Simultaneous Recording of Electrical and Panoramic Optical Mapping From Ex-vivo Isolated Rabbit Hearts: From Sinus Rhythm to Induced Arrhythmia

Cardiovascular diseases (CVDs) are the leading causes of death globally, responsible for approximately 52.86% of deaths in Brazil. CVDs modify the characteristics of excitation and electrical propagation of the heart, making electrophysiological tests essential for diagnosis. Current commercial equipment used for clinical evaluation of the substrate can distort the electrograms, resulting in an erroneous diagnosis. Ex-vivo animal models have been developed to characterize the cardiac substrate to improve commercial medical equipment. For this study, New Zealand isolated rabbit hearts were Langendorff perfused and the epicardial electrical activity was acquired simultaneously with a panoramic optical mapping (using the Di-4-ANBDQPQ Voltage-sensitive dye), and a contact electrical mapping setup under sinus rhythm, electrical pacing and during arrhythmia. Finally, the 3D reconstruction subsystem obtained images around the heart and generated a 3D heart. After 18 months of development, seven experiments were performed, signals were synchronized, and metrics such as local activation time were analyzed. This study is significant for improving current knowledge of complex arrhythmia mapping and, more importantly, correct sub-strate characterization to improve current rates of successful treatment.