy after Stroke. N Engl J Med. 2017;377(11):1022-1032. doi:10.1056/NEJMoa1610057

Giblett JP, Williams LK, Kyranis S, Shapiro LM, Calvert PA. Patent Foramen Ovale Closure: State of the Art. Interv Cardiol Rev. 2020;15:e15. doi:10.15420/icr.2019.27

Miton N, Godart F, Milani G, et al. Patent foramen ovale closure in children without cardiopathy: Child-PFO study. Arch Cardiovasc Dis. 2020;113(8-9):513-524. doi:10.1016/j.acvd.2020.03.021

Cheng T, Gonzalez JB, Testai FD. Advances and ongoing controversies in PFO closure and cryptogenic stroke. Handb Clin Neurol. 2021;177:43-56. doi:10.1016/B978-0-12-819814-8.00009-3

Author
Donna M. D’Alessandro, MD
Professor of Pediatrics, University of Iowa

Published