The purpose of this research study is to evaluate a better way of diagnosing heart artery
disease, heart attack and damage to the heart muscle early on. Currently, it often takes
several hours after admission before lab tests will show that there has been any damage to
the heart muscle. Although the standard electrocardiogram is quick and non-painful it may
miss many cases of significant coronary heart disease. The investigators are proposing that
a new entirely non-contact tool, the Magnetocardiograph (MCG), with high accuracy is able to
predict the presence of significant coronary heart disease early on before other studies
become positive. The investigators hope by this that the investigators can develop an
algorithm for better triage and management of patients with chest pain.
This research study is designed to test the effectiveness of the investigational use of the
Magnetocardiograph (MCG) that has been approved by the U.S Food and Drug Administration
(FDA). While the MCG used in the study is FDA-approved as a tool for the non-contact
measurement and display of the magnetic fields of the heart generated by the electrical
currents, it is not yet approved for the specific diagnosis of heart artery disease
Cardiomagnetism refers to the detection, analysis and interpretation of the magnetic fields
generated by the electrical activity of the heart. The peak value of the magnetic fields of
the heart is more than a million times smaller than the Earth's magnetic field. A major
breakthrough in the capability of measuring such small fields came with the invention of the
SQUID (superconducting quantum interference device) in the late sixties. The first
magnetocardiograms (MCGs) measured with the SQUID were recorded by Cohen et al. in 1970 (1).
These earlier measurements were performed in very expensive magnetically shielded rooms,
initially utilizing only one or two SQUID probes. In the eighties this technology was tested
in several laboratories creating a magnetic field map by moving one SQUID sequentially above
the chest to create an image of the whole hearts magnetic field. These maps were then
attempted correlated with various pathologies (2,3).
Since then the technology has been greatly improved and several multichannel machines are in
use across the world for research purpose for arrhythmia localization and ischemia
detection. However, at present time, only one company (CardioMag Imaging) has developed a
machine that operates outside a shielded room.
The CardiomagImaging (CMI) Magnetocardiograph (MCG) is capable of noninvasive recording of
magnetic fields arising from the electrical activity of the heart with very high spatial and
temporal resolution. The temporal trace of the MCG is analogous to an ECG, and, similarly,
can be recorded in multiple leads. This MCG device has been specifically developed for the
general purpose (outside shielded room) of non-contact, non-invasive diagnostics of
The CMI MCG device has been approved as safe for patients. It is FDA approved for the
noninvasive detection and display of the heart's magnetic field created by the electrical
currents, and is awaiting FDA approval for the detection of ischemia in chest pain patients.
A similar SQUID technology utilized in magnetically shielded rooms has already been FDA
approved for localization of epileptic focus. When utilized in this matter it is referred to
as MEG (magnetoencephalogram).
Several abstracts have been presented primarily at meetings on Biomagnetism, that confirm
the safety and indicate the efficacy of the MCG for the detection of ischemia. In
particular, it has been suggested that the resting MCG is capable of detecting ischemia in
patients with chest pain, when the 12-leads ECG is normal (4,5,6). However, this has not
been tested in larger prospective blinded studies.
Cedars-Sinai Medical Center Non-invasive Cardiac Laboratory will be the first center in the
US evaluating the CardioMag Imaging MCG in a clinical environment for the detection of
ischemia in an acute coronary syndrome patient population. Patients will be enrolled in a
similar protocol at Johns Hopkins Medical Center, Baltimore, Mayo clinic, Rochester, and at
Klinikum Hoyerswerda, Germany. The early detection of ischemia (before Troponins become
positive) with high negative and positive predictive values may prove cost effective and
decrease risk by improving prompt treatment and triage to higher or lower grade monitoring
at time of hospitalization.
- Patients with chest pain syndrome
- ST elevation MI
- Hemodynamically unstable patients
- Tachycardia with heart rate >150 just prior to testing or at time of testing
- A-V Dissociation on 12-lead ECG
- Patients with pacemakers or internal defibrillators
- Minors < 18 years of age
- Patients unable to lie flat for the examination