This problem iscongenital(present at birth) and linked to several genetic mutations.
Situs inversus is described in one of two subtypes.
Situs inversus withdextrocardiais the most common form.
Photo composite by Joules Garcia for Verywell Health; Getty Images
Many people with situs inversus can lead normal lives without symptoms.
In normal anatomy, the organs in your chest and abdomen are left-right asymmetrical.
The word “situs” describes the position or orientation of these organs.
The normal anatomy of your organs is described as situs solitus.
This total organ reversal allows your organs to function normally, though on the opposite side of your body.
Long Term, Is Situs Inversus Serious?
The severity and prognosis for situs inversus depends on the pop in of situs inversus present.
People with situs inversus typically have a normal life expectancy.
However, your prognosis can change if you have a heart condition as a result of situs inversus.
Conditions that can occur with situs inversus include respiratory problems, infertility, and heart defects.
About 50% of people with this condition have situs inversus totalis.
The combination of situs inversus totalis and primary ciliary dyskinesia is calledKartagener syndrome.
An additional 12% of people with primary ciliary dyskinesia have situs ambiguous.
Primary ciliary dyskinesia occurs due to defects in the cilia.
Symptoms can vary based on the size of the opening.
A small hole can be asymptomatic, only causing a loudmurmur(noise heard with a stethoscope).
A large hole can interfere with normal breathing, feeding, and growth rate.
The condition can lead to increased lung pressure as more blood than normal is pumped there.
Permanent damage to the lung blood vessels can occur over time.
The disorder creates a situation in which the organs of your body do not get the oxygen they need.
Situs Inversus Diagnosis at Birth vs.
Older Age
Diagnosis at birth can occur in infants whoseprenatal ultrasoundsindicate abnormal organ position before birth.
Babies undiagnosed during the prenatal stage may be born with symptoms that affect their respiratory or cardiac function.
Imaging studies to diagnose these types of complications can reveal the disorder at birth.
However, babies born without symptoms are not routinely screened for the disorder.
Situs inversus can remain asymptomatic throughout a lifetime.
Cross-sectional imaging like CT scans provides the exact anatomical variations in the chest and abdomen.
CT can demonstrate the mirror-image location of the solid organs and a right-sided cardiac apex.
Situs Inversus Genes and Risk Factors
Over 100 genes have been linked to situs inversus defects.
These genes include:
Situs inversus is inherited in an autosomal recessive pattern with multiple gene mutations.
Procedures are performed to facilitate and support people in living a normal life without debilitating symptoms or discomfort.
Specific procedures and treatments, along with changes in your prognosis, vary based on the complications present.
This can involve the use ofantibioticsto treat lung or sinus infections.
Treatment may not be needed for a small hole.
Small ventricular septal defects can close on their own without treatment.
However, a large hole may require repair with open heart surgery.
Correction of a large hole withopen heart surgeryis usually reserved for later in childhood.
A small atrial septal defect doesn’t make your heart work harder, so treatment may be unnecessary.
Some small holes may close on their own.
A large atrial septal defect may be corrected with open heart surgery orcardiac catheterizationin early childhood to prevent complications.
Surgical correction of this defect is always needed.
Organ transplants, especiallyliver transplants, can be a significant challenge.
However, undiagnosed situs inversus can pose problems in emergency situations and even routine health maintenance.
Summary
Situs inversus is a rare congenital condition that occurs in an autosomal recessive pattern.
It involves the mirror-image transposition of the chest and belly organs.
The problem does not reduce lifespan except in the rare cases of certain heart defects.
However, situs inversus can cause symptoms that affect your breathing, fertility, heart, and lungs.
Treatment centers on fixing malfunctions and reducing symptoms.
Since situs inversus can occur without symptoms, you might have this problem without knowing it.
However, it can be found during prenatal ultrasounds or at birth when breathing problems require imaging.
Talk to your healthcare provider about your risk of situs inversus.
A family history of the problem or certain health issues can increase your risk.
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