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Novotny et al. Vessel Plus 2022;6:51 https://dx.doi.org/10.20517/2574-1209.2021.139 Page 7 of 15

As overall comorbidity complexity scores, the Elixhauser summary indices were not different for r-SAVR
patients with and without pre-operative AF/AFL (Elixhauser Mortality Index: 15.14 ± 11.02 vs. 12.47 ± 11.16,
P = 0.090; Elixhauser Readmission Index: 23.67 ± 14.68 vs. 21.13 ± 14.49, P = 0.220). Similarly, viv-TAVR
patients with AF/AFL+ versus AF/AFL- had no difference in their Elixhauser summary indices (Elixhauser
Mortality Index: 15.43 ± 10.61 vs. 13.45 ± 10.48, P = 0.289; Elixhauser Readmission Index: 30.43 ± 15.45 vs.
30.61 ± 15.87, P = 0.949).

Outcomes following repeat AVR
Repeat AVR outcomes are described in Table 2. Study endpoints were evaluated in the r-SAVR and viv-
TAVR cohorts [Figure 2]. Rates of the main study endpoints were similar for patients with AF/AFL
compared to those without after r-SAVR (STS composite endpoint: 24.1% vs. 14.4%, P = 0.076; 30-day
readmission: 19.5% vs. 14.4%, P = 0.329) and viv-TAVR (STS composite endpoint: 18.5% vs. 15.6%, P =
0.668; 30-day readmission: 15.4% vs. 9.4%, P = 0.301). Of all r-AVR procedures, the AF/AFL+ versus
AF/AFL-patients had no differences identified for the MM composite (21.7% vs. 14.8%, P = 0.103) and for
30-day READMIT (17.8% vs. 12.6%, P = 0.191). Across all r-SAVR outcomes evaluated, the AF/AFL+
patients had increased rates of prolonged ventilation (10.3% vs. 2.5%, P = 0.031) and cardiac arrest (14.9% vs.
5.1%, P = 0.016). Additionally, r-SAVR patients with AF/AFL had significantly increased post-operative
days (12.74 ± 11.23 vs. 9.31 ± 8.05, P = 0.017). Viv-TAVR patients with and without AF/AFL had similar
rates of clinical and resource utilization outcomes. Univariate analysis results for 30-day readmission and
the composite endpoint are described in Supplementary Tables 3 and 4.

Multivariable modeling for preoperative atrial fibrillation
To understand the nature of the r-AVR patient population presenting with AF/AFL, a multivariable model
was built to identify the other patient characteristics associated with preoperative AF/AFL risk. The
multivariable model’s patient characteristics identified to be associated with presence of preoperative
AF/AFL included older age (OR, 95%CI: 1.03, 1.01-1.05, P = 0.017), along with no documented history of
cerebrovascular disease (OR, 95%CI: 0.44, 0.23-0.86, P = 0.017) or prior pacemaker or implantable cardiac
defibrillator (OR, 95%CI: 0.45, 0.22-0.92, P = 0.029); this model’s c-index was 0.729 and Hosmer-Lemeshow
test statistic P-value = 0.0617 (indicating no lack of model fit).

Multivariable modeling for primary study outcomes
The impact of AF/AFL on the STS composite endpoint was evaluated while holding other variables constant
[Table 3]. This final model had a C-index of 0.753. Presence of pre-operative AF/AFL did not significantly
impact odds of the composite (OR, 95%CI: 1.23, 0.66-2.28, P = 0.512). Other predictors of the composite
endpoint included black race (OR, 95%CI: 2.89, 1.01-8.32, P = 0.049) and Elixhauser mortality score (OR,
95%CI: 1.07, 1.04-1.10, P < 0.0001).

For 30-day readmission, the impact of AF/AFL was evaluated holding other model-eligible variables
constant [Table 4]. For this 30-day readmission model, the model had a c-index of 0.682. Pre-operative
AF/AFL did not affect odds of 30-day readmission (OR, 95%CI: 1.15, 0.60-2.19, P = 0.681). However, history
of cerebrovascular disease predicted 30-day readmission (OR, 95%CI: 2.54, 1.23-5.25, P = 0.012);
additionally, viv-TAVR compared to r-SAVR procedures were protective against 30-day readmission (OR,
95%CI: 0.44, 0.21-0.91, P = 0.027).

As sensitivity analyses, the multivariable model built predicting the likelihood of patients incurring
preoperative AF/AFL was added to the co-primary endpoint models built for the composite endpoint and
for 30-day readmission [Supplementary Tables 5 and 6]. As these propensity scores did not substantially
alter this study’s co-primary models’ findings, the current study conclusions should be considered robust.