Early surgical outcomes of rapid deployment aortic valve replacement in bicuspid aortic valves

Introduction

Sutureless and rapid-deployment valves have emerged over the past decade as viable treatment options for patients requiring surgical aortic valve replacement (AVR) due to aortic stenosis. The use of biological valve prostheses in sutureless, rapid-deployment AVR (RD AVR) procedures has yielded excellent outcomes, establishing it as a safe and effective treatment alternative for individuals with severe aortic valve stenosis (1).

A decrease in procedural times has been demonstrated with RD AVR using the Intuity Elite (Edwards Lifesciences, Irvine, CA, USA), making minimally invasive approaches easier and simplifying valve implantation under complex anatomical conditions when compared with conventional AVR (2). This prosthetic valve has also demonstrated superior hemodynamic performance to conventional aortic bioprostheses (2). Another study revealed that RD AVR leads to shorter aortic cross-clamp (ACC) and cardiopulmonary bypass (CPB) times than standard AVR, particularly in patients undergoing concurrent procedures (3). This enables the use of larger prostheses and results in reduced transvalvular gradients and an increased indexed effective orifice area compared with standard AVR. Consequently, RD AVR may provide a solution to patient-prosthesis mismatch in certain cases.

However, these studies (2,3) did not provide specific surgical outcomes for bicuspid aortic valve (BAV) or recommend RD AVR implementation since they completely excluded Sievers (4) type 0 bicuspid cases. The implantation of a rapid-deployment valve is currently discouraged and not recommended in patients with BAV, particularly those with Sievers type 0 anatomy (5,6). BAV is more elliptical in an annular shape and exhibits asymmetry in the sinus of Valsalva. Furthermore, the positioning of the commissures and annulus height differs from that of the tricuspid aortic valve (TAV), and the raphe is present. Therefore, because the Intuity Elite valve for RD AVR is primarily designed based on TAV, performing RD AVR in patients with BAV may raise concerns and must be approached cautiously. A favorable review article (7) on RD AVR in BAV exists, although it did not specifically mention the Sievers type 0.

Moreover, the existing literature comparing the clinical and hemodynamic outcomes of patients with BAV and those with TAV after RD AVR is limited (8-13). Therefore, this single-center, retrospective observational cohort study aimed to describe the postoperative outcomes and complications of patients with BAV (including Sievers type 0) treated with RD AVR compared with those of patients with TAV. We present this article in accordance with the STROBE reporting checklist (available at https://jtd.amegroups.com/article/view/10.21037/jtd-23-1942/rc).

Methods

Patients selection

RD AVR practice using Intuity valves was officially initiated at Seoul St. Mary’s Hospital in September 2022. We retrospectively analyzed the medical records of 80 patients who underwent AVR between September 1, 2022, and July 31, 2023. Of the 80 patients who underwent AVR, 16 were excluded because they received mechanical prosthetic valves, leaving 64 patients. The choice between tissue and mechanical valves was made in consultation with the patient, taking into account their age and preferences. After excluding 34 conventional tissue valve cases, 30 RD AVR cases were analyzed (Figure 1). RD AVR was preferred for patients with aortic stenosis as the primary pathology, small aortic annulus (less than 21 mm on computed tomography), severe aortic annulus calcification, concomitant cardiac surgery, or other factors indicating high surgical risk (14). Individuals presenting with aortic regurgitation as the primary condition or exhibiting severe calcification in the left ventricular outflow tract (LVOT) were not considered candidates for RD AVR. Surgeon preference also played a role in this decision.

Figure 1 Patient selection diagram. AVR, aortic valve replacement; RD AVR, rapid-deployment aortic valve replacement.

Surgical techniques

All RD AVR procedures were performed using an Edwards Intuity Elite (model 8300AB; Edwards Lifesciences) rapid-deployment valve system. All surgeries were performed using median sternotomy, given our initial experience with RD AVR. Depending on the need for concomitant surgery and the patient’s characteristics, cavoatrial or bicaval CPB was initiated. Following aortotomy, we extracted the impaired aortic valve and performed complete decalcification, aiming to improve accommodation with the implanted prosthesis, minimize the risk of paravalvular leakage, and establish a more accurate sizing standard.

