Background: For transcatheter aortic valve implantation (TAVI), accurate determination of valve size is crucial.
Multidetector Computed Tomography (MDCT) is considered gold standard, however sometimes there are conflicting measurements or aortic annulus is ambiguous between 2 prosthesis sizes. In such cases balloon sizing can serve in selecting valve size.

Methods: 110 patients were prospectively enrolled. Aortic annular diameter was measured by 2D TEE. Balloon sizing was done with balloons equal or 1 mm smaller than TEE measurements. Supra-aortic angiography was performed during balloon inflation. Contrast regurgitation and balloon movement indicated annulus size underestimation, balloon wasting indicated annulus size overestimation. Valve size selection was based on balloon sizing. Agreement between 2D TEE and balloon measurements was calculated. Inhospital outcomes related to valve sizing and routine predilation were determined.
Results: TEE was correctly sizing the valve in 81% of patients, oversizing in 17% and undersizing in only 2% compared with balloon sizing. Agreement between 2D TEE and balloon sizing measurement yielded a K value of 0.71. Hemodynamic instability after balloon sizing was observed in 2 patients, valve embolization occurred in one patient, no case of aortic rupture or coronary occlusion was detected. Two patients needed a second valve. Stroke rate was 0.9%, inhospital mortality was 1.8%. At hospital discharge, rate of significant PVL (≥ grade II) was 3.4% and pacemaker implantation rate was 6.4%.
Conclusions: Balloon sizing based on 2D TEE annular measurements represents an appropriate approach for selecting valve size with favorable outcomes.