Long-term outcomes after TAVI in patients with different types of aortic stenosis: the conundrum of low flow, low gradient and low ejection fraction.

AIMS: The objective of this study was to examine the impact of guideline-defined subtypes of severe aortic stenosis (AS) on long-term outcomes after TAVI. METHODS AND
RESULTS: Four hundred (400) consecutive patients who underwent TAVI (203 transapical, 197 transfemoral) at our institution 8/2008-3/2013 were followed systematically (for up to seven years). One hundred and forty-seven (147) individuals suffered from NEF-HG AS (LV-EF ≥50%, high Pmean ≥40 mmHg), 63 from LEF-HG AS (LV-EF <50%, high gradient), 77 from PLF-LG AS (LV-EF ≥50%, low gradient, stroke volume index [SVI] <35 ml/m²), and 81 from LEF-LG AS (LV-EF <50%, low gradient). LEF-LG status was associated with the highest all-cause and cardiovascular mortality and MACCE rate, whereas NEF-HG patients exhibited the best outcome (i.e., median survival 5.1 years in NEF-HG vs. 1.3 years in LEF-LG, p=0.0006; or vs. 3.3 years in PLF-LG, p=0.02). In multivariate analysis, LEF-LG status emerged as the outcome predictor with the highest hazard ratio for all-cause mortality (HR 2.86, p=0.003), cardiovascular mortality (HR 6.53, p<0.0001), and MACCE (HR 2.44, p=0.007), whereas neither baseline EF nor SVI <35 ml/m² independently predicted these endpoints.
CONCLUSIONS: These findings suggest that an assessment of LV-EF alone for outcome prediction after TAVI is inadequate; it is the guideline-defined subtype of AS that determines outcome.