Transcatheter aortic valve implantation in patients with small aortic annuli using a 20 mm balloon-expanding valve

The Evolving Role of Surgical Aortic Valve Replacement in the Era of Transcatheter Valvular Procedures

Surgical aortic valve replacement (SAVR) has long been the standard treatment for severe symptomatic aortic stenosis (AS). However, transcatheter aortic valve replacement (TAVR) has emerged as a minimally invasive alternative; it was initially intended for high-risk patients and has now expanded its use to patients of all risk groups. While TAVR has demonstrated promising outcomes in diverse patient populations, uncertainties persist regarding its long-term durability and potential complications, raising the issue of the ideal lifetime management strategy for patients with AS. Therefore, SAVR continues to play an important role in clinical practice, particularly in younger patients with longer life expectancies, those with complex aortic anatomy who are unsuitable for TAVR, and those requiring concomitant surgical procedures. The choice between TAVR and SAVR warrants personalized decision-making, considering patient characteristics, comorbidities, anatomical considerations, and overall life expectancy. A multidisciplinary approach involving an experienced heart team is crucial in the preoperative evaluation process. In this review, we aimed to explore the current role of surgical management in addressing aortic valve stenosis amidst the expanding utilization of less invasive transcatheter procedures.

Managing the challenge of a small aortic annulus in patients with severe aortic stenosis

INTRODUCTION

Small aortic annulus (SAA) poses a challenge in the management of patients with severe aortic stenosis requiring aortic valve replacement - both surgical and transcatheter - since it has been associated with worse clinical outcomes.

AREAS COVERED

This review aims to comprehensively summarize the available evidence regarding the management of aortic stenosis in patients with SAA and discuss the current controversies as well as future perspectives in this field.

EXPERT OPINION

It is paramount to agree in a common definition for diagnosing and properly treating SAA patients, and for that purpose, multidetector computer tomography is essential. The results of recent trials led to the expansion of transcatheter aortic valve replacement among patients of all the surgical-risk spectrum, and the choice of treatment (transcatheter, surgical) should be based on patient comorbidities, anatomical characteristics, and patient preferences.

Prosthetic Valve Function after Aortic Valve Replacement for Severe Aortic Stenosis by Transcatheter Procedure versus Surgery

Background This study compared the clinical outcomes of transcatheter (TAVR) and surgical (SAVR) aortic valve replacements, focusing on postoperative valvular performance assessed by echocardiography. Method and Results A total of 425 patients who underwent TAVR (230 patients) or SAVR (195 patients) were included. Postoperative effective orifice area index (EOAI) was higher in the TAVR group (1.27 ± 0.35 cm2/m2) than in the SAVR group (1.06 ± 0.27 cm2/m2, p < 0.001), and patient−prosthesis mismatch (PPM) was more frequent in the SAVR group (22.6%) than in the TAVR group (8.7%, p < 0.001). Mild or greater paravalvular leakage (PVL) was more frequent in the TAVR group (21.3%) than in the SAVR group (0%, p < 0.001). Moreover, there was no difference in freedom from all-cause death, stroke, or rehospitalization between the groups. Patients with moderate or greater PPM (EOAI < 0.85 cm2/m2) had lower freedom from composite events than those without this PPM criterion (p = 0.008). Patients with mild or greater PVL also had lower freedom from composite events than those without this PVL criterion (p = 0.017). Conclusions Postoperative valvular performance of TAVR was superior to that of SAVR in terms of EOAI. This merit was counterbalanced by the significantly lower rates of PVL in patients who underwent SAVR. The overall clinical outcomes were similar between the study groups.

