Rapid mapping and differentiation in ventricular outflow tract arrhythmia using non-contact mapping

Area of Science:

• Electrophysiology
• Cardiac Arrhythmia Mapping
• Minimally Invasive Cardiac Procedures

Background:

• Ventricular outflow tract arrhythmias (VOTAs) are treatable with catheter ablation.
• Differentiating VOTAs originating from the right ventricular outflow tract (RVOT) from other sites can be challenging, leading to prolonged procedures.
• Non-contact mapping (NCM) offers a potential solution for precise arrhythmia source localization.

Purpose of the Study:

• To identify distinct propagation pattern characteristics using NCM for VOTAs.
• To differentiate between RVOT and non-RVOT origins of VOTAs.
• To improve the efficiency and accuracy of VOTA ablation procedures.

Main Methods:

• Analysis of isopotential maps from virtual unipolar electrograms (VUEs) in 45 patients undergoing NCM-guided VOTA ablation.
• Assessment of mapping data for isopotential areas with an initial negative VUE of -1 mV.
• Comparison of propagation patterns between patients with RVOT and non-RVOT origins.

Main Results:

• Successful ablation was achieved in 34 patients (RVOT group) and 11 (non-RVOT group).
• The ratio of major/minor axis diameter of the isopotential area was significantly greater in the RVOT group (1.9 vs 1.3, P < 0.001).
• Propagation velocity was significantly slower in the RVOT group (2.2 vs 4.2 mm²/ms, P = 0.02).

Conclusions:

• VOTAs originating from the RVOT exhibit a more elliptical and slower spread compared to other sites.
• NCM-derived propagation patterns provide valuable information for VOTA ablation.
• Utilizing NCM can lead to more efficient and targeted VOTA ablation strategies.