MR imaging and heart function in patients pre- and post-Fontan surgery.

MR imaging allows functional evaluation of the ventricles of the entire heart because it evaluates cardiac anatomy three-dimensionally. Such evaluation is independent of chamber size and shape, and virtually independent of mathematical assumptions. Applying standard measurements of volume and function in children who have undergone multi-staged Fontan operations, we have shown diminished ventricular volumes and mass, and decreased cardiac indices, in post-Fontan procedure. These variations may be predictive of ultimate outcome in these complex patients.