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Optimisation of transcatheter aortic balloon-expandable valve deployment: the two-step inflation technique
Freek Nijhoff1, Pierfrancesco Agostoni, Mariam Samim
1Department of Cardiology, University Medical Center Utrecht, Utrecht, The Netherlands.
Aims:
To evaluate the two-step inflation technique aimed at achieving optimal valve implantation depth (defined as 40% of prosthesis height extending below the lower sinus border on angiography) during balloon-expandable transcatheter aortic valve implantation (TAVI).
Methods And Results:
Between September 2010 and March 2013, 103 patients (67 females, mean age 80.9±5.6 years) were treated with the Edwards SAPIEN XT prosthesis using the two-step inflation technique. Implantation depth was measured on angiography. A historical control group (treated with Edwards SAPIEN) was used for comparison (n=20). Deviation from the defined optimum implantation depth (expressed as a percentage of stent frame height) was significantly less in the study group versus controls (7.0 [3.4-14.1]% vs. 13.9 [5.4-18.9]%; p=0.048). Valve placement was graded "as intended"/"within range"/"out of range" (defined as ≤10%, >10% but ≤20% and >20% deviation, respectively) in 66%/22%/12% of the study group and 35%/40%/25% of historical controls (p=0.02). Corrections in valve position were made in 20 procedures (20%), resulting in placement as intended in 16 cases (80%), with highest efficacy in the transapical and direct aortic approaches.
Conclusions:
The two-step inflation technique improves valve placement towards optimal implantation depth and may thereby prevent adverse events due to malpositioning.