Localization of ischemia during coronary angioplasty using body surface potential mapping and an electrocardiographic inverse solution

The authors describe a qualitative, in vivo validation of a solution to the inverse problem of cardiology using percutaneous transluminal coronary angioplasty as a model of transient ischemia in humans. Body surface potential mapping with 117 unipolar electrodes was used to collect torso potential distributions from patients with single-vessel coronary artery disease before, during, and after inflation of the balloon catheter. A boundary-element solution of the homogeneous inverse problem based on a realistic model of the human torso provided estimates of the epicardial potentials from which it was possible to locate regions of transient ischemia. These regions of estimated ischemia agreed well with those predicted on the basis of coronary angiograms and balloon placement