Assessment of aortic annulus dimensions for Edwards SAPIEN Transapical Heart Valve implantation by computed tomography: calculating average diameter using a virtual ring method.
OBJECTIVE
Accurate preoperative assessment of the aortic annulus dimensions is critical in patients undergoing transcatheter aortic valve implantation (TAVI) for severe AS. Using multislice computed tomography (MSCT), we evaluated a novel approach to quantify aortic annulus dimensions using cross-sectional area (CSA) assessment and average diameter calculation compared with the commonly applied electronic caliper measurements in patients undergoing transapical implantation of the Edwards SAPIEN Transcatheter Heart Valve.


METHODS
Seventy-one patients underwent pre-TAVI MSCT with the following dimensions assessed at the level of the most basal attachment points of all three aortic cusps joined by a virtual ring: CSA, calculated average annulus diameter (CAAD), and minimal, maximum, sagittal and coronal diameters. Measurements were compared with post-TAVI MSCT data sets at the level of the ventricular stent ending in 24 patients. Pre-TAVI measurements were compared to those taken post-TAVI. Eligibility to balloon-expandable TAVI was evaluated based on the different measurements.


RESULTS
The Edwards SAPIEN valve (23 mm, n=8; 26 mm, n=16) was implanted 2.1±1.1 mm below the non-coronary sinus. Pre-TAVI CAAD was 23.0±1.6 mm; post-TAVI CAAD was 23.0±1.1 mm. Post-TAVI CSA was circular in 18 patients (75%) and ovoid in six (25%). Pre- and post-TAVI assessment showed strong correlation for CSA and CAAD (r=0.835, p<0.001; r=0.841, p<0.001, respectively). Minimal, maximum, coronal and sagittal dimension correlated weakly between pre- and post-TAVI measurements (r=0.435-0.632, p=0.001-0.034).


CONCLUSIONS
Pre-TAVI CSA assessment and average diameter calculation using a virtual ring method is able to predict the post-interventional configuration of the annulus after balloon-expandable TAVI. We regard this approach as the best-available method to select the appropriate prosthesis size for balloon-expandable TAVI. Specific MSCT-based sizing recommendations should be developed.
Blanke
Philipp
P
Department of Diagnostic Radiology, University Hospital Freiburg, Hugstetter Str. 55, 79104 Freiburg, Germany. philipp.blanke@uniklinik-freiburg.de
Siepe
Matthias
M
Reinöhl
Jochen
J
Zehender
Manfred
M
Beyersdorf
Friedhelm
F
Schlensak
Christian
C
Langer
Mathias
M
Pache
Gregor
G
D000368:Aged; D000369:Aged, 80 and over; D001021:Aortic Valve / Q000000981:diagnostic imaging / Q000473:pathology; D001022:Aortic Valve Insufficiency / Q000209:etiology; D001024:Aortic Valve Stenosis / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D017548:Echocardiography, Transesophageal / Q000379:methods; D005260:Female; D006350:Heart Valve Prosthesis; D019918:Heart Valve Prosthesis Implantation / Q000379:methods*; D006801:Humans; D008297:Male; D015588:Observer Variation; D011474:Prosthesis Design; D015203:Reproducibility of Results; D014057:Tomography, X-Ray Computed / Q000379:methods