Transcatheter Aortic Valve Replacement in Patients With a Small Annulus - From the Japanese Nationwide Registry (J-TVT)

BACKGROUND

The details and consequences of a small aortic annulus among transcatheter aortic valve replacement (TAVR) patients remain uncertain. This study investigated the short-term outcomes in patients with small annular size and compared the 30-day outcome between intra- and supra-annular devices, with similar outer casing diameter in this subgroup.Methods and Results:Cases registered in the Japanese national TAVR registry between August 2013 and December 2017 were analyzed. Among a total of 5,870 registered patients, 647 (11.0%) had small annulus (area ≤314 mm²) measured by multi-detector computed tomography. Patients with a small annulus had a significantly smaller indexed effective orifice area (iEOA, 1.10 cm²/m²[0.92-1.35] vs. 1.16 cm²/m²[0.96-1.39], P<0.001) and higher mean pressure gradient (mPG, 10.0 mmHg [6.9-14.2] vs. 8.5 mmHg [6.0-11.5], P<0.001) compared with a normal-sized annulus. Among patients with a small annulus, those receiving a 20 mm intra-annular device had a smaller iEOA (0.94 cm²/m²[0.78-1.06] vs. 1.07 cm²/m²[0.8-1.24], P=0.001) and higher mPG (14.0 mmHg [10.0-18.5] vs. 11.0 [7.0-14.0], P<0.001) compared with those receiving a 23-mm supra-annular device, although the incidence of paravalvular leakage (≥moderate) was similar (14.4% vs. 16.5%, P=0.69).

CONCLUSIONS

Patients with a small annulus were associated with less hemodynamic improvement. A supra-annular device is associated with better echocardiographic improvement in patients with a small annulus, without increasing paravalvular leakage.

Expansion of TAVR into Low-Risk Patients and Who to Consider for SAVR

Transcatheter aortic valve replacement (TAVR) has revolutionized the treatment of severe aortic stenosis (AS) over the last decade. The results of the Placement of Aortic Transcatheter Valves (PARTNER) 3 and Evolut Low Risk trials demonstrated the safety and efficacy of TAVR in low-surgical-risk patients and led to the approval of TAVR for use across the risk spectrum. Heart teams around the world will now be faced with evaluating a deluge of younger, healthier patients with severe AS. Prior to the PARTNER 3 and Evolut Low Risk studies, this heterogenous patient population would have undergone surgical aortic valve replacement (SAVR). It is unlikely that TAVR will completely supplant SAVR for the treatment of severe AS in patients with a low surgical risk, as SAVR has excellent short- and long-term outcomes and years of durability data. In this review, we outline the critical role that SAVR will continue to play in the treatment of severe AS in the post-PARTNER 3/Evolut Low Risk era.

New-Generation Transcatheter Aortic Valves in Patients With Small Aortic Annuli - Comparison of Balloon- and Self-Expandable Valves in Asian Patients

BACKGROUND

Asian patients have smaller aortic annuli. Although 20-mm balloon-expandable (BE) transcatheter heart valves (THV) are manufactured for transcatheter aortic valve implantation (TAVI) in these cases, the supra-annular design of self-expandable (SE) THV is considered more suitable; however, real-world comparative data are scarce.Methods and Results:Consecutive TAVI cases (n=330) in a single Japanese center were reviewed. Based on the cutoff for the new-generation 20-/23-mm BE-THV, a small aortic annulus was defined as <330 mm². A considerable number of patients had small annuli: 49/302 (16%). Of these, 33 BE-THV and 13 SE-THV using new-generation valves were compared. Although the SE-THV group had smaller annulus area (median 297 (interquartile range, 280-313) vs. 309 (303-323) mm²(P=0.022)), it had more favorable post-procedural parameters; for SE-THV and BE-THV, respectively, effective orifice area (EOA), 1.5 (1.3-1.6) vs. 1.1 cm²(0.9-1.3) (P=0.002); mean pressure gradient, 7.6 (5.6-11.0) vs. 14.2 mmHg (11.2-18.8) (P=0.001); and peak velocity, 1.8 (1.6-2.4) vs. 2.7 m/s (2.3-3.1) (P=0.001). Although new left bundle branch block was higher with SE-THV (24% and 62%, P=0.02), patient-prosthesis mismatch (PPM) ≥ moderate (indexed EOA <0.85 cm²/m²) was significantly less with SE-THV than with BE-THV (8% vs. 55%; P=0.04). Hemodynamic findings were consistent up to 1 year.

CONCLUSIONS

Small annuli are often seen in Asian patients, for whom SE-THV implantation results in favorable hemodynamics with less PPM.