Data Sheet 2_Clinical feasibility study of transcatheter edge-to-edge mitral valve repair in dogs with the canine V-Clamp device.pdf

ObjectiveTo determine procedural feasibility, safety, and short-term efficacy in dogs with severe degenerative mitral regurgitation (MR) undergoing transcatheter edge-to-edge repair (TEER) with a canine-specific device.
DesignProspective, single-arm (uncontrolled), single-institution clinical feasibility study.
AnimalsFifty client-owned dogs with severe degenerative MR operated over a 28-month period.
MethodsTEER was performed using the canine mitral V-Clamp via a transapical approach using transesophageal echocardiographic and fluoroscopic guidance. Indices of MR severity were determined by echocardiography the day before and 2 to 3 days after the procedure.
ResultsProcedural feasibility was 96% based on delivery of at least one device in 48 of 50 dogs. There were no procedural deaths. Procedural safety was 96% based on survival to hospital discharge in 48 of 50 dogs. Euthanasia in 2 dogs prior to hospital discharge was due to damage of the mitral valve and worsened MR after the procedure. Device-related adverse event rate was 6.3% based on 3 events (single-leaflet device detachment, locking failure, locking failure with device embolization) in 59 implanted devices. All three events were nonfatal and successfully treated with a second device. Median regurgitant volume (mL/kg) decreased (p < 0.001) from 2.3 [1.9, 3.1] to 1.1 [0.3, 1.8]. Median effective regurgitant orifice area (cm2/m2) decreased (p < 0.001) from 0.60 [0.40, 0.80] to 0.25 [0.10, 0.50].
Conclusion and clinical importanceInitial feasibility results support continued development of TEER as a procedurally feasible, relatively low-risk, and low morbidity treatment for degenerative MR in dogs. Operator experience and case selection are likely to be important components of success of this technique. Evidence of short-term efficacy is promising but needs to be verified with longer-term follow up.

【研究目的】明确采用犬专用器械行经导管缘对缘修复术（transcatheter edge-to-edge repair, TEER）治疗重度退行性二尖瓣反流（degenerative mitral regurgitation, MR）患犬的操作可行性、安全性及短期疗效。
【研究设计】前瞻性单臂（非对照）单中心临床可行性研究。
【研究对象】28个月周期内收治的50例饲主饲养的重度退行性MR患犬。
【研究方法】采用经食管超声联合透视引导，经心尖入路植入犬用二尖瓣V型夹（canine mitral V-Clamp）完成TEER。分别于术前1日及术后2~3日通过超声心动图评估MR严重程度相关指标。
【研究结果】50只患犬中48只成功植入至少1枚器械，操作可行性达96%，无术中死亡病例。50只患犬中48只顺利出院，操作安全性达96%。2只患犬于出院前实施安乐死，原因为术中二尖瓣损伤及术后MR加重。共植入59枚器械，其中3例发生器械相关不良事件（单瓣叶器械脱落、锁合失败、锁合失败伴器械栓塞），不良事件发生率为6.3%。上述3起事件均未致死，且通过植入第二枚器械成功处置。反流容积中位数（mL/kg）从术前的2.3 [1.9, 3.1] 降至术后的1.1 [0.3, 1.8]（p < 0.001）；有效反流口面积中位数（cm²/m²）从术前的0.60 [0.40, 0.80] 降至术后的0.25 [0.10, 0.50]（p < 0.001）。
【结论与临床意义】本研究初步可行性结果证实，TEER用于犬退行性MR的治疗具备操作可行性，且风险较低、并发症发生率低，支持该技术的进一步研发。术者经验与病例筛选或许是该技术成功的关键要素。本研究的短期疗效证据颇具前景，但仍需通过长期随访验证。