Papillary Muscle Approximation Reduces Systolic Tethering Forces and Improves Mitral Valve Closure in the Repair of Functional Mitral Regurgitation

...actuating pump with a viscoelastic impedance (Superpump, Vivitro Labs, London, ON) was connected to the LV, and programmed to generate physiological left ventricular pressures. 0.9% saline was used as the working medium in this flow loop...