The placement of the conventional three guiding stitches (simple, double-armed, and braided 2-0 sutures) was determined using the valve sizers provided (Figure 2). Care was taken to position the three struts of the prosthetic valve away from the coronary orifices whenever possible. Additional stitches, usually about three, were applied between the three guiding stitches, spaced at 120° intervals, as required. In this process, the stitches may not necessarily pass through only the nadir but can vary in position, particularly in Sievers type 0 bicuspid cases, depending on the shape of the patient’s aortic annulus (Figure 3). We aimed to equalize the heights of the annular planes and ensure uniform seating of the inflow ring of the Intuity valve across the entire annulus to prevent misplacement. Additional stitches were necessary to ensure annular circularity and uniform height along the annular plane. The needle that passed through the annulus was also removed. Once the guiding sutures were set, a valve sizer was used to verify uniform spacing, and the complementary needle of the suture was subsequently passed through the sewing cuff of the Intuity valve. Next, the valve was parachuted toward the annulus using suture guides. Several stiff tourniquets are used to secure the guiding sutures. While deploying a prosthetic valve, focusing on the orientation of the valve holder and guiding the stitch tension is important to ensure that the valve remains perpendicular to the annular plane. Before or after inflating the balloon to expand the sealing frame, if necessary, a 5-mm scope was inserted through the central hole to confirm the proper positioning of the balloon-expandable skirt within the LVOT. Finally, the holding sutures were tied using an automated suture-fastening device, and we confirmed the absence of paravalvular leakage using normal saline.

Figure 2 Rapid-deployment aortic valve replacement in a patient with a Sievers type 0 bicuspid aortic valve. (A) After marking the position of the coronary ostium, the decision regarding where to place the three guiding stitches is determined using a valve sizer. Additionally, three more stitches are added between the three guiding stitches, each separated by a 120° interval. (B) Conventional guiding sutures are placed at the sewing cuff of the Intuity valve, and the needles of these additional stitches are passed through the sewing cuff below the three struts. (C) After the Intuity valve is parachuted along the guide sutures down to the annulus, a total of six sutures are secured using stiff tourniquets. (D) The 5-mm scope is introduced through the center hole after the balloon catheter is detached from the valve holder. (E) The sealing frame is checked using the 5-mm scope before and after inflating the balloon. (F) Finally, normal saline was used to detect the presence of paravalvular leakage.

Figure 3 Schematic representation of a rapid-deployment aortic valve replacement in a patient with a Sievers type 0 bicuspid aortic valve. Traditional three guiding stitches (indicated by white arrowheads) are positioned 120° apart from each other. Two stitches are positioned below each coronary ostium, and one suture is applied at the lowest point of another sinus. Additional three stitches (indicated by white arrows) are necessary to ensure the annular circularity and uniform heights along the annular plane. A, anterior; P, posterior; R, right; L, left.

Study outcomes

The primary outcome was postoperative paravalvular regurgitation, while the secondary outcomes were transvalvular pressure gradients and pre-discharge pacemaker implants. Overall clinical outcomes, including surgical time, valve size, hospital stay, stroke, and 30-day mortality, were also analyzed.

The risk of early postoperative mortality was assessed using the European System for Cardiac Operative Risk Evaluation (EuroSCORE) II (15) and the Society of Thoracic Surgeons 30-day Predicted Risk of Mortality score (STS PROM) (16). Transthoracic echocardiography was performed in all patients before discharge from the hospital. Postoperative paravalvular leakage was defined as reaching a grade of mild or higher on postoperative echocardiography (17).

This study was conducted in accordance with the principle of the Declaration of Helsinki (as revised in 2013). The Institutional Review Board (IRB) of Seoul St. Mary’s Hospital reviewed and approved this study’s protocol (IRB No. KC23RISI0665), and the requirement for informed consent was waived due to its retrospective nature.

Statistical analysis

Continuous variables were expressed as means and standard deviations, while categorical variables were presented as counts and percentages. Group comparisons involved the use of independent-sample t-tests or Mann-Whitney U tests for continuous variables and Chi-squared or Fisher’s exact tests for categorical variables. All statistical analyses were performed using R (R 4.3.2; The R Foundation for Statistical Computing, Vienna, Austria), with statistical significance set at a two-sided P value of <0.05.

