Cardiac Surgery Unit, Department of Cardiac, Thoracic and Vascular Sciences, University of Padua, Padua, Italy.
Department of Statistical Sciences, University of Bologna, Bologna, Italy.
Eur J Cardiothorac Surg. 2018 Aug 1;54(2):273-280. doi: 10.1093/ejcts/ezy046.
Transapical off-pump mitral valve intervention with neochordae implantation is a novel, minimally invasive procedure for treatment of degenerative mitral valve regurgitation. The aim of this study was to apply control charts (CUSUM curves) to monitor the performance of NeoChord repair during the initial phase of its adoption.
The first 112 consecutive patients who underwent NeoChord repair at our institution between November 2013 and March 2016 were included in the analysis. Mitral Valve Academic Research Consortium criteria for 1-year patient success was utilized to determine failed procedures. Control charts had predetermined acceptable and unacceptable failure rates of 5% and 15%, respectively.
The actual incidence of 1-year-patient failure was 11% (12 of 112 cases), with a cluster of failures within the first 20 cases. The CUSUM analysis demonstrated an initial learning curve; however, the upper boundary (alarm line) was never crossed. The reassurance line was first crossed after 40 procedures and performance remained stable after 49 procedures.
NeoChord repair is a safe procedure, and the results are maintained through the 1-year follow-up. A relative high number of implants were required to overcome the learning curve at our institution due to the concurrent development of patient selection criteria and the technical refinement of the procedure. Future studies are needed to assess the evolution of the learning curve after the wide adoption of the procedure across European and North American centres.
经心尖不停跳二尖瓣修复术联合植入人工腱索是一种治疗退行性二尖瓣反流的新型微创方法。本研究旨在应用控制图（CUSUM 曲线）来监测 NeoChord 修复术在采用初期的表现。
我们分析了 2013 年 11 月至 2016 年 3 月期间在我院接受 NeoChord 修复术的前 112 例连续患者。采用二尖瓣学术研究联合会（Mitral Valve Academic Research Consortium）制定的 1 年患者成功率标准来确定手术失败。控制图预先设定了可接受和不可接受的失败率分别为 5%和 15%。
1 年患者失败的实际发生率为 11%（112 例中有 12 例），前 20 例中有失败病例聚集。CUSUM 分析显示出初始学习曲线；然而，上限（警报线）从未超过。在 40 例手术后首次越过了保证线，在 49 例手术后，性能保持稳定。
NeoChord 修复术是一种安全的手术，在 1 年的随访中结果得以维持。由于患者选择标准的同时发展和手术技术的不断改进，我们医院需要植入相对较多的植入物来克服学习曲线。未来的研究需要评估该手术在欧洲和北美中心广泛采用后的学习曲线演变。
