Noninvasive characterisation of multiple ventricular events using electrocardiographic imaging

Area of Science:

• Cardiovascular Electrophysiology
• Computational Cardiology

Background:

• Detecting multiple ventricular activation sites is crucial for effective treatment of complex arrhythmias.
• Body surface electrocardiograms (ECGs) often lack the resolution to identify distinct, simultaneous ventricular events.

Purpose of the Study:

• To investigate the feasibility of using calculated epicardial potentials to detect multiple ventricular activation sites.
• To assess the minimum distance between dual ventricular events required for detection using reconstructed epicardial potentials.

Main Methods:

• Simulated ventricular activation sequences from nine different paired sites using a human ventricular myocardial model.
• Generated body surface ECGs from simulated sequences and reconstructed epicardial potentials.
• Defined dual event detection by identifying two distinct primary potential minima in reconstructed epicardial potentials.

Main Results:

• Dual ventricular events were detectable when separated by as little as 27 mm in the right ventricle and 23 mm in the left ventricle.
• Increased noise levels (15-50 microV) in simulated ECGs reduced the distinguishability of dual events.
• Reconstructed epicardial potentials provided clearer visual information of multiple ventricular events compared to body surface ECGs.

Conclusions:

• Calculated epicardial potentials offer valuable visual data for identifying multiple ventricular events.
• This technique can enhance mapping procedures, particularly in challenging radiofrequency ablation cases for accessory pathways.