Results

Baseline characteristics

No patient had undergone previous cardiac surgery. Among the 30 patients, 16 and 14 were diagnosed with TAV (group A) and BAV (group B), respectively (Figure 1). No statistically significant differences were observed between the groups regarding sex, age, or baseline conditions (Table 1). However, the mean body surface area value was significantly higher in group B than in group A (1.59±0.10 vs. 1.69±0.12 m², P=0.02). Although EuroSCORE II did not significantly differ between both groups, STS PROM was higher in group A than in group B (2.08±1.49 vs. 2.36±1.67, P=0.62 and 2.24±1.29 vs. 1.27±0.56, P=0.01, respectively).

Clinical outcomes

Table 2 presents the operative data. A tendency for more concomitant aortic surgeries was found in patients from group B than in those from group A, without a significant difference (6.3% vs. 35.7%, P=0.07). A significant difference was found between group A and group B in the insertion of larger-sized valves (20.62±1.82 vs. 22.86±2.28 mm, P=0.006). Additionally, the CPB and ACC times were significantly longer in group B than in group A (151.64±21.97 vs. 126.81±22.49 min, P=0.005 and 111.21±20.33 vs. 90.75±16.32 min, P=0.005, respectively).

The postoperative results are outlined in Table 3. No paravalvular leakage was observed in any patient on postoperative transthoracic echocardiography performed before discharge. Patients with TAV exhibited higher mean and peak pressure gradients than those with BAV (16.26±5.49 vs. 12.20±4.64 mmHg, P=0.03 and 28.65±8.31 vs. 22.05±8.35 mmHg, P=0.03, respectively). Regarding permanent pacemaker implantation (PPI) during hospitalization, only one (7.1%) case occurred in group B (P=0.46). However, stroke and 30-day mortality were not found in any of the patients. The mean intensive care unit stay was 3.50 and 1.44 days in groups B and A, respectively (P=0.09). No significant difference was found between the two groups in the length of hospital stay (9.94±4.81 vs. 11.86±9.71 days, P=0.49).

Secondary analysis

The outcomes of the patients in group B were analyzed and stratified into two subgroups based on the bicuspid anatomy. Among the 14 patients with BAV in group B, six classified as having true BAV (Sievers type 0) and eight classified as Sievers type 1 were categorized into groups B0 and B1, respectively. The clinical outcomes of the six participants in group B0 were assessed and compared with those of the eight individuals in group B1. Table S1 presents the baseline characteristics of the patients.

No significant difference was found in the prosthetic valve size between the two groups (22.75±1.98 vs. 23.00±2.83 mm, P=0.84) (Table S2). However, the CPB and ACC times were significantly longer in group B0 than in group B1 (169.50±20.92 vs. 138.25±10.28 min, P=0.003 and 129.83±15.84 vs. 97.25±8.28 min, P<0.001, respectively). Concomitant aortic surgery was performed in four (66.7%) and one (12.5%) case in groups B0 and B1, respectively (P=0.09).

Furthermore, no significant differences were observed in the echocardiographic findings, including transvalvular pressure gradients, between the two groups (Table S3). None among the six patients with Sievers type 0 BAV required PPI.

Discussion

Surgical AVR procedures have become easier with the Intuity valve system, leading to significantly shorter ACC and CPB times while ensuring excellent survival rates and improved valvular hemodynamic function (8,9). RD AVR, which has a balloon-expandable frame positioned in the subvalvular area of the LVOT, helps reduce blood flow turbulence (18). Consequently, it is considered advantageous in terms of hemodynamic performance even in patients with a small aortic root (19).

Patients who underwent RD AVR received larger prostheses despite sharing similar characteristics with those who underwent conventional AVR, leading to reduced pressure gradients and an improved indexed effective orifice area (3). This is particularly crucial for patients with smaller aortic roots. Compared to conventional AVR, which typically requires smaller prostheses, RD AVR does not require pledgeted sutures, which causes surgeons to select larger prostheses in borderline cases.

