Clinical vignettes
Case 1
A 3-month-old infant girl was referred to the cardiac clinic for a systolic heart murmur. She was born at full term with an uncomplicated perinatal period and had done well since birth. An echocardiogram performed during the office visit showed physiological peripheral pulmonary stenosis and a PFO with a trivial left to right shunt. The remainder of the cardiac anatomy and function were normal. The parents were informed of these findings and were reassured that there was no significant heart disease and that the infant did not need further cardiology follow-up. On hearing the term PFO, the mother was concerned as the infant girl’s great grandmother (a septuagenarian), was recently diagnosed with a PFO after a stroke and underwent device closure of the PFO. Per the family’s understanding, the PFO could have caused the stroke and they were told that closing the PFO would prevent future strokes. The paediatric cardiologist now seeing the infant reassured the parents that even though the diagnosis (PFO) was the same, these were two different situations and that there was no need for concern. He further explained to the parents that a PFO is a not unusual finding on echocardiogram in infants and that most of them close with time. He also informed them that a PFO may be present in about 20–25% of the adults without causing harm. The parents were relieved to hear this and the child was discharged from the cardiology clinic.
Case 2
A 14-year-old teenage girl was referred for a second opinion for a PFO. She was previously evaluated by a cardiologist for recurrent episodes of chest pain, some of which occurred during physical exertion. She was a champion swimmer and gold medalist in her school gymnastics team for the past 2 years. The outside evaluation included an echocardiogram which showed a tiny PFO, seen only with colour flow Doppler imaging, with a trivial left to right shunt. The rest of the cardiac anatomy (including coronaries) and function were normal. The prior cardiologist informed the family that the child had a small “hole in the heart” between the two atria. They were also told that the only precaution she had to take was to not do Scuba diving, as there was a risk for stroke. The parents were also informed that there was also a rare risk for stroke during childbirth from amniotic fluid embolism if she still had a PFO when she went into labour during her child-bearing years. The cardiologist also told the family to bring the child back for a follow-up appointment in a year for a repeat echocardiogram to recheck the PFO in an effort to confirm closure. In spite of reassurance that no other activity restrictions were needed, the mother of the child became very concerned about this “heart condition” in her only child. The mother started restricting her from participating in vigorous sports activities such as competitive swimming and gymnastics. The mother also reported anxiety and panic in her child as well as herself, and reported that she was constantly checking her daughter while asleep because she was afraid she might have a stroke in her sleep. The stress had built up to such an extent that the mother had quit her job. The child and family were now referred by her primary care physician to our centre for a second opinion in view of the above-mentioned stress in the family after the diagnosis.
Discussion
Most practicing paediatric cardiologists encounter similar clinical scenarios to the ones above. How a clinician approaches these scenarios is highly variable. It varies from discharging the patient from cardiology follow-up to annual follow-up with echocardiograms to recheck the PFO. In the first case, the patient was counselled reassuringly, whereas in the second case, the counselling for the PFO resulted in significant disruption in the family, with potentially long-lasting impact on the child and her family. Even though, for the cardiologist, it may be a trivial case of a PFO that can be dealt within 15–20 minutes, these cases illustrates how the management/discussion of an incidental finding of PFO in an infant or a child, by the cardiologist, can potentially deleteriously impact the child’s and the family’s life.
Patent foramen ovale (PFO) is defined as a communication between the atria, caused by the incompetence of the valve of the oval fossa. In fetal life, the septum primum or the floor of the oval fossa is normally held away from the edges (limbus) of the oval fossa (septum secundum) due to the higher right atrial pressure. After birth, the increased pulmonary venous return and resultant increased left atrial pressure pushes the septum primum towards the rest of the atrial septum. Eventually, over time, the septum primum completely fuses with the rest of the atrial septum, resulting in complete closure of the communication between the two atria. If this complete closure fails to happen, a small communication (sometimes only a potential communication) remains as a PFO. Until it is completely closed, the shunt is usually left to right. In most individuals, complete closure happens, and therefore there is ultimately no shunting at the level of the atrial septum.
The PFO generally closes within the first few months of age as seen by echocardiogram. However, it has been reported from prior studies that about 25% of the healthy adult population has a PFO. Reference Hagen, Scholz and Edwards1–Reference Homma and Sacco3 The incidence of PFO varies with age. In general, the older the individual, the lower the likelihood of having a PFO. Reference Hagen, Scholz and Edwards1 The frequency of finding a PFO is reported at 34.3% during the first three decades of life, 25.4% during the 4th through 8th decades, and 20.2% during the 9th and 10th decades. Reference Hagen, Scholz and Edwards1 The incidence and size of PFO were reported to be similar in males and females.
A PFO is often found as an incidental finding on paediatric echocardiograms done for other common reasons. When such an incident finding of PFO is noted, the paediatric cardiologists’ approach to this finding could vary from ignoring it completely as a normal variant, all the way to considering it as an abnormality with potential for future problems including a stroke.
