Transcatheter aortic valve implantation for paradoxical low-flow low-gradient aortic stenosis patients

Abstract

Objectives: We compared the outcomes of transcatheter aortic valve implantation (TAVI) in three different aortic stenosis syndromes: paradoxical low-flow low-gradient aortic stenosis (PLFLG), high-gradient aortic stenosis (HGAS), and low ejection fraction low-gradient severe aortic stenosis (LEF-LG).

Background: Outcomes for PLFLG patients after TAVI procedure are not well known.

Methods: Between 2010 and 2013, patients with severe (indexed aortic valve area iAVA≤0.6 cm(2)/m(2)) symptomatic aortic stenosis were consecutively referred to our institution for TAVI because of multiple comorbidities and excessive surgical risk. About 262 patients were split into three groups as following, PLFLG: mean gradient MG≤40 mm Hg, stroke volume index SVI≤35 mL/m(2), ejection fraction EF≥55%, valvuloarterial impedance Zva>4.5 mm Hg/mL/m(2), maximal aortic jet velocity MaxV<4 m/s;

Lef-lg: MG≤40 mm Hg, MaxV<4 m/s, EF≤50%, SVI≤35 mL/m(2); and HGAS: MaxV>4 m/s, MG>40 mm Hg, EF>55%. The primary endpoint of our study was to evaluate mid-term global and cardiovascular mortalities; secondary endpoints included recommended VARC-2 variables.

Results: PLFLG (n = 31) mid-term survival was similar to HGAS (n = 172) (mean follow-up = 13.2 months [4.6-26]). Conversely LEF-LG patients (n = 59) displayed significant higher rates of all-cause (P = 0.01) and cardiovascular mortalities (P = 0.05). Postprocedural outcomes (VARC-2 criteria) were similar in the PLFLG and HGAS groups except regarding major bleeding (P = 0.02), while the LEF-LG group had more congestive heart failure and a higher BNP before discharge (both P < 0.001) than the other groups. 30-days deaths were significantly more frequent in LEF-LG and PLFLG in comparison to HGAS (P = 0.03).

Conclusion: As opposed to LEF-LG patients, mid-term prognosis after TAVI procedure in PLFLG patients is similar to HGAS patients despite higher perioperative mortality.

Keywords: aortic stenosis; low ejection fraction low-gradient aortic stenosis; paradoxical low-flow low-gradient aortic stenosis; transcatheter aortic valve implantation.