BACKGROUND Predicting improvement of myocardial function after transcatheter aortic valve implantation (TAVI) for aortic stenosis (AS) remains a challenge. As ejection fraction (EF) may be of limited value in detecting early myocardial dysfunction and predicting outcome, we assessed the potential of echocardiographic longitudinal function in this setting. MATERIALS AND METHODS Left ventricular (LV) function was assessed using EF, mitral annular plane systolic excursion (MAPSE), peak longitudinal 2D strain (LS) and strain rate (SR) in101consecutive patients with severe symptomatic AS (age 81 ± 11 years) undergoing TAVI. Echocardiography and assessment of clinical status including NYHA functional class were performed prior and after intervention (median 70 days). RESULTS Pre-interventional EF was 57 ± 17% and 32 patients (32%) had an EF<50% while 58 patients (57%) were found to have an impaired LS. After TAVI there was no significant change in EF. In contrast, LS, SR and MAPSE improved significantly (-14.0 ± 4.4 vs. -15.5 ± 4.0%; p=0.007, 0.68 ± 0.24 vs. 0.78 ± 0.23/s, p=0.002; and 9.1 ± 3.2 vs. 10.2 ± 3.3mm, p=0.006, respectively). Receiver Operating Curve characteristic analysis identified a pre-TAVI LS>-13.3% as the optimal cut-off value for predicting lack of LS recovery post TAVI. There was a marked improvement in NYHA FC after intervention (p=0.0002). Among the studied echocardiographic parameters LS change correlated closest with NYHA class improvement (r=0.42, p=0.0008). CONCLUSION Overall, LS appears to be more sensitive for detecting early myocardial damage in patients with AS compared to conventional echocardiographic parameters. More importantly, pre-interventional LS may identify irreversible myocardial dysfunction and LS improvement correlates with symptomatic improvement after intervention.