Introduction: The geometric shape of the mitral valve annulus has an important impact on the results
of the mitral valve repair. Recent research has shown a broad range of individual
variability in anatomy of mitral valve apparatus both in normal and in diseased states,
i.e. saddle shape and (a-)symmetrical annulus dilatation. Currently, no accurate method
exists for preoperative assessment of mitral annulus shape. We evaluated in this context
the feasibility of a hybrid imaging technique for individualized visualization of
mitral valve annulus geometry prior to operation.
Methods: A total of 15 patients underwent transthoracic 3DE (Sonos, 7500) and cardiac magnetic
resonance imaging (MRI; Siemens, 1.5 T).
Results: The 3DE and MRI data sets were post-processed using a newly developed software (MITK,
DKFZ, Heidelberg), which was implemented with an algorithm for segmentation of the
mitral valve annulus. Additionally, the MRI data sets were used for stereolithographic
reconstruction of every individual heart including the exact geometrical reconstruction
of the mitral valve apparatus. The stereolithographic models were digitally scanned
and visualized as virtual 3D images. The segmentated annulus of each patient was then
virtually implanted into the 3D image stimulating thereby a virtual mitral valve annuloplasty.
Conclusions: Our data show that, using multimodal imaging techniques, an individual-based planning
of the complex cardiac procedures, i.e. mitral valve annuloplasty can be performed
on a virtual model of the patient's heart. We are confident that our data has great
potential for clinical use and can improve the outcome of operations.