Although mortality and paravalvular regurgitation rates are similar when comparing sutureless or rapid-deployment valves for AVR to conventionally stented bioprosthetic valves, advantages and disadvantages might exist due to a higher PPI incidence (12). Typically, the reported PPI rates range from 3% to 8% for conventional surgical AVR (20). In transcatheter AVR cases, the reported PPI rate ranges from approximately 6.5% to 17.4% (21,22), and for bicuspid cases specifically, it is known to be in the range of 6.1% to 15.1% (23,24). This elevated occurrence of PPI in transcatheter AVR cases is reportedly believed to result from the conduction system’s compression due to expanding the bioprosthetic valve device without removing the calcified native valve (25). Sutureless AVR using the Perceval valve (LivaNova PLC, London, United Kingdom) reportedly has a high PPI rate of up to 23% (26). The PPI incidence ranged from approximately 5% to 13.6% following RD AVR using the Intuity valve system (9-11,13). In this study, among a total of 30 patients who underwent RD AVR, there was one case of PPI (3.3%).

However, most of the abovementioned study outcomes (8-13) did not encompass or acknowledge patients with BAV, and bicuspid valves were not referenced. The application of sutureless and rapid-deployment prostheses may be avoided in individuals with BAV because of anatomical concerns and the increased risk of paravalvular leaks. Additionally, the application of an extra guiding suture to a larger sinus, such as the noncoronary sinus, has been documented (5). However, according to Coti et al. (5) performing this procedure in high-volume centers is advisable for BAV cases. In cases of Sievers 0 BAV, where an abnormal origin of both coronary arteries from a single cusp is observed, an increased risk of coronary obstruction exists, leading to the avoidance of using the Intuity valve.

Some studies (5,6) involving patients with BAV for RD AVR have shown that moderate-to-severe paravalvular regurgitation occurs in >3% of cases, with a reported PPI incidence exceeding 9%. However, the number of patients with Sievers type 0 is minimal, and RD AVR is not recommended for patients with Sievers type 0 BAV. Additionally, a favorably inclined review article (7) on RD AVR in BAV did not specifically mention Sievers type 0.

Some reports (27,28) have suggested that patients with Sievers type 0 BAV are unsuitable candidates for RD AVR. A modified implant technique has been introduced in the case of a sutureless Perceval valve, focusing on Sievers type 0 BAV (29). Therefore, the significance lies in sharing our successful experience using RD AVR without any instances of paravalvular leakage, even in patients with type 0 BAV. However, short-term data on RD AVR technologies in patients with BAV, particularly Sievers type 0, are lacking, necessitating ongoing research.

Typically, the Intuity Elite valve requires three conventional guiding sutures to be placed at the nadir. However, in our study, we included additional stitches and used a scope pre- and post-balloon inflation to confirm the balloon-expandable frame and LVOT, potentially lengthening the surgical time. The meticulous choice of locations for additional sutures and the evaluation of diverse anatomical factors, such as the coronary ostia, aimed to prevent complications, including valve malposition, leakage, and coronary obstruction. Furthermore, the attempt to use an oversized strategy to address the uneven or small annulus was avoided to prevent the potential risk of pacemaker insertion.

According to Barnhart et al. (11), the mean ACC and CPB times were reported as 49.3±26.9 and 69.2±34.7 min, respectively, for full sternotomy in isolated RDAVR procedures and 63.1±25.4 and 84.6±33.5 min, respectively, for minimally invasive approaches. Although they did not mention patients with BAV, our procedure took longer for AVR than that in the abovementioned study, given our initial experience, the higher number of patients with BAV, and the ratio of concomitant surgeries.

Given our institution’s low volume of cardiac surgery and early experience, we focused more on achieving superior hemodynamic outcomes when performing RD AVR than on its advantages, such as reduced procedural times or enabling minimally invasive approaches. A report (30) indicated that although RD AVR shows low rates of postoperative regurgitation, the incidence remains higher than that of conventional AVR. However, our study did not find any cases of paravalvular regurgitation despite the higher proportion of patients with BAV. Therefore, we expect better surgical outcomes over time with increasing experience in our institution, akin to the findings in the report by Berretta et al. (31).

Reviewing the surgical risk profile of the patients in this study, the average value indicates a low-risk scenario. It is worth mentioning that in our institution’s multidisciplinary discussions on the treatment strategy for aortic stenosis, patients predominantly classified as low surgical risk frequently choose surgical aortic valve replacement.

