Feasibility of simultaneous multichannel magnetocardiographic mapping, multiple monophasic action potential recording and laser photocoagulation of isolated and perfused rabbit ventricular myocardium

Abstract Background Multichannel magnetocardiographic mapping (MCG) has been validated as an accurate non-invasive method for 3D localization of arrhythmogenic substrates suitable ablation treatment and intracardiac electrophysiology catheters (1,2). High resolution (HR) MCG-guided multiple simultaneous monophasic action potential (multi-MAP) recording pacing with a single patented amagnetic catheter (AC) detects local mechanisms (3). Laser photocoagulation (LP) providing more controlled homogeneous myocardial lesions (4), may be alternative to radiofrequency (RF) ablation, without unwanted electromagnetic noise effect during real-time MCG. Purpose This study aimed experimentally test the feasibility multi-MAP LP guided by Methods An unshielded 36 channels SQUID system (sensitivity 30 fT/Hz1/2, at 1 Hz) (CMI, USA) was used Langendorff-perfused isolated rabbit heart MCG (Figure 1A). Four epicardial MAPs were simultaneously recorded (inter MAP distance: mm) AC (bandpass: DC-500 Hz; sampling frequency: 2 kHz) (GE-Prucka Cardiolab). performed NdYAG laser (Dornier Medilas 5100) safe myocardium (5). The carried out according NIH guidelines animal care use. Results imaging ventricular magnetic field distribution inverse source dipole model are shown in Figure 1B. difference morphology HR signals compatible anisotropy 1C). With appropriate cooling optic fiber-tissue interface, no damage induced LP, whereas deeper well defined intramural appreciable, different size function energy delivered 1D). Multi-MAP not significantly disturbed LP. Keeping unit least 5 meters away from sensors, artifacts observed Conclusion MCG, well-defined feasible on heart, major interferences, catheterization laboratory. technological developments, single-catheter focal is foreseen possible minimally invasive current interventional approaches. Funding Acknowledgement Type funding sources: None.