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Background: CARTONET® enables automatic ablation site classification and reconnection site prediction using machine learning. However, the accuracy of the site classification model and trends of the site prediction model for potential reconnection sites are uncertain. Methods: We studied a total of 396 cases. About 313 patients underwent pulmonary vein isolation (PVI), including a cavotricuspid isthmus (CTI) ablation (PVI group) and 83 underwent PVI and additional ablation (i.e., box isolation) (PVI+ group). We investigated the sensitivity and positive predictive value (PPV) for automatic site classification in the total cohort and compared these metrics for PV lesions versus non‐PV lesions. The distribution of potential reconnection sites and confidence level for each site was also investigated. Results: A total of 29,422 points were analyzed (PV lesions [n = 22 418], non‐PV lesions [n = 7004]). The sensitivity and PPV of the total cohort were 71.4% and 84.6%, respectively. The sensitivity and PPV of PV lesions were significantly higher than those of non‐PV lesions (PV lesions vs. non‐PV lesions, %; sensitivity, 75.3 vs. 67.5, p <.05; PPV, 91.2 vs. 67.9, p <.05). CTI and superior vena cava could not be recognized or analyzed. In the potential reconnection prediction model, the incidence of potential reconnections was highest in the posterior, while the confidence was the highest in the roof. Conclusion: The automatic site classification of the CARTONET®R12.1 model demonstrates relatively high accuracy in pulmonary veins excluding the carina. The prediction of potential reconnection sites feature tends to anticipate areas with poor catheter stability as reconnection sites. [ABSTRACT FROM AUTHOR]

Introduction: Transvenous lead extractions (TLEs) for cardiac implantable electronic device complications often encounter difficulties with strong adhesions to the myocardium or vessels. In this report, we introduce a novel "Four‐Stage Rocket" technique for effective TLE in cases where conventional methods fail. Methods and Results: Two challenging cases where conventional TLE methods failed were treated using a combination of four devices: Needle's Eye Snare, Agilis NxT Steerable Introducer, GlideLight Laser sheath, and GORE® DrySeal Flex Introducer sheath, employed via the inferior vena cava. The "Four‐Stage Rocket" technique successfully detached firmly adhered leads near the tricuspid valve annulus, where the traditional superior vena cava approach was inadequate. Conclusion: The "Four‐Stage Rocket" technique offers a potential alternative in complex TLE cases, aligning the laser direction with the adhesion detachment and reducing the tissue damage risk. [ABSTRACT FROM AUTHOR]

Background: A novel irrigation catheter (QDOT MICRO™) has been introduced, which enables a surface temperature‐controlled ablation combined with tip cooling. However, the detailed description of its complex behavior and effect on the incidence of pops and lesion formation remains elusive. This study aimed to systematically investigate the ablation characteristics, feedback behavior, and incidence of steam pops in a simplified ex vivo swine model. Methods: Using swine ventricular tissue perfused with saline at 37°C, we systematically created lesions with 4×3 combinations of the wattage (20, 30, 40, and 50 W) and contact force (CF, 10, 30, and 50 g). Ablation was continued for either 120 s or until a steam pop occurred and repeated 10 times with each setting. The lesion geometry, ablation index, feedback dynamics, and conditions underlying the steam pops were measured and analyzed. Results: Steam pops occurred particularly frequently in combinations of a low CF and high power (10 g vs. 30 g+50 g [p <.0001]; 40 W+50 W vs. 20 W+30 W [p <.0001]). Failure to activate a feedback process was associated with a 5.1 times higher incidence of steam pops (21/109 vs.11/11, [95% CI 3.499–7.716], p <.0001). The wattage feedback was particularly evident with a high CF (30 and 50 g) and high initial wattage (40 and 50 W). The average delivered wattage at 27 W predicted the occurrence of steam pops. Conclusion: The temperature‐controlled ablation with the QDOT MICRO™ demonstrated a complex feedback behavior, which contributed to a reduced incidence of steam pops and prolonged lead time to the pops. [ABSTRACT FROM AUTHOR]

A novel plastic injection mold design for a product with a deep arc-hole based on the kinematic analysis is proposed. To move the wide angle arc-core, a hybrid mechanism combining a slider-crank and a swing cam is designed. The force transmission coefficient of the slider-crank and the pressure angle of the swing cam are used to evaluate the dimensions of the mechanism. The motion of the designed mechanism was confirmed by using a prototype made with a 3D printer. [ABSTRACT FROM AUTHOR]