Incidence and Risk Assessment of Infolding Using Self-Expandable Devices in TAVR

Transcatheter aortic valve replacement is an evolving interventional therapy for patients with symptomatic severe aortic stenosis. Infolding (INF) as wrinkling along the valve frame is only seen in self-expandable transcatheter valves or surgical sutureless prostheses and is known to be a very rare event during delivery but probably underreported. Therefore, we aimed to (1) determine the frequency of events, (2) identify potential predictors of INF, and (3) evaluate the potential clinical impact of this adverse event.

INF cases of 2 centers were retrospectively analyzed in an all-comer cohort of 1416 patients with older- and newer-generation self-expandable (SEV) devices. The underlying functional, anatomical, and procedural conditions were evaluated by univariate analysis.

INF+ was observed in 14 patients (1.0%) with the following valve size distribution: SEV-26: 14.3%, SEV-29: 28.6%, and SEV-34: 57.4%. Several dependent predictors of INF were pointed out, such as severe peripheral kinking, severe aortic calcification, resheathing maneuvers, valve-in-valve procedures, and the use of the largest valve size. INF+ patients showed a higher incidence of acute kidney injury (INF- vs. INF+: 12.3% vs. 35.7%; p = 0.008), of a new atrioventricular block (INF- vs. INF+: 14.8% vs. 42.9%; p = 0.003), and a higher need of permanent pacemaker implantation (INF- vs. INF+: 14.9% vs. 35.7%; p = 0.031).

Identifying potential predictors of INF can probably influence the implantation strategy and improve safety algorithms and clinical outcomes. Even being a rare but potentially life-threatening and underreported event, safety rules must be established when expanding transcatheter aortic valve replacement treatment to younger patients.