Todd, Austin

Abstract Objectives This study examined the indications, frequency, and outcomes of cardiac surgery following transcatheter aortic valve replacement (TAVR) at a single institution. As TAVR volumes increase, understanding the nature and outcomes of subsequent cardiac operations is critical, particularly as the procedure expands to younger, lower-risk populations. Methods We analysed outcomes of 61 patients who underwent cardiac surgery after TAVR at our institution from August 2011 to September 2023, excluding periprocedural complications and staged procedures. Patients were stratified into 2 groups: those requiring surgical aortic valve replacement (SAVR) with or without concomitant procedures (n = 33) and those undergoing non-SAVR cardiac operations (n = 28). Data were collected from a prospectively maintained cardiovascular surgery database and electronic health records. Indications for surgery, operative characteristics, and outcomes were analysed, with survival assessed using Kaplan-Meier estimates. Results The median interval between TAVR and cardiac surgery was 19 months. Indications for SAVR included infective endocarditis (36%), non-structural valve deterioration (36%), structural valve deterioration (12%), and valve thrombosis (6%). Non-SAVR operations primarily addressed mitral valve disease (43%) and coronary artery disease (29%). Operative mortality was 6.6%, with no deaths in the endocarditis subgroup. Postoperative complications included prolonged mechanical ventilation (18%), new-onset renal failure (7%), and stroke (2%). Kaplan-Meier survival estimates were 83% at 1 year and 50% at 5 years. Conclusions Although complex, cardiac operations in patients who have undergone TAVR can be performed with acceptable mortality rates. Structural valve deterioration, paravalvular leak, and endocarditis were the primary indications for SAVR, while mitral valve and coronary artery disease predominated in non-SAVR cases. These findings highlight the importance of considering nonaortic valve pathologies in TAVR planning, particularly as the procedure expands to younger, lower-risk populations.

Background: Valve-in-valve transcatheter aortic valve replacement (ViV-TAVR) is an increasingly preferred strategy for managing failed surgical bioprosthetic valves, especially in high-risk patients. However, limited data exist comparing outcomes between balloon-expandable (BE) and self-expandable (SE) transcatheter heart valves (THVs) in this setting. The influence of aortic annular area on outcomes by valve type remains poorly understood. This study evaluated the impact of annular area on clinical outcomes following ViV-TAVR with BE vs. SE valves. Methods: We conducted a retrospective, single-center analysis of 353 patients who underwent ViV-TAVR between 2012 and 2024. All had prior surgical bioprosthetic AVR and received either BE (n=267) or SE (n=86) valves. Preprocedural multidetector CT was used to quantify aortic annular area. Transthoracic echocardiography was performed before and after the procedure to assess transvalvular gradients and hemodynamics. The primary endpoint was all-cause mortality. Penalized spline regression was used to model the nonlinear relationship between annular area and mortality and assess interaction by valve type. Results: Median age was 79 (IQR: 72–83) in the BE group and 80 (IQR: 76–85) in the SE group (p=0.07). Female sex was more common in the SE group (32% vs. 22%, p=0.047). Median annular area was 374 mm2 (IQR: 316–440) for BE and 365 mm2 (IQR: 308–432) for SE (p=0.081). Preprocedural gradient and effective orifice area index were 36 mm Hg (IQR: 28–46) and 0.6 cm2/m2 (IQR: 0.5–0.9), respectively, with no significant differences. Median hospital stay was 2 vs. 3 days (p=0.68). Thirty-day mortality was low (1 per group, p=0.36). Median follow-up was 4.0 years (IQR: 1.6–6.4). One- and 5-year survival rates were 94.75% and 61.7%, respectively (p=0.20). Penalized spline analysis showed a nonlinear association between annular area and mortality. The hazard ratio for BE valves declined with increasing annular area and fell below SE valves beyond ~400 mm2. Conclusion: ViV-TAVR is a safe and effective treatment for failed surgical bioprostheses. Smaller annular areas were associated with higher mortality. Outcomes with BE valves improved in larger annuli, suggesting annular area could guide valve selection. Further studies are warranted to validate these observations.

Background Postoperative atrial fibrillation occurs in ~40% after cardiac surgery. Mineralocorticoid receptor antagonists (MRA) are known to reduce chronic atrial fibrillation (AF) development and burden. We evaluated the association of preoperative MRA use with postoperative atrial fibrillation and investigated atrial cell types modulated by MRAs during cold preservation. Methods We studied 19 042 cardiac surgery patients at Mayo Clinic. Propensity 1:3 matching identified 298 MRA users and 894 non‐users. A subgroup analysis of patients on any preoperative diuretic was performed to isolate cardiac‐specific effects of MRAs, matching 298 MRA users to 894 non‐MRA diuretic users. AF recurrence was assessed for up to 6‐years. Single‐nucleus RNA sequencing (snRNA‐seq) was performed on human donor atria exposed to canrenone (a water‐soluble MRA) during cold preservation with ex‐vivo reperfusion, and expression profiles were compared with atria from patients with AF. Results After matching, preoperative MRA use was associated with a lower incidence of postoperative atrial fibrillation (19.8% versus 31.8%, P <0.001). In the diuretic‐only subgroup, MRA users also had lower postoperative atrial fibrillation (19.8% versus 33.2%, P <0.001). MRA use was associated with a reduced incidence of paroxysmal and chronic AF at 6‐years. snRNA‐seq identified a cardiomyocyte subpopulation, CM2, with high mineralocorticoid receptor expression where canrenone suppressed cold preservation‐induced mineralocorticoid receptor target gene expression, which was conversely elevated in chronic AF. Canrenone also attenuated stress‐response in atrial macrophages and pericytes. Conclusions Preoperative MRAs were associated with reduced postoperative and long‐term AF after cardiac surgery. Mechanistically, our ex‐vivo human atrial model revealed that MRAs suppress mineralocorticoid receptor ‐driven atrial stress responses, particularly in conduction‐relevant cardiomyocytes.