Managing the small aortic annulus in the era of increasing transcatheter aortic valve replacement explant surgery

Introduction

In the modern era, the evolution of annular enlargement techniques reflects the broader shift toward lifetime valve management, from initially avoiding patient-prosthesis mismatch (PPM) to enabling implantation of larger prostheses and facilitating future transcatheter valve interventions. The approach described by Yin et al. (1) represents a rational strategy to optimize prosthesis sizing, improve hemodynamic performance, and preserve future therapeutic options in patients with small annular anatomy. The report by Yin et al. highlights not only the challenge of prosthesis sizing after transcatheter aortic valve replacement (TAVR) explantation, but also a broader question: should surgeons focus solely on annular enlargement, or should they address the entire left ventricular outflow tract (LVOT) annular complex?

The management of severe aortic stenosis has evolved significantly over the past decade, with TAVR emerging as an increasingly utilized alternative to surgical aortic valve replacement (SAVR). As TAVR use continues to expand across broader patient populations, the number of TAVR explantations is also increasing. Despite its relatively low reported incidence (0.2% to 2.8%), TAVR explantation has become one of the fastest-growing procedures in the Society of Thoracic Surgeons (STS) Adult Cardiac Surgery Database (2). Moreover, TAVR explant surgery is associated with higher operative risk, with reported STS predicted risk of mortality (PROM) scores ranging from 3.9% to 9.9% (3). Among patients requiring intervention for aortic stenosis, those with a small aortic annulus represent a particularly challenging subgroup. The recent VIVA trial (4) comparing TAVR and SAVR in elderly patients with small aortic annuli demonstrated no significant differences in impaired valve hemodynamics, early clinical outcomes, or two-year rates of stroke and mortality between the two treatment strategies. These findings highlight an important consideration: small annulus anatomy does not clearly favor one approach over the other, emphasizing that treatment decisions should be individualized. In this context, strategies that incorporate collaborative surgical techniques, such as aortic annular enlargement (AAE) to create a more favorable platform for future transcatheter interventions, may become increasingly relevant.

The report by Yin et al. (1) provides an example of this evolving decision-making paradigm. This commentary examines the management strategy described by the authors in a reoperated patient with a small aortic annulus following prior TAVR. The authors present the case of a 74-year-old woman with a known bicuspid aortic valve who previously underwent TAVR with a 23-mm Sapien 3 valve two years earlier. She subsequently developed symptomatic severe aortic insufficiency due to a paravalvular leak, with elevated bioprosthetic valve gradients. Preoperative imaging demonstrated a small native aortic annulus measuring 19 mm. In this context, the authors advocate for SAVR with AAE using the Y-incision technique. This enlargement allowed implantation of a 25-mm bovine pericardial valve with a mean gradient of 7 mmHg postoperatively. This approach is presented as a safe, effective, and favorable alternative to other salvage options for prosthetic valve dysfunction after TAVR, particularly when compared with valve-in-valve TAVR or isolated SAVR without annular enlargement.

AAE strategies

Annular enlargement is indicated to prevent PPM in patients with small annular dimensions, particularly when the predicted indexed effective orifice area (EOA) is ≤0.85 cm²/m² (5). The most recent European Society of Cardiology/European Association of Cardiothoracic Surgery (ESC/EACTS) guidelines on valvular pathologies support annular enlargement in these settings to facilitate implantation of a larger prosthesis, thereby increasing EOA, reducing transvalvular gradients, and promoting regression of left ventricular hypertrophy to mitigate adverse outcomes associated with PPM (6). As the number of patients presenting with failed transcatheter valves continues to increase, surgical techniques that permit greater annular dimensions may play an increasingly important role in the management of this complex patient population.

One of the main concerns surrounding AAE is the potential for prolonged cardiopulmonary bypass and cross-clamp times, as well as increased perioperative morbidity and mortality compared with standard SAVR (7). Previous studies evaluating this topic have reported approximately 1.5-fold higher odds of perioperative mortality and slightly lower 30-day survival for SAVR with annular enlargement compared with SAVR alone (8). A Medicare-based analysis has therefore suggested that annular enlargement may be best reserved for patients at high risk of prosthesis–patient mismatch (8). Nevertheless, several surgical techniques have been described to achieve annular enlargement via anterior and posterior approaches, each offering varying degrees of annular expansion and technical complexity.