Coti et al. (5) reported that the rate of aortic surgery among patients with BAV was 22.4%, surpassing the 4.2% rate observed in the TAV group (P<0.001). Our data showed that aortic surgery was necessary in five (35.7%) patients in the BAV group. Since these cases involved concurrent aortic surgery, this emphasizes the continued requirement for careful consideration when surgically managing patients with BAV. Therefore, investigating the outcomes of surgical AVR in patients with Sievers type 0 BAV remains an ongoing and important issue.

This study had some limitations. Not being a prospective, randomized controlled clinical trial, there is a potential for selection bias in this study. When adopting a new procedure, the early experience involves some level of surgeon preference in patient selection. The population size was limited, resulting in small sample sizes for the TAV and BAV groups, leading to heterogeneity. Therefore, conducting a statistical comparison between the two groups might substantially reduce statistical significance. This study’s clinical significance lies in the experience of RD AVR in patients with BAV from a single institution perspective rather than categorizing its article as a comparative study. It also provides insights into the surgical techniques for patients with Sievers type 0 BAV. The purpose of performing subgroup analysis is not to discover additional statistical significance but to present the pre- and postoperative data separately for type 0 bicuspid patients and other bicuspid patients, aiming to demonstrate their distinct characteristics.

We focused on the early postoperative echocardiographic outcomes in our clinical analysis and did not include the details regarding late complications, quality of life, or long-term hemodynamic performance. According to Berretta et al. (13), the pressure gradient within the Intuity valve decreases as the valve size increases. Therefore, considering this characteristic of the valve size in our study results is necessary. Because larger prosthetic valve sizes were used in patients with BAV, a more extensive study involving a larger patient cohort is required.

Our study population has a limitation stemming from the limited number of patients with BAV, which was somewhat influenced by the prevalence of BAV. However, among the 30 RD AVR cases, 14 (46.67%) were BAV, indicating a substantially higher ratio. Although the general population has a relatively low BAV prevalence, ranging from approximately 1% to 2% (32), this pattern where a relatively greater number of patients with BAV are inclined toward surgical AVR rather than transcatheter AVR emerged from our multidisciplinary discussions involving patients with severe aortic stenosis.

Concerns regarding RD AVR can stem from elliptical annuli rather than circular annuli, incomplete prosthesis expansion, asymmetric calcification, and suboptimal alignment in BAV, particularly in Sievers type 0. However, based on our experience, conducting RD AVR might face fewer difficulties in scenarios where bicuspid valve anatomies exhibit a round aortic annulus and uniform commissure height. Therefore, exercising caution is necessary when using a valve sizer to mark the placement of guiding stitches to prevent coronary obstruction by any of the prosthesis commissural posts. Furthermore, safely performing RD AVR was feasible even in cases of Sievers type 0 BAV, ensuring no paravalvular leakage, albeit with a slightly extended surgical duration using additional stitches.

Conclusions

This study shows that RD AVR can be performed as safely and efficiently as RD AVR in patients with BAV with aortic stenosis, with or without concomitant cardiac surgery, even when compared with TAV outcomes. Although RD AVR in BAV can be technically demanding, BAV, including Sievers type 0, may not be a contraindication for RD AVR if the shape of the aortic annulus is carefully considered.

Acknowledgments

Funding: None.

Footnote

Reporting Checklist: The authors have completed the STROBE reporting checklist. Available at https://jtd.amegroups.com/article/view/10.21037/jtd-23-1942/rc

Data Sharing Statement: Available at https://jtd.amegroups.com/article/view/10.21037/jtd-23-1942/dss

Peer Review File: Available at https://jtd.amegroups.com/article/view/10.21037/jtd-23-1942/prf

Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://jtd.amegroups.com/article/view/10.21037/jtd-23-1942/coif). The authors have no conflicts of interest to declare.

Ethical Statement: The authors are accountable for all aspects of this work and ensure that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. This study was conducted in accordance with the principle of the Declaration of Helsinki (revised in 2013) and was approved by the Institutional Review Board (IRB) of Seoul St. Mary’s Hospital (IRB No. KC23RISI0665). The requirement for informed consent was waived due to the retrospective nature.

Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.

