Maternal Hyperoxygenation for Left Heart Hypoplasia

(MHO Trial)

Age: 18+

Sex: Female

Trial Phase: Academic

Sponsor: Baylor College of Medicine

Disqualifiers: Multiple gestations, Arrhythmia, Poor ultrasound, others

Compensation: Varies

Number of Visits: Unknown

Duration: Duration of pregnancy

25 Participants Needed

Trial Summary

Do I need to stop my current medications for the trial?

The trial protocol does not specify if you need to stop taking your current medications. However, if you have moderate to severe hypertension requiring medication, you may not be eligible to participate.

What data supports the effectiveness of the treatment Maternal Hyperoxygenation for Left Heart Hypoplasia?

Some studies suggest that maternal hyperoxygenation might modestly increase the size of left heart structures in fetuses with left heart hypoplasia, but its effectiveness is controversial and it may reduce cerebral blood flow, potentially affecting brain development. ^{1 2 3 4 5}

Is maternal hyperoxygenation safe for use in pregnancy?

Maternal hyperoxygenation has been studied for various pregnancy-related conditions, but there are concerns about its safety. Some studies report potential adverse effects, such as reduced cerebral blood flow and possible interference with fetal brain development, suggesting caution in its use. ^{1 2 4 5 6}

How does the treatment Maternal Hyperoxygenation differ from other treatments for hypoplastic left heart syndrome?

Maternal Hyperoxygenation is unique because it involves the mother breathing in extra oxygen to increase blood flow to the fetus's left heart, potentially improving its growth. Unlike other treatments, it is non-invasive and focuses on enhancing fetal heart development during pregnancy, but its effectiveness and safety are still debated. ^{1 2 3 4 7}

What is the purpose of this trial?

Heart disease is the leading cause of infant death related to birth defects. Congenital heart disease in which the left sided structures of the heart (left heart hypoplasia or LHH) are too small are among the most severe, and have some of the highest death and other complication rates.

Research Team

Shaine A Morris, MD

Principal Investigator

Baylor College of Medicine

Eligibility Criteria

This trial is for pregnant women with normal ultrasounds or those whose fetuses have specific heart issues like left heart hypoplasia, at risk of aortic coarctation, or related conditions. It's not for mothers with multiple pregnancies, certain health problems (like severe hypertension), or poor ultrasound images.

Inclusion Criteria

My fetus has a heart condition affecting the left side or aorta.

Group B: Healthy Fetal controls - Mothers undergoing screening fetal echo for family history of CHD with a normal echo; Mothers undergoing fetal echocardiography for suspected heart disease with a normal echo; Mothers evaluated in the fetal center with normal ultrasound

My fetus has a heart condition with specific measurements and blood flow issues.

Exclusion Criteria

Multiple gestations

I have a health condition during pregnancy that could affect my baby's heart and blood flow.

Major extra cardiac anomalies

Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Mothers receive daily maternal hyperoxygenation therapy for the rest of the pregnancy

Duration of pregnancy

Continuous daily treatment

Follow-up

Participants are monitored for safety and effectiveness after treatment

2 years

Treatment Details

Interventions

• Maternal Hyperoxygenation

Trial Overview The study tests if giving extra oxygen to the mother can help babies who might be born with small left-sided heart structures. Mothers breathe in more oxygen and doctors check if it improves the baby's heart condition before birth.

Participant Groups

Group I: Chonic Maternal Hyperoxygenation w/ LHH Experimental Treatment 1 Intervention

Mothers who have a fetus diagnosed with LHH and elect daily maternal hyperoxygenation therapy.

Group II: Acute Maternal Hyperoxygenation with LHH Experimental Treatment 1 Intervention

Mothers who have a fetus diagnosed with LHH and elect acute maternal hyperoxygenation challenge testing.

Group III: Historical LHH Controls Active Control 1 Intervention

Previous women with a dx of fetal LHH and whose care was continued at Texas Children's Hospital.

Group IV: Healthy Fetal Controls Placebo Group 1 Intervention

Healthy mothers with healthy fetuses that will come in monthly for fetal echcos starting at 20 wks.

Who Is Running the Clinical Trial?

Baylor College of Medicine

Lead Sponsor

Trials

1,044

Recruited

6,031,000+

Findings from Research

Maternal hyperoxygenation has been explored since the 1960s as a potential treatment for various obstetric conditions, but there is still no clear evidence supporting its benefits, particularly for fetal growth restriction.

Research on maternal oxygen therapy for fetal congenital cardiac disease has shown mixed results and raised concerns about possible adverse effects, highlighting the need for careful consideration before conducting further clinical trials.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Calling into question the future of hyperoxygenation in pregnancy. McHugh, A., El-Khuffash, A., Franklin, O., et al.[2021]

Chronic maternal hyperoxygenation (CMH) therapy has shown promise in improving fetal pulmonary blood flow and enhancing the growth of the left heart in fetuses with left-sided cardiac defects, potentially leading to better heart structure development as gestation progresses.

Despite its benefits, there are concerns regarding potential fetal complications, such as growth restriction and impacts on brain development, which need to be carefully considered when using CMH therapy.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Successful prenatal treatment with continuous chronic maternal hyperoxygenation therapy in hypoplastic left heart in two pregnancies: Case report. Bolluk, G., Oztarhan, A., Vural, C., et al.[2023]

References

1. United States pubmed.ncbi.nlm.nih.gov

Maternal hyperoxygenation for the human fetus: should studies be curtailed? [2021]

2. England pubmed.ncbi.nlm.nih.gov

Pilot study of chronic maternal hyperoxygenation and effect on aortic and mitral valve annular dimensions in fetuses with left heart hypoplasia. [2017]

3. Germany pubmed.ncbi.nlm.nih.gov

Pulmonary Vasoreactivity to Materno-Fetal Hyperoxygenation Testing in Fetuses with Hypoplastic Left Heart. [2017]

4. Switzerland pubmed.ncbi.nlm.nih.gov

Hypoplastic Left Heart Syndrome: Is There a Role for Fetal Therapy? [2022]

5. Ireland pubmed.ncbi.nlm.nih.gov

Calling into question the future of hyperoxygenation in pregnancy. [2021]

6. United States pubmed.ncbi.nlm.nih.gov

Impact of Maternal Hyperoxygenation on Myocardial Deformation and Loading Conditions in Fetuses with and without Left Heart Hypoplasia. [2022]

7. United States pubmed.ncbi.nlm.nih.gov

Successful prenatal treatment with continuous chronic maternal hyperoxygenation therapy in hypoplastic left heart in two pregnancies: Case report. [2023]