Purpose

Few studies are specifically designed to address health concerns that are already relevant during pregnancy. The consequence is a lack of evidence on best clinical practice. This includes mothers and their babies when pregnancy is complicated by an abnormally slow heart rate due to maternal antibody-mediated heart disease in the unborn baby (fetus). Since the late seventies, it has been possible to detect and monitor fetal disease by ultrasound images and to treat selected conditions with pharmaceuticals administered via the mother. To this day, physicians need to make decisions about the management of such pregnancies without evidence from prospective clinical trials on drug efficacy and safety. The SLOW HEART REGISTRY is a multi-centered prospective observational study that will address the knowledge gap to guide future management of high-degree immune-mediated heart block to the best of care. The study seeks to establish an international database of the management and outcome of affected fetuses, to be used to publish information on the results of currently available prenatal care and to evaluate the need for additional research.

Conditions

Eligibility

Eligible Ages
Between 16 Years and 50 Years
Eligible Genders
Female
Accepts Healthy Volunteers
No

Inclusion Criteria

  • Written informed maternal consent to participate in the Slow Heart Registry - High-degree (2nd; 2:1; 2nd-3rd or 3rd degree) AVB diagnosed ≤ 32+0 weeks with or without hydrops - Enrollment within maximally 8 days of high-degree AVB diagnosis - Positive or pending anti-Ro/La antibody test results at the time of enrollment

Exclusion Criteria

  • AVB associated with major CHD (e.g. left atrial isomerism, cc-TGA) - AVB with known negative anti-Ro and/or La antibody test result at enrollment - 1st degree AVB - Sinus bradycardia with normal 1:1 AV conduction - Blocked atrial bigeminy (irregular atrial rate with failure of AV conduction of the premature atrial beat) - Primary delivery for postnatal treatment - Maternal-fetal conditions (other than cardiac NL) associated with high odds of premature delivery or death (e.g. renal failure, significant infectious diseases, major extracardiac anomalies, PROM, etc.) - Preexisting maternal mental disorder (e.g. bipolar, mania, severe depression, substance abuse) - Poorly controlled insulin-dependent diabetes (HbA1c >7%) at CAVB diagnosis - Oligohydramnios (deepest/maximal vertical pocket <2 cm) - Severe IUGR (estimated fetal weight <3rd percentile)

Study Design

Phase
Study Type
Observational [Patient Registry]
Observational Model
Cohort
Time Perspective
Prospective

Arm Groups

ArmDescriptionAssigned Intervention
Prospective observational cohort 1 Complete AVB (3rd degree) diagnosed ≤ 32+0 weeks with or without hydrops
  • Drug: Dexamethasone
    All management decisions are made by the primary physician and may include: 1) no treatment with dexamethasone or 2) treatment with dexamethasone from the time of enrollment
  • Other: No Dexamethasone
    All management decisions are made by the primary physician and may include: 1) no treatment with dexamethasone or 2) treatment with dexamethasone from the time of enrollment
Prospective observational cohort 2 Incomplete AVB (2nd; 2:1; 2nd-3rd degree) diagnosed ≤ 32+0 weeks with or without hydrops
  • Drug: Dexamethasone
    All management decisions are made by the primary physician and may include: 1) no treatment with dexamethasone or 2) treatment with dexamethasone from the time of enrollment
  • Other: No Dexamethasone
    All management decisions are made by the primary physician and may include: 1) no treatment with dexamethasone or 2) treatment with dexamethasone from the time of enrollment

Recruiting Locations

Children's National and nearby locations

Children's National Medical Center
Washington, District of Columbia 20010
Contact:
Mary Donofrio, MD

More Details

NCT ID
NCT04559425
Status
Recruiting
Sponsor
The Hospital for Sick Children

Study Contact

Diana Balmer-Minnes, BSc, CCRP
416-813-7654
slow.heart@sickkids.ca

Detailed Description

The SLOW HEART REGISTRY is a multi-centered prospective observational study of fetuses diagnosed with high-degree immune-mediated atrio-ventricular heart block (AVB). The study seeks to establish an international database of the management and outcome of affected fetuses, to be used to publish information on the results of currently available prenatal care and to evaluate the need for additional research. The study aims are to document the outcome of patients diagnosed prenatally with immune-mediated 2nd or 3rd degree AVB irrespective of the primary choice of prenatal care. The primary objective will be to determine the rate of transplant-free survival to 1 year of life of fetuses with AVB based on the prenatal management decision: - Cohort 1: Fetuses not treated with fluorinated glucocorticoids - Cohort 2: Fetuses treated with fluorinated glucocorticoids from the time of immune-mediated AVB diagnosis. Secondary objectives will be to determine: 1. the evolution of clinical findings from AVB diagnosis to birth (AV conduction; fetal heart rate; other NL manifestations; fetal growth; effusions/hydrops) between cohorts; 2. the need of new/additional treatment (steroids; beta-mimetics; IVIG) to birth; 3. gestational age and weight at birth; 4. postnatal management (pacing; steroids; IVIG); and 5. clinical evolution from birth to 1-3 years of life (cardiac function; developmental milestones; infant growth; health). Prevalence of relevant fetal-maternal events and complications (death; IUGR; morbidity) between the study cohorts will also be determined. All management is decided by the treating center and physicians in accordance to institutional guidelines and clinical findings. Patient enrollment in the SLOW HEART REGISTRY is possible within up to 8 days of the initial management decision. Participation in this prospective observational cohort study requires site REB approval and an executed legal contract with the primary investigator/SickKids Hospital, Toronto.

Notice

Study information shown on this site is derived from ClinicalTrials.gov (a public registry operated by the National Institutes of Health). The listing of studies provided is not certain to be all studies for which you might be eligible. Furthermore, study eligibility requirements can be difficult to understand and may change over time, so it is wise to speak with your medical care provider and individual research study teams when making decisions related to participation.