Skov Søren Nielsen, Røpcke Diana Mathilde, Tjørnild Marcell Juan, Ilkjær Christine, Rasmussen Jonas, Nygaard Hans, Jensen Morten Olgaard, Nielsen Sten Lyager
Department of Cardiothoracic and Vascular Surgery, Aarhus University Hospital, Aarhus, Denmark.
Department of Clinical Medicine, Aarhus University Hospital, Aarhus, Denmark.
Interact Cardiovasc Thorac Surg. 2017 May 1;24(5):683-690. doi: 10.1093/icvts/ivx004.
To characterize the remodelling effects and deformational forces of normosized rigid, semirigid and flexible mitral annuloplasty rings after implantation in healthy pigs.
Measurements were performed in vivo with 80-kg porcine animals. Twenty-eight animals were randomized into a no ring group, a flexible ring group (Duran AnCore Ring, Medtronic, Minneapolis, MN, USA), a rigid ring group (Carpentier-Edwards Classic annuloplasty ring, Edwards Lifesciences, Irvine, CA, USA) and a semirigid ring group (Carpentier-Edwards Physio I annuloplasty ring, Edwards Lifesciences). Sonomicrometry crystals were implanted together with an annuloplasty ring and a dedicated mitral annular force transducer. The mitral annuloplasty rings were compared with respect to annular geometry and mitral annular forces.
Cyclic changes in the mitral annulus (MA) circumference were significantly lower for all ring groups (flexible: 7 ± 3 mm, semirigid: 4 ± 2 mm and rigid: 2 ± 1 mm) compared to the no ring group (11 ± 5 mm), implying the remodelling capacity of all annuloplasty rings. The cyclic change of the MA area and the septa-lateral and inter-commissural distances were equal in the semirigid and rigid ring groups and significantly lower compared to the no ring and flexible ring groups, suggesting a stronger and equal remodelling effect in the semirigid and rigid ring groups. Forces measured in the transducer reflected the remodelling capacity of the annuloplasty rings and were in general lower for the semirigid and rigid ring groups compared to the no ring and flexible ring groups. Especially the forces in the inter-commissural direction were significantly reduced for the semirigid and rigid ring groups (semi-rigid: 1.4 ± 0.8 N, rigid: 1.2 ± 0.8 N) compared to the no ring and flexible ring groups (no ring: 3.0 ± 1.1 N, flexible: 3.4 ± 1.6 N).
This study is the first to describe different remodelling effects and deformational forces of normosized mitral annuloplasty rings in vivo . Insights into the relationship between the remodelling effects and the accumulated forces of different mitral annuloplasty rings may have implications for ring selections in an aetiology-based mitral valve repair strategy. We propose the application of such a biomechanical approach for quantitative comparison of mitral annuloplasty rings and for future innovations on a rational basis.
描述正常尺寸的刚性、半刚性和柔性二尖瓣成形环植入健康猪体内后的重塑效果和变形力。
对体重80千克的猪进行体内测量。28只动物被随机分为无环组、柔性环组（美国美敦力公司的杜兰AnCore环）、刚性环组（美国爱德华生命科学公司的卡彭蒂埃 - 爱德华兹经典二尖瓣成形环）和半刚性环组（美国爱德华生命科学公司的卡彭蒂埃 - 爱德华兹生理I型二尖瓣成形环）。将超声心动图晶体与二尖瓣成形环和专用的二尖瓣环力传感器一起植入。比较二尖瓣成形环在瓣环几何形状和二尖瓣环力方面的情况。
与无环组（11±5毫米）相比，所有环组（柔性：7±3毫米，半刚性：4±2毫米，刚性：2±1毫米）二尖瓣环（MA）周长的周期性变化均显著降低，这意味着所有二尖瓣成形环都具有重塑能力。半刚性和刚性环组中MA面积以及间隔 - 外侧和瓣叶间距离的周期性变化相等，且与无环组和柔性环组相比显著降低，表明半刚性和刚性环组具有更强且相等的重塑效果。传感器测量的力反映了二尖瓣成形环的重塑能力，总体而言，半刚性和刚性环组的力低于无环组和柔性环组。特别是与无环组和柔性环组（无环组：3.0±1.1牛，柔性：3.4±1.6牛）相比，半刚性和刚性环组在瓣叶间方向的力显著降低（半刚性：1.4±0.8牛，刚性：1.2±0.8牛）。
本研究首次描述了正常尺寸二尖瓣成形环在体内的不同重塑效果和变形力。深入了解不同二尖瓣成形环的重塑效果与累积力之间的关系，可能对基于病因的二尖瓣修复策略中的环选择具有启示意义。我们建议应用这种生物力学方法对二尖瓣成形环进行定量比较，并为未来基于合理依据的创新提供支持。
