Abstract
Background and purpose
Percutaneous left atrial appendage occlusion (LAAO) depicts an alternative treatment for patients with atrial fibrillation who are deemed for long-term oral anticoagulation therapy. In order to perform a successful LAAO accurate sizing of left atrial appendage (ostium, landing zone and depth) for device selection is essential. Echo-Fluoro fusion imaging in real-time offers with its latest prototype a patient-specific segmented automated 3D heart model and sizing of left atrial appendage (LAA). We therefore aimed to evaluate the automated segmented LAA sizing by comparing to 2D transesophageal (TOE) and MSCT measurements as gold standard.
Methods
We studied prospectively data of 8 consecutive patients who were admitted to our clinic for left atrial appendage closure. MSCT was performed preprocedural and analyzed with commercially available 3mensio software (Pie medical imaging). 2D TOE measurements and automated segmentation of the LAA and sizing were performed during the procedure by a highly experienced team of periinterventional cardiac imaging specialist and structural heart disease interventionalist who were blinded to the prior MSCT analysis. Dimension of ostium, landing zone (10 mm into the LAA parallel to the ostial plane at the level of the left circumflex for Amplatzer device) and depth (perpendicular to the ostial plane) were obtained in different TOE views according to instructions for use of Amulet Occluder. In order to generate an automated 3 D heart model, a high-quality 3D TOE image of the LAA volume and surrounding structures was acquired. After successful ECG-gated segmentation a 3 D heart model was generated. Automated LAA sizing followed in real-time. All measurements were taken into consideration before device selection. A Kruskal Wallis test was used to compare mean ranks of independent samples. A concordance analysis according to Kendall W was carried out to investigate reliability.
Results
The mean age of the patients was 82,6±4.15 years and half of the patients were female. All procedures were conducted successfully. The mean values of ostium and landing zone were comparable in TOE, automated sizing and MSCT sizing (ostium: 23,78±2,15 mm vs 25,71±5,25 mm vs 27,35±3,3 mm; (p=0,175); landing zone 22,13±3,18 mm vs 23,57±3,31 mm vs 24,00±3,51 mm; (p=0,377)). Furthermore, a significant concordance between the measurements was shown (ostium W= 0,991; p=0.045, landing zone W=0,835, p=0.014).
Conclusion
Automated LAA sizing acquired by fusion imaging may be an elegant real-time alternative for precise LAA Occluder device selection and needs to be investigated further.
Subxiphoid Minimally Invasive Epicardial Ablation (Convergent Procedure) With Left Thoracoscopic Closure of the Left Atrial Appendage
