Three-Dimensional Echocardiography Compared With Computed Tomography to Determine Mitral Annulus Size Before Transcatheter Mitral Valve Implantation.
BACKGROUND
Previously, through the use of computed tomography (CT), it has been proposed that D-shaped versus saddle-shaped mitral annulus (MA) segmentation is more biomechanically appropriate to determine transcatheter mitral valve implantation size and eligibility.


RESULTS
Forty-one patients with severe mitral regurgitation being considered for transcatheter mitral valve implantation who had undergone cardiac CT and 3-dimensional transesophageal echocardiography (3D-TEE) were retrospectively evaluated. A standardized segmentation protocol for the D-shaped MA was developed using Philips Q-Laboratory mitral valve quantification software. MA dimensions were compared using Spearman's rank correlation and Bland-Altman analysis. Inter- and intraobserver agreement was quantified by intraclass correlation coefficient and Bland-Altman analysis. Mean age was 77±14 years; 71% male (n=29); mitral regurgitation pathogenesis was functional in 54% (n=22) and myxomatous in 46% (n=19). Mean MA area and circumference by 3D-TEE and CT were 11.3±2.7 versus 11.4±3.0 (P=0.67) and 124.1±15.6 versus 123.9±15.5 (P=0.79), respectively, with excellent correlation between modalities (r=0.84 and r=0.86; P<0.0001) and no systematic bias (-0.20±1.8 cm(2) [-3.7 cm(2); 3.3 cm(2)], 0.37±9 mm [-18.0 mm; 17.27 mm]). Mean septal-to-lateral and inter-trigone distances by 3D-TEE and CT were 33.2±4.7 versus 32.5±4.4 (P=0.24) and 31.7±3.5 versus 32.6±3.6 (P=0.06), respectively, with good correlation (r=0.69 and r=0.71; P<0.0001) and no systematic bias (0.77±3.8 mm [-6.7 mm; 8.2 mm], -1.5±3.1 mm [-4.6 mm; 7.6 mm]). There was excellent intra- and interobserver agreement according to intraclass correlation coefficients >0.90 for all parameters.


CONCLUSIONS
Similar to cardiac CT, 3D-TEE allows for D-shaped MA segmentation with no systematic difference in MA dimensions between modalities. This study supports the utilization of 3D-TEE as a complementary tool to CT assessment of the D-shaped MA to determine transcatheter mitral valve implantation size.
From the St Paul's Hospital, University of British Columbia, Vancouver, Canada.
George J
GJ
Mak
From the St Paul's Hospital, University of British Columbia, Vancouver, Canada.
Philipp
P
Blanke
From the St Paul's Hospital, University of British Columbia, Vancouver, Canada.
Kevin
K
Ong
From the St Paul's Hospital, University of British Columbia, Vancouver, Canada.
Christopher
C
Naoum
From the St Paul's Hospital, University of British Columbia, Vancouver, Canada.
Christopher R
CR
Thompson
From the St Paul's Hospital, University of British Columbia, Vancouver, Canada.
John G
JG
Webb
From the St Paul's Hospital, University of British Columbia, Vancouver, Canada.
Robert
R
Moss
From the St Paul's Hospital, University of British Columbia, Vancouver, Canada.
Robert
R
Boone
From the St Paul's Hospital, University of British Columbia, Vancouver, Canada.
Jian
J
Ye
From the St Paul's Hospital, University of British Columbia, Vancouver, Canada.
Anson
A
Cheung
From the St Paul's Hospital, University of British Columbia, Vancouver, Canada.
Brad
B
Munt
From the St Paul's Hospital, University of British Columbia, Vancouver, Canada.
Jonathon
J
Leipsic
From the St Paul's Hospital, University of British Columbia, Vancouver, Canada. jagrewal@providencehealth.bc.ca.
Jasmine
J
Grewal
D000368:Aged; D000369:Aged, 80 and over; D006328:Cardiac Catheterization / Q000295:instrumentation* / Q000379:methods; D019560:Echocardiography, Three-Dimensional; D017548:Echocardiography, Transesophageal; D005240:Feasibility Studies; D005260:Female; D006350:Heart Valve Prosthesis; D019918:Heart Valve Prosthesis Implantation / Q000295:instrumentation* / Q000379:methods; D006801:Humans; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve / Q000000981:diagnostic imaging* / Q000503:physiopathology; D008944:Mitral Valve Insufficiency / Q000000981:diagnostic imaging* / Q000503:physiopathology / Q000628:therapy; D061330:Multidetector Computed Tomography; D015588:Observer Variation; D011237:Predictive Value of Tests; D011474:Prosthesis Design; D011857:Radiographic Image Interpretation, Computer-Assisted; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012720:Severity of Illness Index
3D echocardiography; TMVI; TMVR; computed tomography; mitral valve annulus; percutaneous valve implantation; transcatheter