The Heart Rhythm Twins Study

NCT05866731 · Status: COMPLETED · Type: OBSERVATIONAL · Enrollment: 156

Last updated 2026-03-09

No results posted yet for this study

Summary

Premature atrial contractions (PACs) and premature ventricular contractions (PVCs) are observed in the majority of individuals monitored for more than a few hours. Although the clinical course of PACs and PVCs is usually benign, it has been described that high PAC or PVC frequency causes various comorbidities and worsens outcomes in different patient groups. For example, PACs can initiate episodes of atrial fibrillation, and PAC count is highly specific in predicting diagnosis of incident atrial fibrillation. Increasing PVC frequencies are an important predictor of incident heart failure.

While conventional wisdom dictates that common environmental exposures determine PAC and PVC frequencies, this has not born out in rigorous studies. Whether PAC and PVC frequencies may have genetic underpinnings remains unknown.

Comparisons between identical twins and fraternal twins can provide estimates of heritability. Fraternal twins are an ideal control because, like identical twins, they share a womb, have the same birthday, and their environment while growing up are as similar as between identical twins. However, while identical twins share approximately 100% of the same inherited DNA, fraternal twins share, on average, about 50%. By monitoring identical and fraternal twins with portable electrocardiograms (ECGs), we will be able to count the PACs and PVCs over a consecutive timespan to describe the familial aggregation of these complexes. This, to our knowledge, would be the first study to compare PAC and PVC frequencies in identical and same-sex fraternal twins, providing the first assessment of how genetical inheritance may influence cardiac ectopy burdens.

Conditions

  • Premature Atrial Complex
  • Premature Ventricular Contraction

Sponsors & Collaborators

Principal Investigators

  • Greg Marcus, MD, MAS · University of California, San Francisco

Eligibility

Min Age
18 Years
Sex
ALL
Healthy Volunteers
Yes

Timeline & Regulatory

Start
2022-03-22
Primary Completion
2025-03-16
Completion
2025-08-18

Countries

  • United States

Study Locations

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Entities

Read the full study record

This page highlights key information. For complete eligibility criteria, study locations, investigator contacts, and the full protocol, visit the original record on ClinicalTrials.gov.

View NCT05866731 on ClinicalTrials.gov