Importance of Contrast Aortography With Lotus Transcatheter Aortic Valve Replacement: A Post Hoc Analysis From the RESPOND Post-Market Study.

Objectives: The aim of this post hoc analysis from the RESPOND (Repositionable Lotus Valve System-Post-Market Evaluation of Real World Clinical Outcomes) post-market study was to assess the final implantation depth on the contrast aortogram after Lotus valve (Boston Scientific, Marlborough, Massachusetts) transcatheter aortic valve replacement (TAVR) and to correlate with permanent pacemaker implantation (PPI) and paravalvular leak (PVL).

Background: Contrast aortography allows for the assessment of implantation depth and PVL during and after TAVR. Previous reports suggested an association between final device position and rates of PPI and PVL.

Methods: The RESPOND study was a prospective, open-label, single-arm study in 41 centers evaluating outcomes after Lotus TAVR in routine clinical practice. Aortograms were collected at the Erasmus Medical Center and analyzed by researchers who were blinded to clinical outcomes. The primary analysis correlated implantation depth with PPI and PVL and required aortograms in a coaxial projection. The relation between implantation depth and need for PPI was assessed by multivariate logistic regression, adjusting for pre-defined confounders. A secondary analysis compared PVL analysis by contrast aortography with transthoracic echocardiography (TTE) performed by the independent core laboratory.

Results: A total of 724 angiographic studies were included in this analysis. Mean Lotus implantation depth was 6.67 ± 2.19 mm. The overall PPI rate was 35%. PPI rate was lower with shallow implants (<6.5 mm: 21% vs. ≥6.5 mm: 41%; p < 0.001). After adjustment for confounders, implantation depth independently predicted need for PPI (odds ratio per 1-mm increment in depth: 1.200; 95% confidence interval: 1.091 to 1.319; p = 0.002). More than trivial PVL was present in 23% by contrast aortography and in 8% by TTE. Implantation depth was not correlated with PVL by contrast aortography or TTE (p = 0.342 and p = 0.149, respectively). PVL grading by contrast aortography and TTE was concordant in 77%.

Conclusions: In this post hoc analysis of the RESPOND study PPI was highly correlated with implantation depth, whereas PVL was not. Higher Lotus implantation may reduce need for PPI.