Feld Yair, Dubi Shay, Reisner Yotam, Schwammenthal Ehud, Shofti Rona, Pinhasi Alon, Carasso Shemy, Elami Amir
Rambam Medical Center, Haifa, Israel.
Acute Card Care. 2011 Dec;13(4):232-42. doi: 10.3109/17482941.2011.634012.
We hypothesized that attachment of elastic coil to the left ventricular (LV) wall, capable of exerting outward forces may allow the transfer of energy from systole to diastole and improve diastolic function.
An extra-ventricular-device, composed of a series of elastic elements interposed between spiral screws attached to the epimyocardium of the LV free-wall was developed. The hemodynamic and mechanical effects of the device were tested using a computerized model, an in vitro model utilizing a computerized-controlled fluid pump, eight healthy sheep and 10 mini-pigs induced with diastolic dysfunction by renal wrapping. The computerized and in vitro models predicted a reduction of the LV diastolic pressure curve and partial normalization of the pressure-volume loop. The sheep study demonstrated preservation of animal's wellbeing including maintaining cardiac mechanical function with stable energy transfer from systole to diastole throughout the 6 months follow-up. The mini-pigs study showed an increase in the early diastolic to systolic strain-rate ratio in the mid-endocardial level (23 ± 10%, P = 0.008) and an increase in early apical reverse rotation rate of 50% (P = 0.016 compared to control).
This study presents a novel concept of using a mechanical device to transfer energy from systole to diastole, potentially enhancing diastolic function.
我们假设,将弹性线圈附着于左心室(LV)壁,使其能够施加向外的力,可能会实现从收缩期到舒张期的能量传递,并改善舒张功能。
研发了一种心室外部装置,该装置由一系列弹性元件组成,这些元件置于附着于左心室游离壁心外膜的螺旋螺钉之间。使用计算机模型、利用计算机控制流体泵的体外模型、八只健康绵羊以及十只通过肾包膜诱导舒张功能障碍的小型猪,对该装置的血流动力学和机械效应进行了测试。计算机模型和体外模型预测左心室舒张压曲线降低,压力-容积环部分恢复正常。绵羊研究表明,在整个6个月的随访期间,动物的健康状况得以维持,包括心脏机械功能得以保持,收缩期到舒张期的能量传递稳定。小型猪研究显示,心内膜中层早期舒张期与收缩期应变率比值增加(23±10%,P = 0.008),心尖早期反向旋转速率增加50%(与对照组相比,P = 0.016)。
本研究提出了一种利用机械装置将能量从收缩期传递到舒张期的新概念,这可能会增强舒张功能。