Identification of regions maintaining atrial fibrillation through cycle length and cycle length gradient mapping

Figures

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  FIGURE 1. The concept of each map. (A) CL map: Colors represent CL; (B) Short CL map: Red areas show short CLs. The minimum CL is indicated by a red circle; (C) CL‐gradient map: Colors represent CL‐gradient; (D) Definition of areas within the left atrium; (E) CL‐gradient concept: The color of the points represents the CL of each point. The CL‐gradient at the X mark is defined as the CL range within a 6 mm radius centered on the X mark in the red area. CL. cycle length; RPV, right pulmonary vein; LPV, left pulmonary vein; LAA left atrial appendage.

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  FIGURE 2. Violin plots illustrating results of CL and CL‐gradient measurements. (A) CL measurements; (B) CL‐gradient measurements. (C, D, E) The relationship among the CL‐range, maximum CL‐gradient, and the left atrial diameter. (F) an example of a large left atrium. (G) an example of a small left atrium. CL, cycle length; PA; posterior–anterior view; AP, anterior–posterior view.

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  FIGURE 3. The minimum CL site and the maximum CL‐gradient site (A) Violin plots illustrating the distance between the minimum CL site and the maximum CL‐gradient site; (B) Example of a short distance case of AF termination; (C) Example of a long‐distance case of AF termination. AF, atrial fibrillation; CL, cycle length.

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  FIGURE 4. Characteristics of CL‐gradient. (A) The distance from the minimum CL to the maximum CL‐gradient is plotted on the x‐axis, and the maximum CL‐gradient values are plotted on the y‐axis for all cases. Stars: Cases where AF terminated; circles: Cases where AF did not terminate; blue: Cases classified as single in the short CL map; purple: Cases classified as multiple. The red background area indicates the pattern of steep gradient near the minimum CL (SG‐MCL). (B) Short CL maps and CL‐gradient maps. Left: A case of SG‐MCL where AF terminated by right pulmonary vein isolation; right: A case of non‐SG‐MCL where AF did not terminate. AF, atrial fibrillation; CL, cycle length.

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  FIGURE 5. (A) Examples of short CL map. Left: Single type. Middle: Multiple type. Right: Single type. (B) Distribution of the minimum CL and characteristics of CL map. The minimum CL values for all cases are plotted for each area where the minimum CL was observed. Stars: Cases where AF terminated; circles: Cases where AF did not terminate; blue: Cases classified as single in the short CL map; purple: Cases classified as multiple. AF, atrial fibrillation; CL, cycle length; LAA, left atrial appendage; LPV, left pulmonary vein; RPV, right pulmonary vein.

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  FIGURE 6. Case presentation. CL maps were revised based on the point selection conducted in this study. Red tags indicate ablation points. In CARTOFINDER maps, green denotes focal activities, and blue represents rotational activations. Voltage maps were created during AF. (A) PVI was started from the LPV. As ablation progressed downward from the roof of the posterior wall, AF converted to sinus rhythm when the bottom of the LPV was ablated (the white arrow). (B) After the LPV isolation was completed, AF converted to peri‐mitral atrial tachycardia during ablation of the RPV bottom (the white arrow), despite the RPV isolation not being completed. AF, atrial fibrillation; CL, cycle length; LPV left pulmonary vein; PVI, pulmonary vein isolation; RPV right pulmonary vein.