Atrial FibrillationNCT07270211
MCG In Long QT Syndrome
An observational study of Atrial Fibrillation, run by Mayo Clinic at 1 site in United States.
Trial summary
The primary objective of this observational study is to evaluate whether magnetocardiography (MCG) findings more accurately predict clinical outcomes in patients with acquired Long QT syndrome compared to ECG. The secondary objective is to assess differences in QT interval length between MCG and ECG. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Atrial Fibrillation
- What is being tested?
- Magnetocardiography
- How many people
- 100 participants
- Where
- 1 siteUnited States
- Study dates
- Sep 2026to Dec 2027
- Phase
- Observational
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Study population: Study candidates may be identified and recruited in one of the following ways: * In-patient service at the study institution. * From the Principal Investigator or Co-Investigator clinical practices * Referral from other hospitals * Cardiology Specialty Clinics
Who may be able to join
- Age ≥ 18 years on the date of consent
- Ability for participant to comply with study requirements
- Written informed consent
- Confirmed diagnosis of atrial fibrillation and receiving dofetilide for rhythm control in the inpatient setting.
Who cannot join
- Pregnant or breastfeeding
- Active thoracic metal implants (including pacemaker, insertable cardiac monitor, or internal defibrillators).
- External electrical pads or devices (e.g. Pacer pads, ECG electrodes, heart rate patch), that must remain on patient's chest during MCG scan
- Inability to lie down in a supine/inclined position and stay still on the examination bed
- Clinical conditions that in the opinion of the Investigator would compromise the safety of the patient or ability to complete the protocol
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
United States1 site
Mayo Clinic in Rochester
Rochester, Minnesota, 55905
Structural Heart Research Team, (507) 255-6133
Mohamad Alkhouli, MD
About this study
Official title: Magnetocardiography in Long QT Syndrome: A Prospective Study of Its Clinical and Prognostic Utility
The primary objective of this observational study is to evaluate whether magnetocardiography (MCG) findings more accurately predict clinical outcomes in patients with acquired Long QT syndrome compared to ECG. The secondary objective is to assess differences in QT interval length between MCG and ECG. The primary safety objective is to characterize the safety profile of the CardiAQ MCG device.
- Conditions
- Atrial Fibrillation
- Being tested
- Magnetocardiography
- Medical subject headings
- Atrial Fibrillation
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
MagnetocardiographyDiagnostic test
MCG is a non-invasive, radiation-free imaging technique that detects the magnetic field generated by the electrical activity of the heart.
| Study group | Role | What they receive |
|---|---|---|
| Subjects diagnosed with atrial fibrillation | Not described Receives: Diagnostic Test: Magnetocardiography |
What is being measured
The primary outcome is the main question the study is designed to answer.
Number of successful dofetilide loading using Magnetocardiography
Dofetilide loading is considered successful if the following conditions are met:
- No excessive QTc prolongation QTc remains <500 ms, and no >15% increase from baseline.
- No sustained VT or recurrent/symptomatic non-sustained VT (NSVT) suggestive of proarrhythmia.
- No symptomatic bradycardia or hemodynamic instability
- Stable renal function
- No deterioration necessitating dose reduction or discontinuation.
- Discharge on a stable dose
Measured: Baseline
Number of successful dofetilide loading using Electrocardiogram
Dofetilide loading is considered successful if the following conditions are met:
- No excessive QTc prolongation QTc remains <500 ms, and no >15% increase from baseline.
- No sustained VT or recurrent/symptomatic non-sustained VT (NSVT) suggestive of proarrhythmia.
- No symptomatic bradycardia or hemodynamic instability
- Stable renal function
- No deterioration necessitating dose reduction or discontinuation.
- Discharge on a stable dose
Measured: Baseline
Secondary outcomes (2)
Magnetocardiography - QT interval length
QT interval length is a measurement from the start of the Q wave to the end of the T wave. This will be measured in seconds.
Measured: Baseline
Electrocardiogram - QT interval length
QT interval length is a measurement from the start of the Q wave to the end of the T wave. This will be measured in seconds.
Measured: Baseline
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted8 Dec 2025
- Study startSep 2026 (estimated)
- Primary completionDec 2027 (estimated)
- Study completionDec 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Atrial FibrillationStudies of the same condition, open and under way.
