The value of microelectrodes and microbipolar electrograms in premature ventricular complex mapping and ablation: The...

Area of Science:

• Cardiology
• Electrophysiology
• Medical Devices

Background:

• Catheter ablation is a key treatment for premature ventricular contractions (PVCs).
• Traditional mapping uses bipolar (bip-EGMs) and unipolar electrograms (uni-EGMs).
• Novel catheters with microbipolar electrodes (micro-EGMs) are now available.

Purpose of the Study:

• To evaluate the efficacy of micro-EGMs for mapping PVCs.
• To determine if micro-EGMs can differentiate superficial from intramural PVC origins.

Main Methods:

• A multicenter retrospective study of 81 patients undergoing PVC ablation with QDOT catheters.
• Patients were categorized by PVC origin: superficial (51) or intramural (30).
• Bipolar, unipolar, and microbipolar electrograms were analyzed at successful ablation sites.

Main Results:

• Micro-EGMs preceded bip-EGMs and uni-EGMs in 90% of superficial PVC cases.
• A delay of >10 ms between bip-EGM and micro-EGM predicted the need for ablation in both RVOT and LVOT (Sensitivity 0.94, Specificity 0.75).
• Micro-EGMs demonstrated significantly higher initial deflection amplitude (2.8 mV vs. 1.5 mV, P=.025).

Conclusions:

• Micro-EGMs enhance PVC mapping accuracy, particularly for estimating lesion depth.
• Micro-EGMs show promise for precise local activation time annotation.
• These findings have significant implications for automated annotation in electroanatomic mapping systems.