Studies have demonstrated that the aortic annular area may decrease substantially when smaller prostheses are implanted, with reductions approaching nearly half when a 23-mm valve is used without annular enlargement and approximately one-third when a 25-mm valve is implanted. In a study by Makkinejad et al., the median implanted valve size during conventional SAVR remained 23 mm, indicating that even when annular enlargement is performed, prosthesis size may remain limited in some cases (8). These limitations of conventional annular enlargement strategies have prompted the development of alternative approaches aimed at achieving more substantial annular expansion.

A more contemporary technique, the Y-incision technique, was introduced by Yang and colleagues in 2020 to maximize annular enlargement while avoiding division of the anterior mitral leaflet and to facilitate future valve-in-valve strategies. In this technique, a Y-shaped incision is created through the aortomitral curtain between the fibrous trigones, allowing placement of a rectangular patch to expand the annulus and LVOT (9). This approach permits implantation of significantly larger prostheses, often increasing valve size by two to three sizes, while also enlarging the sinuses of Valsalva and the sinotubular junction. By avoiding the extensive mitral leaflet incision required in the Manougian technique, the Y-incision approach preserves mitral valve integrity and reduces the risk of mitral dysfunction. Emerging data also suggest excellent hemodynamic performance with this technique, leading some centers to adopt it as a preferred approach to annular enlargement (8). These features make the Y-incision technique particularly attractive in patients with small annuli undergoing redo surgery after failed transcatheter valves, where maximizing prosthesis size becomes critical for both immediate hemodynamic performance and long-term valve management.

The primary limitation of the Y-incision technique remains the level of surgical expertise required, as the larger patch reconstruction can be technically demanding and may be associated with longer operative times. In addition, the Y-incision enlargement remains largely supravalvular and does not extend into the LVOT, which may predispose to tilting of the implanted valve. This limitation can be appreciated in the images provided by Yin et al., where the subannular region remains relatively narrow, while the supra-annular patch reconstruction expands the aortic root (1,10). This configuration may create an unfavorable geometry for valve implantation and can predispose to prosthetic tilt. Such an arrangement may impair optimal hemodynamic performance by failing to fully restore laminar LVOT flow, potentially compromising valve durability and limiting the feasibility of future valve-in-valve interventions. Nevertheless, recent data suggest that outcomes with the Y-incision technique remain comparable to other annular enlargement strategies in terms of procedural safety (8).

While the approach described by Yin et al. represents an elegant solution to the problem of prosthesis–patient mismatch, alternative enlargement strategies may address some of these geometric limitations. At our center, we have adopted a modified approach based on a double-patch extension of the Manouguian technique (10) to address some of these limitations. In this technique, the aortotomy is extended through the left non-commissure and carried beneath the annulus leftward toward the left fibrous trigone and rightward toward the right fibrous trigone, in a manner similar to the Y-incision concept (11). This technique achieves more extensive annular enlargement while allowing implantation of a larger prosthesis within the true annular plane.

An alternative strategy may also merit consideration. In reoperated patients with a small aortic annulus, the problem often extends beyond the failure of the prosthetic valve itself and may reflect an underlying pathology of the LVOT. In this setting, PPM should not be viewed solely as a valve problem, but rather as a manifestation of the entire LVOT–annular complex. Strategies that focus primarily on suprannular enlargement, such as the Y-incision technique, may therefore not fully address the underlying anatomic constraint if the obstruction involves the basal septum or subvalvular LVOT.

Therefore, in patients undergoing reoperation for PPM in the setting of a small annulus, a thorough evaluation of the LVOT anatomy should be performed prior to surgical intervention. Careful assessment of septal thickness and LVOT dimensions is essential to determine whether the primary limitation arises at the level of the basal annulus, the subvalvular septum, or the suprannular root. Identifying the true anatomic source of obstruction is critical in guiding the surgical strategy and ensuring that the intervention addresses the full extent of the pathology.

We have encountered a similar scenario in our experience involving a third redo operation for PPM, in which further evaluation revealed concomitant LVOT obstruction due to septal hypertrophy (12). In such cases, both the annular constraint and the subvalvular obstruction must be addressed during surgery to avoid persistent gradients, residual symptoms, and early reintervention. In this setting, annular enlargement alone may be insufficient to correct the underlying hemodynamic limitation.

