Journal: ACS biomaterials science & engineering

Article Title: In Vitro/Ex Vivo Investigation of Modified Utah Electrode Array to Selectively Sense and Pace the Sub-Surface Cardiac His Bundle

doi: 10.1021/acsbiomaterials.0c00065

Figure Lengend Snippet: Electrograms recorded using an electrode of the UEA implanted at HB-region. (A, top) The Atrial, His-Bundle and Ventricular (V) activations are shown by the arrows (blue) and marked as A, HB and V respectively. (A, center) The spatial derivative highlighted the electrode’s local electrical activity by subtracting the surrounding electrode’s electrical signal from the central electrode’s electrical information. (A, bottom) The time derivative of the spatial derivative signal highlights the HB electrical activity (bottom). (B) pseudo-ECG while pacing through an electrode of the UEA. ‘P’ indicates the pacing artifact. T1=pace interval and T2=R-R interval. (B, top) Pacing HB at lower current utilizing an electrode from UEA, T1≠T2. (B, center) Pacing continued until HB captured, T1=T2. Inset shows that QRS complex while HB captured and is of similar morphology as the QRS of pseudo-ECG when HB is not captured. (B, bottom) UEA’s electrode is on working myocardium location beside HB-region. Instead of pacing HB, WM was paced and captured, T1=T2. The inset shows the QRS complex while WM is captured and the morphology is significantly different in comparison with QRS complex while HB is captured. QRS insets of HB and WM paced beats are of different shapes with durations of 32 ms and 40 ms, respectively. Electrograms recorded through 96 electrodes of UEA while implanted in HB-region are shown in Fig. 6.

Article Snippet: Utah electrode arrays (UEAs) were custom designed and fabricated at Blackrock Microsystems, Salt Lake City, UT.

Techniques: Activity Assay, Comparison