Objectives: To determine the incidence, timing and predictors of periprocedural valve dislodgment with the Medtronic Corevalve System (MCS). Background: Periprocedural valve dislodgment may occur during transcatheter aortic valve implantation (TAVI). Methods: Ninety-eight consecutive patients underwent TAVI with the MCS after a comprehensive baseline assessment including invasive angiography, echocardiography, and Multi-Slice Computed Tomography (MSCT). The invasive monitoring charts and angiographic studies of all TAVI procedures were reviewed to determine the incidence and timing of valve dislodgment. Results: Valve dislodgment occurred in 18 patients. Patients with valve dislodgment had a larger Aortic Valve Area (0.76 ± 0.25 cm 2 vs. 0.61 ± 0.19 cm 2, P = 0.007), lower mean transaortic gradient (37.65 ± 14.62 mm Hg vs. 47.11 ± 16.08 mm Hg, P = 0.03) and significantly less aortic root calcification (Agatston score median 1951 AU (IQR, 799-3103) vs. 3289 AU (IQR 2097-4481), P = 0.016). A lower aortic root calcium score (Agatston score < 2359 AU) was the single independent predictor for valve dislodgment (OR 3.10, 1.09-8.84). After valve dislodgment, the valve could be successfully retrieved and implanted in the proper anatomic location in all cases. Valve dislodgment was associated with a lower incidence of post-procedural AR ≥ 2 (11.1% vs. 34.6%, P = 0.05). There were no relevant procedural or clinical implications to valve dislodgment. Conclusions: The incidence of periprocedural valve dislodgment was 18% in these series. Less aortic root calcification appeared the single independent predictor.