Diagnosis of Myocardial Ischemia With MCG Using SPECT as a Reference Standard

This study compares a new non-invasive heart scan technology called magnetocardiography (MCG) against the standard nuclear medicine test (SPECT myocardial perfusion imaging) for diagnosing reduced blood flow to the heart (myocardial ischemia). MCG is radiation-free and can be done without stress testing, potentially making heart disease diagnosis safer and more accessible. **You may be eligible if...** - You are 18 or older with symptoms of reduced blood flow to the heart (chest pain or angina) - Coronary angiography or CT has shown less than 70% blockage in your arteries - You have signed informed consent **You may NOT be eligible if...** - You have had a heart attack in the last 48 hours - You have asthma or an allergy to adenosine injection (used in some stress tests) - You have significant left main coronary artery blockage - You have cardiomyopathy (non-ischemic), moderate/severe valve disease, or hemodynamic instability - You have severe heart rhythm problems Talk to your doctor to see if this trial is right for you.