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Published on: June 3, 2018
Quantification of Commissural Alignment of Balloon-Expandable THV on Fluoroscopy: A Comparison Study With Post-TAVR
Mariama Akodad1, Georgios Tzimas1, David Meier1
1Centres for Heart Valve Innovation and for Cardiovascular Innovation, St Paul's and Vancouver General Hospitals, Division of Cardiology and Department of Radiology, University of British Columbia, Vancouver, British Columbia, Canada.
Insights
Assessing transcatheter heart valve (THV) commissural alignment after TAVR using fluoroscopy is reliable. This trigonometric method accurately correlates with CT, aiding procedural success and future coronary access.
Area of Science:
- Cardiology
- Interventional Cardiology
- Medical Imaging
Background:
- Transcatheter aortic valve replacement (TAVR) can lead to challenging coronary access if the transcatheter heart valve (THV) is commissurally misaligned.
- Accurate assessment of THV alignment is crucial for procedural success and patient outcomes.
Purpose of the Study:
- To quantify commissural alignment after balloon-expandable THV implantation using a fluoroscopy-based trigonometric method.
- To evaluate the correlation between fluoroscopic assessment and post-TAVR computed tomography (CT) findings.
Main Methods:
- Analysis of 20 patients who underwent TAVR with SAPIEN 3 THV and post-TAVR CT.
- Utilized a standardized 3-cusp angiographic view for predeployment and postdeployment fluoroscopy.
- Calculated commissural alignment using a trigonometric approach (arcsine function) and stratified into four tiers.
Main Results:
- Strong agreement between CT and fluoroscopy for commissural alignment assessment (weighted Cohen's kappa = 0.724).
- Excellent correlation (r = 0.986) between fluoroscopically and CT-derived commissural offset angles.
- Bland-Altman analysis showed good agreement with a mean difference of 0.5°.
Conclusions:
- Fluoroscopy, using a standardized 3-cusp view and trigonometric analysis, reliably assesses and quantifies balloon-expandable THV commissural alignment post-TAVR.
- This method provides accurate and reproducible alignment assessment, aiding in procedural planning and evaluation.
Background:
Coronary access may be challenging following transcatheter aortic valve replacement (TAVR) in the setting of transcatheter heart valve (THV) commissural misalignment.
Objectives:
The authors aimed to quantify the degree of commissural alignment following balloon-expandable THV implantation using a fluoroscopy-based trigonometric approach and assess its correlation with post-TAVR computed tomography (CT).
Methods:
Twenty patients who had undergone both TAVR with the balloon-expandable SAPIEN 3 THV and post-TAVR CT were included in the analysis. Optimized, predeployment 3-cusp angiographic view and postdeployment angiographic view using identical fluoroscopic projections were required. The distance between the most central posterior commissural strut and the THV centerline was assessed. Commissural alignment was calculated by means of a trigonometrical approach using an arcsine function, assuming circular deployment of the THV. Commissural alignment was stratified using a 4-tier scale: aligned (0° to 15°); mildly misaligned (15° to 30°); moderately misaligned (30° to 45°), and severely misaligned (45° to 60°).
Results:
Seven patients (35.0%) were misclassified by 1 tier, and no patient was misclassified by 2 or more tiers, with strong agreement between CT and fluoroscopy (weighted Cohen's kappa coefficient = 0.724). Correlation of the commissural offset angle determined from fluoroscopy and CT was excellent (r = 0.986; 95% CI: 0.965 to 0.995). Bland-Altman analysis demonstrated a strong agreement between both modalities with a mean difference of 0.5° (95% limits of agreement: -12.7° to 13.7°).
Conclusions:
The degree of commissural alignment of the balloon-expandable THV can be reliably assessed and quantified on postdeployment fluoroscopy using a standardized 3-cusp view and trigonometry-based analysis.
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