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Dokko et al. Vessel Plus 2022;6:53 https://dx.doi.org/10.20517/2574-1209.2022.11 Page 3 of 15

reports were received by the study team, the Stony Brook University Committee on Research in Human
Subjects provided a “not human study research” written exemption [IRBNet #: IRB2021-00605 - POAF
r-AVR] on November 23, 2021.

As this investigation’s procedure of interest, repeat aortic valve procedures were defined as a second SAVR
or TAVR that occurred at least 30 days after their first SAVR or TAVR operation. Based on patients’ r-AVR
procedure date, all encounters occurring within 30-day of discharge were recorded; 30-day readmissions
and repeat procedures were identified. Duplicate records and patients without unique personal identifiers or
gender information were excluded. Given the inherently higher risk of complications, patients with
endocarditis, thoracic aortic aneurysms with or without dissection, coronary artery bypass grafting,
percutaneous coronary intervention, mitral valve repair or replacement, metastatic cancer, any solid tumor
without metastasis, or r-AVR procedures with concomitant coronary artery bypass grafting procedure were
excluded. To identify patients with new-onset POAF/AFL, patients with a history of atrial fibrillation or
flutter, Maze procedure, pacemaker implantation or defibrillation two years prior to their first AVR
operation and r-AVR operation were excluded. The flow diagram of our patient population selection is
shown in [Figure 1]. After identifying all r-AVR patients who met the inclusion and exclusion criteria,
r-SAVR and ViV-TAVR patients were separately compared according to POAF/AFL status as shown in
[Tables 1 and 2].

Outcome measures
For this study, the co-primary outcomes included predictors of new-onset postoperative atrial fibrillation
and/or atrial flutter (POAF/AFL), outcomes of r-AVR patients with POAF/AFL, and predictors of a
combined mortality and morbidity composite endpoint (MM), and an indicator of 30-day hospital
readmission (READMIT). Based on the Society of Thoracic Surgeons’ (STS) standardized national Adult
Cardiac Surgery Database reports’ short-term outcomes, this study’s primary MM composite endpoint was
comprised of 30-day operative mortality (i.e., either a death in-hospital or within 30 days) or any major
morbidity (based upon any the following events occurring: new perioperative stroke, new renal failure
requiring dialysis, extended post-procedural ventilator use, deep sternal wound infection, and/or repeat
cardiac procedure) as shown in [Table 3].

This study’s secondary outcomes included conversion rates (i.e., ViV-TAVR conversion to r-SAVR), all the
primary MM composite’s sub-components (i.e., in-hospital death, 30-day death, new perioperative stroke,
new renal failure requiring dialysis, extended post-procedural ventilator use, deep sternal wound infection,
and/or repeat cardiac procedure), as well as other resource consumption metrics (e.g., total length of stay
(LOS), postoperative length of stay (PLOS), and 30-day emergency department visit). Tertiary outcomes
included other procedural SAVR/TAVR complications such as acute kidney injury, cardiac arrest, major
bleeding, prosthetic valve endocarditis, transient ischemia attack, vascular complications, and myocardial
infarction.

To distinguish between procedural complications and patient comorbidities, postoperative complications
were defined when patients had no prior history of the complication-related diagnosis within the 2-year
period prior to their r-AVR procedure. Based on the “new onset” POAF/AFL definition, therefore, no study
patients had preoperative atrial fibrillation or atrial flutter.

Statistical analysis
All analyses were performed using SAS 9.4 (SAS Institute, Inc., Cary, NC). Chi-square tests with exact
P-value from Monte Carlo simulation were used for categorical variables and Welch’s t-test was used for
continuous variables. In the context of the literature, bivariate comparisons were used to screen (P < 0.10)