Department updates» Go to news main
A simplified D‑shaped model of the mitral annulus to facilitate CT‑based sizing before transcatheter mitral valve implantation
See full publication
The nonplanar, saddle-shaped structure of the mitral annulus has been well established through decades of anatomic and echocardiographic study. Its relevance for mitral annular assessment for transcatheter mitral valve implantation is uncertain.
Our objectives are to define the methodology for CT-based simplified "D-shaped" mitral annular assessment for transcatheter mitral valve implantation and compare these measurements to traditional "saddle-shaped" mitral annular assessment.
The annular contour was manually segmented, and fibrous trigones were identified using electrocardiogram-gated diastolic CT data sets of 28 patients with severe functional mitral regurgitation, yielding annular perimeter, projected area, trigone-to-trigone (TT) distance, and septal-lateral distance. In contrast to the traditional saddle-shaped annulus, the D-shaped annulus was defined as being limited anteriorly by the TT distance, excluding the aortomitral continuity. Hypothetical left ventricular outflow tract (LVOT) clearance was assessed.
Projected area, perimeter, and septal-lateral distance were found to be significantly smaller for the D-shaped annulus (11.2 ± 2.7 vs 13.0 ± 3.0 cm(2); 124.1 ± 15.1 vs 136.0 ± 15.5 mm; and 32.1 ± 4.0 vs 40.1 ± 4.9 mm, respectively; P < .001). TT distances were identical (32.7 ± 4.1 mm). Hypothetical LVOT clearance was significantly lower for the saddle-shaped annulus than for the D-shaped annulus (10.7 ± 2.2 vs 17.5 ± 3.0 mm; P < .001).
By truncating the anterior horn of the saddle-shaped annular contour at the TT distance, the resulting more planar and smaller D-shaped annulus projects less onto the LVOT, yielding a significantly larger hypothetical LVOT clearance than the saddle-shaped approach. CT-based mitral annular assessment may aid preprocedural sizing, ensuring appropriate patient and device selection.
Copyright © 2014 Society of Cardiovascular Computed Tomography. Published by Elsevier Inc. All rights reserved.
- RRF studentship application deadline Feb 3rd
- Looking for research pitches
- CSTR 2020 – Focus on Lung Screening
- Department Head Update
- Congrats Dr. Mata‑Mbemba
- Psychotic symptoms are associated with lower cortical folding in youth at risk for mental illness
- Experience with compressed gelfoam plugs in children during liver biopsies and other IR procedures: a retrospective single‑center case series
- Dr. Efford new Modality Lead for CT
comments powered by Disqus