Department of Adult Cardiac Surgery, Hôpital cardiologique Louis Pradel, Lyon Medical School, Bron, France; Univ Lyon, INSA-Lyon, LGEF (Lab of electrical engineering and ferroelectricity), Villeurbanne, France; Department of Cardiovascular Surgery, Mount Sinai Hospital, New York, NY.
Univ Lyon, INSA-Lyon, LGEF (Lab of electrical engineering and ferroelectricity), Villeurbanne, France.
J Thorac Cardiovasc Surg. 2019 Sep;158(3):746-755. doi: 10.1016/j.jtcvs.2018.10.029. Epub 2018 Oct 17.
Complex structure of mitral valve and its central position in the heart limit assessment of mitral function to standardized calculated parameters assessed using medical imaging (echocardiography). Novel techniques, which allow mitral valve repair (MVr) in a beating heart, offer the opportunity for innovative objective assessment in physiologic and pathologic conditions. We report, to our knowledge, the first data of real-time chordal tension measurement during a transapical neochordae implantation.
Seven patients with severe degenerative mitral regurgitation due to posterior prolapse underwent transapical MVr using the NeoChord DS 1000 (NeoChord Inc, Minneapolis, Minn). During prolapse correction, the tension applied on the neochordae was measured in addition to hemodynamic and echocardiographic parameters.
The traction applied on 1 chorda sustaining the P2 segment was measured at between 0.7 and 0.9 N, and oscillated with respiration. When several neochordae were set in tension, this initial tension was spread homogeneously on each chorda (mean sum of the amplitude of tension 0.98 ± 0.08 N). To achieve an optimal echocardiographic correction, a complementary synchronous traction on all chordae was required. During this adjustment, the sum of the tension decreased (mean 12 ± 2%; P = .018), suggesting that when normal physiology was restored, the valvular apparatus was in a low-stress state. This method allowed us to apply a precise and reproducible technique, leading to a good procedural success rate with a low morbidity and mortality rate.
The tension applied on chordae during transapical implantation of neochordae for degenerative mitral regurgitation can be measured, providing original data about the objective consequences of MVr on the mitral apparatus.
二尖瓣结构复杂，位于心脏中央，限制了使用医学影像学（超声心动图）评估二尖瓣功能的标准化计算参数。允许在心脏跳动时进行二尖瓣修复（MVr）的新技术为生理和病理条件下的创新客观评估提供了机会。我们报告了首例实时测量经心尖植入新腱索时腱索张力的数据。
7 例因后叶脱垂导致严重退行性二尖瓣反流的患者接受了经心尖 MVr，使用 NeoChord DS 1000（NeoChord Inc，明尼苏达州明尼阿波利斯）。在脱垂矫正过程中，除了血流动力学和超声心动图参数外，还测量了新腱索上施加的张力。
测量支撑 P2 段的 1 根腱索的牵引力在 0.7 至 0.9 N 之间，随呼吸而波动。当几根腱索同时拉紧时，初始张力会均匀分布在每根腱索上（张力幅度的平均值为 0.98±0.08 N）。为了实现最佳的超声心动图矫正，需要对所有腱索进行同步补偿牵引。在此调整过程中，张力总和减小（平均 12±2%，P=0.018），表明当恢复正常生理时，瓣膜装置处于低张状态。这种方法允许我们应用精确且可重复的技术，以低发病率和死亡率实现良好的手术成功率。
在经心尖植入新腱索治疗退行性二尖瓣反流时，可测量施加在腱索上的张力，为 MVr 对二尖瓣装置的客观后果提供了原始数据。
