Cardiac Clinical Application of Magnetocardiographic Mapping

After 40 years of experimental recordings and interdisciplinary interaction, several clinical application of Multichannel Magnetocardiography (MMCG) have been finally identified and are currently under extensive validation around the world. At the moment the most relevant efforts are surely devoted to investigate the predictive value of magnetocardiographic (MCG) parameters used for early diagnosis of coronary artery disease (CAD). This is considered a major issue for a definitive acceptance of MMCG as an innovative method for the emergency ¿triage¿ and early treatment of patients with chest pain and suspected acute coronary syndrome (ACS), which might present with ECG and enzyme patterns still negative or non-diagnostic. As a consequence differentiation criteria among MCG abnormalities due to CAD from those due to other cardiomyopathies are needed and under investigation. Although apparently disregarded for many years, a renewed interest for MCG to monitor rejection reactions in patients with transplanted heart has been recently reported. 3D imaging and localization of cardiac arrhythmias and arrhythmic risk assessment have been among the first clinical applications of MMCG and represent significant fields of interest still now. In fact, recently published comparative studies have demonstrated the additional predictive value of MMCG for arrhythmic risk assessment as compared to ECG methods. On the other hand, the accuracy of MCG source localization has been definitely demonstrated and this powerful feature of MMCG has triggered the development of multimodal cardiac imaging techniques for contactless three-dimensional (3D) electroanatomical integration in the EP laboratory. Prenatal monitoring of fetal well-being for early detection of cardiac arrhythmias and /or cardiomyopathy is rapidly growing and fetal MCG recording is surely another major clinical application for MMCG. 3D multimodal integration of MMCG with other imaging methods (magnetic resonance imaging, computer tomography, echocardiography and myocardial scintigraphy) and the development and availability of more advanced but user-friendly technology are major challenges to provide clinicians with the ultimate equipment for clinical MMCG. As clinical applications of MMCG have been recently reviewed [1], only most recent trends and advances on the above mentioned applications are summarized in this paper.