Silicon based ultrasonic microprobes for cardiac signal recording

3D mapping of physioelectrical activities in in-vitro cardiac tissues is highly desirable for the study of the mechanism and development of cardiac arrhythmias. Important information can be obtained for prediction and prevention of arrhythmias, especially ventricular arrhythmia - one of the leading causes of mortality in the United States. In this paper, we present ultrasonically actuated silicon microprobes to reduce insertion force and minimize tissue damage. Probe tips with multiple recording sites were successfully inserted into canine heart tissue and cardiac signals in two dimensions were recorded. These recordings provide information for reconstruction of the physioelectrical wave propagation within heart tissue which is important in the study of the mechanism and development of cardiac arrhythmias.