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Abstract

We have designed a new type of aortic cannula for extracorporeal circulation which we hypothesize has superior haemodynamic characteristics compared with existing types. The aim of the study was to perform a quantitative evaluation of the haemodynamic performance of commercially available aortic cannulas against our new design. Six existing cannulas and two self-designed, modified DLP cannulas were investigated. Pressure drop, peak velocity and wall thickness were obtained from in vitro experiments. Pressure drop and turbulent stresses were obtained by in vivo experiments. At 5 L/min the pressure drops of the new design were 18 - 25 mmHg in vitro and 20 mmHg in vivo compared with 25 - 92 mmHg in vitro and 28 - 90 mmHg in vivo for the six commercially available cannulas. Turbulent stresses of the new design varied between 25 and 50 N/m² in vivo compared with 125 - 500N/m². Both in vivo and in vitro results showed a clear haemodynamic superiority of the new cannula-tip design compared with all existing types.

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References

Groom RC , Hill AG , Kuban B et al. Aortic cannula velocimetry . Perfusion 1995; 10: 183-188 .

Muehrcke DD , Cornhill JF , Thomas JD et al. Flow characteristics of aortic cannula . J Card Surg 1995; 10: 514-519 .

Joubert-Huebner E , Gerdes A , Sievers HH. An in vitro evaluation of a new cannula tip design compared with two clinically established cannula-tip designs regarding aortic arch vessel perfusion characteristics . Perfusion 2000; 15: 69-76 .

Ringgaard S , Madsen T , Pedersen EM et al. Quantitative evaluation of flow patterns in perfusion cannula by a new magnetic resonance imaging method . Perfusion 1997; 12: 411-416 .

Nerem RM , Seed WA. An in vivo study of aortic flow disturbances . Cardiovasc Res 1972; 6: 1-14 .

Tesar V. Basic fluid mechanics. Hypertext textbook for CVUT engineers. Prague: Czech Technical University in Praha , 1997.

Munson BR , Young DF , Okiishi TH. Fundamentals of fluid mechanics, third edition. New York, NY: John Wiley & Sons, Inc. , 1998.

Hinze JO. Turbulence. New York, NY: McGraw-Hill , 1975.

Hasenkam JM , Pedersen EM , Østergaard JH et al. Velocity fields and turbulent stresses downstream of biological and mechanical aortic valve prostheses implanted in pigs . Cardiovasc Res 1988; 22: 472-483 .

10.

Nygaard H , Paulsen PK , Hasenkam JM , Pedersen EM , Rovsing PE. Turbulent stresses downstream of three mechanical aortic valve prostheses in human beings . J Thorac Cardiovasc Surg 1994; 107: 438-446 .

11.

Nygaard H , Hasenkam JM , Pedersen EM et al. A new perivascular multi-element pulsed Doppler ultrasound system for in vivo studies of velocity fields and turbulent stresses in large vessels . Med Biol Eng Comput 1994; 32: 55-62 .

12.

Scheidegger MB , Maier SE , Bösiger P. FID-acquired-echoes (FAcE): a short echo time imaging method for flow artifact suppression . Magn Reson Imaging 1991; 9: 517-524 .

Quantitative haemodynamic evaluation of aortic cannulas

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