Factors affecting basket catheter detection of real and phantom rotors in the atria: A computational study

Figures

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  Fig 1. Action potentials (APs) and their corresponding atrial regions. A) AP produced by each variation of the CRN model in control (top) and chronic AF (bottom) conditions. B) Atrial regions to which each cell model was assigned.

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  Fig 2. Positions of the 64-pole basket mapping catheter in the RA. A-C) SVC, CT and CS position (first and second column) and electrode-endocardium distance maps for the 64 electrodes in each position (third column). SVC and IVC: superior and inferior vena cava; LA and RA: left and right atrium; LPV and RPV: left and right pulmonary veins; TV: tricuspid valve; LAA and RAA: left and right atrial appendage.

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  Fig 3. Electrical propagation and phase maps. A) Snapshot of the simulated transmembrane potential (Vm) in the 3D atrial model at t = 5125 ms. CT rotor (white arrow), RWE (dashed white arrow), CS stimuli wave front (orange dashed arrows), wave fronts in the LA (dotted white arrows) and lines of collision (black lines). B) Snapshot of the EGMs phase maps, computed on the endocardium-blood interface after filtering, at t = 5125 ms. C) EGM traces corresponding to points 1–10 in panel A. Blue circles on the traces show the closest activation times to t = 5125 ms. Green and blue arrows superimposed over the EGMs demonstrate the sequential activation times of the tissue at points 1–5 (CT rotor) and 6–10 (RWE), respectively. SVC and IVC: superior and inferior vena cava; RPV and LPV: right and left pulmonary veins; RA and LA: right and left atrium; TV: tricuspid valve; CS: coronary sinus; CT rotor: rotor on the crista terminalis; RWE: rotor wave extension.

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  Fig 4. RA and the CT rotor meandering area in relationship with the near and far basket electrodes in the SVC, CT and CS positions. A) Meandering area of the CT rotor (black) and region of the endocardium located at a distance d ≤ 0.5 cm (red) and 0.5 < d ≤ 1.0 cm (green) from at least one electrode for the SVC (top), CT (middle) and CS (bottom) positions. Panels illustrating the positions of the basket inside the RA have been also included on the left side for clarity. Right side column depicts EGM traces from electrodes set at d ≤ 0.5 cm (red) and 0.5 < d ≤ 1.0 cm (green) for the SVC, CT and CS positions. B) RA coverage by the basket computed as the ratio between the section of the endocardium at a distance d ≤ 0.5 cm (red) and 0.5 < d ≤ 1.0 cm (green) from at least one electrode over the whole interface for the three basket positions. C) Coverage of the CT rotor meandering area computed as the ratio between the section of the meandering area overlapped to the RA coverage over the whole meandering area. SVC and IVC: superior and inferior vena cava; LA and RA: left and right atrium; RPV: right pulmonary veins; TVR: tricuspid valve ring; CS: coronary sinus; RAA: right atrial appendage.

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  Fig 5. Basket mapping for the SVC position. A) Views of the location of the basket in the RA (top row), snapshots of the phase maps in the endocardium-blood interface (middle row) and of the phase map computed from the basket’s recordings (bottom row) at t = 10000 ms. PSs of the whole simulation were depicted in white over the phase maps (middle and bottom row). The black curves on the basket’s phase map correspond to the SVC, IVC and TVR orifices. CT rotor (white arrow): rotor on the crista terminalis; RWE (white dashed arrow): rotor wave extension; IMPSs (black arrows): imaginary phase singularities; FIPSs (grey arrow): false interpolation phase singularities. B) Selection of points (P1, P2 and P3) belonging to the CT rotor meandering area (top row); snapshots of the basket phase map when the CT rotor was moving through the points P1-P3 (second to bottom row). Green points denote the electrodes surrounding the CT rotor and red points denote the electrodes surrounding the IMPSs. C) EGMs at electrodes detecting the CT rotor (C3, B2, B3), IMPSs (F4, F5, G4), RWE (C7, B8, B7) and FIPS (C8, C7, B8). Blue circles on the plot of the EGMs indicate the activation time closest to t = 10000 ms.…

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  Fig 6. Basket mapping for the CT position. The layout of this Fig is the same as in Fig 5.

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  Fig 7. Basket mapping for the CS position. The layout of this Fig is the same as in Fig 5.

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  Fig 8. Effect of the far-field sources. Maps for the endocardial and CT positioned basket were generated for 3 different distributions of sources. All maps are shown at t = 4935 ms. A) Sources include the whole RA and LA (A1), B) sources include tissue only encompassing the CT rotor and the RWE at the IVC (B1), and C) sources include only tissue encompassing the CT rotor (C1). A2, B2 and C2: Voltage maps of the EGMs computed on the endocardium-blood interface corresponding to the whole (A2) and limited atrial sources (B2 and C2). Blue arrows (A2) indicate edges of EGM wave propagating around the TV. Hatched blue arrows in B2 indicate that once the sources are removed from the TV region, no significant voltage gradients are visible in that location. A3, B3 and C3: Phase maps computed on the EGMs maps from the endocardium-blood interface. In the whole sources map (A1), no PS is visible at the moment of this analysis (yellow arrow indicates a short living PS at earlier time). Orange arrows (B3) indicate PS outside of the sources region which is therefore an IMPS resulting from far field sources. Green arrow (C3) indicates a dramatic shift of the RWE into a region outside of the sources…

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  Fig 9. Effect of EGMs interpolation in the phase maps. 2D projection of the baskets (A) and phase maps for the SVC (B), CT (C) and CS (D) positions with a density of electrodes of 4×6 (left), 8×8 (middle) and 16×16 (right). IMPSs: imaginary phase singularities; FIPSs: false interpolation phase singularities; CT rotor: rotor along the crista terminalis; RWE: rotor wave extension.