Incidence, Predictors, and Prognostic Impact of Left Ventricular Outflow Tract Obstruction Following Transcatheter Aortic Valve Replacement

Background Dynamic left ventricular outflow tract obstruction (LVOTO) following transcatheter aortic valve replacement (TAVR) is a potential complication that can cause severe haemodinamic instability. However, limited evidence is available regarding the incidence and predictors of LVOTO post-TAVR. This study aimed to clarify the incidence and identify the predictors of LVOTO following TAVR and to investigate whether LVOTO is associated with clinical outcomes. Methods This retrospective, single-center study analysed 2,068 consecutive patients with aortic stenosis who underwent TAVR between January 2014 and December 2023. Transthoracic echocardiography was performed both before and after TAVR. LVOTO was defined as a peak pressure gradient exceeding 30 mmHg. Results LVOTO occurred in 25 of 1,963 patients (1.3%), with 6 patients developing acute haemodinamic compromise immediately after TAVR. Least absolute shrinkage and selection operator penalised regression analysis identified the left ventricular outflow tract dimension (LVOTD), interventricular septum (IVS) thickness, transvalvular velocity, LVOT maximum velocity (Vmax), and aortic annulus-to-LVOT area ratio (A/L ratio) as independent predictors of LVOTO following TAVR. Kaplan–Meier analysis revealed no association between LVOTO following TAVR and all-cause mortality or rehospitalisation for heart failure. Conclusions The incidence of LVOTO after TAVR was 1.27%. Predictors of LVOTO were the IVS thickness, transvalvular velocity, LVOTD, LVOT Vmax, and A/L ratio. Notably, LVOTO following TAVR was not associated with the composite outcome of all-cause mortality or heart failure hospitalisation.