According to Gram Research analysis, vitamin A signaling in blood vessel cells decreases after Glenn surgery for single ventricle heart disease, and this decrease appears to trigger abnormal blood vessel formation in the lungs. A 2026 rat model study found that dietary vitamin A deficiency worsened these abnormal blood vessels, while excess vitamin A reduced their severity, suggesting vitamin A supplementation might prevent this common surgical complication.
Researchers discovered that children born with single ventricle heart disease often develop abnormal blood vessels in their lungs after a common surgical procedure called Glenn surgery. Using rat models and advanced genetic analysis, scientists found that vitamin A signaling in blood vessel cells decreases after this surgery, similar to what happens in a genetic condition called hereditary hemorrhagic telangiectasia. When rats were given extra vitamin A in their diet, the severity of these abnormal blood vessels decreased. This finding suggests that vitamin A supplementation might become a new treatment option to prevent these dangerous complications in heart patients.
Key Statistics
A 2026 research article published in JACC Basic to Translational Science found that approximately 17 percent of gene expression changes in blood vessel cells after Glenn surgery involved vitamin A signaling pathways.
In rat models of Glenn surgery, dietary vitamin A deficiency increased the severity of pulmonary vascular malformations, while excess dietary vitamin A intake mitigated this severity, according to a 2026 study.
Researchers identified that gene expression changes in blood vessel cells after Glenn surgery share similar patterns with hereditary hemorrhagic telangiectasia, a genetic condition causing abnormal blood vessel formation, suggesting common underlying mechanisms.
The Quick Take
- What they studied: Whether vitamin A levels affect the development of abnormal blood vessels in the lungs of patients with single ventricle heart disease after Glenn surgery.
- Who participated: Surgical rat models designed to mimic the Glenn circulation procedure used in human heart patients, along with genetic analysis of blood vessel cells.
- Key finding: Rats with low dietary vitamin A developed more severe abnormal blood vessels, while rats given extra vitamin A had reduced severity of these complications. About 17 percent of gene expression changes in blood vessel cells after surgery involved vitamin A signaling pathways.
- What it means for you: This research suggests that vitamin A supplementation might help prevent dangerous blood vessel complications in heart patients who undergo Glenn surgery, though human clinical trials are needed before this becomes standard treatment.
The Research Details
Researchers used surgical rat models that replicate the Glenn procedure, a common operation for babies born with single ventricle heart disease. After surgery, they analyzed gene expression in lung blood vessel cells using single-cell RNA sequencing, a technology that reads the genetic instructions active in individual cells. This allowed them to identify which genes were turned on or off after surgery. They then tested whether changing dietary vitamin A levels in rats would affect the development of abnormal blood vessels. The study compared three groups: rats with normal vitamin A intake, rats with vitamin A deficiency, and rats given excess vitamin A.
Understanding the genetic changes that occur after Glenn surgery is crucial because virtually all patients develop these abnormal blood vessels, yet doctors don’t know how to prevent them. By identifying vitamin A signaling as a key mechanism, researchers found a potentially modifiable factor that could be adjusted through diet or supplements. This approach is more practical than trying to change complex genetic pathways directly.
The study used advanced genetic sequencing technology to identify specific cellular changes, which provides detailed molecular information. The researchers validated their findings by comparing results across multiple rat models and by noting similarities to a known genetic condition affecting blood vessels. However, this is animal research, so results may not directly translate to humans. The study was published in a peer-reviewed journal focused on translational science, meaning it bridges basic research and clinical applications.
What the Results Show
Researchers found that after Glenn surgery in rats, blood vessel cells showed significant changes in gene expression, with vitamin A signaling pathways being notably decreased. Approximately 17 percent of all genes that changed their activity in blood vessel cells after surgery were related to vitamin A signaling. When researchers compared these findings to genetic data from patients with hereditary hemorrhagic telangiectasia, a condition causing abnormal blood vessel formation, they discovered striking similarities in which genes were affected. This suggested that vitamin A signaling disruption might be a common mechanism underlying abnormal blood vessel development in different conditions. When rats were fed a diet deficient in vitamin A, they developed more severe abnormal blood vessel shunting in their lungs, meaning blood was bypassing normal lung tissue. Conversely, when rats received excess dietary vitamin A, the severity of these abnormal blood vessels decreased significantly.
