Abstract 13182: Comparison of Actual and Theoretical Aortic Valve Calcium Score to Assess TAVR Referral Delay in Patients With Atrial Fibrillation

Introduction: Doppler mean gradient (MG) can underestimate the severity of aortic stenosis (AS) in patients with atrial fibrillation (AF) compared to patients in sinus rhythm (SR). Patients with AF and severe AS may experience delayed diagnosis and more advanced disease at time of referral for transcatheter aortic valve replacement (TAVR).

Methods: Patients who underwent TAVR from 2013 to 2017 for native valve severe AS were identified from an institutional database. MG and aortic valve calcium score (AVCS) at time of referral were compared in patients in AF and SR. Retrospective theoretical AVCS in AF patients were derived assuming an average progression of 152 AU/year (published data).

Results: There were 820 patients included; mean age was 81.3+/- 8.2 years and 41.6% were female. AF was present in 356 patients at time of referral. Patients in AF were older (82.2 vs. 80.5, p = 0.003), had lower MG compared to SR patients (42.0 vs. 44.9, p = 0.002) and a lower peak velocity (4.1 vs. 4.2, p = 0.010) with a similar indexed aortic valve area (0.4 vs. 0.4, p = 0.17). Stratified by sex, the median calcium score for AF patients was higher (by around 300 AU) among both males (AF 2850.0 vs. SR 2561.0, p = 0.044) and females (AF 1942.0 vs. 1610.5, p = 0.025) ( figure 1 ). A density plot of retrospective theoretical AVCS in AF patients (projected assuming referral to TAVR approximately two years prior) resulted in nearly identical median AVCS between the two cohorts ( figure 2 ).

Conclusions: Older age and higher AVCS in patients with AF compared to SR suggests that AS was both underestimated and more advanced at time of referral to TAVR. Patients in AF may have severe AS as early as 2 years prior to TAVR referral.