Feasibility and accuracy of 3DTEE versus CT for the evaluation of aortic valve annulus to left main ostium distance before transcatheter aortic valve implantation.

OBJECTIVES: The aims of this study were to analyze in a large series of patients undergoing transcatheter aortic valve implantation (TAVI): 1) the accuracy of 3-dimensional transesophageal echocardiographic (3DTEE) measurement of left coronary cusp (LCC) length and of the distances from left main coronary ostium (LM) to the aortic annulus (AA) pre-operatively and to the aortic prosthesis post-operatively; and 2) the role of the 3DTEE measurements in predicting the prosthetic deployment and the association between prosthesis position and aortic regurgitation (AR) and/or prosthesis-patient mismatch (PPM).

BACKGROUND: Coronary ostia occlusion is a possible complication in TAVI; therefore, the careful pre-operative evaluation of AA-LM and LCC length, and the post-operative analysis of the relationship between the prosthesis and LM, may influence the procedural outcomes. Even though multidetector computed tomography (MDCT) is the gold standard pre-operatively, sometimes it cannot be performed and it is rarely repeated post-operatively.

METHODS: In 122 patients undergoing TAVI, pre-operative AA-LM and LCC measurements obtained by 3DTEE and MDCT were compared. Post-operatively, the feasibility of 3DTEE evaluation of the prosthesis-LM distance was performed. The relationship between 3DTEE overlap of the prosthesis with the anterior mitral leaflet and AR/PPM was assessed.

RESULTS: Pre-operatively, 3DTEE AA-LM (r = 0.83) and LCC (r = 0.69) significantly correlated with MDCT. Post-operatively, 3DTEE prosthesis-LM distance was 2.1 ± 1.9 mm. The prosthesis reached or exceeded LM in 6 and 10 cases, respectively. Prosthesis overlap with mitral leaflet was 4.7 ± 1.8 mm. Significant correlation between the 3DTEE computed and nominal length of the prosthesis was found (r = 0.61). No correlations were found between prosthesis-mitral leaflet overlap and aortic regurgitation or PPM.

CONCLUSIONS: AA-LM distance and LCC length may be accurately estimated by 3DTEE, which may represent a valid alternative to MDCT. Pre- and post-3DTEE data concerning the aortic root, such as LM, aortic valve, and prosthetic morphology, give new insights into TAVI and its complications.