Overview
Visceral heterotaxy, also known as heterotaxy syndrome or situs ambiguus, is a rare condition where the internal organs of the chest and abdomen are not arranged in their normal positions. In a typical body, the heart sits slightly to the left, the liver is on the right, and the stomach and spleen are on the left. In heterotaxy, this normal left-right arrangement is disrupted, and organs may be mirrored, duplicated, absent, or placed in unusual positions. The word 'heterotaxy' comes from Greek words meaning 'different arrangement.' The heart is almost always affected, and most people with heterotaxy have complex congenital heart defects that require surgery. There are two main types: asplenia syndrome (also called right isomerism), where the spleen is absent and both sides of the body look like the right side; and polysplenia syndrome (also called left isomerism), where there are multiple small spleens and both sides resemble the left side. Other organs like the lungs, liver, intestines, and bile ducts can also be abnormally positioned or formed. Symptoms depend on which organs are affected and how severely. Heart problems are the most serious concern and can cause breathing difficulties, bluish skin color, and poor feeding in newborns. Digestive problems, repeated infections (especially without a working spleen), and abnormal lung structure are also common. Treatment focuses on correcting heart defects through surgery, preventing infections, and managing complications from other affected organs. Care requires a team of specialists working together throughout a person's life.
Also known as:
Key symptoms:
Complex heart defects present from birthBluish or purplish skin color (cyanosis) due to low oxygen levelsDifficulty breathing, especially in newbornsPoor feeding and slow weight gain in infantsOrgans in unusual positions (heart, liver, stomach, spleen)Absent spleen, leading to increased risk of serious infectionsMultiple small spleens that may not work properlyAbnormal lung structure or lung lobesIntestinal malrotation, which can cause bowel blockagesJaundice or liver and bile duct problemsRepeated or severe bacterial infectionsAbnormal heart rhythm (arrhythmia)Fatigue and low energy due to heart or lung problems
Multifactorial
Caused by a mix of several genes and environmental factors
Neonatal
Begins at or shortly after birth (first 4 weeks)
FDA & Trial Timeline
4 eventsYonsei University — NA
Heinrich-Heine University, Duesseldorf
Edwards Lifesciences — NA
Data sourced from FDA regulatory filings and ClinicalTrials.gov. Updated periodically.
Treatments
No FDA-approved treatments are currently listed for Visceral heterotaxy.
2 clinical trialsare actively recruiting — trials can provide access to cutting-edge therapies.
View clinical trials →Treatment Centers
8 centersBaylor College of Medicine Rare Disease Center ↗
Baylor College of Medicine
📍 Houston, TX
🏥 NORDStanford Medicine Rare Disease Center ↗
Stanford Medicine
📍 Stanford, CA
🔬 UDNNIH Clinical Center Undiagnosed Diseases Program ↗
National Institutes of Health
📍 Bethesda, MD
🔬 UDNUCLA UDN Clinical Site ↗
UCLA Health
📍 Los Angeles, CA
🔬 UDNBaylor College of Medicine UDN Clinical Site ↗
Baylor College of Medicine
📍 Houston, TX
🔬 UDNHarvard/MGH UDN Clinical Site ↗
Massachusetts General Hospital
📍 Boston, MA
🏥 NORDMayo Clinic Center for Individualized Medicine ↗
Mayo Clinic
📍 Rochester, MN
👤 Mayo Clinic Center for Individualized Medicine
🏥 NORDUCLA Rare Disease Day Program ↗
UCLA Health
📍 Los Angeles, CA
Travel Grants
No travel grants are currently matched to Visceral heterotaxy.
Community
No community posts yet. Be the first to share your experience with Visceral heterotaxy.
Start the conversation →Latest news about Visceral heterotaxy
Disease timeline:
New recruiting trial: METABolic Deterioration in HTX Determines Outcomes
A new clinical trial is recruiting patients for Visceral heterotaxy
Caregiver Resources
NORD Caregiver Resources
Support, advocacy, and financial assistance for caregivers of rare disease patients.
Mental Health Support
Rare disease caregiving can be isolating. Connect with counseling and peer support.
Family & Caregiver Grants
Financial assistance programs specifically for caregivers of rare disease patients.
Social Security Disability
Learn how rare disease patients may qualify for SSDI/SSI benefits.
Questions for your doctor
Bring these to your next appointment
- Q1.Which specific organs are affected in my child's case, and how does that change the treatment plan?,Does my child have a working spleen, and if not, what infection prevention steps do we need to follow every day?,What heart surgeries will my child need, and what is the expected timeline?,Should our family have genetic testing, and what does it mean for future pregnancies?,What signs of complications should prompt an emergency room visit?,What are the long-term health risks as my child grows into adulthood, and when should we transition to an adult specialist?,Are there clinical trials or research studies that my child might be eligible for?
Common questions about Visceral heterotaxy
What is Visceral heterotaxy?
Visceral heterotaxy, also known as heterotaxy syndrome or situs ambiguus, is a rare condition where the internal organs of the chest and abdomen are not arranged in their normal positions. In a typical body, the heart sits slightly to the left, the liver is on the right, and the stomach and spleen are on the left. In heterotaxy, this normal left-right arrangement is disrupted, and organs may be mirrored, duplicated, absent, or placed in unusual positions. The word 'heterotaxy' comes from Greek words meaning 'different arrangement.' The heart is almost always affected, and most people with het
How is Visceral heterotaxy inherited?
Visceral heterotaxy follows a multifactorial inheritance pattern. Genetic counseling can help families understand recurrence risk and testing options.
At what age does Visceral heterotaxy typically begin?
Typical onset of Visceral heterotaxy is neonatal. Age of onset can vary across affected individuals.
Are there clinical trials for Visceral heterotaxy?
Yes — 2 recruiting clinical trials are currently listed for Visceral heterotaxy on UniteRare. See the clinical trials section on this page for phase, sponsor, and site details sourced from ClinicalTrials.gov.
Which specialists treat Visceral heterotaxy?
4 specialists and care centers treating Visceral heterotaxy are listed on UniteRare, sourced from ClinicalTrials.gov principal investigators, published research, and the NPPES NPI registry.