Exclusive Interview with Dr. Li Youjin of Ningxia People's Hospital: PFO Closure Shows Significant Efficacy, Yet Widespread Adoption Remains Challenging

During fetal development, each fetus requires a vital pathway to obtain oxygen and nutrients. This pathway is not the pulmonary vasculature, but rather the foramen ovale. Oxygen- and nutrient-rich blood from the maternal umbilical vein passes through the foramen ovale into the fetal left heart system, and is then distributed to various organs throughout the body, ensuring safe fetal development.

After birth, right heart pressure decreases, and left atrial pressure becomes higher than right atrial pressure, leading to the gradual closure of the foramen ovale. If the foramen ovale remains unclosed in children older than three years, it is termed patent foramen ovale (PFO). What is the prevalence of PFO? What are its potential harms? What treatment options are available? To address these questions, VCBeat conducted an exclusive interview with Dr. Li Youjin, Director at the People’s Hospital of Ningxia Hui Autonomous Region.

Dr. Li Youjin serves as Deputy Director of the Cardiovascular Center, Director of the Department of Cardiac and Great Vessel Surgery, and Academic Leader of Cardiac and Great Vessel Surgery at the People’s Hospital of Ningxia Hui Autonomous Region. He also holds various expert and committee positions in multiple professional societies. Dr. Li graduated from Ningxia Medical University in 1999 and completed advanced training in cardiac and great vessel surgery at the Fuwai Hospital, Chinese Academy of Medical Sciences, and the Heart Center of Beijing Anzhen Hospital.Proficient in the diagnosis and treatment of various diseases in cardiothoracic and vascular surgery, with particular expertise in the management of aortic diseases and interventional closure techniques for congenital heart disease, reaching an advanced level within China.

In fact, 25%-30% of adults have a patent foramen ovale (PFO), making it the most common congenital heart defect in adults. Director Li Youjin stated, “Among these adults with PFO, 7%-8% of patients experience symptoms such as migraines, hypoxia, syncope, and shortness of breath, which require medical intervention and treatment.”

For a long time, experts and physicians believed that patent foramen ovale (PFO) had no impact on cardiac hemodynamics and was therefore considered clinically insignificant. However, increasingly in-depth research in recent years has demonstrated a close association between PFO and cryptogenic stroke as well as migraine. Notably, in 2017, the results of several large-scale randomized controlled clinical trials were published in The New England Journal of Medicine, demonstrating thatPFO Closure Is Superior to Long-Term Medical Therapy for Secondary Prevention of Cryptogenic Stroke, indicating an association between patent foramen ovale and cryptogenic stroke.

According to the “2018 Data on Interventional Treatment of Congenital Heart Disease in Mainland China,” released at the 22nd National Forum on Interventional Cardiology in April 2019, a total of 32,961 interventional procedures for congenital heart disease were performed in hospitals across mainland China in 2018. Among these cases, the top five conditions treated were atrial septal defect, patent ductus arteriosus, ventricular septal defect, patent foramen ovale, and pulmonary valve stenosis. Patent foramen ovale ranked fourth, owing to its large affected population. Experts predict that the number of patent foramen ovale closure procedures will continue to grow steadily at certain major medical centers in the near future.

How Does Patent Foramen Ovale Cause Related Diseases? In fact, under normal circumstances, because left atrial pressure is higher than right atrial pressure, no interatrial shunting occurs; therefore, patent foramen ovale (PFO) does not require treatment. However, a PFO with a larger diameter can lead to local blood flow turbulence and thrombus formation. When chronic right atrial pressure increases or suddenly exceeds left atrial pressure, a right-to-left shunt may occur. At this point, various emboli from the venous system can pass through the patent foramen ovale into the left atrium, enter the systemic circulation, and cause paradoxical embolism in the cerebral arteries and/or other arteries, leading to ischemic stroke and other conditions.

Studies have shown that patent foramen ovale (PFO) is significantly positively correlated with the risk of paradoxical embolism or stroke. Compared with normal controls, the relative risk of thromboembolic events in patients with PFO is four times higher, and the risk of thromboembolic events in patients with PFO complicated by atrial septal aneurysm is 33 times higher than that in normal controls. Moreover, there is sufficient evidence indicating that patients with PFO complicated by paradoxical embolism have an increased risk of cerebrovascular events.

Numerous clinical observational studies have found a higher incidence of patent foramen ovale (PFO) in patients with cryptogenic stroke. Director Li Youjin stated, “Existing evidence indicates that PFO closure combined with anticoagulant therapy is more effective than pharmacological therapy alone in preventing stroke recurrence, with a 45% difference in efficacy between the two groups.”

Furthermore, studies have found that patent foramen ovale (PFO) is associated with the pathogenesis of conditions such as decompression sickness and migraine, and PFO closure may be beneficial for patients with these conditions.

Patent Foramen Ovale ClosureClosure of a patent foramen ovale (PFO) is the primary treatment modality for this condition. It is a minimally invasive procedure in which a physician advances a catheter into the left atrium and deploys a dedicated occluder device to seal the foramen ovale, thereby achieving definitive closure of the PFO and preventing complications such as stroke.

