Author + information
- Received April 1, 2011
- Revision received June 30, 2011
- Accepted July 21, 2011
- Published online November 1, 2011.
- Ronen Gurvitch, MBBS⁎,
- John G. Webb, MD⁎,
- Ren Yuan, MD⁎,
- Mark Johnson, MBBS⁎,
- Cameron Hague, MD⁎,
- Alexander B. Willson, MBBS⁎,
- Stefan Toggweiler, MD⁎,
- David A. Wood, MD⁎,
- Jian Ye, MD⁎,
- Robert Moss, MD⁎,
- Christopher R. Thompson, MD⁎,
- Stephan Achenbach, MD†,
- James K. Min, MD‡,
- Troy M. LaBounty, MD‡,
- Ricardo Cury, MD§ and
- Jonathon Leipsic, MD⁎,⁎ ()
- ↵⁎Reprint requests and correspondence:
Dr. Jonathon Leipsic, St Paul's Hospital, 1081 Burrard Street, Vancouver, British Columbia V6Z 1Y6, Canada
Objectives This study sought to determine the most reproducible multidetector computed tomography (MDCT) measurements of the aortic annulus and to determine methods to improve the applicability of these measurements for transcatheter aortic valve implantation.
Background The reproducibility and applicability of MDCT annular measurements to guide transcatheter aortic valve implantation remain unclear.
Methods Annular measurements were performed in 50 patients planed for transcatheter aortic valve implantation in multiple planes: basal ring (short- and long-axis, mean diameter, area-derived diameter), coronal, sagittal, and 3-chamber projections. A theoretical model was developed taking into account the differences between the most reproducible MDCT measurements and transesophageal echocardiography to guide valve size choice.
Results The most reproducible measurements were the area-derived diameter and basal ring average diameter (inter-reader intraclass correlation coefficient: 0.87 [95% confidence interval: 0.81 to 0.92] and 0.80 [95% confidence interval: 0.70 to 0.87]; respectively; intrareader >0.90 for all readers). These were generally larger than transesophageal echocardiography diameters (mean difference of 1.5 ± 1.6 mm and 1.1 ± 1.7 mm, respectively). When a strategy of valve-sizing is undertaken using these CT measurements using an echocardiographic sizing scale, a different THV size would be selected in 44% and 40% of cases, respectively. When adjusting the sizing cutoffs to account for the differences in observed diameters, this was reduced to 10% to 12% (p < 0.01 for both, respectively).
Conclusions The most reproducible MDCT measurements of the annulus are the area-derived diameter and basal ring average diameter, with derived values generally larger than those obtained with echocardiography. If MDCT is used for valve sizing, a strategy incorporating these differences may be important. MDCT using these easily derived measurements may be ideally suited to sizing transcatheter aortic valves as they account for the eccentricity of the aortic annulus, are reproducible, and are noninvasive.
Dr. Webb is a consultant for Siemens and Edwards Lifesciences. Dr. Wood is a consultant for Edwards Lifesciences. Dr. Ye is a consultant to Edwards Lifesciences. Dr. Achenbach receives research support from Siemens Healthcare and Bayer Schering. Dr. Min is on the Speaker's Bureau of GE Healthcare; is a consultant for Edwards Lifesciences; and has equity interest in TC3. Dr. Leipsic is on the Speaker's Bureau and advisory board of Edwards Lifesciences; and he is on the Speaker's Bureau for GE Healthcare and Equity Stakeholder TC3 Corelab. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose.
- Received April 1, 2011.
- Revision received June 30, 2011.
- Accepted July 21, 2011.
- American College of Cardiology Foundation