Clinical presentation and outcomes after transcatheter aortic valve implantation in patients with low flow/low gradient severe aortic stenosis

OBJECTIVES: To identify predictors of mortality, functional status, and hemodynamical changes of patients undergoing transcatheter aortic valve implantation (TAVI) for low flow/low gradient aortic stenosis (LF/LG AS). BACKGROUND: There is little published data regarding the outcomes of patients with LF/LG AS following TAVI. METHODS: Sixty-eight patients with severe AS, left ventricular dysfunction (ejection fraction EF 40 mm Hg). The baseline parameters and clinical outcomes were subsequently compared among the two groups. Cox proportional hazards were used to identify predictors of 6-month mortality. RESULTS: There were 38 patients in the LG group and 30 patients in the HG group. There were no significant difference in 30-day mortality between the two groups. The 6-month and 1-year mortality, however, was 3.8-fold and 2.8-fold higher in the LG group than in the HG group (37.8% vs. 10.3%, P = 0.01 and 37.8% vs. 13.3%, respectively, P = 0.01). Univariable predictors for 6-month mortality were: STS Score, aortic valve area, and aortic mean pressure gradient. However, only STS Score (HR 1.08, 1.04-1.12, P 50%) and clinical (NYHA class I) improvements were shown in both HG and LG groups. CONCLUSIONS: LF/LG AS does not influence procedural mortality after TAVI but exhibits a strong impact on 6-month and 1-year mortality. The survivors, however, exhibit considerable hemodynamical and clinical improvements. Therefore, risk stratification and TAVI benefit should be weighted in every patient with LF/LG AS.