- More trials run by Mayo ClinicThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Cohort
- Time perspective
- Prospective
- Enrolment
- 100 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Mayo Clinic
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Mohamad Adnan Alkhouli, Mayo Clinic
- Investigators
- Mohamad Alkhouli, M.D., M.B.A., Principal investigator, Mayo Clinic
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07270211
- Sponsor's protocol ID
- 25-008283
- Status last verified
- Jun 2026
- First submitted
- 25 Nov 2025
- Last updated
- 29 Jul 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 29 Jul 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Magnetocardiography in Long QT Syndrome: A Prospective Study of Its Clinical and Prognostic Utility
- ClinicalTrials.gov ID
- NCT07270211
- Acronym / sponsor ID
- 25-008283
- Conditions
- Atrial Fibrillation
- Study type
- Observational
- Recruitment status
- Not yet recruiting
- Enrolment
- 100 participants (estimated)
- Lead sponsor
- Mayo ClinicUniversity, hospital or other
- Study start
- Sep 2026 (estimated)
- Primary completion
- Dec 2027 (estimated)
- Study completion
- Dec 2027 (estimated)
- First posted
- 8 Dec 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The primary objective of this observational study is to evaluate whether magnetocardiography (MCG) findings more accurately predict clinical outcomes in patients with acquired Long QT syndrome compared to ECG. The secondary objective is to assess differences in QT interval length between MCG and ECG. The primary safety objective is to characterize the safety profile of the CardiAQ MCG device.
Study design
- Observational model
- Cohort
- Time perspective
- Prospective
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Subjects diagnosed with atrial fibrillation | – | Diagnostic Test: Magnetocardiography |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
- Study population
- Study candidates may be identified and recruited in one of the following ways: * In-patient service at the study institution. * From the Principal Investigator or Co-Investigator clinical practices * Referral from other hospitals * Cardiology Specialty Clinics
Key inclusion criteria (4 listed)
- Age ≥ 18 years on the date of consent
- Ability for participant to comply with study requirements
- Written informed consent
- Confirmed diagnosis of atrial fibrillation and receiving dofetilide for rhythm control in the inpatient setting.
Key exclusion criteria (5 listed)
- Pregnant or breastfeeding
- Active thoracic metal implants (including pacemaker, insertable cardiac monitor, or internal defibrillators).
- External electrical pads or devices (e.g. Pacer pads, ECG electrodes, heart rate patch), that must remain on patient's chest during MCG scan
- Inability to lie down in a supine/inclined position and stay still on the examination bed
- Clinical conditions that in the opinion of the Investigator would compromise the safety of the patient or ability to complete the protocol
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| MagnetocardiographyMCG is a non-invasive, radiation-free imaging technique that detects the magnetic field generated by the electrical activity of the heart. | Diagnostic test | Subjects diagnosed with atrial fibrillation |
Primary outcome
Number of successful dofetilide loading using Magnetocardiography
Time frame: Baseline
Dofetilide loading is considered successful if the following conditions are met: 1. No excessive QTc prolongation QTc remains <500 ms, and no >15% increase from baseline. 2. No sustained VT or recurrent/symptomatic non-sustained VT (NSVT) suggestive of proarrhythmia. 3. No symptomatic bradycardia or hemodynamic instability 4. Stable renal function 5. No deterioration necessitating dose reduction or discontinuation. 6. Discharge on a stable dose
Number of successful dofetilide loading using Electrocardiogram
Time frame: Baseline
Dofetilide loading is considered successful if the following conditions are met: 1. No excessive QTc prolongation QTc remains <500 ms, and no >15% increase from baseline. 2. No sustained VT or recurrent/symptomatic non-sustained VT (NSVT) suggestive of proarrhythmia. 3. No symptomatic bradycardia or hemodynamic instability 4. Stable renal function 5. No deterioration necessitating dose reduction or discontinuation. 6. Discharge on a stable dose
2 secondary outcomes
Magnetocardiography - QT interval length
Time frame: Baseline
Electrocardiogram - QT interval length
Time frame: Baseline
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 29 Jul 2026.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Mohamad Alkhouli, M.D., M.B.A. principal investigator
Mayo Clinic
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Atrial Fibrillation, run by Mayo Clinic at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 4 inclusion and 5 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: opening soon, as of the sponsor's last update on 29 Jul 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Patsy Caceres Figueroa (507-266-3054, caceresfigueroa.patsy@mayo.edu), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Number of successful dofetilide loading using Magnetocardiography (time frame: Baseline). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 29 Jul 2026.