Use of Magnetocardiography in Evaluation of Patients Going for Cardiac Catheterization

Study Overview
=================
Brief Summary
-----------------
This is a multicenter, prospective trial to measure the test performance characteristics of the Magnetocardiography (MCG) CardioFlux cardiac diagnostic system in detecting clinically significant coronary artery obstruction in patients with symptoms of suspected acute coronary syndrome or who present with a failed stress test with the intention of treat with cardiac catheterization.

Detailed Description
-----------------
This is a multicenter, prospective clinical trial studying the utility and accuracy of magnetocardiography (MCG) in identifying critical coronary artery obstruction responsible for myocardial ischemia. The study will enroll up to 1500 patients at high risk for coronary artery disease (CAD) who have been referred for cardiac catheterization. These patients will be recruited from an inpatient service post admission for chest pain or anginal equivalent or from a cohort of symptomatic patients who have failed outpatient stress testing. If they meet other stated inclusion criteria, they will have a 2 minute MCG scan prior to their cardiac catheterization. For comparative purposes, the first 300 patients will have an electrocardiogram (ECG) performed within 60 minutes of this initial scan. After an enrolled study subject has had their catheterization procedure, the results of the catheterization will be reviewed by one of the study's primary investigators. If the subject has had a percutaneous coronary intervention (PCI), a second MCG scan will be performed prior to their discharge. The MCG scans will be interpreted by 3 physicians trained to read these images and blinded to all clinical information regarding study subjects. The initial MCG scan will be evaluated for its sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and overall accuracy in detecting myocardial ischemia and critical coronary stenosis based on angiographic imaging, fractional flow reserve (FFR), or instant wave-free ratio (iFR) measurements, as applicable. The same statistical analysis will be performed for the ECGs performed on each of the applicable study subjects. When performed, the second MCG will be evaluated for any abnormalities after revascularization. These results will be used to determine the value of post-PCI MCG to predict 30 day and 180 day major adverse cardiac events (MACE)-specifically myocardial infarction or stroke, need for revascularization, or cardiac related death.

Official Title
-----------------
Noninvasive Magnetocardiography Using the CardioFlux (TM) System in the Evaluation of Acute Coronary Syndrome Patients Going for Cardiac Catheterization

Conditions
-----------------
Acute Coronary Syndrome, Coronary Artery Stenosis, Myocardial Ischemia

Intervention / Treatment
-----------------
* Diagnostic Test: CardioFlux Magnetocardiograph


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Age ≥ 18 years of age at the time of enrollment. Patient presenting acutely with signs and symptoms suggestive of Acute Coronary Syndrome (ACS) and in the opinion of the treating physician and based on best clinical assessment that a cardiac catheterization will be performed; or, had a positive stress test and is scheduled for cardiac catheterization. Patient's ability to lay supine for five minutes. Exclusion Criteria: Age < 18 years of age Patients unable to fit into device Unable to transfer to device gantry Positive response on magnetocardiography (MCG) prescreening form Patients with claustrophobia or unable to lie supine for five minutes Pregnant women Poor candidate for follow-up (e.g. no access to phone) Repeat participants Prisoners Acute STEMI or hemodynamically unstable patients (Mean Arterial Pressure ≤ 65, Respiratory Rate ≥24, Heart Rate ≥105 bpm, Temperature>38.1 or <34 degrees Celsius, O2 Saturation<90% despite oxygen therapy). Do not resuscitate order (DNR) Unable to have a cardiac catheterization secondary to dye, allergy, creatinine clearance, can't obtain access, etc.

Ages Eligible for Study
-----------------
Minimum Age: 18 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Intention to Treat: Cardiac Catheterization<br>All patients meeting inclusion criteria and scheduled to undergo cardiac catheterization will undergo a CardioFlux magnetocardiogram (MCG) to determine presence of patterns which indicate myocardial ischemia. | Diagnostic Test: CardioFlux Magnetocardiograph<br>* CardioFlux is a noninvasive diagnostic modality which can measure and image the heart's intrinsic magnetic field created by ion transit across cardiac cell membranes.<br>|
| Post Percutaneous Coronary Intervention<br>All patients found to have significant coronary artery obstruction seen via angiography +/- fractional flow reserve (FFR) or instant wave-free ratio (iFR) and who receive a catheter based intervention will have a post-procedure CardioFlux MCG scan. Follow up over the next 30 and 180 days will be performed to determine if a persistent pattern suggesting residual ischemia will correlate with an increased incidence of major cardiac adverse events (MACE). | Diagnostic Test: CardioFlux Magnetocardiograph<br>* CardioFlux is a noninvasive diagnostic modality which can measure and image the heart's intrinsic magnetic field created by ion transit across cardiac cell membranes.<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Accuracy of MCG to detect myocardial ischemia as determined by cardiac catheterization | Assess accuracy of CardioFlux MCG (MCG-CF) and magnetic field map characteristics with findings of significant coronary artery stenosis ≥70% via angiography and/or via FFR of <0.8 or via instant wave-free ratio (iFR) . | 72 hours | 
| Accuracy of MCG vs. ECG | Compare CardioFlux MCG accuracy to ECG accuracy in identifying cardiac ischemia using coronary angiography with or without FFR/iFR as gold standard. | 72 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incident of post-PCI MACE | Determine if residual abnormalities on post PCI MCG-CF maps can predict 30 day and 180 day MACE. | 6 months | 
| Inter-reader reliability percentage | Measurement of consistency of interpretation among 3 physician readers of CardioFlux MCG scans. | 6 months | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
Coronary Artery Disease, Myocardial ischemia