Tomos E Walters1, Geoffrey Lee1, Steven Spence2, Jonathan M Kalman3. 1. Department of Cardiology, Royal Melbourne Hospital, Melbourne, Australia; Department of Medicine, University of Melbourne, Melbourne, Australia. 2. Department of Cardiology, Royal Melbourne Hospital, Melbourne, Australia. 3. Department of Cardiology, Royal Melbourne Hospital, Melbourne, Australia; Department of Medicine, University of Melbourne, Melbourne, Australia. Electronic address: jon.kalman@mh.org.au.
Abstract
BACKGROUND: Mechanisms sustaining human persistent atrial fibrillation (AF) remain debated, with significant differences between high-density epicardial and global endocardial mapping studies. A key difference is the density of recording electrodes. OBJECTIVE: We aimed to determine the differences in the prevalence of different atrial activation patterns, and specifically in the prevalence of rotational activations, with varying densities of bipolar electrodes. METHODS: Epicardial mapping was performed in 10 patients undergoing cardiac surgery, with bipolar electrograms recorded using a triangular plaque (6.75 cm(2) area; 117 bipoles; 2.5-mm inter-bipole spacing) applied to the left atrial posterior wall or right atrial free wall. Dynamic wavefront mapping based on the timing of atrial electrograms was applied to 2 discrete 10-second AF segments. The spacing between bipolar electrode locations was increased from 2.5 × 3.5 mm in the horizontal and oblique directions to 5.0 × 3.5, 5.0 × 7.1, and 7.5 × 10.6 mm, with wavefront mapping repeated at each density. RESULTS: As density reduced, there was a significant change in relative proportions of the various activation patterns (F=3.69; P < .001). Simple broad wavefront activations became more prevalent (20% ± 8% to 54% ± 8%; P < .05) and complex patterns became less prevalent (48% ± 8% to 9% ± 8%; P < .05) with reducing density. The prevalence of rotational activity declined with bipole density, from median 5.0% (range 0.9%-12.1%) to 0% (range 0%-1.5%) (P = .03). The largest change occurred between inter-bipole spacings of 5.0 × 3.5 and 5.0 × 7.1 mm. CONCLUSION: Apparent activation patterns in persistent AF vary significantly with electrode density. Low density underestimates the prevalence of complex and rotational patterns. The largest difference occurs between an inter-bipole spacing of 5.0 × 3.5 and a spacing of 5.0 × 7.1 mm. This may have important implications for mapping technology design.
BACKGROUND: Mechanisms sustaining human persistent atrial fibrillation (AF) remain debated, with significant differences between high-density epicardial and global endocardial mapping studies. A key difference is the density of recording electrodes. OBJECTIVE: We aimed to determine the differences in the prevalence of different atrial activation patterns, and specifically in the prevalence of rotational activations, with varying densities of bipolar electrodes. METHODS: Epicardial mapping was performed in 10 patients undergoing cardiac surgery, with bipolar electrograms recorded using a triangular plaque (6.75 cm(2) area; 117 bipoles; 2.5-mm inter-bipole spacing) applied to the left atrial posterior wall or right atrial free wall. Dynamic wavefront mapping based on the timing of atrial electrograms was applied to 2 discrete 10-second AF segments. The spacing between bipolar electrode locations was increased from 2.5 × 3.5 mm in the horizontal and oblique directions to 5.0 × 3.5, 5.0 × 7.1, and 7.5 × 10.6 mm, with wavefront mapping repeated at each density. RESULTS: As density reduced, there was a significant change in relative proportions of the various activation patterns (F=3.69; P < .001). Simple broad wavefront activations became more prevalent (20% ± 8% to 54% ± 8%; P < .05) and complex patterns became less prevalent (48% ± 8% to 9% ± 8%; P < .05) with reducing density. The prevalence of rotational activity declined with bipole density, from median 5.0% (range 0.9%-12.1%) to 0% (range 0%-1.5%) (P = .03). The largest change occurred between inter-bipole spacings of 5.0 × 3.5 and 5.0 × 7.1 mm. CONCLUSION: Apparent activation patterns in persistent AF vary significantly with electrode density. Low density underestimates the prevalence of complex and rotational patterns. The largest difference occurs between an inter-bipole spacing of 5.0 × 3.5 and a spacing of 5.0 × 7.1 mm. This may have important implications for mapping technology design.
Authors: Amin Al-Ahmad; Bradley Knight; Wendy Tzou; Robert Schaller; Omar Yasin; Deepak Padmanabhan; Jason Zagrodzky; Mohammed Bassiouny; J David Burkhardt; G Joseph Gallinghouse; Moussa Mansour; Christopher McLeod; Andrea Natale Journal: J Cardiovasc Electrophysiol Date: 2021-10-01 Impact factor: 2.942
Authors: Jorge G Quintanilla; José Manuel Alfonso-Almazán; Nicasio Pérez-Castellano; Sandeep V Pandit; José Jalife; Julián Pérez-Villacastín; David Filgueiras-Rama Journal: Circ Res Date: 2019-08-01 Impact factor: 17.367