Cryoballoon Ablation of the Left Common Pulmonary Vein Using a Size‐Adjustable Cryoballoon: A Comparative Study

Figures

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  FIGURE 1. Measurements of the left common pulmonary vein. Three‐dimensional images of the left atrium and pulmonary veins were obtained via contrast‐enhanced computed tomography. The left common pulmonary vein ostium was identified (black line), and the maximum (red solid line) and minimum (red dotted line) diameters of the ostium were measured. The ovality index was calculated using the following formula: 2 × (maximal diameter – minimal diameter)/(maximal diameter + minimal diameter).

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  FIGURE 2. Balloon size selection of the POLARx FIT. The first application of the POLARx FIT was performed with a 31‐mm cryoballoon in all 28 patients. Five of the eight patients who achieved complete occlusion completed the procedure after the first freezing; the remaining three patients underwent additional freezing. The balloon size for the subsequent procedures was determined at the discretion of the operator. Among the 23 patients who underwent second freezing, a 28‐mm cryoballoon was used for 14 (60.9%) patients; a 31‐mm cryoballoon was used in 9 (39.1%) patients; and 13 (56.5%) patients ended freezing after the second freezing. Thereafter, a 28‐mm cryoballoon was used for 6 (60%) patients; a 31‐mm cryoballoon was used for 4 (40%) patients for the third freezing; a 28‐mm cryoballoon was used for 2 (40%) patients; and a 31‐mm cryoballoon was used for 3 (60%) patients for the fourth freezing.

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  FIGURE 3. One‐year arrhythmia‐free survival rate. The 1‐year arrhythmia‐free survival rate of all patients of POLARx was 81.8% (95% CI: 58.5%–92.8%) and that of the POLARx FIT was 78.7% (95% CI: 56.1%–90.6%), p = 0.92 (A). Among the paroxysmal atrial fibrillation (PAF) patients, the 1‐year arrhythmia‐free survival rate of the POLARx was 86.7% (95% CI: 56.4%–96.5%) and that of the POLARx FIT was 85.1% (95% CI: 52.3%–96.1%). Among the non‐PAF patients, the 1‐year arrhythmia‐free survival rates of the POLARx were 71.4% (95% CI: 25.8%–92%) and that of the POLARx FIT was 70% (95% CI: 32.9%–89.2%) (B).