The main clinical concern of many paediatric cardiologists is that presence of a PFO is a risk for stroke in the future, which is thought to be the result of paradoxical embolisation of a thrombus from the right to the left side of the circulation. Paediatric stroke is rare and has a reported incidence of 1.1–4.3 per 100,000. Reference Mallick, Ganesan and Kirkham4,Reference Khan, Chan, Mondal and Paes5 The likelihood of identifying the aetiology of a stroke in children is greater than in adults; the majority of cases are associated with prothrombotic disorders or arteriopathy. Reference Hubail, Lemler, Ramaciotti, Moore and Ikemba6 The incidence of cryptogenic stroke in the paediatric population has not been clearly established.
The presence of a PFO in adults has been associated with cryptogenic stroke, sleep apnoea, platypnea–orthodeoxia (breathlessness and desaturation on standing up), deep-sea diving associated decompression illness, high-altitude pulmonary oedema, and migraines. Reference Mojadidi, Christia and Salamon7 The role of a PFO in stroke or stroke recurrence in childhood is unclear and most data is extrapolated from the adult literature. Reference Mojadidi, Mahmoud, Patel, Elgendy and Meier8–Reference Messe, Gronseth and Kent10 Even amongst adults, the mere presence of PFO in an echocardiogram does not mean that they are at risk for stroke. In adults who develop ischaemic stroke, the cause remains uncertain in about 10–40% of the cases and is considered cryptogenic. About 35% of patients with cryptogenic stroke have PFO detected by echocardiogram. However, as a PFO is also detected in about 25% of the general adult population, any PFO in patients with cryptogenic stroke is more likely to be coincidental than causal. Reference Alsheikh-Ali, Thaler and Kent11,Reference Kent, Ruthazer and Weimar12 PFO is not associated with an increased risk of stroke recurrence in adult patients with cryptogenic stroke. Reference Kent, Ruthazer and Weimar12
Transesophageal echocardiography (TEE) is considered the gold standard for the diagnosis of PFO in adults. Given the better acoustic windows in children, transthoracic echocardiogram (TTE) is considered adequate to confirm or exclude the presence of a PFO in most children, without the need for a more invasive TEE. Reference Hubail, Lemler, Ramaciotti, Moore and Ikemba6
Based on the authors’ observation, in some centres, it appears that when an echocardiogram identifies a PFO incidentally in an infant or a child, there is an emerging trend of following these children with periodic echocardiograms. Parents, therefore, often think that their child has a “heart disease”, when it is in fact a variation of no clinical significance in the vast majority, if not all. This, in turn, can lead to undue stress in some families. Some parents may restrict their child from competitive and exertional sports activities, which is an unintended consequence of labelling PFO as a “heart disease”. There is often a subliminal financial incentive to the cardiologist following these “low-risk, high-return” patients annually with a clinic visit and echocardiogram. This is especially true in the current environment of procedure-based incentives for cardiologists. One of the confounding factors in our ability to understand the frequency of this problem results from the fact that the ICD 9 and ICD10 code for a PFO is the same as that of a secundum atrial septal defect. As a result, it is difficult to accurately identify (based on available ICD databases) the frequency with which patients with a diagnosis of PFO are followed in the clinic and undergo annual echocardiograms.
The optimal approach of a PFO with intracardiac shunting in children with stroke is controversial. The current literature review does not support PFO closure for cryptogenic stroke in young adults without an associated risk of venous thromboembolism. The 2016 American Academy of Neurology Practice Advisory recommends that “clinicians should not routinely offer percutaneous PFO closure to patients with cryptogenic ischemic stroke outside of a research setting”. Only in rare circumstances, such as recurrent cryptogenic stroke despite adequate medical therapy, did the American Academy of Neurology recommend to offer PFO closure. Reference Messe, Gronseth and Kent10
Conclusion
In the setting of an isolated PFO in an otherwise healthy infant or young child, further cardiology follow-up is almost always unnecessary. The question, which comes to the mind of the cardiologist, however, is: “do I tell the parents that their child has a hole in the heart and that this puts the child at risk for stroke in their future”. The authors believe that this sort of information to the parents of an infant or young child would not be appropriate. Telling a mother that her child is potentially at risk of stroke is one “fear factor” that will make her return to the cardiologist’s office every year hoping and praying that the PFO closes each time. When she finds that the PFO has not closed each time, it only increases the parents’ mental stress. Sir William Osler aptly said, “the practice of medicine is an art, not a trade; a calling, not a business; a calling in which your heart will be exercised equally with your head”. This statement is true even today nearly a century later. How one approaches the incidental finding of a PFO in a child is a good example of the physician using his heart and head at the same time.
Acknowledgments
The authors thank the patients’ families for their participation in this reporting.
Financial support
This research received no specific grant from any funding agency, commercial, or not-for-profit sectors.
Conflict of interest
None.