Arrhythmia source localization from intravenous and transthoracic catheter measurements

Catheter-based epicardial mapping is possible with two access methods: transthoracic access and transvenous access. Transthoracic access requires lengthy sequential mapping procedures and stable arrhythmias. Transvenous access uses the multielectrode (4-to-20 electrodes) catheters placed in the coronary veins, however, leaves most of the epicardium inaccessible to direct measurement. The aim of this present study is to demonstrate that the reconstruction of the high-resolution maps using sparse measurements from different sites on the epicardium and on the multielectrode catheters is possible with a reasonably high accuracy in terms of locating the origin of the ventricular arrhythmia. In this study we investigated strategies for recordings of transvenous and transthoracic epicardial mapping catheters, alone and in combination. For this purpose, we first examined the problem of best sampling resolution using transthoracic mapping catheters and secondly studied the feasibility of the combined usage of both mapping approaches. We evaluated two prediction methods; the Laplacian interpolation and statistical estimation. We performed 14 dog experiments to create a high-resolution epicardial potential map database. We found that 2 cm sampling resolution is quite feasible. The combined usage of transvenous and transthoracic mapping approaches improved the accuracy significantly. The results of this study encourage further investigation and provide adequate evidence for the clinical applicability of such an epicardial mapping method based on catheters.