Time-resolved three-dimensional magnetic resonance velocity mapping of aortic flow in healthy volunteers and patients after valve-sparing aortic root replacement

J Thorac Cardiovasc Surg. 2005 Aug;130(2):456-63. doi: 10.1016/j.jtcvs.2004.08.056.


Objective: To provide more complete characterization of ascending aortic blood flow, including vortex formation behind the valve cusps, in healthy subjects and patients after valve-sparing aortic root replacement (David reimplantation).

Methods: Time-resolved 3-dimensional magnetic resonance imaging velocity mapping was performed to analyze pulsatile blood flow by using encoded 3-directional vector fields in the thoracic aortas of 10 volunteers and 12 patients after David reimplantation using a cylindrical tube graft (T. David I) and two versions of neosinus recreation (T. David-V and T. David-V-S mod ). Aortic flow was evaluated by using 3-dimensional time-resolved particle traces and velocity vector fields reformatted onto 2-dimensional planes. Semiquantitative data were derived by using a blinded grading system (0-3: 0, none; 1, minimal; 2, medium; 3, prominent) to analyze the systolic vortex formation behind the cusps, as well as retrograde and helical flow in the ascending aorta.

Results: Systolic vortices were seen in both coronary sinuses of all volunteers (greater in the left sinus [2.5 +/- 0.5] than the right [1.8 +/- 0.8]) but in only 4 of 10 noncoronary sinuses (0.7 +/- 0.9). Comparable coronary vortices were detected in all operated patients. Vorticity was minimal in the noncoronary cusp in T. David-I repairs (0.7 +/- 0.7) but was prominent in T. David-V noncoronary graft pseudosinuses (1.5 +/- 0.6; P = .035). Retrograde flow (P = .001) and helicity (P = .028) were found in all patients but were not distinguishable from normal values in the T. David-V-S mod patients.

Conclusions: Coronary cusp vorticity was preserved after David reimplantation, regardless of neosinus creation. Increased retrograde flow and helicity were more prominent in T. David-V patients. These novel magnetic resonance imaging methods can assess the clinical implications of altered aortic flow dynamics in patients undergoing various types of valve-sparing aortic root replacement.

Publication types

  • Comparative Study
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adult
  • Aorta / physiology*
  • Aortic Diseases / diagnosis*
  • Aortic Diseases / physiopathology*
  • Aortic Diseases / surgery
  • Blood Flow Velocity / physiology
  • Blood Vessel Prosthesis Implantation*
  • Female
  • Hemodynamics
  • Humans
  • Imaging, Three-Dimensional
  • Magnetic Resonance Angiography*
  • Male
  • Middle Aged
  • Pulsatile Flow / physiology
  • Time Factors