For these reasons, in carefully selected redo patients with a small aortic annulus, consideration may also be given to combining annular enlargement with concomitant septal myectomy in order to achieve a more comprehensive relief of LVOT obstruction and optimize postoperative hemodynamics.

Conclusion

The management of failed transcatheter valves in patients with small aortic annuli presents a complex clinical challenge. In these patients, the problem may extend beyond prosthetic valve failure and instead reflect underlying limitations of the LVOT geometry. Careful preoperative assessment of septal thickness and LVOT dimensions is therefore essential. In selected cases, combining posterior annular enlargement with septal myectomy may be necessary to adequately address LVOT obstruction and prevent recurrent patient–prosthesis mismatch. As the number of patients with prior transcatheter valves continues to increase, collaborative surgical and transcatheter strategies will be essential in tailoring individualized treatment pathways for this complex patient population while maintaining both long-term therapeutic flexibility and favorable short-term hemodynamic performance.

Acknowledgments

None.

Footnote

Provenance and Peer Review: This article was commissioned by the editorial office, Journal of Visualized Surgery. The article has undergone external peer review.

Peer Review File: Available at https://jovs.amegroups.com/article/view/10.21037/jovs-2026-0038/prf

Funding: None.

Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://jovs.amegroups.com/article/view/10.21037/jovs-2026-0038/coif). The authors have no conflicts of interest to declare.

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References

1. Yin K, Titsworth M, Yokoyama Y, et al. Y-incision aortic annular enlargement after surgical explantation of transcatheter aortic valve bioprosthesis. Ann Cardiothorac Surg 2025;14:173-5.
2. Sá MP, Ashwat E, Jacquemyn X, et al. The current state of transcatheter aortic valve replacement explant: an updated systematic review. Ann Cardiothorac Surg 2025;14:85-97. [Crossref] [PubMed]
3. Razavi AA, Tam DY, Krishnan A, et al. Transcatheter Aortic Valve Explant Experience From a High-Volume Structural Heart Center. Ann Thorac Surg Short Rep 2026;4:601-6. [Crossref] [PubMed]
4. Rodés-Cabau J, Ribeiro HB, Mohammadi S, et al. Transcatheter or Surgical Aortic Valve Replacement in Patients With Severe Aortic Stenosis and Small Aortic Annulus: A Randomized Clinical Trial. Circulation 2024;149:644-55. [Crossref] [PubMed]
5. Talapaneni S, Ahmad D, Khandelwal M, et al. Prosthesis-Patient Mismatch Following Aortic Valve Replacement-A Comprehensive Review. J Clin Med 2025;14:8868.
6. Svensson LG, Adams DH, Bonow RO, et al. Aortic valve and ascending aorta guidelines for management and quality measures: executive summary. Ann Thorac Surg 2013;95:1491-505. [Crossref] [PubMed]
7. Makkinejad A, Monaghan K, Chen SA, et al. Aortic Annular Enlargement vs Isolated Aortic Valve Replacement in Patients With Matched Annulus. Ann Thorac Surg 2025;119:568-75. [Crossref] [PubMed]
8. Makkinejad A, Hua J, Hassler KR, et al. Comparison of the short-term outcomes between Y-incision aortic annular enlargement and traditional aortic annular enlargement techniques. Ann Cardiothorac Surg 2024;13:255-65. [Crossref] [PubMed]
9. Yang B. A novel simple technique to enlarge the aortic annulus by two valve sizes. JTCVS Tech 2021;5:13-6. [Crossref] [PubMed]
10. Manouguian S, Kirchhoff PG. Patch enlargement of the aortic and the mitral valve rings with aortic-mitral double-valve replacement. Ann Thorac Surg 1980;30:396-9. [Crossref] [PubMed]
11. Zaki A, Vargo P, Elgharably H. Revisiting the Manougian Technique With Double-Patch. November 18, 2025. doi:10.25373/ctsnet.30648722
12. Cekmecelioglu D, Smedira N, Elgharably H. Third-time redo aortic valve replacement with posterior annular enlargement and myectomy. Multimed Man Cardiothorac Surg 2025;2025: [Crossref] [PubMed]