Transcatheter aortic valve implantation in patients with low-flow, low-gradient aortic stenosis.

OBJECTIVES: The purpose of this study was to evaluate the efficacy and outcome of transcatheter aortic valve implantation (TAVI) in patients with low-flow, low-gradient aortic stenosis (LG-AS).

BACKGROUND: Patients with LG-AS have a poor prognosis with medical treatment and a high risk for surgical aortic valve replacement.

METHODS: Between January 2009 and June 2010, a total of 1,302 patients underwent TAVI for severe AS and were prospectively included in the multicenter German TAVI registry.

RESULTS: LG-AS was present in 149 patients (11.4%; mean age: 80.2 ± 6.3 years). In this subgroup, the EuroSCORE was significantly higher (26.8 ± 16.6 vs. 20.0 ± 13.3; p < 0.0001) compared with patients with high-gradient AS (HG-AS). The procedural success rate (LG-AS: 95.3% vs. HG-AS: 97.5%; p = 0.13) and the rate of TAVI-associated complications were comparable in both groups (new pacemaker: 27.0% vs. 28.1%; p = 0.76; cerebrovascular events: 3.4% vs. 3.1%, p = 0.83). However, post-operative low-output syndrome occurred more frequently in the LG-AS-group (LG-AS: 14.9% vs. HG-AS: 5.7%, p < 0.0001), and mortality at 30 days and 1 year was significantly higher in this subgroup (LG-AS: 12.8% and 36.9% vs. HG-AS: 7.4% and 18.1%; p < 0.001 and p < 0.0001, respectively). Post-operative New York Heart Association functional class improved, and self-assessed quality of life increased significantly, demonstrating a substantial benefit in the LG-AS group at 30 days and 1 year after TAVI.

CONCLUSIONS: In high-risk patients with LG-AS, TAVI is associated with a significantly higher mortality at 30 days and at 1 year. However, long-term survivors benefit from TAVI with functional improvement and a significantly increased quality of life. Therefore, in view of the poor prognosis with medical treatment, TAVI should be considered an option in high-risk patients with LG-AS.