Previous studies showed that the paradoxical low-flow, low-gradient (PLFLG) aortic stenosis (AS) is a highly challenging condition in terms of diagnostics and therapy. Moreover, this subgroup demonstrates an increased all-cause mortality if treated medically compared to surgically treated patients. The aim of this study was to investigate the clinical outcome and mortality in patients with PLFLG AS after transcatheter aortic valve implantation (TAVI).

450 consecutive patients in high operative risk underwent TAVI with the Medtronic Corevalve (Medtronic, Minneapolis, MN, USA) or Edwards Sapien (Edwards Lifesience, Irvine, CA, USA) prostheses at our institution between June 2008 and February 2012. Full data of 341 patients was collected. Of these, 190 patients presented with normal-flow, high gradient (NFHG) AS (aortic surface area (ASA) < 1.0 cm², mean gradient (ΔPmean) > 30 mmHg, left ventricular ejection fraction (LVEF) > 50%) and 28 patients with PLFLG AS (ASA < 1.0 cm², ΔPmean < 30 mmHg, LVEF > 50%, stroke volume index (SVI) < 35 ml/m²). Clinical follow-up, echocardiography and measurements of NT-pro-BNP levels were analyzed at 10 days, 4 weeks, 6 month and 1 year after TAVI.

Patients with PLFLG AS had a similiar all-cause mortality at 12 month after TAVI compared to patients with NFHG AS (85% vs. 85.6%, p=0.771). The LVEF decreased slightly but significant after 4 weeks (before 60.1 ± 1.9% vs. 4 weeks 57.5 ± 5.5%, p=0.049), but remained stable after 6 month (57.6 ± 5.1%) and 1 year (56.9 ± 5.7%). Furthermore, patients with PLFLG AS showed slightly high values of NT-pro-BNP at baseline but a similar reduction over time (PLFLG: before 3845 ± 2966 ng/L vs. 1 year 2260 ± 1814 ng/L, p=0.079) in conjunction to reduced symptoms of heart failure. NYHA functional capacity improved similar between both groups (PLFLG vs. NFHG: Δ4 weeks: −1 ± 0.7 vs. −1.2 ± 0.8; p=n.s.; Δ6 month: −0.9 ± 0.7 vs. −1.3 ± 0.8; p=n.s.; Δ12 month: −1.3 ± 1 vs. −1.2 ± 0.8; p=n.s.).

This study shows that patients with PLFLG AS have a similar benefit after TAVI as patients with NFHG AS and should no longer be withheld from TAVI procedures.