The looped heart does not save energy by maintaining the momentum of blood flowing in the ventricle.

@article{Watanabe2008TheLH,
  title={The looped heart does not save energy by maintaining the momentum of blood flowing in the ventricle.},
  author={Hiroshi Watanabe and Seiryo Sugiura and Toshiaki Hisada},
  journal={American journal of physiology. Heart and circulatory physiology},
  year={2008},
  volume={294 5},
  pages={
          H2191-6
        }
}
Previous studies suggested that the reconstruction or maintenance of physiological blood flow paths in the heart is important to obtain a good outcome following cardiac surgery, but this concept has no established theoretical foundation. We developed a multiscale, multiphysics heart simulator, based on the finite element method, and compared the hemodynamics of ventricles with physiological and nonphysiological flow paths. We found that the physiological flow path did not have an energy-saving… 

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