References

1. Santarpino G, Berretta P, Fischlein T, et al. Operative outcome of patients at low, intermediate, high and 'very high' surgical risk undergoing isolated aortic valve replacement with sutureless and rapid deployment prostheses: results of the SURD-IR registry. Eur J Cardiothorac Surg 2019;56:38-43. [Crossref] [PubMed]
2. Borger MA, Dohmen PM, Knosalla C, et al. Haemodynamic benefits of rapid deployment aortic valve replacement via a minimally invasive approach: 1-year results of a prospective multicentre randomized controlled trial. Eur J Cardiothorac Surg 2016;50:713-20. [Crossref] [PubMed]
3. Rahmanian PB, Kaya S, Eghbalzadeh K, et al. Rapid Deployment Aortic Valve Replacement: Excellent Results and Increased Effective Orifice Areas. Ann Thorac Surg 2018;105:24-30. [Crossref] [PubMed]
4. Sievers HH, Schmidtke C. A classification system for the bicuspid aortic valve from 304 surgical specimens. J Thorac Cardiovasc Surg 2007;133:1226-33. [Crossref] [PubMed]
5. Coti I, Werner P, Kaider A, et al. Rapid-deployment aortic valve replacement for patients with bicuspid aortic valve: a single-centre experience. Eur J Cardiothorac Surg 2022;62:ezac017. [Crossref] [PubMed]
6. Miceli A, Berretta P, Fiore A, et al. Sutureless and rapid deployment implantation in bicuspid aortic valve: results from the sutureless and rapid-deployment aortic valve replacement international registry. Ann Cardiothorac Surg 2020;9:298-304. [Crossref] [PubMed]
7. King M, Stambulic T, Payne D, et al. The use of sutureless and rapid-deployment aortic valve prosthesis in patients with bicuspid aortic valve: A focused review. J Card Surg 2022;37:3355-62. [Crossref] [PubMed]
8. Borger MA, Moustafine V, Conradi L, et al. A randomized multicenter trial of minimally invasive rapid deployment versus conventional full sternotomy aortic valve replacement. Ann Thorac Surg 2015;99:17-25. [Crossref] [PubMed]
9. Kocher AA, Laufer G, Haverich A, et al. One-year outcomes of the Surgical Treatment of Aortic Stenosis With a Next Generation Surgical Aortic Valve (TRITON) trial: a prospective multicenter study of rapid-deployment aortic valve replacement with the EDWARDS INTUITY Valve System. J Thorac Cardiovasc Surg 2013;145:110-5; discussion 115-6. [Crossref] [PubMed]
10. Romano MA, Koeckert M, Mumtaz MA, et al. Permanent Pacemaker Implantation After Rapid Deployment Aortic Valve Replacement. Ann Thorac Surg 2018;106:685-90. [Crossref] [PubMed]
11. Barnhart GR, Accola KD, Grossi EA, et al. TRANSFORM (Multicenter Experience With Rapid Deployment Edwards INTUITY Valve System for Aortic Valve Replacement) US clinical trial: Performance of a rapid deployment aortic valve. J Thorac Cardiovasc Surg 2017;153:241-251.e2. [Crossref] [PubMed]
12. Erfe JM, Malaisrie SC, Andrei AC, et al. Outcomes of Sutureless/Rapid Deployment Valves Compared to Traditional Bioprosthetic Aortic Valves. Ann Thorac Surg 2021;111:1884-91. [Crossref] [PubMed]
13. Berretta P, Meuris B, Kappert U, et al. Sutureless Versus Rapid Deployment Aortic Valve Replacement: Results From a Multicenter Registry. Ann Thorac Surg 2022;114:758-65. [Crossref] [PubMed]
14. Laufer G. The 10 Commandments of Rapid Deployment Intuity Valve Implantation. Innovations (Phila) 2023;18:316-9. [Crossref] [PubMed]
15. Nashef SA, Roques F, Sharples LD, et al. EuroSCORE II. Eur J Cardiothorac Surg 2012;41:734-44; discussion 744-5. [Crossref] [PubMed]
