The concern: Lack of research guidance impacts study findings and PE care
Pulmonary embolism (PE) in teens has surged 200% over the past 20 years. Post-PE complications are also on the rise, significantly impacting quality of life when teens are poised to enter adulthood.
The factors contributing to this increase
Many factors may be spurring this increase, explains Ayesha Zia, M.D., Pediatric Hematologist/Oncologist at the Children’s Health℠ Hemostasis Thrombosis Center and Professor at UT Southwestern. “More children have chronic diseases that require hospitalization or central lines, which increase blood clot risk,” she says. “PE is also more common when a teen has obesity or uses oral contraceptives.”
The solution: New pulmonary embolism research
To effectively care for these patients, providers need to understand how PE affects children now and years later. Dr. Zia recently led an effort within the International Society on Thrombosis and Haemostasis (ISTH) neonatal/pediatrics subcommittee to define – for the first time – clinically relevant outcomes for investigators to use when conducting pediatric PE research. Their findings and recommendations appeared in the October 2025 Journal of Thrombosis and Haemostasis (JTH).
Closing the gap: Providing a unified research standard for pediatric PE studies
The JTH article provides a unified research standard for future pediatric PE studies, irrespective of design. “We’re 20 years behind in pediatric research, compared to what we know about PE in adults,” says Dr. Zia. The new standards – which reflect the expertise of three UT Southwestern PE experts and several others – will help close this gap.
The Working Party members reviewed close to 1,000 adult and pediatric PE studies dating back to 1946 and made recommendations in several key areas, including:
Measuring PE-related deaths in children using the adult ISTH definition of 48 hours from PE or deep vein thrombosis (DVT) until the time of death, while highlighting the nuances that must be considered with measuring mortality
Defining thrombolysis-related bleeding as bleeding that occurs within 48 hours of intervention
Diagnosing recurrent PE through comparisons with prior imaging and findings of new vessel involvement, irrespective of timing after the index event
For clinicians, these standardized definitions mean that the studies they rely on for treatment decisions will be more consistent and comparable going forward.
Improving care for children with post-pulmonary embolism syndrome (PPES)
An estimated 40% of children develop post-PE syndrome (PPES), which presents in different ways. In severe cases, fibrous clots can form in the lungs, increasing the risk of chronic thromboembolic pulmonary hypertension (CTEPH) and right-sided heart failure. Dr. Zia is the principal investigator of a groundbreaking study designed to pinpoint the causes of PPES, which may lead to better screening efforts and, by extension, preventive measures and improved treatments.
“After recovering from PE, adolescents who were once active may struggle to keep up with their peers or even climb a flight of stairs,” says Megan Griffiths, M.D., Pediatric Cardiologist at Children’s Health and Director of Pediatric Pulmonary Hypertension for the Division of Pediatric Cardiology at UT Southwestern. Dr. Griffiths, who treats teens with PPES, was a pediatric cardiologist on the ISTH Working Party. “We need to look at outcomes beyond patient survival because PPES can negatively affect a young person’s quality of life, mental health and future,” she says.
PPES causes and cures
To improve research into PPES causes and cures, Dr. Griffiths and other Working Party members, including Tony Babb, Ph.D., an exercise physiologist and member of the Division of Pulmonary and Critical Care Medicine at UT Southwestern, developed research criteria for CTEPH and other types of PPES, including:
Chronic thromboembolic pulmonary disease (CTEPD), persistent blood clots in the lung after anticoagulants but without pulmonary hypertension (PH)
Post-PE cardiac impairment, associated with shortness of breath with exertion or exercise intolerance and right ventricular dysfunction
Post-PE functional limitations, such as new-onset or worsening chest pain, shortness of breath and exercise intolerance
Post-thrombotic stress disorder, including anxiety, depression and post-thrombotic panic syndrome
Depending on symptoms, a patient may need an echocardiogram, cardiopulmonary exercise test and/or ventilation perfusion scan, which is more likely than a CT scan to detect fibrous clots in the lung.
Why Children’s Health for Pulmonary Embolism Care?
Children’s Health has the only pediatric pulmonary hypertension program in North Texas and is among a select few centers nationally with a dedicated Pediatric Hemostasis Thrombosis Center. It’s part of the Pauline Allen Gill Center for Cancer and Blood Disorders (CCBD), the largest center of its kind in North Texas. Dr. Zia and colleagues treat close to 200 blood clots in children every year and approximately one PE each month, making Children’s Health a high-volume center. Dr. Zia shares how she treats pediatric PE in this October 2025 Blood journal article.
In 2021, Children’s Health introduced the nation’s first multidisciplinary pediatric PE Response Team (PERT), detailed in a March 2025 Chest journal article. Children with PPES and other complications receive collaborative care at our nationally rated Heart Center. Here, they undergo comprehensive diagnostic tests and benefit from the latest treatments and ongoing follow-up care, so they can enjoy a more active life throughout childhood and beyond.
Learn more about pediatric blood disorders and thrombosis at Children’s Health.
