NCT06188689 · Population Health Research Institute
Evaluation of A Clinical Diagnostic Test for CRDS
(DIAGNOSE CRDS)
What this study is about
Calcium Release Deficiency Syndrome (CRDS) is a novel inherited arrhythmia syndrome secondary to RyR2 loss-of-function that confers a risk of sudden cardiac death. Diagnosis of CRDS presently requires cellular-based in vitro confirmation that an RyR2 variant causes loss-of-function.
View original scientific description
Calcium Release Deficiency Syndrome (CRDS) is a novel inherited arrhythmia syndrome secondary to RyR2 loss-of-function that confers a risk of sudden cardiac death. Diagnosis of CRDS presently requires cellular-based in vitro confirmation that an RyR2 variant causes loss-of-function. We hypothesize that CRDS can be diagnosed clinically through evaluation of the repolarization response to brief tachycardia, mediated by cardiac pacing, and a subsequent pause.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- • Presence of an RyR2 variant confirmed to be loss-of-function on in vitro testing
Exclusion criteria
- • Unable to provide informed consent Cohort 2: Catecholaminergic Polymorphic Ventricular Tachycardia (CPVT) Cases Inclusion criteria:
- Satisfy a clinical phenotype consistent with the Expert Consensus Statement
- Presence of a confirmed or presumed pathogenic gain-of-function RyR2 variant OR homozygous or compound heterozygous for likely pathogenic/pathogenic CASQ2 variants Exclusion criteria:
- Unable to provide informed consent
- Use of a QT prolonging medication, aside from flecainide, at the time of the burst pacing maneuvers Cohort 3: Survivors of Unexplained Cardiac Arrest (UCA) Inclusion criteria:
- Cardiac arrest requiring cardioversion or defibrillation that remains unexplained following an ECG, echocardiogram, coronary assessment, cardiac MRI, and exercise treadmill test
- Undergone genetic testing that includes screening of RyR2\
- Unable to provide informed consent
- Use of a QT prolonging medication at the time of the burst pacing maneuvers
- Among survivors of UCA that possess a rare RyR2 variant in the absence of a CPVT phenotype, in vitro functional testing will be performed in order to confirm it is not loss- or gain-of-function (and will be arranged through the laboratory of Dr. Wayne Chen at the University of Calgary). Cohort 4: SVT controls Inclusion criteria: • Undergoing an invasive electrophysiology study Exclusion criteria:
- Ventricular cardiomyopathy
- Ventricular pre-excitation
- Long QT syndrome
- Use of a QT prolonging medication at the time of the EP study
- Use of a Class I or Class III anti-arrhythmic drug at the time of the EP study
- Known obstructive coronary artery disease (existing coronary stenosis \>50%)
- Unable to provide informed consent
Where
- San Francisco, California
- Rochester, Minnesota
- Seattle, Washington
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Jun 1, 2026 · Source of record for eligibility and locations