“My first encounter with a patient suffering from a patent foramen ovale (PFO) was in 2014. The patient experienced frequent headaches that had become severe enough to interfere with his work. At the time, he visited numerous hospitals and underwent various examinations, including cranial magnetic resonance imaging (MRI), but no specific cause was identified. Despite taking multiple medications, his condition did not improve. Eventually, he came to our hospital, the People’s Hospital of Ningxia Hui Autonomous Region. After a multidisciplinary consultation, we determined that his headaches were caused by a patent foramen ovale. Following PFO closure surgery, the patient’s headaches did not recur, demonstrating a significant therapeutic effect. During the one-year follow-up period, the patient experienced no adverse effects, and his quality of life was markedly improved.”

“In fact, before 2017, there was no clear evidence to prove the efficacy of patent foramen ovale (PFO) closure; only a subset of experts were conducting research in this area, leading many to question the procedure. However, after performing these procedures myself and observing significant clinical benefits, my confidence grew substantially, prompting me to dedicate my research to this field in order to help more patients.”

“Since 2017, with the accumulation of scientific evidence, patent foramen ovale (PFO) closure has gained wider recognition, and the number of procedures performed has been steadily increasing. To date, the People’s Hospital of Ningxia Hui Autonomous Region has performed more than 600 such procedures, including over 200 in 2018 alone, and is projected to perform more than 300 PFO closures this year.”

Diagnosing patent foramen ovale (PFO) as the underlying etiology remains a significant clinical challenge. Patients with PFO present with the characteristic pattern of “cardiac defect, neurological manifestations,” meaning that symptoms such as dizziness and headache originate from cerebral involvement, while the root cause lies in the heart. Consequently, these patients often seek evaluation in neurology departments, where physicians unfamiliar with PFO may fail to identify the true cause. Therefore, it is essential for neurologists to acquire knowledge about PFO and refer such patients to cardiovascular surgery for appropriate management.

Director Li Youjin stated, “The People’s Hospital of Ningxia Hui Autonomous Region has made some attempts in this area, such as organizing training courses on patent foramen ovale (PFO). Our courses are designed for relevant specialists from hospitals across all counties and cities in the Ningxia region. We invite them to review literature together and engage in collaborative discussions on disease management, with the aim of fostering a deeper understanding of PFO. We hope to enable these physicians to accurately diagnose patent foramen ovale, thereby increasing the detection rate and improving patients’ prospects for cure.”

The current surgical volume clearly fails to meet patient demand, making it challenging to promote awareness of this condition and its surgical treatment. Director Li Youjin stated, “In addition to organizing training courses, we invite physicians from departments such as neurology to visit other hospitals for further study, thereby deepening their understanding of the disease. Currently, our hospital is capable of diagnosing this condition and referring patients to our department for treatment, significantly reducing the burden on patients.”

“Additionally, we are currently applying for a science and technology initiative aimed at benefiting the public, with the goal of promoting this technology to county- and city-level hospitals. This would allow patients to receive surgical treatment locally without having to travel long distances to our hospital, thereby enabling more patients to benefit.”

The requirements for performing patent foramen ovale (PFO) closure are not stringent, whereas PFO occluders are essential medical devices.

Director Li Youjin stated, “There are four models of imported patent foramen ovale (PFO) occluders, while domestically produced PFO occluders come in three models. For families with limited financial resources, we recommend the domestic products, as the technology in China is now mature and does not compromise therapeutic efficacy.”

Currently, multiple patent foramen ovale (PFO) occluders in China are undergoing or have completed clinical trials, with several products expected to launch by the end of this year or next year. As previously reported by VCBeat, domestically produced PFO occluders from companies such as Weike Medical are either conducting or preparing for clinical trials, holding promise to contribute to import substitution.

In addition, some domestic enterprises and teams are engaged in product innovation. For instance, the First Affiliated Hospital of Xi’an Jiaotong University, as the lead institution for the “Human Clinical Project on Fully Biodegradable Patent Foramen Ovale (PFO) Occluders,” has developed a fully biodegradable PFO occluder. The first implantation procedure was completed this year, with favorable follow-up outcomes.

Li Youjin, Chief Physician, Associate Professor, and Master’s Supervisor. He currently serves as Deputy Director of the Cardiovascular Center, Director of the Department of Cardiac and Great Vessel Surgery, and Academic Leader of Cardiac and Great Vessel Surgery at Ningxia People’s Hospital.

Graduated from the Department of Clinical Medicine at Ningxia Medical University in 1999, and completed advanced training at the Fuwai Cardiovascular Hospital of the Chinese Academy of Medical Sciences and the Heart and Great Vessel Center of Beijing Anzhen Hospital. Specializes in the diagnosis and treatment of various thoracic and cardiovascular surgical diseases, with domestic advanced-level expertise particularly in the management of great vessel diseases and interventional occlusion techniques for congenital heart disease. Has published more than 10 scientific papers in national journals, served as editor-in-chief for three monographs, presided over two research projects, and participated in more than 10 research projects.