The study identified that the genetic changes in blood vessel cells after Glenn surgery share common pathways with hereditary hemorrhagic telangiectasia, suggesting that treatments developed for that genetic condition might also help Glenn surgery patients. The research also demonstrated that dietary vitamin A is a modifiable factor, meaning it can be changed through supplementation or dietary adjustment, making it a practical potential intervention.
Previous research has shown that abnormal blood vessel development is nearly universal in single ventricle patients after Glenn surgery, but the underlying cause has remained mysterious. This study is the first to identify vitamin A signaling as a key mechanism and to demonstrate that modifying vitamin A intake can reduce the severity of these complications. The connection to hereditary hemorrhagic telangiectasia is novel and opens new avenues for understanding both conditions.
This research was conducted in rats, not humans, so the results may not directly apply to patients. The study did not test vitamin A supplementation in actual Glenn surgery patients, only in animal models. The optimal dose and timing of vitamin A supplementation remain unknown. Additionally, the study did not examine whether vitamin A supplementation could completely prevent abnormal blood vessel development or only reduce its severity. Long-term effects of vitamin A supplementation were not evaluated.
The Bottom Line
Based on this research, vitamin A supplementation appears promising as a potential preventive treatment for abnormal blood vessels after Glenn surgery, though human clinical trials are needed before this becomes standard medical practice. Patients and families should not self-supplement with vitamin A without medical guidance, as excessive vitamin A can be toxic. Healthcare providers caring for Glenn surgery patients should consider this research when counseling families about future treatment options.
This research is most relevant to families with children who have single ventricle heart disease and are scheduled for or have undergone Glenn surgery. Cardiologists and cardiac surgeons treating these patients should be aware of these findings. Researchers studying hereditary hemorrhagic telangiectasia may also find this work valuable. People without heart disease do not need to change their vitamin A intake based on this study.
If vitamin A supplementation becomes a clinical treatment, benefits would likely need to be assessed over months to years following Glenn surgery, as abnormal blood vessel development is a gradual process. Researchers would need to conduct human trials to determine the appropriate timing and dosage of supplementation.
Frequently Asked Questions
What is Glenn surgery and why do patients develop blood vessel problems after it?
Glenn surgery is a procedure for babies born with single ventricle heart disease, where only one pumping chamber works. Nearly all patients develop abnormal blood vessels in their lungs afterward, but doctors didn’t know why until this research identified vitamin A signaling as a key factor.
Can I give my child vitamin A supplements to prevent blood vessel problems after heart surgery?
This research is promising but still in animal testing stages. Do not start supplements without consulting your child’s cardiologist. Excessive vitamin A can be harmful. Wait for human clinical trials before making treatment decisions.
How does vitamin A help prevent abnormal blood vessel formation?
Vitamin A activates signaling pathways in blood vessel cells that appear to prevent abnormal vessel development. When vitamin A signaling decreases after Glenn surgery, abnormal blood vessels form more readily. Restoring vitamin A levels may restore normal vessel development.
Is this research ready to be used as a treatment for heart patients?
Not yet. This study used rat models, not human patients. Researchers must conduct human clinical trials to determine safe and effective vitamin A dosing before it becomes standard treatment for Glenn surgery patients.
What foods contain vitamin A for heart health?
Vitamin A-rich foods include sweet potatoes, carrots, spinach, kale, and liver. However, dietary sources alone may not provide therapeutic levels needed to prevent post-surgical complications. Medical supplementation would require doctor supervision.
Want to Apply This Research?
- For cardiac patients, track dietary vitamin A intake in milligrams per day and correlate with any imaging studies or clinical assessments of lung blood vessel function over time.
- If recommended by a cardiologist, users could log daily vitamin A supplementation or dietary sources of vitamin A, such as sweet potatoes, carrots, spinach, and kale, to maintain consistent intake levels.
- Establish a long-term tracking system that records vitamin A intake alongside any clinical follow-up appointments, imaging results, or symptom changes related to lung function or exercise tolerance.
This research is based on animal models and has not yet been tested in human patients. Vitamin A supplementation should only be undertaken under medical supervision, as excessive vitamin A intake can be toxic. Parents and patients with single ventricle heart disease should discuss these findings with their cardiologist before making any changes to vitamin intake or supplementation. This article is for educational purposes and should not replace professional medical advice. Always consult with qualified healthcare providers before starting new supplements or treatments.
This research translation is published by Gram Research, the science division of Gram, an AI-powered nutrition tracking app.