Flow Reserve Does Not Predict Long‐Term Outcomes After Transaortic Valve Implantation in Patients With Preserved Left Ventricular Ejection Fraction

PURPOSE: We aimed to assess if flow reserve (FR) in low-dose dobutamine stress echocardiography (DSE) could predict major cardiovascular events (MACE) 1 year after TAVI in patients with severe aortic stenosis (AS) and preserved left ventricular ejection fraction (LVEF). We also explored the relationship between FR and NYHA class, 6-min walk test, left ventricular function, and quality of life (SF-36). METHODS: The DSE protocol (n = 72) was performed up to 20 μg/kg/min preoperatively, and FR was defined as ≥ 20% increase in stroke volume (SV). Echocardiography, walking test, and SF-36 were repeated at 12 months follow-up. RESULTS: Average age was 80 ± 5 years. Preoperative peak aortic valve velocity was 4.7 ± 0.6 m/s and LVEF was 65% ± 9%. SV increased from 81 ± 19 to 92 ± 20 mL during the DSE. Twenty-five patients (36%) had FR. The prevalence of MACE was 13% at follow-up. Patients with or without FR had no significant differences in MACE (p = 1.000), NYHA class (p = 0.375), walking distance (p = 0.262), left ventricular function, or quality of life. CONCLUSION: FR in DSE could not predict long-term outcomes after TAVI, and offered no additional prognostic value for this patient group.