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.