An observational study in Atrial Fibrillation, Ventricular Tachycardia and Premature Ventricular Contraction, sponsored by Vanderbilt University Medical Center. Recruiting at 1 site in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-05-06.
Sponsored by Vanderbilt University Medical Center · Observational
The goal of this observational study is to determine if electrophysiologic mapping and cardiac MRI can help identify patients that have genetic forms of cardiomyopathy that are at high risk for development of dangerous ventricular arrhythmias.
The investigators aim to study:
Participants will undergo cardiac MRI before their scheduled procedure and voltage mapping during their scheduled procedure as part of data collection.
New genomic knowledge is poised to change clinical practice for atrial fibrillation (AF). In 1293 cases previously considered idiopathic, the investigators identified a pathogenic variant in a cardiomyopathy (CM) or arrhythmia gene in \~11% of patients diagnosed with AF before age 608 and went on to show that these patients have a higher risk of mortality and sudden death. The investigators propose tests of specific hypotheses that will address the major knowledge gap of whether and how genetic findings should change clinical management recommendations.
Aim: To use programmed ventricular stimulation at the time of AF ablation or Electrophysiology Study to define the prevalence and mechanism of inducible ventricular tachycardia (VT) (Aim 1A); pace-mapping to define the site of origin of ventricular arrhythmias (Aim 1B); and voltage mapping to define low voltage scar substrate in the basal LV (Aim 1C) in patients with pathogenic TTN variants compared to genotype-negative controls.
The Aim is informed by the observation that life-threatening VT in patients with dilated CM and pathogenic TTN variants most often localizes to the LV outflow tract (LVOT), periaortic region, and basal septum. The investigators found that 39% (27/70) of patients with early-onset AF and pathogenic TTN variants have premature ventricular contractions (PVCs) and non-sustained VT that localize to this same area, which the investigators therefore hypothesize are an early marker of a malignant arrhythmia substrate. Life-threatening ventricular arrhythmias are usually due to scar-related reentry, but a major problem with the LVOT/periaortic region is that scar in this area is hard to detect. To address this limitation, the investigators have published new voltage cutoffs to define scar in the LVOT/periaortic region. The Aim addresses the overarching hypothesis that patients with pathogenic TTN variants have occult scar in the basal LV and are at risk for life-threatening reentrant VT. The investigators will define the mechanism of VT using a combination of entrainment maneuvers with overdrive pacing and the identification of scar with voltage mapping. To facilitate the Aim, the investigators have established a dedicated AF Precision Medicine Clinic to evaluate patients with early onset AF. Fifty percent of these patients undergo AF ablation for symptomatic AF, which the investigators have found is as effective in TTN patients as genotype-negative controls. The investigators will enroll 50 patients with a pathogenic variant in TTN, 50 with a pathogenic variant in other CM genes (e.g., LMNA), and 100 genotype-negative controls.
4,009 studies on the registry are indexed under Atrial Fibrillation; 961 are open to participants now.
This study's planned enrollment of 200 is below the median of 300 across 1,400 observational studies indexed under Atrial Fibrillation.
Browse Atrial Fibrillation studies →Vanderbilt University Medical Center is the lead sponsor of 833 studies on the registry; 155 are open to participants now.
Of its 125 completed or terminated interventional studies of FDA-regulated products, 92 (74%) have results posted.
Counted across the registry records on this site, refreshed daily.
Young patients with atrial fibrillation, frequent PVCs, or VT that are scheduled to undergo procedural management of their arrhythmia.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
The share of blood the heart’s main pumping chamber (the left ventricle) pushes out with each beat, measured by an echocardiogram (heart ultrasound) or a MUGA scan. About 50–70% is normal.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
LVEF (left ventricular ejection fraction)
The share of blood the heart’s main pumping chamber (the left ventricle) pushes out with each beat, measured by an echocardiogram (heart ultrasound) or a MUGA scan. About 50–70% is normal.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Patients with a pathogenic or likely pathogenic variant in TTN on clinical genetic testing.
Patients with a pathogenic or likely pathogenic variant in a gene other than TTN on clinical genetic testing.
Patients without a pathogenic or likely pathogenic variant in a cardiomyopathy or arrhythmia gene on clinical genetic testing.
Ventricular Tachycardia Inducibility
Patients will undergo an electrophysiology study (EP study) as part of the research or clinical protocol for the procedure. Inducible VT (yes/no) with the EP study will be the primary outcome measure.
Time frame: During procedure
Site and Substrate of Ventricular Ectopy
Localization of ventricular ectopy or arrhythmia will be evaluated during the procedure by electoanatomic mapping, and the assessment of scar burden in this area (by voltage mapping) will be secondary outcomes for Aims 1B and 1C.
Time frame: During procedure
Started Dec 2023 (actual). Primary completion is estimated for Dec 2028, 60 months after the start.
Of 550 non-industry observational studies under Atrial Fibrillation, half reached primary completion within 46 months of starting (the median), counting those still running; a quarter within 25 and three quarters within 91. This study's planned 60 months is above that.
Counting every sponsor, half of 698 studies reached it within 38 months; a quarter within 22 and three quarters within 76.
How these figures are worked out, and which studies are left out of them.
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