Impact of Left Ventricular Outflow Tract Calcification on Procedural Outcomes After Transcatheter Aortic Valve Replacement

Abstract

Objectives: This study aimed to systematically assess the importance of left ventricular outflow tract (LVOT) calcification on procedural outcomes and device performances with contemporary transcatheter heart valve (THV) systems.

Background: LVOT calcification has been associated with adverse clinical outcomes after transcatheter aortic valve replacement (TAVR). However, the available evidence is limited to observational data with modest numbers and incomplete assessment of the effect of the different THV systems.

Methods: In a retrospective analysis of a prospective single-center registry, LVOT calcification was assessed in a semiquantitative fashion. Moderate or severe LVOT calcification was documented in the presence of 2 nodules of calcification, or 1 extending >5 mm in any direction, or covering >10 % of the perimeter of the LVOT.

Results: Among 1,635 patients undergoing TAVR between 2007 and 2018, moderate or severe LVOT calcification was found in 407 (24.9%). Patients with moderate or severe LVOT calcification had significantly higher incidences of annular rupture (2.3% vs. 0.2%; p < 0.001), bailout valve-in-valve implantation (2.9% vs. 0.8%; p = 0.004), and residual aortic regurgitation (11.1% vs. 6.3%; p = 0.002). Balloon-expandable valves conferred a higher risk of annular rupture in the presence of moderate or severe LVOT calcification (4.0% vs. 0.4%; p = 0.002) as compared with the other valve designs. There was no significant interaction of valve design or generation and LVOT calcification with regard to the occurrence of bailout valve-in-valve implantation and residual aortic regurgitation.

Conclusions: Moderate or severe LVOT calcification confers increased risks of annular rupture, residual aortic regurgitation, and implantation of a second valve. The risk of residual aortic regurgitation is consistent across valve designs and generations. (SWISS TAVI Registry; NCT01368250).

Keywords: balloon-expandable valve; left ventricular outflow tract calcium; mechanically expandable valve; self-expanding valve; transcatheter aortic valve replacement.