Background Transcatheter aortic valve implantation (TAVI) has been confirmed to improve the prognosis of high-risk patients with severe aortic stenosis (AS),still little is known about changes in left ventricular (LV)morphology and function after TAVI beyond 12 months.This study evaluated the effect of TAVI on LV morpho-logical and functional adaptation in patients with severe AS 12 months after implantation.Methods AS patients with TAVI were selected from January 2018 to December 2020 in our hospital.Transthoracic echocardiography was performed before and 12 months after TAVI to determine LV morphology and LV function.Morphological parameters,such as left ventricular end-diastolic (LVDd) dimension,left ventricular end-systolic (LVDs) dimen-sion,interventricular septum thickness (IVST),posterior wall thicknesses (PWT),left ventricular mass (LVM),and left ventricular mass index (LVMI) were included.Left ventricular ejection fraction (LVEF) and Tissue Dop-pler imaging (TDI)-derived peak systolic myocardial velocity (S\') were recorded to assess LV function.Results A total of 58 consecutive patients with severe AS who underwent TAVI were included.In all subjects,TAVI re-markably reduced peak transaortic velocity (4.6±0.6 m/s at baseline vs.2.0±0.5 m/s after TAVI,P＜0.001) and mean transaortic gradient (51± 15.8 mmHg at baseline vs.5.3±3.6 mmHg after TAVI,P＜0.001),and improved aortic valve area (AVA) significantly (0.7±0.2 cm2 at baseline vs.1.8±0.4 cm2 after TAVI,P＜0.001).IVST re-gressed from 14.1±8.2 mm to 12.5±3.1 mm and PWT from 13.3±7.1 mm to 10.8±2.9 mm (P＜0.05).LV mass and LV mass index decreased from 316±98 g to 219±62 g (P＜0.001) and from 182±46 g/m2 to 118±28 g/m2 (P＜0.001),respectively.There was a statistically significant improvement in LV function (LVEF:50.6％±11.3％ at baseline vs.65.1％±7.6％ after TAVI;S\':3.4±1.3 cm/s at baseline vs.4.5±1.4 cm/s after TAVI,P＜0.05).Howev-er,LVDd (45.2±10.6 mm at baseline vs.49.1±5.5 mm after TAVI,P=0.235) and LVDs (30.4±12.3 mm at base-line vs.34.6±4.3 mm after TAVI,P=0.346) did not change remarkably.Conclusions Significant LV function improvement and LV hypertrophy regression were found in patients with severe AS 12 months after TAVI.These changes suggested that TAVI can reverse LV remodeling.