Aortic root remodeling: functional MRI as an accurate tool for complete follow-up.
BACKGROUND
After aortic valve-sparing procedures patients should be evaluated regularly because of the risk for further disease progression in the remaining aorta as well as recurrent aortic insufficiency. The purpose of this study was to evaluate the potential of functional MRI as a single examination for complete follow-up of these patients.


METHODS
Twenty-two patients with a mean age of 54 years (range 30 - 66) were prospectively examined at 1, 12, 24, 36, and 74 months postoperatively, following a Yacoub aortic root remodeling operation, using a 1.5 T MRI. The original disease was chronic aneurysm of the ascending aorta or root in 17, chronic dissection in 3, and acute dissection in 2 patients. Transverse graft diameters, regurgitant fraction, LVEDV, and cardiac index were measured using cine MRI. Results were compared to spiral computed tomography and transthoracic color Doppler echocardiography. Mean time of follow-up was 24.9 months and ranged from 1 to 74 months.


RESULTS
There were 2 re-operations, 2 years after primary surgery, due to high aortic insufficiency. CT and MRI measurements of graft diameters correlated well (p = 0.4544). Mean graft diameter (mean +/- SD) was 30 +/- 3.7, 33 +/- 3.4, 36.5 +/- 1.5, 37 +/- 2.8, and 38.3 +/- 2.8 mm at 1, 12, 24, 36, and 74 months, respectively, indicating a significant increase of graft diameter (p < 0.0001). Mean regurgitant fraction as determined by MRI was 14 +/- 7, 12 +/- 9, 13 +/- 9, 15 +/- 7, and 14 +/- 9 % at 1, 12, 24, 36, and 74 months, respectively. Flow based grading of aortic insufficiency by MR imaging correlated well with color Doppler echocardiography (p < 0.0001).


CONCLUSIONS
MRI provides an excellent, noninvasive, comprehensive tool for follow-up after valve-sparing aortic root reconstruction. The determination of regurgitant fraction, ventricular dimensions and functions, and graft diameters allows standardized imaging protocols with a high reproducibility, which may lead to this technique being favored for the follow-up of patients after aortic root remodeling.
Givehchian
M
M
Department of Thoracic, Cardiac, and Vascular Surgery, University of Tübingen, Tübingen, Germany.
Kramer
U
U
Miller
S
S
Hahn
U
U
Scheule
A M
AM
Ziemer
G
G
Aebert
H
H
D000328:Adult; D000368:Aged; D000784:Aortic Dissection / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery; D001014:Aortic Aneurysm / Q000175:diagnosis* / Q000503:physiopathology / Q000601:surgery; D001022:Aortic Valve Insufficiency / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery; D001026:Coronary Artery Bypass; D003324:Coronary Artery Disease / Q000175:diagnosis / Q000601:surgery; D018618:Echocardiography, Doppler, Color; D005260:Female; D005500:Follow-Up Studies; D019918:Heart Valve Prosthesis Implantation; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods* / Q000592:standards; D008297:Male; D008875:Middle Aged; D008944:Mitral Valve Insufficiency / Q000175:diagnosis / Q000601:surgery; D011446:Prospective Studies; D015203:Reproducibility of Results; D013223:Statistics as Topic; D036542:Tomography, Spiral Computed; D016896:Treatment Outcome