Prevalence of iron deficiency and its influence on six-minute walk test distance in patients eligible for transcatheter aortic valve implantation. A prospective study.

Abstract

Introduction: Aortic stenosis (AS) leads to left ventricular outflow tract obstruction and can result in the development of heart failure. Patients with severe AS exhibit similar symptoms to those with iron deficiency (ID), raising the question of whether ID, if diagnosed, could be linked to the lack of physical performance improvement after transcatheter aortic valve implantation (TAVI).

Aim: The aim was to assess the prevalence of ID in patients scheduled for TAVI and to evaluate its impact on 6-minute walk test (6MWT) results.

Material and methods: Patients with severe AS, qualified for TAVI, were tested for ID, and underwent 6MWT with the assessment of heart rate recovery (HRR) parameters before TAVI and after 3 months.

Results: ID was diagnosed in 59% of screened patients. There was no significant difference in baseline (277.6 ±121.9 m vs. 287.3 ±116.6 m; p = 0.74) and follow-up 6MWT distance (313.1 ±119.6 m vs. 319.4 ±111 m; p = 0.93) between the two study arms. In both groups the 6MWT distance improved significantly after TAVI (32.1 ±62.9 m in ID group, p < 0.003; (39.4 ±68.7 m in non-ID group, p < 0.005). There were no statistical differences in HRR parameters between the two groups before and after TAVI.

Conclusions: The results of the study indicate that ID has no significant effect on 6MWT results before and after the TAVI procedure. ID likely has no impact on physical capacity in patients with severe AS.