Clinical Electrophysiology -> Ventricular Arrhythmias -> Mapping & Imaging D-PO06 - Poster Session VI (ID 26) Poster

D-PO06-053 - Mini, µ And Conventional Electrodes: An In-vivo Electrophysiology And Ex-vivo Histology Head-to-head Comparison (ID 685)


Background: Multiple variables impact BV mapping. Electrode size, spacing and directional dependency are of interest with the development of mini- and µ-electrode catheters
Objective: Compare voltages generated using QDot and Pentaray with the gold standard for scar identification: histology
Methods: The LV endocardium of 9 swine with early reperfusion infarctions were mapped with a QDot catheter (3 µ-electrodes in the distal tip), contact force >9g, angle of incidence <30°. The LV was re-mapped with Pentaray catheter (BVp). Data was exported and processed in ParaView (Kitware Inc., New York). For each QDot point, the highest amplitude BVP within 5mm was analyzed. At 53 locations, 10mm wide transmural biopsies were taken and the amount of viable myocardium (VM) quantified
Results: In 2322 QDot points the conventional BV (BVC) was 1.9±1.3mV. The largest of the 3 BVµ averaged 4.8±3.1mV. The difference in µ amplitudes (BVµMax-BVµMin) was 2.3±2mV. A positive relationship, with significant spread, was seen between BVµMax and BVµMin (Fig A). When BVC was compared to the BVµMax collected simultaneously, a positive relationship was seen with more spread (Fig B). 1044 QDot points were matched to BVP points. The relationship between BVµMax and BVP was positive but with poor correlation (Fig C). While all voltages increase, the same increase in VM results in the largest absolute change in BVµMax with the best correlation (fig D)
Conclusion: Wavefront propagation direction plays a significant role (fig E). Using a QDot catheter, simultaneous recording with 3 µ-electrodes increases the chance that one pair will align with the wavefront allowing for accurate detection of subendocardial viable myocardium.