Dataset: Successful caudal vena cava and pulmonary vein isolation in healthy horses using 3D electro-anatomical mapping and a contact force-guided abaltion system

Background: Recently, treatment of equine atrial tachycardia by three-dimensional electro-anatomical mapping (3D EAM) and radiofrequency catheter ablation (RFCA) has been described. Myocardial sleeves in the caudal vena cava and pulmonary veins are a potential trigger for initiation and perpetuation of atrial tachycardia and atrial fibrillation in the horse. Isolation of these myocardial sleeves by RFCA may be an effective treatment for these arrhythmias.Objectives: To describe the feasibility of 3D EAM and RFCA to isolate caudal vena cava and pulmonary veins in adult horses using 3D mapping and a contact force (CF)-guided ablation system.Study Design: In vivo experiment.Methods: 3D EAM and RFCA was performed in five horses without cardiovascular disease under general anaesthesia, using the CF-guided system CARTO®3. Point-by-point RFCA aimed for isolation of caudal vena cava and pulmonary veins. Radiofrequency energy was delivered in power-controlled mode with a target power of 45 W, CF between 10-15 g and 30 ml/min irrigation rate, until an ablation-index of 450-500 was reached.Results: In the right atrium, myocardial sleeves of the caudal vena cava were isolated (n=5). In the left atrium, isolation of ostium II (n=3), ostium III (n=1) and ostium I, II and III en bloc (n=1) was performed. Successful isolation was confirmed by entrance and exit block.Main limitations: Horses were euthanized at the end of the procedure, so long term effects such as potential reconnection of isolated veins could not be studied.Conclusions: This is the first description of 3D EAM and RFCA with CARTO® 3 in horses, thereby showing the technical feasibility and successful caudal vena cava and pulmonary vein isolation. CF measurement allowed monitoring of catheter-tissue contact, resulting in efficient acute lesion creation as confirmed by entrance and exit block. This is a promising treatment for cardiac arrhythmias in horses.

背景：近年来，已有研究报道采用三维电解剖标测（three-dimensional electro-anatomical mapping, 3D EAM）与射频导管消融（radiofrequency catheter ablation, RFCA）治疗马心房心动过速的相关方案。后腔静脉与肺静脉处的心肌袖，是引发马心房心动过速与心房颤动并使其持续存在的潜在诱因。通过RFCA隔离此类心肌袖，或可成为治疗这类心律失常的有效手段。
研究目的：探讨采用三维标测系统与接触力（contact force, CF）引导消融系统，对成年马的后腔静脉与肺静脉进行隔离的3D EAM及RFCA技术的可行性。
研究设计：体内实验研究。
研究方法：选取5只无心血管疾病的成年马，在全身麻醉状态下，采用CF引导的CARTO®3系统开展3D EAM与RFCA操作。以逐点消融的方式针对后腔静脉与肺静脉进行隔离。射频能量采用功率控制模式输出，目标功率为45 W，接触力维持在10~15 g，灌注速率为30 ml/min，直至消融指数（ablation-index）达到450~500。
研究结果：在5只受试马的右心房中，均成功实现后腔静脉心肌袖的隔离（n=5）。在左心房中，分别完成了肺静脉口II型（n=3）、肺静脉口III型（n=1）以及肺静脉口I、II、III型一并隔离（n=1）的操作。隔离成功与否通过传入阻滞与传出阻滞进行验证。
主要局限性：本实验在操作结束后对所有受试马实施了安乐死，因此无法评估隔离静脉后续可能出现的再连通等长期效应。
结论：本研究首次报道了在马中采用CARTO®3系统开展3D EAM与RFCA的操作，证实该技术可成功实现后腔静脉与肺静脉隔离，具备临床应用的技术可行性。接触力监测可实时监控导管与组织的贴合状态，结合传入与传出阻滞的验证结果，可确保急性期消融损伤的高效形成。该技术为马类心律失常的治疗提供了极具前景的方案。