16. Puskas JD, Kilgo PD, Thourani VH, et al. The society of thoracic surgeons 30-day predicted risk of mortality score also predicts long-term survival. Ann Thorac Surg 2012;93:26-33; discussion 33-5. [Crossref] [PubMed]
17. Zoghbi WA, Jone PN, Chamsi-Pasha MA, et al. Guidelines for the Evaluation of Prosthetic Valve Function With Cardiovascular Imaging: A Report From the American Society of Echocardiography Developed in Collaboration With the Society for Cardiovascular Magnetic Resonance and the Society of Cardiovascular Computed Tomography. J Am Soc Echocardiogr 2024;37:2-63. [Crossref] [PubMed]
18. Andreas M, Wallner S, Habertheuer A, et al. Conventional versus rapid-deployment aortic valve replacement: a single-centre comparison between the Edwards Magna valve and its rapid-deployment successor. Interact Cardiovasc Thorac Surg 2016;22:799-805. [Crossref] [PubMed]
19. Theron A, Gariboldi V, Grisoli D, et al. Rapid Deployment of Aortic Bioprosthesis in Elderly Patients With Small Aortic Annulus. Ann Thorac Surg 2016;101:1434-41. [Crossref] [PubMed]
20. Dawkins S, Hobson AR, Kalra PR, et al. Permanent pacemaker implantation after isolated aortic valve replacement: incidence, indications, and predictors. Ann Thorac Surg 2008;85:108-12. [Crossref] [PubMed]
21. Mack MJ, Leon MB, Thourani VH, et al. Transcatheter Aortic-Valve Replacement with a Balloon-Expandable Valve in Low-Risk Patients. N Engl J Med 2019;380:1695-705. [Crossref] [PubMed]
22. Popma JJ, Deeb GM, Yakubov SJ, et al. Transcatheter Aortic-Valve Replacement with a Self-Expanding Valve in Low-Risk Patients. N Engl J Med 2019;380:1706-15. [Crossref] [PubMed]
23. Williams MR, Jilaihawi H, Makkar R, et al. The PARTNER 3 Bicuspid Registry for Transcatheter Aortic Valve Replacement in Low-Surgical-Risk Patients. JACC Cardiovasc Interv 2022;15:523-32. [Crossref] [PubMed]
24. Forrest JK, Ramlawi B, Deeb GM, et al. Transcatheter Aortic Valve Replacement in Low-risk Patients With Bicuspid Aortic Valve Stenosis. JAMA Cardiol 2021;6:50-7. [Crossref] [PubMed]
25. Steinberg BA, Harrison JK, Frazier-Mills C, et al. Cardiac conduction system disease after transcatheter aortic valve replacement. Am Heart J 2012;164:664-71. [Crossref] [PubMed]
26. Bouhout I, Mazine A, Rivard L, et al. Conduction Disorders After Sutureless Aortic Valve Replacement. Ann Thorac Surg 2017;103:1254-60. [Crossref] [PubMed]
27. Vola M, Guichard JB, Fuzellier JF, et al. Sutureless Valve Implantation in Sievers Type 0 Bicuspid Annuli: A Word of Caution. J Card Surg 2015;30:694-6. [Crossref] [PubMed]
28. Sakata T, De La Pena C, Ohira S. Rapid-Deployment Aortic Valve Replacement: Patient Selection and Special Considerations. Vasc Health Risk Manag 2023;19:169-80. [Crossref] [PubMed]
29. Tsai FC, Li HY, Chou AH, et al. Modified Implant Technique of Perceval Sutureless Valve in Congenital Type 0 Bicuspid Valve Stenosis. Ann Thorac Surg 2021;111:e369-71. [Crossref] [PubMed]
30. Di Eusanio M, Berretta P. The sutureless and rapid-deployment aortic valve replacement international registry: lessons learned from more than 4,500 patients. Ann Cardiothorac Surg 2020;9:289-97. [Crossref] [PubMed]
31. Berretta P, Arzt S, Fiore A, et al. Current trends of sutureless and rapid deployment valves: an 11-year experience from the Sutureless and Rapid Deployment International Registry. Eur J Cardiothorac Surg 2020;58:1054-62. [Crossref] [PubMed]
32. Hoffman JI, Kaplan S. The incidence of congenital heart disease. J Am Coll Cardiol 2002;39:1890-900. [Crossref] [PubMed]